CN113622027B - High-resistance gallium oxide crystal and preparation method and application thereof - Google Patents

High-resistance gallium oxide crystal and preparation method and application thereof Download PDF

Info

Publication number
CN113622027B
CN113622027B CN202110825757.4A CN202110825757A CN113622027B CN 113622027 B CN113622027 B CN 113622027B CN 202110825757 A CN202110825757 A CN 202110825757A CN 113622027 B CN113622027 B CN 113622027B
Authority
CN
China
Prior art keywords
gallium oxide
crystal
oxide crystal
resistivity
powder
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.)
Active
Application number
CN202110825757.4A
Other languages
Chinese (zh)
Other versions
CN113622027A (en
Inventor
唐慧丽
李志伟
刘波
徐军
罗平
吴锋
王庆国
张超逸
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Tongji University
Original Assignee
Tongji University
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Tongji University filed Critical Tongji University
Priority to CN202110825757.4A priority Critical patent/CN113622027B/en
Publication of CN113622027A publication Critical patent/CN113622027A/en
Application granted granted Critical
Publication of CN113622027B publication Critical patent/CN113622027B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/10—Inorganic compounds or compositions
    • C30B29/16—Oxides
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B11/00—Single-crystal growth by normal freezing or freezing under temperature gradient, e.g. Bridgman-Stockbarger method
    • C30B11/04—Single-crystal growth by normal freezing or freezing under temperature gradient, e.g. Bridgman-Stockbarger method adding crystallising materials or reactants forming it in situ to the melt
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B13/00—Single-crystal growth by zone-melting; Refining by zone-melting
    • C30B13/08—Single-crystal growth by zone-melting; Refining by zone-melting adding crystallising materials or reactants forming it in situ to the molten zone
    • C30B13/10—Single-crystal growth by zone-melting; Refining by zone-melting adding crystallising materials or reactants forming it in situ to the molten zone with addition of doping materials
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B15/00—Single-crystal growth by pulling from a melt, e.g. Czochralski method
    • C30B15/02—Single-crystal growth by pulling from a melt, e.g. Czochralski method adding crystallising materials or reactants forming it in situ to the melt
    • C30B15/04—Single-crystal growth by pulling from a melt, e.g. Czochralski method adding crystallising materials or reactants forming it in situ to the melt adding doping materials, e.g. for n-p-junction
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B15/00—Single-crystal growth by pulling from a melt, e.g. Czochralski method
    • C30B15/34—Edge-defined film-fed crystal-growth using dies or slits
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/02—Details
    • H01L31/0224—Electrodes
    • H01L31/022408—Electrodes for devices characterised by at least one potential jump barrier or surface barrier
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/0248—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies
    • H01L31/0256—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies characterised by the material
    • H01L31/0264—Inorganic materials
    • H01L31/032—Inorganic materials including, apart from doping materials or other impurities, only compounds not provided for in groups H01L31/0272 - H01L31/0312
    • H01L31/0321—Inorganic materials including, apart from doping materials or other impurities, only compounds not provided for in groups H01L31/0272 - H01L31/0312 characterised by the doping material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/08—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof in which radiation controls flow of current through the device, e.g. photoresistors
    • H01L31/10—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof in which radiation controls flow of current through the device, e.g. photoresistors characterised by potential barriers, e.g. phototransistors
    • H01L31/115—Devices sensitive to very short wavelength, e.g. X-rays, gamma-rays or corpuscular radiation

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Metallurgy (AREA)
  • Materials Engineering (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • General Physics & Mathematics (AREA)
  • Power Engineering (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Computer Hardware Design (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Inorganic Chemistry (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)

Abstract

The invention relates to a high-resistance gallium oxide crystal and a preparation method and application thereof, wherein the molecular formula of the high-resistance gallium oxide crystal is beta- (Ga) 1‑x Al x ) 2 O 3 Wherein the value range of x is more than or equal to 0.07 and less than or equal to 0.3, and the crystal is prepared by a melt growth method comprising an optical floating zone method, a pulling method, a guide die method or a descent method. Compared with the prior art, the resistivity of the aluminum-doped high-resistance gallium oxide crystal provided by the invention is more than or equal to 10 9 Omega cm, high crystal crystallization quality, and the radiation detector prepared based on the high-resistance gallium oxide crystal has the advantages of simple manufacturing process, small dark current, high light-dark current ratio, high response speed, high sensitivity, high signal-to-noise ratio, good energy resolution ratio and the like.

Description

High-resistance gallium oxide crystal and preparation method and application thereof
Technical Field
The invention belongs to the field of semiconductor crystal materials and nuclear radiation detectors, and particularly relates to a high-resistance gallium oxide crystal and a preparation method and application thereof.
Background
Gallium oxide (. Beta. -Ga) 2 O 3 ) The crystal is a novel ultra-wide bandgap semiconductor material, and has the advantages of large forbidden band width (4.8 eV), high theoretical breakdown field strength (8 MV/cm) and radiation resistanceThe advantages of strong radiation capability and the like have attracted much attention in recent years. Unintentionally doped gallium oxide crystals have a low resistivity due to shallow donors formed in the crystal by impurities such as Si, sn, ge, etc. remaining in the raw material, resulting in a crystal having a certain concentration of free electrons. The X-ray radiation detection device prepared by using the unintentionally doped gallium oxide crystal has higher dark current, reduces the core parameters of the device such as light-dark current ratio, sensitivity and the like, and seriously influences the use of the detection device (such as 'Schottky X-ray detectors based on a bulk beta-Ga') 2 O 3 substrate”,Applied Physics Letters 112,103502,2018)。
In the field of nuclear radiation detection, in order to make a semiconductor detection device have excellent performances such as high light-dark current ratio, high sensitivity, high signal-to-noise ratio, high energy resolution and the like, a high-resistance semiconductor material is required to be used for reducing the dark current of the device and improving the detection limit. For gallium oxide crystals, magnesium ions, iron ions, calcium ions and zinc ions doped with the gallium oxide crystal can play an acceptor compensation role, and the concentration of free electrons in the crystal is reduced, so that gallium oxide crystals with higher resistivity or semi-insulation are obtained (patent CN 109537055A). However, these commonly used acceptor-compensated doped ions and gallium do not belong to the same group of elements, the difference of electronic structure is large, and after the impurity elements are doped, the lattice of the gallium oxide crystal is greatly distorted, which affects the crystallization quality of the high-resistance gallium oxide crystal.
Patent CN 113035999A discloses an Al-doped gallium oxide X-ray detector and a preparation method thereof, the patent reduces the carrier concentration in the Al-doped gallium oxide single crystal by means of high-temperature annealing at 1250-1600 ℃ in air or oxygen atmosphere, and does not obtain high-resistance gallium oxide crystal by adjusting the doping concentration of Al ions; this patent uses the X-ray detector of interdigital electrode preparation because the electric field depth is less than X ray's penetration depth far away, and most photogenerated electron hole pair can't be collected by the electrode, causes the carrier collection efficiency low, and the photocurrent of detector is not high, and the surface defect of crystal can produce a large amount of leakage currents moreover, leads to the dark current of detector to improve, is unfavorable for the device and is applied to low dose rate and surveys.
Disclosure of Invention
The invention aims to overcome the defects that the high-resistance gallium oxide crystal obtained by doping the foreign elements easily causes larger lattice distortion, has lower crystal quality and causes the reduction of electron mobility, and provides the high-resistance gallium oxide crystal and a preparation method and application thereof.
The resistivity of the aluminum-doped high-resistance gallium oxide crystal provided by the invention is more than or equal to 10 9 Omega cm, high crystal crystallization quality, and the radiation detector prepared based on the high-resistance gallium oxide crystal has the advantages of simple manufacturing process, small dark current, high light-dark current ratio, high response speed, high sensitivity, high signal-to-noise ratio, good energy resolution ratio and the like.
The purpose of the invention is realized by the following technical scheme:
a high-resistance gallium oxide crystal with a molecular formula of beta- (Ga) 1-x Al x ) 2 O 3 Wherein the value range of x is more than or equal to 0.07 and less than or equal to 0.3, the value range of x has important influence on obtaining high-resistance gallium oxide crystal with excellent performance, when the value of x is less than 0.07, the gallium oxide crystal has higher carrier concentration, and the resistivity of the crystal is lower; when the value of x is more than 0.3, the quality of the gallium oxide crystal is seriously deteriorated.
The aluminum and the gallium belong to the same group elements, have quite similar electronic structures, and the ionic radii are close, so that the aluminum ions cannot cause larger lattice distortion of the gallium oxide crystal when being doped, and therefore, the aluminum ions with higher concentration can be doped in the gallium oxide crystal. The principle of increasing the resistivity of gallium oxide crystals by doping aluminum ions is as follows: the valence band top of the gallium oxide crystal is determined by O2p state, the conduction band bottom is determined by Ga4s state, and after doping aluminum ions, the valence band spectrum test obtains beta- (Ga) 1-x Al x ) 2 O 3 The top position of the valence band of the crystal is not intentionally doped with beta-Ga 2 O 3 The crystals are kept uniform, beta- (Ga) 1-x Al x ) 2 O 3 The valence band top of the crystal is still determined by the O2p state, so that the doping of aluminum ions does not cause obvious change to the position of the valence band top of the gallium oxide crystal. However, beta- (Ga) 1-x Al x ) 2 O 3 The conduction band of the crystal is influenced by the Al3s state, and the conduction band is far from the bottomMoving in the direction away from the valence band, resulting in beta- (Ga) 1-x Al x ) 2 O 3 The forbidden band width of the crystal is increased, resulting in beta- (Ga) 1-x Al x ) 2 O 3 The distance from the bottom of the crystal conduction band to the donor level is increased, that is, the depth of the trap of the donor level is increased, and the capability of the donor level to supply electrons to the conduction band is suppressed, so that beta- (Ga) 1-x Al x ) 2 O 3 The free electron concentration of the crystal is greatly reduced, and the resistivity of the gallium oxide crystal is obviously improved. The high-resistance gallium oxide crystal provided by the invention has the resistivity up to 10 at room temperature 9 -10 12 Omega cm, and the forbidden band width is 4.9eV-5.3eV.
The preparation method of the high-resistance gallium oxide crystal can adopt melt growth methods such as an optical floating zone method, a pulling method, a mold guiding method, a descent method and the like, and the preferable preparation steps are as follows:
(1) Taking Ga 2 O 3 Powder with Al 2 O 3 Powder, accurately weighing the raw material powder according to a molecular formula, uniformly mixing, performing compression molding in a hydraulic or isostatic pressing mode, and performing high-temperature solid-phase sintering to synthesize the aluminum-doped gallium oxide polycrystal material;
(2) The polycrystalline raw material is loaded into an iridium crucible or a platinum-rhodium crucible or fixed on an upper rotating rod of an optical float zone furnace.
(3) And fixing the directional seed crystal on the seed crystal rod.
(4) And growing the aluminum-doped gallium oxide crystal by adopting an optical floating zone method, a pulling method, a mode guiding method and a descending method.
Ga as described in step (1) 2 O 3 The powder purity is preferably 4N-6N 2 O 3 The purity of the powder is preferably 4N-5N, the content of impurities in the high-purity raw material is less, and the problems of reduction of the resistivity of crystals, poor crystal quality and the like caused by the impurities can be avoided.
When the pulling method, the guide die method or the descent method is adopted in the step (2), an iridium or platinum-rhodium alloy crucible and carbon dioxide or a mixed atmosphere consisting of carbon dioxide and argon are adopted; when the optical floating zone method is adopted for growth, an air atmosphere or a pure oxygen atmosphere is adopted, and the gas flow rate is preferably 1-5L/min.
The invention also provides an application of the high-resistance gallium oxide crystal in a semiconductor radiation detection device, and a radiation detector prepared based on the high-resistance gallium oxide crystal adopts a double-sided symmetrical electrode structure.
The high-resistance gallium oxide crystal is cut and subjected to double-sided chemical mechanical polishing, the thickness of a wafer is 0.4-4mm, and the wafer thickness is less than 0.4mm, so that high-energy rays cannot be completely absorbed, and the photocurrent of a radiation detector is reduced; the wafer thickness is larger than 4mm, so that the capture probability in the carrier transport process is increased, the carrier collection efficiency of the detector is reduced, and the photocurrent is reduced.
The double-sided symmetrical electrode of the detector is a Ti/Au double-layer metal electrode, the thickness of the Ti layer is 5-50nm, the thickness of the Au layer is 50-100nm, the electrode is circular or rectangular, and the area of the electrode is 1-30mm 2 。
Compared with the prior art, the invention has the following advantages:
(1) Compared with the doping of iron, magnesium and other foreign elements, the doping of aluminum ions can further increase the forbidden bandwidth while improving the resistivity of the gallium oxide crystal, and can not cause serious distortion of the crystal lattice of the gallium oxide crystal due to aluminum doping, so that the obtained high-resistance gallium oxide crystal has high crystal quality.
(2) Compared with the prior art patent CN 113035999A, the invention reduces the back bottom carrier concentration of the gallium oxide crystal by limiting the Al ion doping concentration, thereby realizing the high resistance of the gallium oxide crystal; compared with a low-resistivity gallium oxide crystal, the semiconductor radiation detector prepared from the high-resistivity gallium oxide crystal provided by the invention has the remarkable advantages of low dark current, high optical dark current ratio, high response speed (both the rise time and the fall time are less than 0.05 s) and the like, the detection sensitivity is far higher than that of a commercial amorphous selenium X-ray detector, and the energy resolution is equivalent to that of a tellurium-zinc-cadmium gamma-ray detector.
(3) Compared with the radiation detector adopting the interdigital electrode in the prior art patent CN 113035999A, the radiation detector adopts the double-sided electrode, and has the advantages of simple device preparation process, capability of completely absorbing high-energy rays, high carrier collection efficiency, small influence of surface leakage current and the like.
Drawings
FIG. 1 shows example 1. Beta. - (Ga) 0.85 Al 0.15 ) 2 O 3 And cutting the polished crystal photo.
FIG. 2 shows β - (Ga) 1-x Al x ) 2 O 3 And x =0.05, 0.1, 0.15 transmission spectrum of the crystal.
FIG. 3 shows β - (Ga) 1-x Al x ) 2 O 3 And x =0.05, 0.1, 0.15 forbidden band width spectrum of the crystal.
FIG. 4 shows β - (Ga) 1-x Al x ) 2 O 3 Energy band diagram of the crystal.
FIG. 5 shows β - (Ga) 1-x Al x ) 2 O 3 Crystal resistivity versus x.
FIG. 6 shows a graph based on β - (Ga) 1-x Al x ) 2 O 3 A structure diagram of a radiation detection device for a crystal;
1-Au,2-Ti, 3-beta- (Ga) in FIG. 6 1-x Al x ) 2 O 3 Crystal, 4-Ti,5-Au.
FIG. 7 shows a graph based on β - (Ga) 0.85 Al 0.15 ) 2 O 3 Dark current and photocurrent of a radiation detector of the crystal.
FIG. 8 shows a graph based on β - (Ga) 0.85 Al 0.15 ) 2 O 3 The time response of a radiation detector of a crystal to X-rays at different voltages.
FIG. 9 shows β - (Ga) 0.95 Al 0.05 ) 2 O 3 I-V curve of the crystal.
Detailed Description
The invention is described in detail below with reference to the figures and specific embodiments.
Example 1:
growth of beta- (Ga) by optical floating zone method 0.85 Al 0.15 ) 2 O 3 And (4) crystals.
Ga is weighed according to the molar ratio of 0.85 2 O 3 Powder and Al 2 O 3 Grinding the powder for 60 min to mix the powder uniformly, and mixing the uniformly mixed powderA long rubber tube is filled into the raw material rod by using a funnel to prepare a raw material rod, the raw material rod is pressed by using a cold isostatic press under the pressure of 50MPa, and the raw material rod is placed into a muffle furnace to be sintered for 20 hours at the temperature of 1450 ℃ in the air to prepare a ceramic raw material rod. Growing crystals in an optical floating zone furnace in a flowing air atmosphere, mounting the raw material rod on an upper rotating rod,<010>the seed crystal in the direction is fixed on the lower rotating rod, the voltage is slowly increased to heat the seed crystal and the raw material rod, the growth speed of the crystal is 3mm/h, the rotating speed is 14rpm, the air flow rate is 3L/min, the temperature is slowly reduced to the room temperature after the growth is finished, the crystal is taken out, and the crystal is colorless and transparent and has no cracks. Cutting and polishing the crystal to obtain 5 × 5 × 1mm 3 As shown in fig. 1. (Ga) 0.85 Al 0.15 ) 2 O 3 Diffraction peak of crystal XRD pattern and beta-Ga 2 O 3 The standard cards are consistent. Beta- (Ga) 1-x Al x ) 2 O 3 The transmission spectra of x =0.05, 0.1, and 0.15 crystals are shown in fig. 2, and free electrons cause plasma reflection, thereby reducing the transmittance in the infrared band, β - (Ga) 0.85 Al 0.15 ) 2 O 3 The crystal has no obvious absorption in infrared band, which indicates that the free electron concentration of the crystal is extremely low. As can be seen from FIG. 3, β - (Ga) 0.85 Al 0.15 ) 2 O 3 The forbidden band width of the crystal is 5.11eV, and the forbidden band width of the gallium oxide crystal is increased after aluminum doping. Beta- (Ga) 0.85 Al 0.15 ) 2 O 3 The valence band spectrum test of the crystal obtains the top position of the valence band and beta-Ga 2 O 3 The crystals remained consistent, indicating that the aluminum doping did not alter the beta-Ga 2 O 3 The position of the top of the valence band of the crystal. After doping with aluminium ions, beta-Ga 2 O 3 The top of the conduction band of the crystal moves up, away from the original shallow donor, and the ability of the donor level to donate a free electron to the conduction band at room temperature is suppressed. FIG. 4 shows β - (Ga) 1-x Al x ) 2 O 3 Band diagram of crystal, wherein E c Is the conduction band energy level, E v Is the valence band energy level, E D Is a donor level, E F At Fermi level, beta- (Ga) 0.85 Al 0.15 ) 2 O 3 The position of the conduction band bottom of the crystal is higher than that of beta-Ga 2 O 3 Crystal, donor level ratio beta-Ga 2 O 3 Deeper in the crystal. FIG. 5 shows resistivity measurements of beta- (Ga) 1- x Al x ) 2 O 3 Graph of crystal resistivity vs. x, beta- (Ga) 0.85 Al 0.15 ) 2 O 3 The resistivity of the crystal is 1.5X 10 12 Omega cm. Preparation of a catalyst based on beta- (Ga) 0.85 Al 0.15 ) 2 O 3 A radiation detector of a crystal is characterized in that square Ti/Au electrodes are respectively deposited on the upper surface and the lower surface of the crystal, the thickness of the square Ti/Au electrodes is 20nm/50nm, the side length of the square Ti/Au electrodes is 3mm, and the structure of the detector is shown in figure 6. The X-ray detection performance of the radiation detector is tested by using an X-ray source with the tube voltage of 50 kV. FIG. 7 shows that the photo-dark current ratio of the detector is as high as 700 when the X-ray dose rate is 0.15Gy/s and the device voltage is 200V. FIG. 8 shows the response of the detector under different voltages when the X-ray dose rate is 9.8 μ Gy/s, and the result shows that the response speed of the detector is extremely fast, and the rise time and the fall time are both less than 0.05s; when the voltage is 350V, the detection sensitivity of the detector to X-rays is 851 mu C Gy -1 cm -2 42 times the sensitivity of a commercial amorphous selenium X-ray detector; the signal-to-noise ratio of the detectors under all the voltages is higher than 20, and the practical requirements are met. The response of the detector to gamma rays is tested by using gamma ray sources such as cesium-137, cobalt-60 and the like, and the energy resolution of the detector is equivalent to that of a cadmium zinc telluride gamma ray detector. The above results show that the beta- (Ga) -based alloy is based on 0.85 Al 0.15 ) 2 O 3 The radiation detector of the crystal shows excellent detection performance to X-ray and gamma ray.
Comparative example 1:
growth of beta- (Ga) by optical floating zone method 0.95 Al 0.05 ) 2 O 3 And (4) crystals.
Ga is weighed according to the molar ratio of 0.95 2 O 3 Powder and Al 2 O 3 Grinding the powder for 60 min to mix the powder uniformly, filling the mixed powder into a long rubber tube by using a funnel to prepare a raw material rod, pressing the raw material rod by using a cold isostatic press under the pressure of 50MPa, putting the raw material rod into a muffle furnace, and sintering the raw material rod in air at 1450 ℃ for 20 hours to prepare the powderForming a ceramic-like raw material rod. Growing crystal in an optical floating zone furnace in flowing air atmosphere, mounting the raw material rod on an upper rotating rod,<010>the seed crystal in the direction is fixed on the lower rotating rod, the voltage is slowly increased to heat the seed crystal and the raw material rod, the growth speed of the crystal is 3mm/h, the rotating speed is 14rpm, the air flow rate is 3L/min, the temperature is slowly reduced to the room temperature after the growth is finished, and the crystal is taken out. Cutting and polishing the crystal to obtain 5 × 5 × 1mm 3 The wafer of (1). As shown in FIG. 2, β - (Ga) 0.95 Al 0.05 ) 2 O 3 The crystal has obvious infrared absorption, which indicates that the crystal has higher free electron concentration. FIG. 9 shows β - (Ga) 0.95 Al 0.05 ) 2 O 3 The I-V curve of the crystal can reach larger current at low voltage, so the resistivity of the crystal is lower. Based on beta- (Ga) 0.95 Al 0.05 ) 2 O 3 The radiation detector made of the crystal has larger dark current.
Example 2:
growth of beta- (Ga) by optical floating zone method 0.9 Al 0.1 ) 2 O 3 And (4) crystals.
Ga is weighed according to the molar ratio of 0.9 2 O 3 Powder and Al 2 O 3 The powder was ground for 60 minutes to mix the powder uniformly, the uniformly mixed powder was charged into a long rubber tube using a funnel to prepare a raw material rod, the raw material rod was pressed using a cold isostatic press under a pressure of 50MPa, and the raw material rod was sintered in a muffle furnace at 1450 ℃ in air for 20 hours to prepare a ceramic-like raw material rod. Growing crystal in an optical floating zone furnace in flowing oxygen atmosphere, mounting the raw material rod on an upper rotating rod,<010>the seed crystal in the direction is fixed on the lower rotating rod, the voltage is slowly increased to heat the seed crystal and the raw material rod, the growth speed of the crystal is 4mm/h, the rotating speed is 14rpm, the flow rate of oxygen is 1L/min, the temperature is slowly reduced to the room temperature after the growth is finished, and the crystal is taken out. Cutting and polishing the crystal to obtain 5 × 5 × 1mm 3 The wafer of (1). As shown in FIG. 2, β - (Ga) 0.9 Al 0.1 ) 2 O 3 The crystal has no obvious infrared absorption, and the forbidden band width is 4.96eV. As shown in FIG. 5, the resistivity test gave β - (Ga) 0.9 Al 0.1 ) 2 O 3 The resistivity of the crystal was 3.8X 10 11 Omega cm. Preparation of a catalyst based on beta- (Ga) 0.9 Al 0.1 ) 2 O 3 The radiation detector of the crystal has a detection sensitivity of 283 mu CGy to X-rays at a voltage of 200V -1 cm -2 。
Example 3:
growth of beta- (Ga) by optical floating zone method 0.7 Al 0.3 ) 2 O 3 And (4) crystals.
Ga is weighed according to the molar ratio of 0.7 2 O 3 Powder and Al 2 O 3 The powder was ground for 60 minutes to mix the powder uniformly, the uniformly mixed powder was charged into a long rubber tube using a funnel to prepare a raw material rod, the raw material rod was pressed using a cold isostatic press under a pressure of 50MPa, and the raw material rod was sintered in a muffle furnace at 1450 ℃ in air for 20 hours to prepare a ceramic-like raw material rod. Growing crystals in an optical floating zone furnace in a flowing air atmosphere, mounting the raw material rod on an upper rotating rod,<010>the seed crystal in the direction is fixed on the lower rotating rod, the voltage is slowly increased to heat the seed crystal and the raw material rod, the growth speed of the crystal is 2mm/h, the rotating speed is 14rpm, the air flow rate is 5L/min, the temperature is slowly reduced to the room temperature after the growth is finished, and the crystal is taken out. Cutting and polishing the crystal to 5 × 5 × 1mm 3 The wafer of (2). Beta- (Ga) 0.7 Al 0.3 ) 2 O 3 The crystal is colorless and transparent and has no crack. As shown in FIG. 5, the resistivity test gave β - (Ga) 0.7 Al 0.3 ) 2 O 3 The resistivity of the crystal was 2.5X 10 12 Omega cm. Preparation of a catalyst based on beta- (Ga) 0.7 Al 0.3 ) 2 O 3 The radiation detector of the crystal has the detection sensitivity of 721 mu C Gy to X-rays at the voltage of 350V -1 cm -2 。
Comparative example 2:
growth of beta- (Ga) by optical floating zone method 0.68 Al 0.32 ) 2 O 3 And (4) crystals.
Ga is weighed according to the molar ratio of 0.68 2 O 3 Powder and Al 2 O 3 Grinding the powder for 60 minutes to mix the powder uniformly, and filling the uniformly mixed powder into a hopperThe long-strip-shaped rubber tube is made into a raw material rod, the raw material rod is pressed under the pressure of 50MPa by using a cold isostatic press, and the raw material rod is placed into a muffle furnace to be sintered for 20 hours at the temperature of 1450 ℃ in the air to be made into a ceramic raw material rod. Growing crystals in an optical floating zone furnace in a flowing air atmosphere, mounting the raw material rod on an upper rotating rod,<010>the directional seed crystal is fixed on the lower rotating rod, the voltage is slowly increased to heat the seed crystal and the raw material rod, the growth speed of the crystal is 2mm/h, the rotating speed is 14rpm, the air flow rate is 5L/min, the temperature is slowly reduced to the room temperature after the growth is finished, the crystal is taken out, and the crystal is turbid and opaque and has cracks, and the quality of the crystal is poor.
Example 4:
growth of beta- (Ga) by descent 0.88 Al 0.12 ) 2 O 3 And (4) crystals.
Ga is weighed according to the molar ratio of 0.88 2 O 3 Powder and Al 2 O 3 And grinding the powder for 60 minutes to uniformly mix the powder, pressing and molding the uniformly mixed powder by using a hydraulic press, and sintering the raw materials in a muffle furnace at 1450 ℃ in air for 20 hours to prepare the polycrystalline material. Putting the raw materials into a platinum-rhodium crucible for use<010>Directional seed crystal, vacuumizing to 5Pa, and charging CO 2 Heating to 1.03MPa until the raw materials are completely melted, keeping the temperature for 2 hours to ensure that the crucible slowly descends at the speed of 0.5mm/h, slowly cooling to room temperature after the growth is finished, and taking out the crystal. Cutting and polishing the crystal to 5 × 5 × 1mm 3 The wafer of (1). As shown in FIG. 5, the resistivity test gave β - (Ga) 0.88 Al 0.12 ) 2 O 3 The resistivity of the crystal was 9.1X 10 11 Omega cm. Preparation of a catalyst based on beta- (Ga) 0.88 Al 0.12 ) 2 O 3 The radiation detector of the crystal has the detection sensitivity of 379 mu C Gy to X-rays at the voltage of 200V -1 cm -2 。
Example 5:
czochralski method for growing beta- (Ga) 0.93 Al 0.07 ) 2 O 3 And (4) crystals.
Ga is weighed according to the molar ratio of 0.93 2 O 3 Powder and Al 2 O 3 Powder, grinding for 60 minutes to make powderUniformly mixing, pressing the uniformly mixed powder into a cake shape by using a hydraulic press, and sintering the raw materials in a muffle furnace at 1450 ℃ in air for 20 hours to prepare a polycrystalline material. Putting the raw materials into an iraurita crucible, and putting<010>The directional seed crystal is fixed in the seed crystal rod clamp. Vacuumizing to 5Pa according to the ratio of Ar to CO 2 Filling mixed gas into the reactor according to the proportion of =2 to 1.04MPa, heating the reactor until the raw material is completely melted, descending the seed crystal to be contacted with the melt, pulling the seed crystal after 20 minutes at the pulling speed of 3mm/h, slowly cooling the seed crystal to room temperature after necking, shouldering and isodiametric growth stages, and taking out the crystal. Cutting and polishing the crystal to 5 × 5 × 1mm 3 The wafer of (1). As shown in FIG. 5, the resistivity test gave β - (Ga) 0.93 Al 0.07 ) 2 O 3 The resistivity of the crystal was 8.5X 10 9 Omega cm. Preparation of a catalyst based on beta- (Ga) 0.93 Al 0.07 ) 2 O 3 The radiation detector of the crystal has the detection sensitivity of 174 mu C Gy to X-rays at the voltage of 200V -1 cm -2 。
Example 6:
growing beta- (Ga) by guided mode method 0.92 Al 0.08 ) 2 O 3 And (4) crystals.
Ga is weighed according to the molar ratio of 0.92 2 O 3 Powder and Al 2 O 3 Grinding the powder for 60 minutes to uniformly mix the powder, pressing the uniformly mixed powder into cakes by using a hydraulic press, and sintering the raw materials in a muffle furnace at 1450 ℃ in air for 20 hours to prepare a polycrystalline material. Putting the polycrystal material into an iraurita crucible, covering the crucible, and putting<010>The directional seed crystal is fixed in the seed crystal rod clamp. Vacuumizing to 7Pa, and charging CO 2 And (3) heating to 1.05MPa until the raw material is completely melted, descending the seed crystal to contact with the melt at the top of the die, pulling at a speed of 3mm/h after seeding and necking, performing isodiametric growth at a pulling speed of 5mm/h after the crystal is fully placed to the width of the die, slowly cooling to room temperature after the growth is finished, and taking out the crystal. Cutting and polishing the crystal to obtain 5 × 5 × 1mm 3 The wafer of (1). As shown in FIG. 5, the resistivity test resulted in β - (Ga) 0.92 Al 0.08 ) 2 O 3 The resistivity of the crystal was 3.2X 10 10 Ω·cm。Preparation of a catalyst based on beta- (Ga) 0.92 Al 0.08 ) 2 O 3 The radiation detector of the crystal has the detection sensitivity of 215 MuC Gy to X-rays at the voltage of 200V - 1 cm -2 。
The embodiments described above are described to facilitate an understanding and use of the invention by those skilled in the art. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the above embodiments, and those skilled in the art should make improvements and modifications within the scope of the present invention based on the disclosure of the present invention.

Claims (9)

1. The high-resistance gallium oxide crystal is characterized in that the molecular formula of the high-resistance gallium oxide crystal isβ-(Ga 1-x Al x ) 2 O 3 Wherein x is 0.07, 0.08, 0.12, 0.15, or 0.3.
2. The method for preparing high-resistance gallium oxide crystal according to claim 1, wherein the high-resistance gallium oxide crystal is prepared by a melt growth method comprising an optical float zone method, a Czochralski method, a guided mode method or a descent method.
3. The method for preparing high-resistance gallium oxide crystal according to claim 2, comprising the following steps:
(1) Taking Ga 2 O 3 Powder with Al 2 O 3 Powder, accurately weighing and uniformly mixing the raw material powder according to a molecular formula, performing compression molding in a hydraulic or isostatic pressing mode, and performing high-temperature solid-phase sintering to synthesize the aluminum-doped gallium oxide polycrystal material;
(2) Loading polycrystalline raw materials into an iridium crucible or a platinum-rhodium crucible or fixing the polycrystalline raw materials on an upper rotating rod of an optical float zone furnace;
(3) Fixing a directional seed crystal on a seed crystal rod;
(4) And growing the aluminum-doped gallium oxide crystal by adopting an optical floating zone method, a pulling method, a mode guiding method and a descending method.
4. The method for preparing a high-resistivity gallium oxide crystal according to claim 3, wherein the Ga in the step (1) 2 O 3 The purity of the powder is 4N-6N 2 O 3 The purity of the powder is 4N-5N.
5. The method for preparing the high-resistance gallium oxide crystal according to claim 3, wherein in step (2), when the Czochralski method, the mode-guiding method or the descent method is adopted, an iridium or platinum-rhodium crucible, carbon dioxide or a mixed atmosphere of carbon dioxide and argon is adopted; when the optical floating zone method is adopted for growth, an air atmosphere or a pure oxygen atmosphere is adopted, and the gas flow rate is 1-5L/min.
6. The use of a high-resistivity gallium oxide crystal according to claim 1, wherein the high-resistivity gallium oxide crystal is used for manufacturing a semiconductor radiation detector.
7. The use of a high-resistivity gallium oxide crystal according to claim 6, wherein the radiation detector uses a double-sided symmetrical electrode structure, and the double-sided symmetrical electrode is a Ti/Au double-layer metal electrode.
8. The use of a high-resistivity gallium oxide crystal according to claim 7, wherein the Ti layer has a thickness of 5-50nm, the Au layer has a thickness of 50-100nm, the electrode has a circular or rectangular shape, and the electrode has an area of 1-30mm 2 。
9. The use of the high-resistivity gallium oxide crystal according to claim 8, wherein the high-resistivity gallium oxide crystal is cut and double-sided chemically mechanical polished to a wafer thickness of 0.4-4mm.
CN202110825757.4A 2021-07-21 2021-07-21 High-resistance gallium oxide crystal and preparation method and application thereof Active CN113622027B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110825757.4A CN113622027B (en) 2021-07-21 2021-07-21 High-resistance gallium oxide crystal and preparation method and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110825757.4A CN113622027B (en) 2021-07-21 2021-07-21 High-resistance gallium oxide crystal and preparation method and application thereof

Publications (2)

Publication Number Publication Date
CN113622027A CN113622027A (en) 2021-11-09
CN113622027B true CN113622027B (en) 2022-12-16

Family

ID=78380640

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110825757.4A Active CN113622027B (en) 2021-07-21 2021-07-21 High-resistance gallium oxide crystal and preparation method and application thereof

Country Status (1)

Country Link
CN (1) CN113622027B (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114059173B (en) * 2022-01-17 2022-04-01 浙江大学杭州国际科创中心 Device and method for preparing gallium oxide material rod
CN115410922A (en) * 2022-09-07 2022-11-29 中国科学技术大学 Vertical gallium oxide transistor and preparation method thereof

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20170086473A (en) * 2014-11-25 2017-07-26 스미토모 긴조쿠 고잔 가부시키가이샤 Oxide sintered compact, sputtering target, and oxide semiconductor thin film obtained using same
CN105239162A (en) * 2015-08-25 2016-01-13 中国科学院上海光学精密机械研究所 Aluminum oxide-gallium oxide mixed-crystal material for wide-band-gap semiconductors
CN107068800B (en) * 2017-02-16 2018-12-18 大连理工大学 A kind of radiation detector and preparation method thereof based on gallium oxide single crystal
CN113035999B (en) * 2021-02-10 2024-06-25 杭州富加镓业科技有限公司 Al-doped gallium oxide X-ray detector and preparation method thereof

Also Published As

Publication number Publication date
CN113622027A (en) 2021-11-09

Similar Documents

Publication Publication Date Title
CN113622027B (en) High-resistance gallium oxide crystal and preparation method and application thereof
DE102005010790A1 (en) Photovoltaic cell with a photovoltaically active semiconductor material contained therein
US20230378388A1 (en) Methods for growing doped cesium lead halides
CN110325671A (en) Adulterate gallium oxide crystalline material and its preparation method and application
CN113035999B (en) Al-doped gallium oxide X-ray detector and preparation method thereof
CA2644536C (en) Compositions of doped, co-doped and tri-doped semiconductor materials
US11967659B2 (en) Semiconductor wafer, radiation detection element, radiation detector, and production method for compound semiconductor monocrystalline substrate
Kunikata et al. Annealing Temperature Dependence of Scintillation Properties of Ga-doped ZnO Translucent Ceramics.
EP1935031A2 (en) Photovoltaic cell comprising a photovoltaically active semi-conductor material contained therein
CN108342775B (en) Tantalum-doped beta gallium oxide crystalline material and preparation method and application thereof
CN111077560B (en) X-ray and gamma-ray detector based on magnesium-doped gallium oxide single crystal
CN112563118B (en) In-doped CdS film, preparation method and CIGS cell prepared by same
CN112125285B (en) Arsenic-doped or compound-doped cadmium selenide and preparation method thereof, thin-film solar cell and preparation method thereof
US20180196148A1 (en) Radiation detector
CN114315340B (en) High-nonlinearity ZnO-based polycrystalline ceramic and preparation method and application thereof
CN112993085A (en) Gallium oxide X-ray detector and preparation method thereof
Jani et al. Effect of annealing atmosphere on microstructure, optical and electronic properties of spray-pyrolysed In-doped Zn (O, S) thin films
JP2008184376A (en) Polycrystalline silicon, polycrystalline silicon substrate and its manufacturing method and photoelectric conversion element using polycrystal silicon substrate
CN113013292B (en) Improve and based on cesium lead bromine CsPbBr 3 Method of radiation detector performance of (a)
Schock et al. 2.16 Technology of large area Cu2S CdS solar cells
Roy et al. Unseeded growth of CdZnTe: In by THM technique
Ando et al. Properties of Highly c-axis Oriented Single-crystalline ZnO Layers Grown by Sputter Epitaxy for Hydrogen Gas and UV Sensors
Zdansky et al. Evaluation of semiinsulating annealed InP: Ta for radiation detectors
CN114551620A (en) Mixed-halogen all-inorganic perovskite single crystal X-ray detector
Kolesnikov et al. Crystal Growth and Characterization of Doped CZT Crystals

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant