US20180068853A1 - Diamond Semiconductor System and Method - Google Patents
Diamond Semiconductor System and Method Download PDFInfo
- Publication number
- US20180068853A1 US20180068853A1 US15/706,751 US201715706751A US2018068853A1 US 20180068853 A1 US20180068853 A1 US 20180068853A1 US 201715706751 A US201715706751 A US 201715706751A US 2018068853 A1 US2018068853 A1 US 2018068853A1
- Authority
- US
- United States
- Prior art keywords
- diamond
- dopant atoms
- lattice
- substitutional
- atoms
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 239000010432 diamond Substances 0.000 title claims abstract description 184
- 229910003460 diamond Inorganic materials 0.000 title claims abstract description 183
- 238000000034 method Methods 0.000 title claims abstract description 108
- 239000004065 semiconductor Substances 0.000 title claims abstract description 47
- 239000002019 doping agent Substances 0.000 claims abstract description 48
- 239000000463 material Substances 0.000 claims abstract description 46
- 238000000137 annealing Methods 0.000 claims abstract description 15
- 238000004519 manufacturing process Methods 0.000 claims abstract description 8
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 16
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims description 7
- 229910052796 boron Inorganic materials 0.000 claims description 7
- 239000000377 silicon dioxide Substances 0.000 claims description 7
- 230000037361 pathway Effects 0.000 claims description 5
- 235000012239 silicon dioxide Nutrition 0.000 claims description 4
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims description 3
- 229910052698 phosphorus Inorganic materials 0.000 claims description 2
- 239000011574 phosphorus Substances 0.000 claims description 2
- 239000002772 conduction electron Substances 0.000 abstract description 3
- 239000010410 layer Substances 0.000 description 45
- 125000004429 atom Chemical group 0.000 description 37
- 230000008021 deposition Effects 0.000 description 24
- 235000012431 wafers Nutrition 0.000 description 23
- 150000002500 ions Chemical class 0.000 description 22
- 239000010409 thin film Substances 0.000 description 17
- 229910052782 aluminium Inorganic materials 0.000 description 15
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 14
- 238000005530 etching Methods 0.000 description 14
- 229910052751 metal Inorganic materials 0.000 description 12
- 239000002184 metal Substances 0.000 description 12
- 239000007943 implant Substances 0.000 description 10
- 238000004140 cleaning Methods 0.000 description 9
- 238000010586 diagram Methods 0.000 description 8
- 238000005468 ion implantation Methods 0.000 description 8
- 239000002800 charge carrier Substances 0.000 description 6
- 238000009792 diffusion process Methods 0.000 description 6
- 238000004151 rapid thermal annealing Methods 0.000 description 5
- 229910052710 silicon Inorganic materials 0.000 description 5
- 239000010703 silicon Substances 0.000 description 5
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 238000002513 implantation Methods 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 239000000243 solution Substances 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- 238000013459 approach Methods 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 125000004432 carbon atom Chemical group C* 0.000 description 3
- 230000005684 electric field Effects 0.000 description 3
- 238000000206 photolithography Methods 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000000356 contaminant Substances 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 229910052737 gold Inorganic materials 0.000 description 2
- BHEPBYXIRTUNPN-UHFFFAOYSA-N hydridophosphorus(.) (triplet) Chemical compound [PH] BHEPBYXIRTUNPN-UHFFFAOYSA-N 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 230000000873 masking effect Effects 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 125000004437 phosphorous atom Chemical group 0.000 description 2
- 238000001020 plasma etching Methods 0.000 description 2
- 238000005498 polishing Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 229910052719 titanium Inorganic materials 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 1
- ASIIQTABPIPDFG-UHFFFAOYSA-L [Sn+2]=O.[F-].[F-] Chemical compound [Sn+2]=O.[F-].[F-] ASIIQTABPIPDFG-UHFFFAOYSA-L 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 230000005465 channeling Effects 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000010408 film Substances 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 239000005350 fused silica glass Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000005087 graphitization Methods 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- AMGQUBHHOARCQH-UHFFFAOYSA-N indium;oxotin Chemical compound [In].[Sn]=O AMGQUBHHOARCQH-UHFFFAOYSA-N 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 238000005215 recombination Methods 0.000 description 1
- 230000006798 recombination Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000005389 semiconductor device fabrication Methods 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 239000004590 silicone sealant Substances 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- 230000003746 surface roughness Effects 0.000 description 1
- 239000004094 surface-active agent Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/0405—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising semiconducting carbon, e.g. diamond, diamond-like carbon
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/0405—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising semiconducting carbon, e.g. diamond, diamond-like carbon
- H01L21/041—Making n- or p-doped regions
- H01L21/0415—Making n- or p-doped regions using ion implantation
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/22—Diffusion of impurity materials, e.g. doping materials, electrode materials, into or out of a semiconductor body, or between semiconductor regions; Interactions between two or more impurities; Redistribution of impurities
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
- H01L29/12—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
- H01L29/16—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed including, apart from doping materials or other impurities, only elements of Group IV of the Periodic Table
- H01L29/1602—Diamond
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
- H01L29/66007—Multistep manufacturing processes
- H01L29/66015—Multistep manufacturing processes of devices having a semiconductor body comprising semiconducting carbon, e.g. diamond, diamond-like carbon, graphene
- H01L29/66022—Multistep manufacturing processes of devices having a semiconductor body comprising semiconducting carbon, e.g. diamond, diamond-like carbon, graphene the devices being controllable only by variation of the electric current supplied or the electric potential applied, to one or more of the electrodes carrying the current to be rectified, amplified, oscillated or switched, e.g. two-terminal devices
- H01L29/6603—Diodes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
- H01L29/86—Types of semiconductor device ; Multistep manufacturing processes therefor controllable only by variation of the electric current supplied, or only the electric potential applied, to one or more of the electrodes carrying the current to be rectified, amplified, oscillated or switched
- H01L29/861—Diodes
- H01L29/868—PIN diodes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
- H01L2924/0001—Technical content checked by a classifier
- H01L2924/0002—Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
Definitions
- This invention is generally related to semiconductor systems and fabrication methods, and more particularly to a system and method for fabricating diamond semiconductors.
- Diamond possesses favorable theoretical semiconductor performance characteristics.
- practical diamond based semiconductor device applications remain limited.
- One issue that has limited the development of practical diamond based semiconductors is the difficulty of fabricating quality n-type layers in diamonds. While attempts have been made to improve n-type diamond fabrication based on limiting the concentration of vacancy created defects, the difficulties associated with fabricating quality n-type layers in diamond has yet to be sufficiently resolved. Therefore, there is a need for a new and improved system and method for fabricating diamond semiconductors, including n-type layers within diamond semiconductors.
- the system may include a diamond material having n-type donor atoms and a diamond lattice, wherein 0.16% of the donor atoms contribute conduction electrons with mobility greater than 770 cm 2 /Vs to the diamond lattice at 100 kPa and 300K.
- a method of fabricating diamond semiconductors may include the steps of selecting a diamond material having a diamond lattice; introducing a minimal amount of acceptor dopant atoms to the diamond lattice to create ion tracks; introducing substitutional dopant atoms to the diamond lattice through the ion tracks; and annealing the diamond lattice, wherein the introduction of the minimal amount of acceptor dopant atoms does not create a critical density of vacancies, and the introduction of the minimal amount of acceptor dopant atoms diminishes the resistive pressure capability of the diamond lattice.
- FIG. 1 is a block diagram of a first embodiment of the method for fabricating diamond semiconductors.
- FIG. 2A is a perspective view of a prior art model of an intrinsic diamond thin film wafer upon which the method of FIG. 1 may be practiced.
- FIG. 2B is a prior art model of an intrinsic diamond lattice structure of the diamond of FIG. 2A .
- FIG. 3A is a perspective view of an exemplary model of a doped diamond thin film wafer such as may be fabricated by practicing the method of FIG. 1 upon the intrinsic diamond thin film wafer of FIG. 2 .
- FIG. 3B is a model of a doped diamond lattice structure of the doped diamond thin film wafer of FIG. 3A .
- FIG. 4 is a block diagram of a second embodiment of the method for fabricating diamond semiconductors.
- FIG. 5A and FIG. 5B are block diagram of a third embodiment of the method for fabricating diamond semiconductors.
- FIG. 6 a top view of an exemplary P + -i-N diode model that may be fabricated according to the method of FIG. 5A and FIG. 5B .
- FIG. 7 is a perspective view of a model of an exemplary six-pin surface mount device package that may be fabricated according to the method of FIG. 5A and FIG. 5B .
- FIG. 8 shows a schematic diagram of a diode test condition setup, such as may be employed with the diode model of FIG. 6 .
- FIG. 9 is a graphical illustration of the threshold voltage performance characteristics of a diode that may be fabricated according to the method of FIG. 5A and FIG. 5B .
- FIG. 10 is a graphical illustration of the current-voltage characteristics of a diode that may be fabricated according to the method of FIG. 5A and FIG. 5B in forward bias.
- FIG. 11 is a graphical illustration of the current density characteristics of a diode that may be fabricated according to the method of FIG. 5A and FIG. 5B in forward bias.
- FIG. 12 is a graphical illustration of the current-voltage characteristics of a diode, that may be fabricated according to the method of FIG. 5A and FIG. 5B in reverse bias.
- FIG. 13 is a graphical illustration of the current density characteristics of a diode that may be fabricated according to the method of FIG. 5A and FIG. 5B in reverse bias.
- FIG. 14 shows a schematic illustration of an RF attenuator driver for use with a diode that may be fabricated according to the method of FIG. 5A and FIG. 5B .
- FIG. 1 shows a block diagram of a first embodiment of the method 100 for fabricating layers within diamond material.
- the method 100 may include a first step 102 of selecting a diamond material having a diamond lattice structure.
- the diamond material is intrinsic diamond.
- Intrinsic diamond is diamond that has not been intentionally doped. Doping may introduce impurities for the purpose of giving the diamond material electrical characteristics, such as, but not limited to, n-type characteristics and p-type characteristics.
- the diamond material may be a single crystal or polycrystalline diamond.
- FIG. 2A is a perspective view of a model of an intrinsic diamond thin film wafer 200 .
- the diamond material of method 100 is the intrinsic diamond thin film wafer 200 .
- the intrinsic diamond thin film wafer 200 may include a diamond layer 202 , a silicon dioxide layer (SiO 2 ) 204 , and a silicon wafer layer 206 .
- Diamond layer 202 may be, but is not limited to, ultrananocrystalline diamond.
- the intrinsic diamond thin film wafer 200 may be 100 mm in diameter.
- the diamond layer 202 may be a 1 ⁇ m polycrystalline diamond having a grain size of approximately 200-300 nm.
- the silicon dioxide layer (SiO 2 ) 204 may be approximately 1 ⁇ m.
- the silicon wafer layer 206 may be approximately 500 ⁇ m Si, such as Aqua 100 available from Advanced Diamond Technologies, Inc.
- the first step 102 of method 100 may include selecting a variety of diamond base materials such as, but not limited to, the exemplary diamond layer 202 of intrinsic diamond thin film wafer 200 .
- FIG. 2B is a model of an intrinsic diamond lattice structure 210 , such as, hut not limited to, an intrinsic diamond lattice structure of diamond layer 202 .
- the intrinsic diamond lattice structure 210 may include a plurality of carbon atoms 212 .
- the intrinsic diamond lattice structure 210 is known to those having skill in the art. In the model, the intrinsic diamond lattice structure 210 is shown defect free and all of the atoms shown are carbon atoms 212 .
- the second step 104 of method 100 may include introducing a minimal amount of acceptor dopant atoms to the diamond lattice to create ion tracks (shown in FIG. 3 as bounded by the lines 320 ).
- the creation of the ion tracks may include creation of a non-critical concentration of vacancies, for example, less than 10 22 /cm 3 for single crystal bulk volume, and a diminution of the resistive pressure capability of the diamond layer 202 .
- second step 104 may include introducing the acceptor dopant atoms using ion implantation at approximately 293 to 298 degrees Kelvin (K) in a low concentration.
- the acceptor dopant atoms may be p-type acceptor dopant atoms.
- the p-type dopant may be, but is not limited to, boron, hydrogen and lithium.
- the minimal amount of acceptor dopant atoms may be such that carbon dangling bonds will interact with the acceptor dopant atoms, but an acceptor level is not formed in the diamond lattice.
- the minimal amount of acceptor dopant atoms of second step 104 may be for example, but is not limited to, approximately 1 ⁇ 10 10 /cm 2 of boron. In other embodiments, the minimal amount of acceptor dopant atoms of second step 104 may be for example, but is not limited to, approximately 5 ⁇ 10 10 /cm 2 of boron and a range of 1 ⁇ 10 8 /cm 2 to 5 ⁇ 10 10 /cm 2 .
- Second step 104 may be accomplished by boron co-doping at room temperature in that created vacancies may be mobile, but boron may take interstitial positioning. The second step 104 may create mobile vacancies for subsequent dopants, in addition to some substitutional positioning.
- second step 104 may be viewed as a ballistic pathway for introduction of larger substitutional dopant atoms (see third step 106 below). Second step 104 may also eliminate the repulsive force (with respect to the substitutional dopant atoms (see step 106 below)) of the carbon dangling bonds in the diamond lattice by energetically favoring interstitial positioning of the acceptor dopant atoms, and altering the local formation energy dynamics of the diamond lattice.
- the third step 106 of method 100 may include introducing the substitutional dopant atoms to the diamond lattice through the ion tracks.
- third step 106 may include introducing the larger substitutional dopant atoms using ion implantation preferably at or below approximately 78 degrees K for energy implantation at less than 500 keV. Implanting below 78 degrees K may allow for the freezing of vacancies and interstitials in the diamond lattice, while maximizing substitutional implantation for the substitutional dopant atoms.
- the larger substitutional dopant atoms may be for example, but is not limited to, phosphorous, nitrogen, sulfur and oxygen.
- the desired ion energy is higher, as local self-annealing may occur, it may be beneficial to use ambient temperature in conjunction with MeV energy implantation. Where the desired ion energy is higher, there may be a higher probability of an incoming ion taking substitutional positioning.
- the larger substitutional dopant atoms may be introduced at a much higher concentration than the acceptor dopant atoms.
- the higher concentration of the larger substitutional dopant atoms may be, but is not limited to, approximately 9.9 ⁇ 10 17 /cm 3 of phosphorous and a range of 8 ⁇ 10 17 to 2 ⁇ 10 18 /cm 3 .
- the existence of the ballistic pathway and minimization of negative repulsive forces acting on the substitutional dopant atoms facilitates the entry of the substitutional dopant atoms into the diamond lattice with minimal additional lattice distortion.
- Ion implantation of the substitutional dopant atoms at or below approximately 78 degrees K provides better impurity positioning, favoring substitutional positioning over interstitial positioning, and also serves to minimize the diamond lattice distortions because fewer vacancies are created per impinging ion.
- ion implantation of step 106 may be performed at 140 keV, at a 6 degree offset to minimize channeling.
- Implant beam energy may be such that dosages overlap in an active implant area approximately 25 nm below the surface so that graphitic lattice relaxation is energetically unfavorable.
- Doping may be performed on a Varian Ion Implantation System with a phosphorus mass 31 singly ionized dopant (i.e., 31P+); a beam current of 0.8 ⁇ A; a beam energy of 140 keV; a beam dose 9.4 ⁇ 10 11 /cm 2 ; an incident angle of 6 degrees; and at a temperature of at or below approximately 78 degrees K.
- the fourth step 108 of method 100 may include subjecting the diamond lattice to rapid thermal annealing.
- the rapid thermal annealing may be done at 1000 degree celsius C. Rapid thermal annealing may restore portions of the diamond lattice that may have been damaged during the second step 104 and the third step 106 and may electrically activate the remaining dopant atoms that may not already be substitutional positioned. Higher temperatures at shorter time durations may be more beneficial than low temperature, longer duration anneals, as the damage recovery mechanism may shift during long anneal times at temperatures in excess of 600 C.
- FIG. 3A is a perspective view of a model of a doped diamond thin film wafer 300 , such as may be fabricated by subjecting the intrinsic diamond thin film wafer 200 to method 100 .
- the doped diamond thin film wafer 300 may include a doped diamond layer 302 , the silicon dioxide layer (SiO 2 ) 204 , and the silicon wafer layer 206 .
- FIG. 3B is a model of a doped diamond lattice structure 304 , such as may be the result of subjecting the diamond layer 202 to method 100 .
- the doped diamond lattice structure 304 may include a plurality of carbon atoms 314 , a plurality of phosphorus atoms 306 , and a plurality of vacancies 308 , and a boron atom 312 .
- the method 100 allows for the fabrication of a semiconductor system including a diamond material, such as, but not limited to, the doped diamond thin film wafer 300 , having n-type donor atoms, such as, but not limited to, the plurality of phosphorus atoms 306 , and a diamond lattice, such as, but not limited to, the doped diamond lattice structure 304 , wherein, for example by way of shallow ionization energy, approximately 0.25 eV, 0.16% of the donor atoms contribute conduction electrons with mobility greater than 770 cm2/Vs to the diamond lattice at 100 kPa and 300K.
- a diamond material such as, but not limited to, the doped diamond thin film wafer 300
- n-type donor atoms such as, but not limited to, the plurality of phosphorus atoms 306
- a diamond lattice such as, but not limited to, the doped diamond lattice structure 304
- FIG. 4 shows a block diagram of a second embodiment of the method 400 for fabricating layers within diamond material.
- the first step of method 400 may be the same as the first step 102 of method 100 , which includes selecting a diamond material having a diamond lattice structure.
- the second step 402 of method 400 may include cleaning the diamond material to remove surface contaminants.
- second step 402 may include cleaning the intrinsic diamond thin film wafer 200 (see FIG. 2 ).
- the cleaning may be a strong clean, for example but not limited to, a standard diffusion clean, known to those having skill in the art.
- a diffusion clean includes: applying a 4:1 solution of H 2 SO 4 /H 2 O 2 for 10 minutes; applying a solution of H 2 O 2 for 2.5 minutes; applying a 5:1:1 solution of H 2 O/H 2 O 2 /HCL for 10 minutes; applying a solution of H 2 O 2 for 2.5 minutes; and heat spin drying for 5 minutes.
- the third step 404 of method 400 may include subjecting the diamond material to a pre-ion track mask deposition over a first portion of the diamond lattice.
- the pre-ion track mask may protect a first portion of the diamond material during ion implantation.
- the pre-ion track mask deposition may be an aluminum pre-implant mask deposition.
- the pre-ion track mask deposition may be performed using a Gryphon Metal Sputter System using aluminum of 99.99999% (6N) purity, with a deposition time of 21-24 seconds, at a power of 7.5 kW, a pressure: 2.5 ⁇ 10 ⁇ 3 Torr; and to a thickness of 30 nm.
- the fourth step of method 400 may be the same as the second step 104 of method 100 , which includes introducing a minimal amount of acceptor dopant atoms to the diamond lattice to create ion tracks.
- the fifth step of method 400 may be the same as the third step 106 of method 100 , which includes introducing substitutional dopant atoms to the diamond lattice through the ion tracks.
- the sixth step 406 of method 400 may include mask etching, cleaning, and annealing the diamond lattice.
- the mask etching may be an aluminum mask etch.
- the mask etching may be a wet etch using aluminum etchant, for example, a Cyantek AL-11 Aluminum etchant mixture or an etchant having a composition of 72% phosphoric acid; 3% acetic acid; 3% nitric acid; 12% water; and 10% surfactant, at a rate of 1 ⁇ m per minute.
- aluminum etchant for example, a Cyantek AL-11 Aluminum etchant mixture or an etchant having a composition of 72% phosphoric acid; 3% acetic acid; 3% nitric acid; 12% water; and 10% surfactant, at a rate of 1 ⁇ m per minute.
- the mask etching of the sixth step 406 may be a blanket etch using reactive ion etching (Ar (35 SCCM)/O 2 (10 SCCM), at V BIAS 576 V, 250 W Power, under pressure of 50 mTorr, for a total etch thickness of 25 nm.
- the Ar/O 2 etch may have a dual function of both etching and polishing/terminating the diamond material surface.
- the same process recipe is later implemented to form device architecture, and define different active and inactive areas of the diamond, as per required by end application use (i.e., MOSFET, diode, LED, etc.).
- Etch masking layer for example a 200 nm thick aluminum deposition, may be formed via standard E-beam evaporation. Etching may be performed on an Oxford System 100 Plasmalab Equipment (Oxford Deep Reactive Ion Etcher).
- the etching conditions may be: RIE Power: 200 W; ICP power: 2000 W; Pressure: 9 mTorr; O 2 flow: 50 sccm; Ar flow: 1 sccm.
- the etching rates may be 155 nm/min for the diamond layer and 34 nm/min for the aluminum masking layer.
- the cleaning of sixth step 406 may be similar to diffusion clean described in the second step 402 .
- the annealing of sixth step 406 may be a rapid thermal annealing to approximately 1000-1150 degrees Celsius under flowing N 2 for approximately 5 minutes and/or the rapid thermal annealing may be performed with an Agilent RTA model AG4108 operating under the settings shown in Table 1,
- the sixth step 406 of method 400 may include subjecting the diamond material to a pre-substitutional mask deposition over a portion of the diamond lattice.
- the pre-substitutional mask deposition may be an aluminum pre-implant mask deposition.
- the pre-substitutional mask deposition may be performed using a Gryphon Metal Sputter System using aluminum of 99.99999% (6N) purity, with a deposition time of 21-24 seconds, at a power of 7.5 kW, a pressure: 2.5 ⁇ 10 ⁇ 3 Torr; and to a thickness of 30 nm.
- various semiconductor devices are created including P-N junctions and P-i-N junctions.
- FIG. 5A and FIG. 5B show a block diagram of a third embodiment of the method 500 for fabricating layers within diamond material.
- Method 500 provides a process for fabricating n-type layers within diamond semiconductors for a P + -i-N diode.
- the first step of method 500 may be the same as the first step 102 of method 100 , which includes selecting a diamond material having a diamond lattice structure.
- FIG. 6 shows a top view of an exemplary model of a P + -i-N diode 600 that may be fabricated according to method 500 .
- P + -i-N diode 600 may include a lightly doped semiconductor region (i) (for example, see FIG. 8, 804 ), between a pt-type semiconductor region 608 , and an n-type semiconductor region 606 .
- the method of 500 with SRIM, Stopping and Range of ions in Matter, modeling provides a path for fabricating P + -i-N diodes that approach theoretical projections.
- the P + -i-N diode 600 may include the lightly doped semiconductor region (i) 804 of a depth of approximately 10 nm, between a p-type semiconductor (for example, see FIG. 8, 806 ) of a depth of approximately 150 nm, the p + -type semiconductor region 608 of a depth of approximately 100 nm, and the n-type semiconductor region 606 of a depth of approximately 100 nm. 6 also shows a metallic contact/bonding pad 604 for connecting to the p + -type semiconductor region 608 .
- the second step of method 500 may be the same as the second step 402 of method 400 , including cleaning the diamond material to remove surface contaminants.
- the third step 502 of method 500 may include subjecting the diamond material to a pre-P + mask deposition over a non-P + portion of the diamond lattice.
- the pre-P + mask deposition may protect a non-P + portion of the diamond material during P + ion implantation.
- the pre-P + mask deposition may be an aluminum pre-implant mask deposition.
- the pre-ion track mask deposition may be performed using a Gryphon Metal Sputter System using aluminum of 99.99999% (6N) purity, with a deposition time of 21-24 seconds, at a power of 7.5 kW, a pressure: 2.5 ⁇ 10 ⁇ 3 Torr; and to a thickness of 30 nm.
- the fourth step 504 of method 500 may include a P + layer implant of the diamond material.
- the P + layer implant may be performed with a dopant of 11B + , at a beam current of 0.04 ⁇ A, at a beam energy of 55 keV, with a beam dose of 1 ⁇ 10 20 atoms/cm 2 , at an incident angle of 6 degrees, and at or below approximately 78 degrees K, to create a P + layer of 100 nm.
- the fifth step of method 500 may be the same as the sixth step 406 of method 400 , including mask etching, cleaning, and annealing the diamond material.
- the sixth step 506 of method 500 may include subjecting the diamond material to a pre-P mask deposition over a non-P portion of the diamond lattice.
- the pre-P mask deposition may protect a non-P portion of the diamond material during P ion implantation.
- the pre-P mask deposition may be an aluminum pre-implant mask deposition.
- the pre-P mask deposition may be performed using a Gryphon Metal Sputter System using aluminum of 99.99999% (6N) purity, with a deposition time of 21-24 seconds, at a power of 7.5 kW, a pressure: 2.5 ⁇ 10 ⁇ 3 Torr; and to a thickness of 30 nm.
- the seventh step 508 of method 500 may include a P layer implant of the diamond material.
- the P layer implant may be performed with a dopant of 11B + , at a beam current of 0.04 ⁇ A, at a beam energy of 55 keV, with a beam dose of 3 ⁇ 10 17 atoms/cm 2 , at an incident angle of 6 degrees, and at or below approximately 78 degrees K, to create a P layer of 150 nm.
- the eighth step of method 500 may be the same as the sixth step 406 of method 400 , including mask etching, cleaning, and annealing the diamond material.
- the ninth step of method 500 may be the same as the third step 404 of method 400 , including subjecting the diamond material to a pre-ion track mask deposition over a first portion of the diamond lattice.
- the tenth step of method 500 may be the same as the second step 104 of method 100 , which includes introducing a minimal amount of acceptor dopant atoms to the diamond lattice to create ion tracks.
- the eleventh step of method 500 may be the same as the third step 106 of method 100 , which includes introducing substitutional dopant atoms to the diamond lattice through the ion tracks.
- the twelfth step of method 500 may be same as the sixth step 406 of method 400 , including mask etching, cleaning, and annealing the diamond material.
- the thirteenth step 510 of method 500 may include a blanket etch.
- the thirteenth step 510 may include a blanket etch in which the surface layer, approximately 25 nm, of the diamond layer 202 is etched off to remove any surface graphitization.
- the fourteenth step 512 of method 500 may include a photolithography/mesa etch to obtain a diamond stack structure, such as that shown in FIG. 6 .
- the fourteenth step 512 may include a diffusion clean and photolithography prior to the mesa etch.
- the fifteenth step 514 of method 500 may include a creating a contact for the top of the stack. Contact to the top of the stack may be achieved by evaporating ITO with 5N purity to a thickness of 200 nm onto the stack through a shadow mask and then performing a liftoff.
- the sixteenth step 516 of method 500 may include annealing.
- the annealing of step 516 may be oven annealing at 420 degrees C. in Ar ambient until ITO transparency is attained, which may be in approximately 2.5 hours.
- the seventeenth step 518 of method 500 may include creating ohmic contacts.
- the ohmic contacts may include contacts to the layer, for example, the metallic contact/bonding pad 604 , and the n-layer.
- Ti and Au layers may be evaporated through a shadow mask using photolithography. Ti may also function as a diffusion barrier between ITO and Au layers.
- a contact layer thickness of 30 nm may be created for the P layer.
- a contact layer thickness of 200 nm may be created for the N-layer.
- the diamond cap layer may be removed to expose the newly formed n-type layer to form an electrical contact for device use.
- the step may include polishing the diamond layer while etching, thus minimizing the surface roughness, and electrically terminating (oxygen) the surface of the diamond, a step in semiconductor device fabrication.
- the seventeenth step 518 of method 500 may include a metal furnace annealing. The metal furnace annealing may be performed at 420 degrees celsius for two hours.
- the eighteenth step 520 of method 500 may include wafer surface termination.
- the nineteenth step 522 of method 500 may include wafer surface dicing.
- the twentieth step 524 of method 500 may include packaging.
- portions of the diamond material may be diced, mounted, wire bound and encapsulated in transparent silicone sealant to create 6-pin surface mount device packages.
- FIG. 7 shows a perspective view of a model of an exemplary six-pin surface mount device package 700 that may be fabricated according to the method of FIG. 5A and FIG. 5B .
- the methods disclosed herein may allow for the creation of a number of electrical diamond junctions to serve functions traditionally served by silicon semiconductors. While the application discusses examples in the context of a bipolar diode, those having skill in the art will recognize that the present techniques describe novel genuine n-type diamond material and novel p-type diamond material that may be used in multiple variations of electrical devices and monolithically formed combinations of the variations, including FETs and other switches, digital and analog, and light emitting bodies, and are not limited to the specific implementations shown herein. The various preferred embodiments need not necessarily be separate from each other and can be combined.
- FIG. 8 shows a schematic diagram of a P + -i-N diode test condition setup 802 .
- a P + -i-N diode such as a P + -i-N diode 600 fabricated according to method 500 , may be tested according to the P + -i-N diode test condition setup 802 .
- FIG. 9 is a graphical illustration 900 of the threshold voltage performance characteristics 902 of a P + -i-N diode that may be fabricated according to method 500 .
- the threshold voltage performance characteristics 902 may be obtained based upon DC conditions using suitable resistor biasing, and RF′ conditions using suitable TTL drivers or hybrid wire configuration, at room temperature, 76 degrees F. by IR measurement, under both low field and high field conditions.
- the threshold voltage performance characteristics 902 indicates a threshold voltage and current levels similar to those theoretically predicted for diamond.
- FIG. 10 is a graphical illustration 1000 of the current-voltage characteristics of a P + -i-N diode, such as a P + -i-N diode 600 fabricated according to method 500 , in forward bias, with the cathode negative, at room temperatures.
- a current-voltage curve 1002 shows the current-voltage characteristics for such a P + -i-N diode that may be fabricated according to method 500 .
- the current-voltage curve 1002 indicates a large concentration of electrons are available for conduction at room temperatures.
- a low voltage depletion region 1004 of the current-voltage curve 1002 shows charge carriers are diffused from the N layer and the P layer into the intrinsic region, for example, charge carriers are diffused from the n-type semiconductor region 606 and the between a p + -type semiconductor region 608 , into the lightly doped semiconductor region (i) 804 .
- the charge carriers may combine. Since recombination does not occur instantly, charge may be stored in the lightly doped semiconductor region (i) 804 , thus lowering resistivity.
- a high injection region 1006 of the current-voltage curve 1002 shows that as an applied potential is increased, charge carriers may flood into the intrinsic region, for example the lightly doped semiconductor region (i) 804 , resulting in a concentration of carriers in excess of equilibrium concentrations.
- a series resistance region 1008 of the current-voltage curve 1002 is also shown.
- FIG. 11 is a graphical illustration 1100 of the current density characteristics of a P + -i-N diode, such as a P + -i-N diode 600 fabricated according to method 500 , in forward bias, with the cathode negative, at room temperatures.
- a current density curve 1102 shows the current density characteristics for such a P + -i-N diode that may be fabricated according to method 500 .
- the current density curve 1102 shows a concentration of charge carrier types at current densities of greater than 1600 Amperes/cm 2 at 5 V.
- FIG. 12 is a graphical illustration 1200 of the current-voltage characteristics of a P + -i-N diode, such as a P + -i-N diode 600 fabricated according to method 500 , in reverse bias, with the cathode positive, at room temperatures.
- a current-voltage curve 1202 shows the current-voltage characteristics for such a P + -i-N diode that may be fabricated according to method 500 .
- the current-voltage curve 1202 shows that a small amount of reverse voltage may be required before the depletion region width becomes fully depleted of charge carriers and carrier diffusion ceases, as indicated by the small rise and rapid decrease in current levels.
- FIG. 13 is a graphical illustration 1300 of the current density characteristics of a P + -i-N diode, such as a P + -i-N diode 600 fabricated according to method 500 , in reverse bias, with the cathode positive, at room temperatures.
- a current density curve 1302 shows the current density characteristics for such a P + -i-N diode that may be fabricated according to method 500 .
- the current density curve 1302 shows a a P + -i-N diode, such as a P + -i-N diode 600 , is suited for signal attenuation, such as but not limited, to RI signal attenuation, as modulation is controllable.
- FIG. 14 shows a schematic illustration of an RF attenuator driver chip configuration 1400 , for use with a P + -i-N diode, such as a P + -i-N diode 600 fabricated according to method 500 .
- RF attenuator 1400 may provide attenuation characteristics with R load varying from approximately 10 K ⁇ to 1 m ⁇ , current controlled characteristic, at 77 KHz.
- the systems and fabrication methods described herein provide a number of new and useful technologies, including novel n-type and novel p-type diamond semiconducting materials and devices, and methods for fabricating novel n-type and novel p-type diamond semiconducting materials and devices.
- novel fabrication methods include, but are not limited to, those for creating, etching, and metalizing (Schottky and Ohmic) genuine quality n-type diamond material; creating Integrated. Circuits (ICs) and device drivers from diamond based power elements.
- the novel devices include, but are not limited to, n-type diamond semiconductors that are at least partially activated at room temperature—i.e., the device material has sufficient carrier concentration to activate and participate in conduction; n-type diamond with high electron mobility; n-type diamond which has both high carrier mobility and high carrier concentration—without requiring a high temperature (above room temperature) or the presence of a high electrical field; an n-type diamond semiconductor with an estimated electron mobility in excess of 1,000 cm 2 /Vs and a carrier concentration of approximately 1 ⁇ 10 16 electrons/cm 3 at room/ambient temperature; a bipolar diamond semiconductor device; devices with p-type and n-type regions on a single diamond wafer; diamond diode devices; bipolar diamond semiconductor devices carrying high current without necessitating either a high temperature or the presence of a strong electrical field; bipolar diamond semiconductor devices which can carry a one milliamp current while at room temperature and in the presence of a 0.28V electrical field; an n-type diamond material on polycrystalline diamond; a
- this n-type and novel p-type diamond semiconducting material is constructed using polycrystalline diamond having less than a micrometer size grain and with doped thin film layers having sizes on the order of less than 900 nm.
- the techniques for forming said diamond material may be used on diamond films with diamond grain boundaries that are nearly atomic abrupt, such that uniformity of electrical performance may be maintained, while enabling the ability to form thin-film features from said material.
- metal contacts attached to the diamond semiconducting material, including the n-type material. Said metal contacts attach to the diamond material and continue to have good/ohmic conductivity (e.g., displaying high linearity).
- Metal contacts may refer to either or both metals (e.g., Au, Ag, Al, Ti, Pd, Pt, etc.) or transparent metals (e.g., indium tin oxide, fluoride tin oxide, etc.), as warranted by desired application use.
Landscapes
- Engineering & Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- General Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Manufacturing & Machinery (AREA)
- Ceramic Engineering (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
- Electrodes Of Semiconductors (AREA)
- Carbon And Carbon Compounds (AREA)
- Bipolar Transistors (AREA)
Abstract
Disclosed herein is a new and improved system and method for fabricating diamond semiconductors. The system may include a diamond material having n-type donor atoms and a diamond lattice, wherein 0.16% of the donor atoms contribute conduction electrons with mobility greater than 770 cm2/Vs to the diamond lattice at 100 kPa and 300K. The method of fabricating diamond semiconductors may include the steps of selecting a diamond material having a diamond lattice; introducing a minimal amount of acceptor dopant atoms to the diamond lattice to create ion tracks; introducing substitutional dopant atoms to the diamond lattice through the ion tracks; and annealing the diamond lattice.
Description
- This application claims the benefit of U.S. Provisional Application No. 61/513,569, filed Jul. 30, 2011; U.S. application Ser. No. 13/273,467, filed Oct. 14, 2011; and U.S. application Ser. No. 14/581,030, filed Dec. 23, 2014.
- This invention is generally related to semiconductor systems and fabrication methods, and more particularly to a system and method for fabricating diamond semiconductors.
- Diamond possesses favorable theoretical semiconductor performance characteristics. However, practical diamond based semiconductor device applications remain limited. One issue that has limited the development of practical diamond based semiconductors is the difficulty of fabricating quality n-type layers in diamonds. While attempts have been made to improve n-type diamond fabrication based on limiting the concentration of vacancy created defects, the difficulties associated with fabricating quality n-type layers in diamond has yet to be sufficiently resolved. Therefore, there is a need for a new and improved system and method for fabricating diamond semiconductors, including n-type layers within diamond semiconductors.
- Disclosed herein is a new and improved system and method for fabricating diamond semiconductors. In accordance with one aspect of the approach, the system may include a diamond material having n-type donor atoms and a diamond lattice, wherein 0.16% of the donor atoms contribute conduction electrons with mobility greater than 770 cm2/Vs to the diamond lattice at 100 kPa and 300K.
- In another aspect of the approach, a method of fabricating diamond semiconductors may include the steps of selecting a diamond material having a diamond lattice; introducing a minimal amount of acceptor dopant atoms to the diamond lattice to create ion tracks; introducing substitutional dopant atoms to the diamond lattice through the ion tracks; and annealing the diamond lattice, wherein the introduction of the minimal amount of acceptor dopant atoms does not create a critical density of vacancies, and the introduction of the minimal amount of acceptor dopant atoms diminishes the resistive pressure capability of the diamond lattice.
- Other systems, methods, aspects, features, embodiments and advantages of the system and method for fabricating diamond semiconductors disclosed herein will be, or will become, apparent to one having ordinary skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, aspects, features, embodiments and advantages be included within this description, and be within the scope of the accompanying claims.
- It is to be understood that, the drawings are solely for purpose of illustration. Furthermore, the components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the system disclosed herein. In the figures, like reference numerals designate corresponding parts throughout the different views.
-
FIG. 1 is a block diagram of a first embodiment of the method for fabricating diamond semiconductors. -
FIG. 2A is a perspective view of a prior art model of an intrinsic diamond thin film wafer upon which the method ofFIG. 1 may be practiced. -
FIG. 2B is a prior art model of an intrinsic diamond lattice structure of the diamond ofFIG. 2A . -
FIG. 3A is a perspective view of an exemplary model of a doped diamond thin film wafer such as may be fabricated by practicing the method ofFIG. 1 upon the intrinsic diamond thin film wafer ofFIG. 2 . -
FIG. 3B is a model of a doped diamond lattice structure of the doped diamond thin film wafer ofFIG. 3A . -
FIG. 4 is a block diagram of a second embodiment of the method for fabricating diamond semiconductors. -
FIG. 5A andFIG. 5B are block diagram of a third embodiment of the method for fabricating diamond semiconductors. -
FIG. 6 a top view of an exemplary P+-i-N diode model that may be fabricated according to the method ofFIG. 5A andFIG. 5B . -
FIG. 7 is a perspective view of a model of an exemplary six-pin surface mount device package that may be fabricated according to the method ofFIG. 5A andFIG. 5B . -
FIG. 8 shows a schematic diagram of a diode test condition setup, such as may be employed with the diode model ofFIG. 6 . -
FIG. 9 is a graphical illustration of the threshold voltage performance characteristics of a diode that may be fabricated according to the method ofFIG. 5A andFIG. 5B . -
FIG. 10 is a graphical illustration of the current-voltage characteristics of a diode that may be fabricated according to the method ofFIG. 5A andFIG. 5B in forward bias. -
FIG. 11 is a graphical illustration of the current density characteristics of a diode that may be fabricated according to the method ofFIG. 5A andFIG. 5B in forward bias. -
FIG. 12 is a graphical illustration of the current-voltage characteristics of a diode, that may be fabricated according to the method ofFIG. 5A andFIG. 5B in reverse bias. -
FIG. 13 is a graphical illustration of the current density characteristics of a diode that may be fabricated according to the method ofFIG. 5A andFIG. 5B in reverse bias. -
FIG. 14 shows a schematic illustration of an RF attenuator driver for use with a diode that may be fabricated according to the method ofFIG. 5A andFIG. 5B . - The following detailed description, which references to and incorporates the drawings, describes and illustrates one or more specific embodiments. These embodiments, offered not to limit but only to exemplify and teach, are shown and described in sufficient detail to enable those skilled in the art to practice what is claimed. Thus, for the sake of brevity, the description may omit certain information known to those of skill in the art.
-
FIG. 1 shows a block diagram of a first embodiment of themethod 100 for fabricating layers within diamond material. Themethod 100 may include afirst step 102 of selecting a diamond material having a diamond lattice structure. The diamond material is intrinsic diamond. Intrinsic diamond is diamond that has not been intentionally doped. Doping may introduce impurities for the purpose of giving the diamond material electrical characteristics, such as, but not limited to, n-type characteristics and p-type characteristics. The diamond material may be a single crystal or polycrystalline diamond. -
FIG. 2A is a perspective view of a model of an intrinsic diamondthin film wafer 200. Though not limited to any particular diamond material, in one embodiment, the diamond material ofmethod 100 is the intrinsic diamondthin film wafer 200. The intrinsic diamondthin film wafer 200 may include adiamond layer 202, a silicon dioxide layer (SiO2) 204, and asilicon wafer layer 206.Diamond layer 202 may be, but is not limited to, ultrananocrystalline diamond. The intrinsic diamondthin film wafer 200 may be 100 mm in diameter. Thediamond layer 202 may be a 1 μm polycrystalline diamond having a grain size of approximately 200-300 nm. The silicon dioxide layer (SiO2) 204 may be approximately 1 μm. Thesilicon wafer layer 206 may be approximately 500 μm Si, such asAqua 100 available from Advanced Diamond Technologies, Inc. Thefirst step 102 ofmethod 100 may include selecting a variety of diamond base materials such as, but not limited to, theexemplary diamond layer 202 of intrinsic diamondthin film wafer 200. -
FIG. 2B is a model of an intrinsicdiamond lattice structure 210, such as, hut not limited to, an intrinsic diamond lattice structure ofdiamond layer 202. The intrinsicdiamond lattice structure 210 may include a plurality ofcarbon atoms 212. The intrinsicdiamond lattice structure 210 is known to those having skill in the art. In the model, the intrinsicdiamond lattice structure 210 is shown defect free and all of the atoms shown arecarbon atoms 212. - The
second step 104 ofmethod 100 may include introducing a minimal amount of acceptor dopant atoms to the diamond lattice to create ion tracks (shown inFIG. 3 as bounded by the lines 320). The creation of the ion tracks may include creation of a non-critical concentration of vacancies, for example, less than 1022/cm3 for single crystal bulk volume, and a diminution of the resistive pressure capability of thediamond layer 202. For example,second step 104 may include introducing the acceptor dopant atoms using ion implantation at approximately 293 to 298 degrees Kelvin (K) in a low concentration. The acceptor dopant atoms may be p-type acceptor dopant atoms. The p-type dopant may be, but is not limited to, boron, hydrogen and lithium. The minimal amount of acceptor dopant atoms may be such that carbon dangling bonds will interact with the acceptor dopant atoms, but an acceptor level is not formed in the diamond lattice. - The minimal amount of acceptor dopant atoms of
second step 104 may be for example, but is not limited to, approximately 1×1010/cm2 of boron. In other embodiments, the minimal amount of acceptor dopant atoms ofsecond step 104 may be for example, but is not limited to, approximately 5×1010/cm2 of boron and a range of 1×108/cm2 to 5×1010/cm2.Second step 104 may be accomplished by boron co-doping at room temperature in that created vacancies may be mobile, but boron may take interstitial positioning. Thesecond step 104 may create mobile vacancies for subsequent dopants, in addition to some substitutional positioning. - The ion tracks of
second step 104 may be viewed as a ballistic pathway for introduction of larger substitutional dopant atoms (seethird step 106 below).Second step 104 may also eliminate the repulsive force (with respect to the substitutional dopant atoms (seestep 106 below)) of the carbon dangling bonds in the diamond lattice by energetically favoring interstitial positioning of the acceptor dopant atoms, and altering the local formation energy dynamics of the diamond lattice. - The
third step 106 ofmethod 100 may include introducing the substitutional dopant atoms to the diamond lattice through the ion tracks. For example,third step 106 may include introducing the larger substitutional dopant atoms using ion implantation preferably at or below approximately 78 degrees K for energy implantation at less than 500 keV. Implanting below 78 degrees K may allow for the freezing of vacancies and interstitials in the diamond lattice, while maximizing substitutional implantation for the substitutional dopant atoms. The larger substitutional dopant atoms may be for example, but is not limited to, phosphorous, nitrogen, sulfur and oxygen. - For implantation where the desired ion energy is higher, as local self-annealing may occur, it may be beneficial to use ambient temperature in conjunction with MeV energy implantation. Where the desired ion energy is higher, there may be a higher probability of an incoming ion taking substitutional positioning.
- The larger substitutional dopant atoms may be introduced at a much higher concentration than the acceptor dopant atoms. The higher concentration of the larger substitutional dopant atoms may be, but is not limited to, approximately 9.9×1017/cm3 of phosphorous and a range of 8×1017 to 2×1018/cm3.
- In
third step 106, the existence of the ballistic pathway and minimization of negative repulsive forces acting on the substitutional dopant atoms facilitates the entry of the substitutional dopant atoms into the diamond lattice with minimal additional lattice distortion. Ion implantation of the substitutional dopant atoms at or below approximately 78 degrees K provides better impurity positioning, favoring substitutional positioning over interstitial positioning, and also serves to minimize the diamond lattice distortions because fewer vacancies are created per impinging ion. - In one embodiment, ion implantation of
step 106 may be performed at 140 keV, at a 6 degree offset to minimize channeling. Implant beam energy may be such that dosages overlap in an active implant area approximately 25 nm below the surface so that graphitic lattice relaxation is energetically unfavorable. Doping may be performed on a Varian Ion Implantation System with a phosphorus mass 31 singly ionized dopant (i.e., 31P+); a beam current of 0.8 μA; a beam energy of 140 keV; a beam dose 9.4×1011/cm2; an incident angle of 6 degrees; and at a temperature of at or below approximately 78 degrees K. - The
fourth step 108 ofmethod 100 may include subjecting the diamond lattice to rapid thermal annealing. The rapid thermal annealing may be done at 1000 degree celsius C. Rapid thermal annealing may restore portions of the diamond lattice that may have been damaged during thesecond step 104 and thethird step 106 and may electrically activate the remaining dopant atoms that may not already be substitutional positioned. Higher temperatures at shorter time durations may be more beneficial than low temperature, longer duration anneals, as the damage recovery mechanism may shift during long anneal times at temperatures in excess of 600 C. -
FIG. 3A is a perspective view of a model of a doped diamondthin film wafer 300, such as may be fabricated by subjecting the intrinsic diamondthin film wafer 200 tomethod 100. The doped diamondthin film wafer 300 may include a dopeddiamond layer 302, the silicon dioxide layer (SiO2) 204, and thesilicon wafer layer 206. -
FIG. 3B is a model of a dopeddiamond lattice structure 304, such as may be the result of subjecting thediamond layer 202 tomethod 100. The dopeddiamond lattice structure 304 may include a plurality ofcarbon atoms 314, a plurality ofphosphorus atoms 306, and a plurality ofvacancies 308, and aboron atom 312. - The
method 100 allows for the fabrication of a semiconductor system including a diamond material, such as, but not limited to, the doped diamondthin film wafer 300, having n-type donor atoms, such as, but not limited to, the plurality ofphosphorus atoms 306, and a diamond lattice, such as, but not limited to, the dopeddiamond lattice structure 304, wherein, for example by way of shallow ionization energy, approximately 0.25 eV, 0.16% of the donor atoms contribute conduction electrons with mobility greater than 770 cm2/Vs to the diamond lattice at 100 kPa and 300K. -
FIG. 4 shows a block diagram of a second embodiment of themethod 400 for fabricating layers within diamond material. The first step ofmethod 400 may be the same as thefirst step 102 ofmethod 100, which includes selecting a diamond material having a diamond lattice structure. - The
second step 402 ofmethod 400 may include cleaning the diamond material to remove surface contaminants. For example,second step 402 may include cleaning the intrinsic diamond thin film wafer 200 (seeFIG. 2 ). The cleaning may be a strong clean, for example but not limited to, a standard diffusion clean, known to those having skill in the art. One example, of such a diffusion clean includes: applying a 4:1 solution of H2SO4/H2O2 for 10 minutes; applying a solution of H2O2 for 2.5 minutes; applying a 5:1:1 solution of H2O/H2O2/HCL for 10 minutes; applying a solution of H2O2 for 2.5 minutes; and heat spin drying for 5 minutes. - The
third step 404 ofmethod 400 may include subjecting the diamond material to a pre-ion track mask deposition over a first portion of the diamond lattice. The pre-ion track mask may protect a first portion of the diamond material during ion implantation. The pre-ion track mask deposition may be an aluminum pre-implant mask deposition. The pre-ion track mask deposition may be performed using a Gryphon Metal Sputter System using aluminum of 99.99999% (6N) purity, with a deposition time of 21-24 seconds, at a power of 7.5 kW, a pressure: 2.5×10−3 Torr; and to a thickness of 30 nm. - The fourth step of
method 400 may be the same as thesecond step 104 ofmethod 100, which includes introducing a minimal amount of acceptor dopant atoms to the diamond lattice to create ion tracks. - The fifth step of
method 400 may be the same as thethird step 106 ofmethod 100, which includes introducing substitutional dopant atoms to the diamond lattice through the ion tracks. - The
sixth step 406 ofmethod 400 may include mask etching, cleaning, and annealing the diamond lattice. The mask etching may be an aluminum mask etch. The mask etching may be a wet etch using aluminum etchant, for example, a Cyantek AL-11 Aluminum etchant mixture or an etchant having a composition of 72% phosphoric acid; 3% acetic acid; 3% nitric acid; 12% water; and 10% surfactant, at a rate of 1 μm per minute. After the aluminum is removed visually, which may take approximately 30 seconds, the wafers may be run under de-ionized water for sixty seconds and dried via pressurized air gun. - In other embodiments, the mask etching of the
sixth step 406 may be a blanket etch using reactive ion etching (Ar (35 SCCM)/O2 (10 SCCM), at VBIAS 576 V, 250 W Power, under pressure of 50 mTorr, for a total etch thickness of 25 nm. The Ar/O2 etch may have a dual function of both etching and polishing/terminating the diamond material surface. In addition to initial etching, the same process recipe is later implemented to form device architecture, and define different active and inactive areas of the diamond, as per required by end application use (i.e., MOSFET, diode, LED, etc.). Etch masking layer, for example a 200 nm thick aluminum deposition, may be formed via standard E-beam evaporation. Etching may be performed on anOxford System 100 Plasmalab Equipment (Oxford Deep Reactive Ion Etcher). The etching conditions may be: RIE Power: 200 W; ICP power: 2000 W; Pressure: 9 mTorr; O2 flow: 50 sccm; Ar flow: 1 sccm. The etching rates may be 155 nm/min for the diamond layer and 34 nm/min for the aluminum masking layer. - The cleaning of
sixth step 406 may be similar to diffusion clean described in thesecond step 402. The annealing ofsixth step 406 may be a rapid thermal annealing to approximately 1000-1150 degrees Celsius under flowing N2 for approximately 5 minutes and/or the rapid thermal annealing may be performed with an Agilent RTA model AG4108 operating under the settings shown in Table 1, -
TABLE 1 Command Time(s)/Intensity (%) Temperature Gas Flow Delay 20 s N/A 10 SLPM N2 Delay 5 s N/A 7 SLPM N2 Inin 8% 25° C. 4 SLPM N2 Ramp 10 s 650° C. 4 SLPM N2 Steady 15 s 650° C. 4 SLPM N2 Ramp 10 s 900° C. 4 SLPM N2 Steady 55 s 950° C. 4 SLPM N2 Ramp 30 s 650° C. 7 SLPM N2 Delay 15 s N/A 7 SLPM N2 - The
sixth step 406 ofmethod 400 may include subjecting the diamond material to a pre-substitutional mask deposition over a portion of the diamond lattice. The pre-substitutional mask deposition may be an aluminum pre-implant mask deposition. The pre-substitutional mask deposition may be performed using a Gryphon Metal Sputter System using aluminum of 99.99999% (6N) purity, with a deposition time of 21-24 seconds, at a power of 7.5 kW, a pressure: 2.5×10−3 Torr; and to a thickness of 30 nm. - For some applications, it may be beneficial to differentially dope different parts of the same diamond wafer, for example, to create p-type and n-type regions. In embodiments, various semiconductor devices are created including P-N junctions and P-i-N junctions.
-
FIG. 5A andFIG. 5B show a block diagram of a third embodiment of themethod 500 for fabricating layers within diamond material.Method 500 provides a process for fabricating n-type layers within diamond semiconductors for a P+-i-N diode. The first step ofmethod 500 may be the same as thefirst step 102 ofmethod 100, which includes selecting a diamond material having a diamond lattice structure. -
FIG. 6 shows a top view of an exemplary model of a P+-i-N diode 600 that may be fabricated according tomethod 500. P+-i-N diode 600 may include a lightly doped semiconductor region (i) (for example, seeFIG. 8, 804 ), between a pt-type semiconductor region 608, and an n-type semiconductor region 606. The method of 500 with SRIM, Stopping and Range of ions in Matter, modeling provides a path for fabricating P+-i-N diodes that approach theoretical projections. In one embodiment, the P+-i-N diode 600 may include the lightly doped semiconductor region (i) 804 of a depth of approximately 10 nm, between a p-type semiconductor (for example, seeFIG. 8, 806 ) of a depth of approximately 150 nm, the p+-type semiconductor region 608 of a depth of approximately 100 nm, and the n-type semiconductor region 606 of a depth of approximately 100 nm. 6 also shows a metallic contact/bonding pad 604 for connecting to the p+-type semiconductor region 608. - The second step of
method 500 may be the same as thesecond step 402 ofmethod 400, including cleaning the diamond material to remove surface contaminants. - The
third step 502 ofmethod 500 may include subjecting the diamond material to a pre-P+ mask deposition over a non-P+ portion of the diamond lattice. The pre-P+ mask deposition may protect a non-P+ portion of the diamond material during P+ ion implantation. The pre-P+ mask deposition may be an aluminum pre-implant mask deposition. The pre-ion track mask deposition may be performed using a Gryphon Metal Sputter System using aluminum of 99.99999% (6N) purity, with a deposition time of 21-24 seconds, at a power of 7.5 kW, a pressure: 2.5×10−3 Torr; and to a thickness of 30 nm. - The
fourth step 504 ofmethod 500 may include a P+ layer implant of the diamond material. The P+ layer implant may be performed with a dopant of 11B+, at a beam current of 0.04 μA, at a beam energy of 55 keV, with a beam dose of 1×1020 atoms/cm2, at an incident angle of 6 degrees, and at or below approximately 78 degrees K, to create a P+ layer of 100 nm. - The fifth step of
method 500 may be the same as thesixth step 406 ofmethod 400, including mask etching, cleaning, and annealing the diamond material. - The
sixth step 506 ofmethod 500 may include subjecting the diamond material to a pre-P mask deposition over a non-P portion of the diamond lattice. The pre-P mask deposition may protect a non-P portion of the diamond material during P ion implantation. The pre-P mask deposition may be an aluminum pre-implant mask deposition. The pre-P mask deposition may be performed using a Gryphon Metal Sputter System using aluminum of 99.99999% (6N) purity, with a deposition time of 21-24 seconds, at a power of 7.5 kW, a pressure: 2.5×10−3 Torr; and to a thickness of 30 nm. - The
seventh step 508 ofmethod 500 may include a P layer implant of the diamond material. The P layer implant may be performed with a dopant of 11B+, at a beam current of 0.04 μA, at a beam energy of 55 keV, with a beam dose of 3×1017 atoms/cm2, at an incident angle of 6 degrees, and at or below approximately 78 degrees K, to create a P layer of 150 nm. - The eighth step of
method 500 may be the same as thesixth step 406 ofmethod 400, including mask etching, cleaning, and annealing the diamond material. - The ninth step of
method 500 may be the same as thethird step 404 ofmethod 400, including subjecting the diamond material to a pre-ion track mask deposition over a first portion of the diamond lattice. - The tenth step of
method 500 may be the same as thesecond step 104 ofmethod 100, which includes introducing a minimal amount of acceptor dopant atoms to the diamond lattice to create ion tracks. - The eleventh step of
method 500 may be the same as thethird step 106 ofmethod 100, which includes introducing substitutional dopant atoms to the diamond lattice through the ion tracks. - The twelfth step of
method 500 may be same as thesixth step 406 ofmethod 400, including mask etching, cleaning, and annealing the diamond material. - The
thirteenth step 510 ofmethod 500 may include a blanket etch. Thethirteenth step 510 may include a blanket etch in which the surface layer, approximately 25 nm, of thediamond layer 202 is etched off to remove any surface graphitization. - The
fourteenth step 512 ofmethod 500 may include a photolithography/mesa etch to obtain a diamond stack structure, such as that shown inFIG. 6 . Thefourteenth step 512 may include a diffusion clean and photolithography prior to the mesa etch. - The
fifteenth step 514 ofmethod 500 may include a creating a contact for the top of the stack. Contact to the top of the stack may be achieved by evaporating ITO with 5N purity to a thickness of 200 nm onto the stack through a shadow mask and then performing a liftoff. - The
sixteenth step 516 ofmethod 500 may include annealing. The annealing ofstep 516 may be oven annealing at 420 degrees C. in Ar ambient until ITO transparency is attained, which may be in approximately 2.5 hours. - The seventeenth step 518 of
method 500 may include creating ohmic contacts. The ohmic contacts may include contacts to the layer, for example, the metallic contact/bonding pad 604, and the n-layer. As wire bonding may be difficult with a small contact area, Ti and Au layers may be evaporated through a shadow mask using photolithography. Ti may also function as a diffusion barrier between ITO and Au layers. A contact layer thickness of 30 nm may be created for the P layer. A contact layer thickness of 200 nm may be created for the N-layer. In one embodiment, the diamond cap layer may be removed to expose the newly formed n-type layer to form an electrical contact for device use. The step may include polishing the diamond layer while etching, thus minimizing the surface roughness, and electrically terminating (oxygen) the surface of the diamond, a step in semiconductor device fabrication. In some embodiments, there is a further step of forming metal contacts on the diamond so that the diamond may function as a component part of an electronic device. The seventeenth step 518 ofmethod 500 may include a metal furnace annealing. The metal furnace annealing may be performed at 420 degrees celsius for two hours. - The eighteenth step 520 of
method 500 may include wafer surface termination. - The
nineteenth step 522 ofmethod 500 may include wafer surface dicing. - The
twentieth step 524 ofmethod 500 may include packaging. In the twentieth step 520, portions of the diamond material may be diced, mounted, wire bound and encapsulated in transparent silicone sealant to create 6-pin surface mount device packages. -
FIG. 7 shows a perspective view of a model of an exemplary six-pin surfacemount device package 700 that may be fabricated according to the method ofFIG. 5A andFIG. 5B . - The methods disclosed herein may allow for the creation of a number of electrical diamond junctions to serve functions traditionally served by silicon semiconductors. While the application discusses examples in the context of a bipolar diode, those having skill in the art will recognize that the present techniques describe novel genuine n-type diamond material and novel p-type diamond material that may be used in multiple variations of electrical devices and monolithically formed combinations of the variations, including FETs and other switches, digital and analog, and light emitting bodies, and are not limited to the specific implementations shown herein. The various preferred embodiments need not necessarily be separate from each other and can be combined.
-
FIG. 8 shows a schematic diagram of a P+-i-N diodetest condition setup 802. A P+-i-N diode, such as a P+-i-N diode 600 fabricated according tomethod 500, may be tested according to the P+-i-N diodetest condition setup 802. -
FIG. 9 is agraphical illustration 900 of the thresholdvoltage performance characteristics 902 of a P+-i-N diode that may be fabricated according tomethod 500. The thresholdvoltage performance characteristics 902 may be obtained based upon DC conditions using suitable resistor biasing, and RF′ conditions using suitable TTL drivers or hybrid wire configuration, at room temperature, 76 degrees F. by IR measurement, under both low field and high field conditions. The thresholdvoltage performance characteristics 902 indicates a threshold voltage and current levels similar to those theoretically predicted for diamond. -
FIG. 10 is agraphical illustration 1000 of the current-voltage characteristics of a P+-i-N diode, such as a P+-i-N diode 600 fabricated according tomethod 500, in forward bias, with the cathode negative, at room temperatures. A current-voltage curve 1002 shows the current-voltage characteristics for such a P+-i-N diode that may be fabricated according tomethod 500. The current-voltage curve 1002 indicates a large concentration of electrons are available for conduction at room temperatures. A lowvoltage depletion region 1004 of the current-voltage curve 1002 shows charge carriers are diffused from the N layer and the P layer into the intrinsic region, for example, charge carriers are diffused from the n-type semiconductor region 606 and the between a p+-type semiconductor region 608, into the lightly doped semiconductor region (i) 804. In the lightly doped semiconductor region (i) 804 the charge carriers may combine. Since recombination does not occur instantly, charge may be stored in the lightly doped semiconductor region (i) 804, thus lowering resistivity. - A
high injection region 1006 of the current-voltage curve 1002 shows that as an applied potential is increased, charge carriers may flood into the intrinsic region, for example the lightly doped semiconductor region (i) 804, resulting in a concentration of carriers in excess of equilibrium concentrations. Aseries resistance region 1008 of the current-voltage curve 1002 is also shown. -
FIG. 11 is agraphical illustration 1100 of the current density characteristics of a P+-i-N diode, such as a P+-i-N diode 600 fabricated according tomethod 500, in forward bias, with the cathode negative, at room temperatures. Acurrent density curve 1102 shows the current density characteristics for such a P+-i-N diode that may be fabricated according tomethod 500. Thecurrent density curve 1102 shows a concentration of charge carrier types at current densities of greater than 1600 Amperes/cm2 at 5 V. -
FIG. 12 is agraphical illustration 1200 of the current-voltage characteristics of a P+-i-N diode, such as a P+-i-N diode 600 fabricated according tomethod 500, in reverse bias, with the cathode positive, at room temperatures. A current-voltage curve 1202 shows the current-voltage characteristics for such a P+-i-N diode that may be fabricated according tomethod 500. The current-voltage curve 1202 shows that a small amount of reverse voltage may be required before the depletion region width becomes fully depleted of charge carriers and carrier diffusion ceases, as indicated by the small rise and rapid decrease in current levels. -
FIG. 13 is agraphical illustration 1300 of the current density characteristics of a P+-i-N diode, such as a P+-i-N diode 600 fabricated according tomethod 500, in reverse bias, with the cathode positive, at room temperatures. Acurrent density curve 1302 shows the current density characteristics for such a P+-i-N diode that may be fabricated according tomethod 500. Thecurrent density curve 1302 shows a a P+-i-N diode, such as a P+-i-N diode 600, is suited for signal attenuation, such as but not limited, to RI signal attenuation, as modulation is controllable. -
FIG. 14 shows a schematic illustration of an RF attenuatordriver chip configuration 1400, for use with a P+-i-N diode, such as a P+-i-N diode 600 fabricated according tomethod 500.RF attenuator 1400 may provide attenuation characteristics with Rload varying from approximately 10 KΩ to 1 mΩ, current controlled characteristic, at 77 KHz. - The systems and fabrication methods described herein provide a number of new and useful technologies, including novel n-type and novel p-type diamond semiconducting materials and devices, and methods for fabricating novel n-type and novel p-type diamond semiconducting materials and devices.
- The novel fabrication methods include, but are not limited to, those for creating, etching, and metalizing (Schottky and Ohmic) genuine quality n-type diamond material; creating Integrated. Circuits (ICs) and device drivers from diamond based power elements.
- The novel devices include, but are not limited to, n-type diamond semiconductors that are at least partially activated at room temperature—i.e., the device material has sufficient carrier concentration to activate and participate in conduction; n-type diamond with high electron mobility; n-type diamond which has both high carrier mobility and high carrier concentration—without requiring a high temperature (above room temperature) or the presence of a high electrical field; an n-type diamond semiconductor with an estimated electron mobility in excess of 1,000 cm2/Vs and a carrier concentration of approximately 1×1016 electrons/cm3 at room/ambient temperature; a bipolar diamond semiconductor device; devices with p-type and n-type regions on a single diamond wafer; diamond diode devices; bipolar diamond semiconductor devices carrying high current without necessitating either a high temperature or the presence of a strong electrical field; bipolar diamond semiconductor devices which can carry a one milliamp current while at room temperature and in the presence of a 0.28V electrical field; an n-type diamond material on polycrystalline diamond; a low cost thin film polycrystalline diamond-on-silicon carrier; diamond semiconductors on other carrier types (e.g., Fused Silica, Quartz, Sapphire, Silicon Oxide or other Oxides, etc.); a diamond power RF attenuator, a polycrystalline diamond power RF attenuator chip, a polycrystalline diamond power RF attenuator device; a diamond light emitting diode or/laser diode (LED); monolithically integrate diamond based logic drivers with high power elements (e.g., LED) on the same chip; n-type diamond material which is stable in the presence of oxygen (i.e., if a non-negligible amount of oxygen is present on the surface (such as when the wafer is on open air) the n-type semiconductor's conductivity and performance continue).
- In some embodiments, this n-type and novel p-type diamond semiconducting material is constructed using polycrystalline diamond having less than a micrometer size grain and with doped thin film layers having sizes on the order of less than 900 nm. The techniques for forming said diamond material may be used on diamond films with diamond grain boundaries that are nearly atomic abrupt, such that uniformity of electrical performance may be maintained, while enabling the ability to form thin-film features from said material.
- Another aspect of the invention is the ability to create metal contacts attached to the diamond semiconducting material, including the n-type material. Said metal contacts attach to the diamond material and continue to have good/ohmic conductivity (e.g., displaying high linearity). Metal contacts may refer to either or both metals (e.g., Au, Ag, Al, Ti, Pd, Pt, etc.) or transparent metals (e.g., indium tin oxide, fluoride tin oxide, etc.), as warranted by desired application use.
- The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment or variant described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments or variants. All of the embodiments and variants described in this description are exemplary embodiments and variants provided to enable persons skilled in the art to make and use the invention, and not necessarily to limit the scope of legal protection afforded the appended claims.
- The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use that which is defined by the appended claims. The following claims are not intended to be limited to the disclosed embodiments. Other embodiments and modifications will readily occur to those of ordinary skill in the art in view of these teachings. Therefore, the following claims are intended to cover all such embodiments and modifications when viewed in conjunction with the above specification and accompanying drawings.
Claims (16)
1. (canceled)
2. (canceled)
3. (canceled)
4. (canceled)
5. A method of fabricating diamond semiconductors, the method including the steps of:
selecting a diamond material having a diamond lattice, forming a diamond layer on a silicon dioxide layer;
introducing acceptor dopant atoms to the diamond lattice to create pathways;
introducing substitutional dopant atoms to the diamond lattice through the pathways; and
annealing the diamond lattice to remove the pathways;
wherein the introduction of the acceptor dopant atoms does not create a critical density of more than 1022/cm3 of vacancies in the diamond layer.
6. The method of claim 5 , wherein the diamond material is intrinsic diamond.
7. The method of claim 5 , wherein the acceptor dopant atoms are introduced at 293 to 298 degrees Kelvin.
8. The method of claim 5 , wherein the acceptor dopant, atoms are boron.
9. The method of claim 5 , wherein the amount of acceptor dopant atoms is between 5×108/cm2 and 5×1010/cm2.
10. The method of claim 5 , wherein the substitutional dopant atoms are introduced at or below 78 degrees Kelvin.
11. The method of claim 5 , wherein the substitutional dopant atoms are introduced at less than 500 keV.
12. The method of claim 5 , wherein the substitutional dopant atoms are introduced at less than 140 keV and at a 6 degree offset.
13. The method of claim 5 , wherein the substitutional dopant atoms are phosphorus.
14. The method of claim 5 , wherein the substitutional dopant atoms are introduced at a concentration greater than 9×1017/cm3.
15. The method of claim 5 , wherein the annealing takes place at or above 1000 degrees Celsius.
16. A semiconductor fabricated according to the method of claim 5 .
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US15/706,751 US20180068853A1 (en) | 2011-07-30 | 2017-09-17 | Diamond Semiconductor System and Method |
US16/459,579 US20200066527A1 (en) | 2011-07-30 | 2019-07-01 | Diamond Semiconductor System and Method |
US17/329,117 US11784048B2 (en) | 2011-07-30 | 2021-05-24 | Diamond semiconductor system and method |
US18/467,208 US20240071763A1 (en) | 2011-07-30 | 2023-09-14 | Diamond Semiconductor System and Method |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US201161513569P | 2011-07-30 | 2011-07-30 | |
US13/273,467 US20130026492A1 (en) | 2011-07-30 | 2011-10-14 | Diamond Semiconductor System and Method |
US14/581,030 US20150108505A1 (en) | 2011-07-30 | 2014-12-23 | Diamond Semiconductor System and Method |
US15/706,751 US20180068853A1 (en) | 2011-07-30 | 2017-09-17 | Diamond Semiconductor System and Method |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/581,030 Continuation US20150108505A1 (en) | 2011-07-30 | 2014-12-23 | Diamond Semiconductor System and Method |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US16/459,579 Continuation US20200066527A1 (en) | 2011-07-30 | 2019-07-01 | Diamond Semiconductor System and Method |
Publications (1)
Publication Number | Publication Date |
---|---|
US20180068853A1 true US20180068853A1 (en) | 2018-03-08 |
Family
ID=47596502
Family Applications (6)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/273,467 Abandoned US20130026492A1 (en) | 2011-07-30 | 2011-10-14 | Diamond Semiconductor System and Method |
US14/581,030 Abandoned US20150108505A1 (en) | 2011-07-30 | 2014-12-23 | Diamond Semiconductor System and Method |
US15/706,751 Abandoned US20180068853A1 (en) | 2011-07-30 | 2017-09-17 | Diamond Semiconductor System and Method |
US16/459,579 Abandoned US20200066527A1 (en) | 2011-07-30 | 2019-07-01 | Diamond Semiconductor System and Method |
US17/329,117 Active US11784048B2 (en) | 2011-07-30 | 2021-05-24 | Diamond semiconductor system and method |
US18/467,208 Pending US20240071763A1 (en) | 2011-07-30 | 2023-09-14 | Diamond Semiconductor System and Method |
Family Applications Before (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/273,467 Abandoned US20130026492A1 (en) | 2011-07-30 | 2011-10-14 | Diamond Semiconductor System and Method |
US14/581,030 Abandoned US20150108505A1 (en) | 2011-07-30 | 2014-12-23 | Diamond Semiconductor System and Method |
Family Applications After (3)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US16/459,579 Abandoned US20200066527A1 (en) | 2011-07-30 | 2019-07-01 | Diamond Semiconductor System and Method |
US17/329,117 Active US11784048B2 (en) | 2011-07-30 | 2021-05-24 | Diamond semiconductor system and method |
US18/467,208 Pending US20240071763A1 (en) | 2011-07-30 | 2023-09-14 | Diamond Semiconductor System and Method |
Country Status (7)
Country | Link |
---|---|
US (6) | US20130026492A1 (en) |
EP (1) | EP2737112B1 (en) |
JP (4) | JP6195831B2 (en) |
KR (2) | KR102007051B1 (en) |
CN (2) | CN114420747A (en) |
TW (2) | TWI557776B (en) |
WO (1) | WO2013019435A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11522055B2 (en) * | 2018-01-15 | 2022-12-06 | National Institute Of Advanced Industrial Science And Technology | Stack comprising single-crystal diamond substrate |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR3004853B1 (en) * | 2013-04-22 | 2016-10-21 | Centre Nat Rech Scient | METHOD FOR MANUFACTURING A SCHOTTKY DIODE ON A DIAMOND SUBSTRATE |
US9441940B2 (en) | 2015-01-21 | 2016-09-13 | Uchicago Argonne, Llc | Piezoresistive boron doped diamond nanowire |
US9484474B1 (en) | 2015-07-02 | 2016-11-01 | Uchicago Argonne, Llc | Ultrananocrystalline diamond contacts for electronic devices |
US9741561B2 (en) | 2015-07-10 | 2017-08-22 | Uchicago Argonne, Llc | Transparent nanocrystalline diamond coatings and devices |
US20200000595A1 (en) | 2016-06-07 | 2020-01-02 | HD LifeSciences LLC | High X-Ray Lucency Lattice Structures |
US11253368B2 (en) * | 2017-02-14 | 2022-02-22 | Nanohive Medical Llc | Methods of designing high x-ray lucency lattice structures |
EP4331842A3 (en) | 2017-04-01 | 2024-05-29 | Nanohive Medical LLC | Three-dimensional lattice structures for implants |
US11291558B2 (en) | 2018-07-26 | 2022-04-05 | Nanohive Medical Llc | Dynamic implant fixation plate |
US11497617B2 (en) | 2019-01-16 | 2022-11-15 | Nanohive Medical Llc | Variable depth implants |
CN110565066B (en) * | 2019-09-17 | 2022-04-19 | 北京阿尔玛斯科技有限公司 | Co-doped diamond, preparation method thereof, semiconductor material and device |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5994208A (en) * | 1995-06-23 | 1999-11-30 | Prins; Johan Frans | Doping in crystalline diamond substrates |
US20110005942A1 (en) * | 2008-02-28 | 2011-01-13 | Universitat Ulm | Iii-v nitride semiconductor device comprising a diamond layer |
US20130153931A1 (en) * | 2010-09-02 | 2013-06-20 | Board Of Trustees Of Michigan State University | N-doped single crystal diamond substrates and methods therefor |
Family Cites Families (21)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
IL79107A (en) | 1985-06-17 | 1989-03-31 | De Beers Ind Diamond | Ion implantation in crystalline substrate |
US5051785A (en) * | 1989-06-22 | 1991-09-24 | Advanced Technology Materials, Inc. | N-type semiconducting diamond, and method of making the same |
US5298106A (en) * | 1991-07-08 | 1994-03-29 | The United States Of America As Represented By The Secretary Of The Navy | Method of doping single crystal diamond for electronic devices |
ZA933939B (en) | 1992-06-05 | 1993-12-30 | De Beers Ind Diamond | Diamond doping |
JPH0648715A (en) * | 1992-07-24 | 1994-02-22 | Matsushita Electric Ind Co Ltd | Production of semiconductor diamond |
JP4071833B2 (en) * | 1993-09-10 | 2008-04-02 | 住友電気工業株式会社 | Diamond semiconductor device |
US5653800A (en) * | 1995-08-03 | 1997-08-05 | Eneco, Inc. | Method for producing N-type semiconducting diamond |
JP3138705B1 (en) | 1999-08-31 | 2001-02-26 | 工業技術院長 | Diamond pn junction diode and method of manufacturing the same |
DE60135653D1 (en) * | 2000-06-15 | 2008-10-16 | Element Six Pty Ltd | CRYSTAL DIAMOND MANUFACTURED BY CVD |
IL153381A0 (en) * | 2000-06-15 | 2003-07-06 | Element Six Pty Ltd | Thick single cyrstal diamond layer, method for making it and gemstones produced from the layer |
FR2848335B1 (en) * | 2002-12-06 | 2005-10-07 | Centre Nat Rech Scient | PROCESS FOR THE PREPARATION OF HIGH-CONDUCTIVITY N-TYPE DIAMOND DIAMOND |
JP2004214264A (en) * | 2002-12-27 | 2004-07-29 | Sumitomo Electric Ind Ltd | LOW-RESISTANCE n-TYPE SEMICONDUCTOR DIAMOND AND ITS MANUFACTURING METHOD |
GB0318215D0 (en) * | 2003-08-04 | 2003-09-03 | Element Six Ltd | Diamond microelectrodes |
GB0508889D0 (en) * | 2005-04-29 | 2005-06-08 | Element Six Ltd | Diamond transistor and method of manufacture thereof |
DE112007001892T5 (en) * | 2006-08-11 | 2009-06-10 | Akhan Technologies, Inc., Schaumburg | Nanocrystalline diamond P-channel field effect transistor |
WO2008021482A2 (en) * | 2006-08-14 | 2008-02-21 | Chien-Min Sung | Diamond-like carbon electronic devices and methods of manufacture |
WO2009005134A1 (en) * | 2007-07-04 | 2009-01-08 | National Institute For Materials Science | Diamond semiconductor device |
US7888171B2 (en) * | 2008-12-22 | 2011-02-15 | Raytheon Company | Fabricating a gallium nitride layer with diamond layers |
JP2010189208A (en) * | 2009-02-16 | 2010-09-02 | Nippon Telegr & Teleph Corp <Ntt> | Diamond semiconductor and method for producing the same |
DE102009033652A1 (en) * | 2009-07-17 | 2011-01-27 | Universität Ulm | Semiconductor device with diamond-containing electrodes and its use |
CN102214574B (en) * | 2010-04-07 | 2013-06-12 | 中国科学院微电子研究所 | Method for manufacturing semiconductor device |
-
2011
- 2011-10-14 US US13/273,467 patent/US20130026492A1/en not_active Abandoned
-
2012
- 2012-07-20 WO PCT/US2012/047673 patent/WO2013019435A1/en unknown
- 2012-07-20 KR KR1020147004858A patent/KR102007051B1/en active IP Right Grant
- 2012-07-20 CN CN202111546963.8A patent/CN114420747A/en active Pending
- 2012-07-20 KR KR1020197022269A patent/KR102195950B1/en active IP Right Grant
- 2012-07-20 JP JP2014522910A patent/JP6195831B2/en active Active
- 2012-07-20 EP EP12820625.7A patent/EP2737112B1/en active Active
- 2012-07-20 CN CN201280038078.1A patent/CN103717791B/en active Active
- 2012-07-27 TW TW101127330A patent/TWI557776B/en active
- 2012-07-27 TW TW105127717A patent/TWI659458B/en active
-
2014
- 2014-12-23 US US14/581,030 patent/US20150108505A1/en not_active Abandoned
-
2017
- 2017-08-16 JP JP2017156973A patent/JP6580644B2/en active Active
- 2017-09-17 US US15/706,751 patent/US20180068853A1/en not_active Abandoned
-
2019
- 2019-07-01 US US16/459,579 patent/US20200066527A1/en not_active Abandoned
- 2019-08-27 JP JP2019154334A patent/JP6898400B2/en active Active
-
2021
- 2021-05-24 US US17/329,117 patent/US11784048B2/en active Active
- 2021-06-10 JP JP2021096979A patent/JP7443288B2/en active Active
-
2023
- 2023-09-14 US US18/467,208 patent/US20240071763A1/en active Pending
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5994208A (en) * | 1995-06-23 | 1999-11-30 | Prins; Johan Frans | Doping in crystalline diamond substrates |
US20110005942A1 (en) * | 2008-02-28 | 2011-01-13 | Universitat Ulm | Iii-v nitride semiconductor device comprising a diamond layer |
US20130153931A1 (en) * | 2010-09-02 | 2013-06-20 | Board Of Trustees Of Michigan State University | N-doped single crystal diamond substrates and methods therefor |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11522055B2 (en) * | 2018-01-15 | 2022-12-06 | National Institute Of Advanced Industrial Science And Technology | Stack comprising single-crystal diamond substrate |
Also Published As
Publication number | Publication date |
---|---|
US20220013361A1 (en) | 2022-01-13 |
US20200066527A1 (en) | 2020-02-27 |
JP7443288B2 (en) | 2024-03-05 |
CN103717791B (en) | 2021-12-28 |
KR102007051B1 (en) | 2019-08-02 |
JP2017224845A (en) | 2017-12-21 |
KR20140068894A (en) | 2014-06-09 |
US11784048B2 (en) | 2023-10-10 |
JP6580644B2 (en) | 2019-09-25 |
JP2021168389A (en) | 2021-10-21 |
CN114420747A (en) | 2022-04-29 |
TW201310506A (en) | 2013-03-01 |
EP2737112A1 (en) | 2014-06-04 |
JP2020074356A (en) | 2020-05-14 |
KR102195950B1 (en) | 2020-12-30 |
TWI557776B (en) | 2016-11-11 |
CN103717791A (en) | 2014-04-09 |
JP2014527715A (en) | 2014-10-16 |
US20240071763A1 (en) | 2024-02-29 |
EP2737112A4 (en) | 2015-03-25 |
WO2013019435A1 (en) | 2013-02-07 |
US20130026492A1 (en) | 2013-01-31 |
JP6195831B2 (en) | 2017-09-13 |
EP2737112B1 (en) | 2020-02-26 |
JP6898400B2 (en) | 2021-07-07 |
US20150108505A1 (en) | 2015-04-23 |
TWI659458B (en) | 2019-05-11 |
KR20190094476A (en) | 2019-08-13 |
TW201643943A (en) | 2016-12-16 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US11784048B2 (en) | Diamond semiconductor system and method | |
US11915934B2 (en) | Diamond semiconductor system and method | |
US11107684B2 (en) | Diamond semiconductor system and method | |
JP2021168389A5 (en) | ||
JP2014527715A5 (en) |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STPP | Information on status: patent application and granting procedure in general |
Free format text: FINAL REJECTION MAILED |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |