US20070164434A1 - Semiconductor device having wiring made by damascene method and capacitor and its manufacture method - Google Patents
Semiconductor device having wiring made by damascene method and capacitor and its manufacture method Download PDFInfo
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- US20070164434A1 US20070164434A1 US11/507,438 US50743806A US2007164434A1 US 20070164434 A1 US20070164434 A1 US 20070164434A1 US 50743806 A US50743806 A US 50743806A US 2007164434 A1 US2007164434 A1 US 2007164434A1
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- insulating film
- interlayer insulating
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/52—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames
- H01L23/522—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames including external interconnections consisting of a multilayer structure of conductive and insulating layers inseparably formed on the semiconductor body
- H01L23/5222—Capacitive arrangements or effects of, or between wiring layers
- H01L23/5223—Capacitor integral with wiring layers
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L28/00—Passive two-terminal components without a potential-jump or surface barrier for integrated circuits; Details thereof; Multistep manufacturing processes therefor
- H01L28/40—Capacitors
- H01L28/60—Electrodes
- H01L28/75—Electrodes comprising two or more layers, e.g. comprising a barrier layer and a metal layer
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- 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
- H01L21/70—Manufacture or treatment of devices consisting of a plurality of solid state components formed in or on a common substrate or of parts thereof; Manufacture of integrated circuit devices or of parts thereof
- H01L21/71—Manufacture of specific parts of devices defined in group H01L21/70
- H01L21/768—Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics
- H01L21/76801—Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics characterised by the formation and the after-treatment of the dielectrics, e.g. smoothing
- H01L21/76802—Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics characterised by the formation and the after-treatment of the dielectrics, e.g. smoothing by forming openings in dielectrics
- H01L21/76807—Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics characterised by the formation and the after-treatment of the dielectrics, e.g. smoothing by forming openings in dielectrics for dual damascene structures
- H01L21/76808—Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics characterised by the formation and the after-treatment of the dielectrics, e.g. smoothing by forming openings in dielectrics for dual damascene structures involving intermediate temporary filling with material
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- 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
- H01L21/70—Manufacture or treatment of devices consisting of a plurality of solid state components formed in or on a common substrate or of parts thereof; Manufacture of integrated circuit devices or of parts thereof
- H01L21/71—Manufacture of specific parts of devices defined in group H01L21/70
- H01L21/768—Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics
- H01L21/76801—Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics characterised by the formation and the after-treatment of the dielectrics, e.g. smoothing
- H01L21/76829—Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics characterised by the formation and the after-treatment of the dielectrics, e.g. smoothing characterised by the formation of thin functional dielectric layers, e.g. dielectric etch-stop, barrier, capping or liner layers
- H01L21/76834—Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics characterised by the formation and the after-treatment of the dielectrics, e.g. smoothing characterised by the formation of thin functional dielectric layers, e.g. dielectric etch-stop, barrier, capping or liner layers formation of thin insulating films on the sidewalls or on top of conductors
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/52—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames
- H01L23/522—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames including external interconnections consisting of a multilayer structure of conductive and insulating layers inseparably formed on the semiconductor body
- H01L23/532—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames including external interconnections consisting of a multilayer structure of conductive and insulating layers inseparably formed on the semiconductor body characterised by the materials
- H01L23/53204—Conductive materials
- H01L23/53209—Conductive materials based on metals, e.g. alloys, metal silicides
- H01L23/53228—Conductive materials based on metals, e.g. alloys, metal silicides the principal metal being copper
- H01L23/53238—Additional layers associated with copper layers, e.g. adhesion, barrier, cladding layers
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/52—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames
- H01L23/522—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames including external interconnections consisting of a multilayer structure of conductive and insulating layers inseparably formed on the semiconductor body
- H01L23/532—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames including external interconnections consisting of a multilayer structure of conductive and insulating layers inseparably formed on the semiconductor body characterised by the materials
- H01L23/5329—Insulating materials
- H01L23/53295—Stacked insulating layers
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- 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
- the present invention relates to a semiconductor device and its manufacture method, and more particularly to a semiconductor device having wirings formed by a damascene method and capacitors and its manufacture method.
- a high frequency analog integrated circuit used in a mobile communication field or the like requires passive elements such as resistors, capacitors and inductors in addition to active elements (transistors and the like) operable at high speed, because of the characteristics of signals to be processed.
- passive elements such as resistors, capacitors and inductors
- active elements transistors and the like
- parasitic capacitance and resistance In order to improve an operation speed and reduce a consumption power, it is necessary to reduce parasitic capacitance and resistance.
- a capacitor of a metal-insulator-metal (MIM) structure is used more than a capacitor of a metal-oxide-semiconductor (MOS) structure.
- MIM metal-insulator-metal
- MOS metal-oxide-semiconductor
- FIG. 16 is a cross sectional view of a semiconductor device having wirings formed by a damascene method and capacitors of a MIM structure. In the following, a manufacture method for the semiconductor device shown in FIG. 16 will be described.
- An etching stopper film 101 of SiN and an interlayer insulating film 102 of SiO 2 are formed on an interlayer insulating film 100 .
- a wiring trench is formed through these two films and a copper wiring 103 is embedded in this wiring trench.
- an etching stopper film 106 of SiN is formed, the etching stopper film 106 serving as a film for preventing copper diffusion and for stopping progress of etching.
- a thin SiO 2 film 112 is formed on the etching stopper film 106 . This SiO 2 film 112 is not essential.
- a recess 110 is formed reaching the upper surface of the interlayer insulating film 100 .
- a TiN film as a lower electrode 115 A, an SiO 2 film as a capacitor dielectric film 116 A, a TiN film as an upper electrode 117 A and an SiN film as an upper insulating film 118 A are sequentially deposited on the whole surface of the substrate. These four layers are deposited also on the inner surface of the recess 110 . The four layers from the lower side TiN film to the SiN film are patterned in a shape of the lower electrode 115 A. In this case, the recess 110 is used as an alignment mark. Since the upper surface of the interlayer insulating film 102 is flat, the position of the lower level wiring 103 cannot be detected after the TiN film is formed on the interlayer insulating film 102 . The recess 110 is therefore formed to use it as the alignment mark.
- a capacitor 119 is constituted of the lower electrode 115 A of TiN, capacitor dielectric film 116 A of SiO 2 , and upper electrode 117 A of TiN.
- the TiN film 115 B, SiO 2 film 116 B, upper TiN film 117 B and SiN film 118 B are also left on the inner surface of the recess 110 .
- An interlayer insulating film 120 is formed covering the capacitor 119 , and the surface of the interlayer insulating film 120 is planarized. Via holes 122 A, 122 B and 122 C are formed through the interlayer insulating film 120 .
- the via hole 122 A passes beside the upper electrode 117 A and exposes the upper surface of the lower electrode 115 A.
- the via hole 122 B passes through the upper insulating film 118 A and exposes the upper surface of the upper electrode 117 A.
- the via hole 122 C passes through the SiO 2 film 112 and etching stopper film 106 and exposes the upper surface of the lower level wiring 103 .
- a conductor 151 is buried in a recess formed in a surface region of an interlayer insulating film 150 .
- Another interlayer insulating film 154 is formed on the interlayer insulating film 150 .
- a recess 155 is formed in the interlayer insulating film 154 .
- a partial upper surface of the lower level wiring 151 is exposed on the bottom surface of the recess 155 .
- a barrier metal film 160 of Ta or the like, a capacitor dielectric film 161 of SiO 2 or the like and a barrier metal film 162 of Ta or the like are sequentially deposited on the interlayer insulating film 154 and on the inner surface of the recess 155 .
- a conductive film 163 of Cu or the like is deposited on the barrier metal film 162 so that the recess 155 is completely filled with the conductive film 163 .
- CMP chemical mechanical polishing
- a wiring trench and via hole 156 is formed through the interlayer insulating film 154 .
- a partial upper surface of the lower level wiring 151 is exposed on the bottom of the via hole 156 .
- the whole surface including the inner surface of the wiring trench and via hole 156 is covered with a barrier metal film 170 , and a conductive film 171 is formed.
- the inside of the wiring trench and via hole 156 is filled with the conductive film 171 .
- CMP is performed until the upper surface of the interlayer insulating film 154 is exposed. A portion of the conductive film 171 is left in the wiring trench and via hole 156 . A capacitor is therefore formed, having the lower level wiring 151 as a lower electrode and the conductive film 163 contained in the recess 155 as an upper electrode.
- the wiring 151 as the lower electrode is connected to another constituent element of an electric circuit via the conductive film 171 contained in the wiring trench and via hole 156 .
- the photolithography process for forming the recess 155 shown in FIG. 17A is newly added as compared to the case in which the capacitor is not formed.
- FIG. 18A on an interlayer insulating film 200 , another interlayer insulating film 201 is formed.
- a wiring trench 206 and a capacitor groove 205 are formed in a surface layer of the interlayer insulating film 201 .
- the capacitor groove 205 is wider than the wiring trench 206 .
- a conductive film 210 is deposited under the condition that the inside of the wiring trench 206 is completely filled with the conductive film 210 and the inside of the capacitor groove 205 is partially filled with it.
- the surface of the conductive film 210 is covered with a capacitor dielectric film 211 .
- An upper conductive film 212 is deposited on the capacitor dielectric film 211 .
- the inside of the capacitor groove 205 is completely buried with the upper conductive film 212 .
- CMP is performed until the upper surface of the interlayer insulating film 201 is exposed.
- a lower electrode 210 A consisting of a portion of the conductive film 210 , a capacitor dielectric film 211 A, and an upper electrode 212 A consisting of a portion of the upper conductive film 212 are left in the capacitor groove 205 , to form a capacitor 215 .
- a wiring 210 B consisting of a portion of the conductive film 210 is left in the wiring trench 206 .
- the method of manufacturing the capacitor shown in FIGS. 18A and 18B do not require adding a new photolithography process.
- a distance between an outer border of the lower electrode 210 A and an outer edge of the capacitor dielectric film 211 A on the upper surface of the capacitor 215 depends on a thickness of the conductive film 210 shown in FIG. 18A .
- the width of the lower electrode 210 A has a sufficient margin relative to an alignment precision. If the conductive film 210 is made thick to make the width sufficiently wide, the capacitor groove 205 is completely filled with the conductive film 210 and a capacitor cannot be formed.
- An object of the present invention is to provide a semiconductor device having a capacitor structure having a high degree of freedom of a lead wiring structure and being able to be formed without adding a new photolithography process, and its manufacture method.
- a semiconductor device comprising:
- a capacitor embedded in the capacitor recess and including a lower electrode, a capacitor dielectric film and an upper electrode
- the lower electrode of the capacitor is made of a same material as a material of the first conductive member and disposed along a bottom surface and a side surface of the capacitor recess
- a concave portion is formed on an upper surface of the lower electrode
- the capacitor dielectric film covers an inner surface of the concave portion formed on the upper surface of the lower electrode
- the upper electrode is embedded in the concave portion.
- a method of manufacturing a semiconductor device comprising steps of:
- a capacitor can be manufactured without adding a new photolithography process. By adjusting a thickness of the lower conductive film, it becomes possible to adjust a width of the upper surface of the capacitor lower electrode made of a portion of the lower conductive film.
- FIGS. 1A to 1O are cross sectional views of a semiconductor device during manufacture according to a first embodiment.
- FIG. 1P is a cross sectional view of the semiconductor device according to the first embodiment.
- FIG. 2 is a plan view of the semiconductor device according to the first embodiment.
- FIG. 3 is a cross sectional view of the semiconductor device according to a second embodiment.
- FIG. 4 is a plan view of the semiconductor device according to the second embodiment.
- FIG. 5 is a cross sectional view of the semiconductor device according to a third embodiment.
- FIG. 6 is a plan view of the semiconductor device according to the third embodiment.
- FIG. 7 is a plan view of a semiconductor device according a modification of the third embodiment.
- FIG. 8 is a plan view of the semiconductor device according to the modification of the third embodiment.
- FIG. 9 is a cross sectional view of the semiconductor device according to a fourth embodiment.
- FIG. 10 is a plan view of the semiconductor device according to the fourth embodiment.
- FIGS. 11A and 11B are cross sectional views of a semiconductor device during manufacture according to a comparative example.
- FIGS. 12A and 12B are cross sectional views of a semiconductor device during manufacture according to a fifth embodiment.
- FIGS. 13A and 13B are cross sectional views of a semiconductor device during manufacture according to a sixth embodiment.
- FIGS. 14A and 14B are cross sectional views of a semiconductor device during manufacture according to a seventh embodiment.
- FIG. 15 is a cross sectional view of a semiconductor device during manufacture according to an eighth embodiment.
- FIG. 16 is a cross sectional view of a semiconductor device with a conventional capacitor.
- FIGS. 17A to 17D are cross sectional views of a semiconductor device with a conventional capacitor during manufacture.
- FIGS. 18A and 18B are cross sectional views of a semiconductor device with a conventional capacitor during manufacture.
- an isolation insulating film 2 of a shallow trench isolation (STI) structure is formed in a surface layer of a semiconductor substrate 1 made of silicon.
- a MOSFET 3 is formed in an active region defined by the isolation insulating film 2 .
- An etching stopper film 4 of SiN is formed on the surface of the semiconductor substrate 1 , covering MOSFET 3 .
- a first-layer interlayer insulating film 5 of phosphosilicate glass (PSG) or the like is formed on the etching stopper film 4 .
- Via holes 6 and 7 are formed through the first-layer interlayer insulating film 5 and etching stopper film 4 , and plugs 8 and 9 made of W or the like are embedded in the via holes 6 and 7 , respectively.
- the plugs 8 and 9 are connected to the source region and the drain region of the MOSFET 3 , respectively.
- the inner surfaces of the via holes 6 and 7 are covered with a barrier metal film of TiN or the like.
- a second-layer interlayer insulating film 13 is formed on the first-layer interlayer insulating film 5 .
- the second-layer interlayer insulating film 13 consists of three layers: an etching stopper film 10 of SiC or the like, an insulating film 11 of SiOC or the like and a cap film 12 of SiO 2 .
- a plurality of wiring trenches 15 are formed in the interlayer insulating film 13 .
- the inner surfaces of the wiring trenches 15 are covered with barrier metal films of Ta or the like, and the insides of the wiring trenches 15 are filled with conductive members made of copper.
- the conductive members 16 in the wiring trenches 15 constitute first-layer wirings.
- the wiring trenches 15 and conductive members 16 are formed by a single damascene method.
- a third-layer interlayer insulating film 23 is formed on the second-layer interlayer insulating film 13 .
- the third-layer interlayer insulating film 23 consists of three layers of an etching stopper film 20 of SiC or the like, an insulating film 21 of SIOC or the like and a cap film 22 of SiO 2 .
- a plurality of wiring trenches 25 and via holes 26 are formed in the interlayer insulating film 23 .
- the inner surfaces of the wiring trench 25 and via hole 26 are covered with a barrier metal film of Ta or the like, and the inside thereof is filled with a conductive member 28 of copper.
- the conductive member 28 in the wiring trench 25 constitutes a wiring
- the conductive member 28 in the via hole 26 constitutes an interconnect portion between the upper and lower wirings.
- the wiring trench 25 , via hole 26 and conductive member 28 are formed by a dual damascene method.
- a plurality of wiring layers are formed having a structure similar to that of the third-layer wiring structure.
- the interlayer insulating film 44 has a lamination structure of an etching stopper film 40 of SiN having a thickness of 50 nm, a via layer insulating film 41 of SiO 2 having a thickness of 350 nm, an etching stopper film 42 of SiN having a thickness of 50 nm and a Wiring layer insulating film 43 of SiO 2 having a thickness of 350 nm stacked in this order. These films are deposited by, e.g., chemical vapor deposition (CVD).
- CVD chemical vapor deposition
- FIG. 1B a wiring trench and a via hole are formed in the interlayer insulating film 44 by a damascene method, and a conductive member of copper or copper alloy is embedded in the wiring trench and via hole.
- FIGS. 1B to 1N show only the lamination structure above the wiring layer 30 .
- a conductive member 45 is embedded in a recess formed in the wiring layer insulating film 43 and etching stopper film 42 in the region where a capacitor is to be formed.
- wirings 46 and 47 are disposed.
- the wiring 47 is connected to a lower level wiring via a via hole passing through the via layer insulating film 41 and etching stopper film 40 .
- the inner surfaces of the wiring trench and via hole are covered with a barrier metal film of Ta or the like having a thickness of 30 nm.
- an interlayer insulating film 54 of a four-layer structure is formed on the interlayer insulating film 44 .
- the interlayer insulating film 54 consists of an etching stopper film 50 of SiN having a thickness of 50 nm, a via layer insulating film 51 of SiO 2 having a thickness of 750 nm, an etching stopper film 52 of SiN having a thickness of 50 nm and a wiring layer insulating film 53 of SiO 2 having a thickness of 350 nm stacked in this order. These films are deposited by, e.g., plasma enhanced CVD.
- the via layer insulating film 51 may be formed thicker than a targeted thickness, and thereafter the surface thereof is planarized by CMP to form the via layer insulating film 51 having a targeted thickness.
- a resist film 57 is formed on the interlayer insulating film 54 .
- This resist film 57 is exposed and developed to form openings 57 A and 57 B.
- the opening 57 A is disposed at the position corresponding to the conductive member 45 formed in the lower level interlayer insulating film 44 , i.e., at the position where a capacitor is to be formed, and the plan shape and size thereof are a rectangle having a shorter side length of about 5 ⁇ m.
- the other opening 57 B corresponds to a via hole to be formed in the via layer insulating film 51 , and the plan shape and size thereof are a square having a side length of about 0.5 ⁇ m.
- etching is performed down to the upper surface of the etching stopper film 50 by plasma etching using CF-based gas.
- the wiring layer insulating film 53 , etching stopper film 52 and via layer insulating film 51 are etched under the conditions suitable for these film materials.
- the resist mask 57 is removed by plasma ashing using O 2 gas.
- a recess 51 A is therefore formed in the region where a capacitor is to be formed, and a via hole 51 B is formed in another region.
- resin is coated on the substrate and partially melted by wet etching, plasma etching or the like to leave protective members 56 A and 56 B in partial spaces of the recess 51 A and via hole 51 B.
- a resist film 58 is formed on the interlayer insulating film 54 , and openings 58 A, 58 B and 58 C are formed.
- the opening 58 A has a shape and size including the recess 51 A where a capacitor is to be disposed as viewed in plan.
- the openings 58 B and 58 C correspond to a wiring to be formed in the wiring layer insulating film 53 .
- the opening 58 B partially overlaps with the via hole 51 B as viewed in plan.
- the wiring layer insulating film 53 is etched by plasma etching using CF-based gas until the etching stopper film 52 is exposed.
- the protective members 56 A and 56 B protect the etching stopper film 50 on the bottoms of the recess 51 A and via hole 51 B.
- a recess 53 A, and wiring trenches 53 B and 53 C are therefore formed through the wiring layer insulating film 53 .
- the resist film 58 and protective members 56 A and 56 B are removed by plasma ashing using O 2 gas.
- the etching stopper films 52 and 50 left on the bottoms of the recesses 53 A and 51 A, on the bottoms of the wiring trenches 53 B and 53 C and on the bottom of the via hole 51 B are removed.
- the etching stopper films 52 and 50 can be removed by plasma etching using CF-based gas, CHF-based gas or mixture gas thereof.
- a capacitor recess 55 is therefore formed having a two-step structure constituted of the recesses 51 A and 53 A.
- the recesses 51 A and 53 A are called a “via layer portion” and a “wiring layer portion” of the capacitor recess 55 .
- a barrier metal film 60 of Ta having a thickness of 30 nm is formed on the whole substrate surface by sputtering.
- the barrier metal film 60 may be made of TaN, TiN or the like.
- a seed film of copper having a thickness of 100 nm is formed on the barrier metal film 60 by sputtering. By using this seed film as an electrode, copper is electroplated to deposit a lower conductive film 62 .
- a thickness of the lower conductive film 62 is set in such a manner that the insides of the wiring trench 53 B, via hole 51 B and wiring trench 53 C are completely filled with the lower conductive film.
- the capacitor recess 55 Since the capacitor recess 55 has a plan shape wider than that of the wiring trench and via hole, the inside thereof cannot be completely buried. A partial upper surface of the lower conductive film 62 deposited in the via layer portion 51 A of the capacitor recess 55 becomes lower than the upper surface of the wiring layer insulating film 53 . This is because the capacitor recess 55 is deeper than the wiring trenches 53 B and 53 C. Although a depth to the bottom of the via hole 51 B is equal to a depth of the capacitor recess 55 , the size of the plan shape of the via hole 51 B is smaller than the thickness of the via layer insulating film 51 , so that the via hole 51 B is completely filled through isotropic growth. A region outside of the via layer portion 51 A of the capacitor recess 55 and inside of the wiring layer portion 53 A as viewed in plan is completely filled with the lower conductive film 62 .
- a dielectric film 65 of SiN having a thickness of 50 nm is formed on the lower conductive film 62 by plasma enhanced CVD.
- the dielectric film 65 may be made of insulating material different from SiN, such as SiC, SiCN or the like.
- the dielectric film may have a two-layer structure of an oxide insulating layer of Ta, Hf, Al or the like and an insulating layer of SiN, SiC, SICN or the like.
- a barrier metal film 66 of Ta having a thickness of 30 nm is formed on the dielectric film 65 by sputtering.
- a copper seed film is formed on the barrier metal film 66 and copper is electroplated to form an upper conductive film 68 having a thickness of 900 nm.
- the space in the capacitor recess 55 still not filled is completely filled with the upper conductive film 68 .
- the lower conductive film 62 and upper conductive film 68 may be made of metal different from copper, such as aluminum (Al), silver (Ag) or the like.
- CMP is performed until the upper surface of the wiring layer insulating film 53 is exposed.
- This CMP method will be described in the following. First, CMP is performed until the barrier metal 66 shown in FIG. 1K is exposed, under the condition that the upper electrode film 68 can be easily and selectively polished relative to the barrier metal film 66 . Next, by changing the polishing conditions, the barrier metal film 66 and dielectric film 65 are polished. Next, CMP is performed until the barrier metal 60 is exposed, under the condition that the lower conductive film 62 can be easily and selectively polished relative to the barrier metal film 60 . Lastly, the barrier metal film 60 is polished to expose the wiring layer insulating film 53 . Under the condition that the five layers from the barrier metal film 60 to upper conductive film 68 can be polished generally at an equal rate, CMP may be performed until the wiring layer insulating film 53 is exposed, without changing the polishing conditions.
- a capacitor 69 is therefore formed being constituted of a lower electrode 62 A consisting of a portion of the lower conductive film 62 left in the capacitor recess 55 , a capacitor dielectric film 65 A consisting of a portion of the dielectric film 65 and an upper electrode 68 A consisting of a portion of the upper conductive film 68 .
- a wiring 62 B consists of a portion of the lower conductive film 62 left in the wiring trench 53 B and via hole 51 B
- a wiring 62 C consists of a portion of the lower conductive film 62 left in the wiring trench 53 C.
- the upper electrode 68 A of the capacitor 69 is located within the via layer portion 51 A of the capacitor recess 55 .
- the barrier metal film 60 A and lower electrode 62 A embedded in the wiring layer portion 53 A in a region outside the via layer portion 51 A has the same lamination structure as the barrier metal film 60 C and wiring 62 C in the other wiring trench 53 C formed in the wiring layer insulating film 53 .
- an interlayer insulating film 72 is formed on the interlayer insulating film 54 .
- the interlayer insulating film 72 has a two-layer structure of an etching stopper film 70 of SiN having a thickness of 70 nm and a via layer insulating film 71 of SiO 2 having a thickness of 900 nm stacked in this order.
- the surface of the via layer insulating film 71 is planarized by CMP.
- via holes 71 D, 71 A and 71 B are formed through the interlayer insulating film 72 .
- the upper electrode 68 A of the capacitor 69 is therefore exposed on the bottom of the via hole 71 D
- the lower electrode 62 A is exposed on the bottom of the via hole 71 A.
- the wiring 62 B is exposed on the bottom of the via hole 71 B.
- the via hole 71 A is disposed at a position outside the via layer portion 51 A of the capacitor recess 55 and partially superposing upon the wiring layer portion 53 A.
- a barrier metal film is formed covering the inner surfaces of the via holes 71 D, 71 A and 71 B, and plugs 73 D, 73 A and 73 B of tungsten (W) are embedded in the via holes 71 D, 71 A and 71 B.
- the barrier metal film is made of TiN, WN, WSiN or the like. Wirings 75 D, 75 A and 75 B are formed on the interlayer insulating film 72 .
- Each of these wirings consists of a lower barrier metal film having a lamination structure of a Ti film and a TiN film and a thickness of 50 nm, a main portion made of aluminum (Al) or copper-added aluminum (AlCu) having a thickness of 900 nm and an upper barrier metal film having a lamination structure of a Ti film and a TiN film and a thickness of 50 nm.
- the wirings 75 D, 75 A and 75 B are connected to the plugs 73 D, 73 A and 73 B, respectively. Pads (not shown) are formed in other regions of the same layer as that of these wirings.
- an interlayer insulating film 80 of SiO 2 having a thickness of 900 nm is formed on the whole substrate surface, and a cover film 81 of SiN having a thickness of 500 nm is formed on the interlayer insulating film 80 . Openings (not shown) are formed through the interlayer insulating film 80 and cover film 81 to expose the pads.
- FIG. 2 is a plan view of the capacitor in the semiconductor device according to the first embodiment.
- a cross sectional view taken along one-dot chain line A 1 -A 1 shown in FIG. 2 corresponds to the cross sectional views shown in FIGS. 1A to 1P .
- the conductive member 45 is disposed in the interlayer insulating film below the capacitor 69 .
- the via layer portion 51 A of the capacitor recess 55 is located within the conductor member 45
- the upper electrode 68 A is located within the via layer portion 51 A. Since the plan shape of the upper electrode 68 A is not defined by photolithography, an exposure mask is not used for the upper electrode 68 A.
- the wiring layer portion 53 A includes the via layer portion 51 A therein.
- a plurality of via holes 71 D for connection to the wiring 75 D are disposed within the upper electrode 68 A.
- a plurality of via holes 71 A for connection to the wiring 75 A are disposed inside the wiring layer portion 53 A of the capacitor recess 55 and outside the via layer portion 51 A.
- the via layer portion 51 A of the capacitor recess 55 is formed at the same time when the via hole 51 B is formed in the process shown in FIG. 1D .
- the wiring layer portion 53 A is formed at the same time when the wiring trenches 53 B and 53 C are formed in the process shown in FIG. 1G . Therefore, it is not necessary to prepare a mask pattern for exclusive use for forming the capacitor.
- the size of the region between an outer periphery of the via layer portion 51 A of the capacitor recess 55 shown in FIG. 2 and an outer periphery of the wiring portion 53 A can be set as desired by mask pattern designs. In this region, the upper flat surface of the lower electrode 62 A of the capacitor 69 is disposed. It is therefore possible to easily align the position of the via holes 71 A for connection between the lower electrode 62 A and upper wiring 75 A.
- FIG. 3 is a cross sectional view of a semiconductor device of the second embodiment. Description will be made by paying attention to different points from the semiconductor device of the first embodiment shown in FIG. 1P .
- the conductive member 45 is not disposed below the capacitor 55 shown in FIG. 1P . Further, the plug 73 A and wiring 75 A connected to the upper surface of the lower electrode 62 A of a capacitor 69 are not disposed. If the lower electrode 62 A of the capacitor 69 has sufficiently low resistance, the supplementary conductive member 45 is not required to be disposed.
- FIG. 4 is a plan view of the semiconductor device of the second embodiment.
- a cross sectional view taken along one-dot chain line A 3 -A 3 in FIG. 4 corresponds to FIG. 3 .
- a wiring 62 L is disposed in place of the wiring 75 A of the semiconductor device of the first embodiment shown in FIG. 2 .
- the wiring 62 L is embedded in a wiring trench 53 L formed in the wiring layer insulating film 53 in which the wiring portion 53 A of the capacitor recess 55 is formed.
- the electrode lead wiring 62 L can be disposed in this manner in the same layer as that of the lower electrode 62 A.
- FIG. 5 is a cross sectional view of a semiconductor device of the third embodiment. Description will be made by paying attention to different points from the semiconductor device of the first embodiment shown in FIG. 1P .
- the side surfaces of the wiring portion 53 A and via layer portion 51 A of the capacitor recess 55 are flush with each other in the cross sectional view shown in FIG. 5 .
- the plug 73 A and upper level wiring 75 A connected to the lower electrode 62 A on the upper surface thereof are not disposed.
- FIG. 6 is a plan view of the semiconductor device of the third embodiment.
- a cross sectional view taken along one-dot chain line A 5 -A 5 in FIG. 6 corresponds to FIG. 5 .
- the outer peripheries of the via layer portion 51 A and wiring portion 53 A of the capacitor recess 55 coincide with each other.
- a wiring 45 L is disposed in place of the wiring 75 A connected to the lower electrode 62 A.
- the wiring 45 L is embedded in a wiring trench formed in the interlayer insulating film 44 in which the conductive member 45 is disposed, and is continuous with the conductive member 45 .
- the electrode lead wiring 45 L can be disposed in the interlayer insulating film 44 under the capacitor 69 .
- a mask pattern in which an opening 58 A of the resist film 58 for forming the wiring layer portion 53 A of the capacitor recess 55 is located within the via layer portion 51 A, may be used.
- the protective member 56 A is exposed on the whole bottom of the opening 58 A.
- the wiring layer insulating film 53 where the capacitor is to be disposed is not etched. Therefore, the capacitor recess 55 has a side surface without a step.
- the opening 58 A for forming the wiring layer portion 53 A shown in FIG. 7 may not be formed. Also in this case, the capacitor recess 55 is formed having the same structure as that shown in FIG. 7 .
- FIG. 9 is a cross sectional view of a semiconductor device of the fourth embodiment. Description will be made by paying attention to different points from the semiconductor device of the third embodiment shown in FIGS. 5 and 6 . Also in the fourth embodiment, as in the case of the third embodiment, a step is not formed on the side surface of the capacitor recess 55 as shown in the cross sectional view shown in FIG. 9 . In the fourth embodiment, the conductive member 45 disposed below the capacitor 69 shown in FIG. 5 is not formed. Instead, the lower electrode 62 A of the capacitor 69 is connected to an upper level wiring 75 A via a plug 73 B in a via hole 71 A formed in the upper interlayer insulating film 72 .
- FIG. 10 is a plan view of the semiconductor device of the fourth embodiment.
- a cross sectional view taken along one-dot chain line A 9 -A 9 in FIG. 10 corresponds to FIG. 9 .
- the via hole 71 A does not overlap with the upper electrode 68 A, but is disposed so as to overlap with the via layer portion 51 A of the capacitor recess 55 . If a width from the outer periphery of the via layer portion 51 A to the border of the upper electrode 68 A is about 700 nm, position alignment of the via hole 71 A can be performed at a sufficient precision. In order to satisfy this condition, it is sufficient if the thickness of the lower conductive film 62 shown in FIG. 1J is about 700 nm.
- the thickness of the interlayer insulating film 54 (a depth of the capacitor recess 55 ) is 1200 nm, even if the thickness of the lower conductive film 62 is set to about 700 nm, a partial upper surface of the lower conductive film 62 is lower than the upper surface of the interlayer insulating film 54 .
- the surface of the lower conductive film 62 formed by electroplating copper directly reflects the underlying stepwise shape, and the sidewalls of the concave portions formed on the surface of the lower conductive film 62 cross the flat surface generally at a right angle. Depending upon electroplating conditions, a cross portion between the side surface and flat surface is rounded. Reflecting this round portion, the surfaces of the dielectric film 65 and barrier metal film 66 are also rounded.
- the inner surface itself of the capacitor recess 55 has a rounded portion where the side surface and flat surface are crossing with each other. In this case, reflecting this underlying rounded surface, the surface of the lower conductive film 62 is rounded.
- FIG. 11A is a cross sectional view showing a structure in which the surface is rounded, where the flat surface and the side surface of the recess formed on the surface of the lower conductive film 62 are crossing with each other.
- An upper surface 92 of the lower conductive film 62 is generally flush with the upper surface of the wiring layer insulating film 53 , above the portion where a bottom 90 of the wiring portion 53 A of the capacitor recess 55 and a side surface 91 of the via layer portion 51 A are crossing with each other.
- FIG. 11B As shown in FIG. 11B , as CMP is performed down to the upper surface of the wiring layer insulating film 53 , rounded portions of the dielectric film 65 and barrier metal film 66 are left in the capacitor recess 55 . Therefore, in the cross sectional view shown in FIG. 11B , a corner having an acute angle occurs at a cross portion 93 between an outer surface of the barrier metal film 66 A and the upper flat surface of the capacitor 69 . An electric field concentrates upon this corner, so that the breakdown voltage characteristics are degraded.
- FIG. 12A is a cross sectional view of a semiconductor device during manufacture according to the fifth embodiment.
- the lower conductive film 62 is formed in such a manner that an upper surface 92 of the lower conductive film 62 is higher than an upper surface of the wiring insulating film 53 by a predetermined value, above a portion where the side surface 91 of the via layer portion 51 A and the bottom surface 90 of the wiring layer portion 53 A of the capacitor recess 55 are crossing with each other.
- a rounded portion where the upper surface 92 and the side surface of a concave portion on the surface of the lower conductive film 62 formed in the via layer portion 51 A of the capacitor recess 55 , positions above the upper surface of the wiring layer insulating film 53 . Therefore, the rounded portion can be removed by CMP.
- FIG. 12B shows the structure after CMP.
- the outer surface of the barrier metal film 66 A left in the capacitor recess 55 and the upper flat surface of the capacitor 69 are crossing with each other generally at a right angle. Since the corner having an acute angle shown in FIG. 11B is not formed, it is possible to suppress electric field concentration and avoid degradation of the breakdown voltage characteristics.
- the lower conductive film 62 is formed in such a manner that the upper surface 92 of the lower conductive film 62 is higher than the upper surface of the wiring layer insulating film 53 by 350 nm or more, in the structure shown in FIG. 12A .
- coverage may be lowered in some cases.
- An occurrence frequency of coverage defects can be lowered by forming a rounded portion where the flat surface and the side surface are crossing with other. For example, if an intersection between the bottom surface and the side surface of the capacitor recess 55 is angulated and the barrier metal film 60 is formed by sputtering, coverage at the right angle corner is generally degraded. By rounding the intersection, coverage of a film to be formed on this intersection can be suppressed from being lowered.
- FIG. 13A is a partially enlarged diagram showing the state after CMP of the first embodiment shown in FIG. 1L .
- CMP is performed under the condition that a polishing rate of the barrier metal film 60 A and 66 A is faster than a polishing rate of the wiring layer insulating film 53 , capacitor dielectric film 65 A, lower electrode 62 A and upper electrode 68 A.
- the upper end of the border of the barrier metal film 66 A is lower than the upper end of the border of the capacitor dielectric film 65 A and the upper surface of the upper electrode 68 A.
- Concave portions 95 and 96 are therefore formed at positions corresponding to the borders of the barrier metal films 60 A and 66 A.
- the concave portions 95 and 96 are filled with the etching stopper film 70 .
- the upper end of the border of the barrier metal film 66 A is spaced from the border of the upper surface of the lower electrode 62 A only by a thickness of the capacitor dielectric film 65 A.
- a distance between the upper end of the border of the barrier metal film 66 A and the border of the upper surface of the lower electrode 62 A corresponds to sum of a thickness of the capacitor dielectric film 65 A and a depth of the concave portion 96 .
- An interface between the capacitor dielectric film 65 A and etching stopper film 70 is likely to cause an increase in leak current and breakdown voltage degradation.
- a path on the interface from one electrode to the other electrode of the capacitor 69 is elongated, so that it is possible to prevent an increase in leak current and breakdown voltage degradation.
- a polishing rate of the lower electrode 62 A and upper electrode 68 A is faster than a polishing rate of the wiring layer insulating film 53 , barrier metal film 60 A and 66 A and capacitor dielectric film 65 A.
- FIG. 14A shows the structure after CMP.
- the upper ends of the capacitor dielectric film 65 A and barrier metal film 66 A protrude from the upper surface of the lower electrode 62 A and the upper surface of the upper electrode 68 A.
- FIG. 14B shows the structure after the barrier metal film 70 is formed.
- a distance between the upper end of the border of the barrier metal film 66 A and the border of the upper surface of the lower electrode 62 A corresponds to sum of a thickness of the capacitor dielectric film 65 A and a height from the upper surface of the lower electrode 62 A to the upper end of the capacitor dielectric film 65 A.
- FIG. 15 is a cross sectional view showing a capacitor portion of a semiconductor device of the eighth embodiment. Description will be made by paying attention to different points from the semiconductor device of the fifth embodiment shown in FIGS. 12A and 12B . Description is omitted for the same constituent elements as those of the semiconductor device of the fifth embodiment.
- the surface of the lower conductive film 62 has rounded portions at the intersection between the region in conformity with the bottom surface and the region in conformity with the side surface of the capacitor recess 55 .
- a sloped surface is formed on the surface of the lower conductive film 62 at the intersection between the region in conformity with the bottom surface and the side surface of the capacitor recess 55 .
- the sloped surface is formed particularly when the lower conductive film 62 is deposited under the conditions that a narrow via hole is filled with the lower conductive film 62 at good reproductivity.
- the lower conductive film 62 is formed in such a manner that the upper surface 92 of the lower conductive film 62 is higher than the upper surface of the wiring layer insulating film 53 by 350 to 400 nm or more.
- the via layer insulating film and wiring layer insulating film constituting the interlayer insulating film are made of SiO 2
- other insulating material may also be used, such as inorganic insulating materials SiOF, SiN, SiC, SiCN, SiON and the like or low dielectric constant organic insulating materials.
- Porous insulating materials may also be used. It is preferable to combine these materials and the material of the etching stopper film so as to ensure a sufficient etching selectivity.
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Abstract
Description
- This application is based on and claims priority of Japanese Patent Application No. 2006-007658 filed on Jan. 16, 2006, the entire contents of which are incorporated herein by reference.
- A) Field of the Invention
- The present invention relates to a semiconductor device and its manufacture method, and more particularly to a semiconductor device having wirings formed by a damascene method and capacitors and its manufacture method.
- B) Description of the Related Art
- Generally, a high frequency analog integrated circuit used in a mobile communication field or the like requires passive elements such as resistors, capacitors and inductors in addition to active elements (transistors and the like) operable at high speed, because of the characteristics of signals to be processed. In order to improve an operation speed and reduce a consumption power, it is necessary to reduce parasitic capacitance and resistance. In order to reduce parasitic capacitance and resistance, a capacitor of a metal-insulator-metal (MIM) structure is used more than a capacitor of a metal-oxide-semiconductor (MOS) structure.
-
FIG. 16 is a cross sectional view of a semiconductor device having wirings formed by a damascene method and capacitors of a MIM structure. In the following, a manufacture method for the semiconductor device shown inFIG. 16 will be described. - An
etching stopper film 101 of SiN and aninterlayer insulating film 102 of SiO2 are formed on aninterlayer insulating film 100. A wiring trench is formed through these two films and acopper wiring 103 is embedded in this wiring trench. On theinterlayer insulating film 102, anetching stopper film 106 of SiN is formed, theetching stopper film 106 serving as a film for preventing copper diffusion and for stopping progress of etching. A thin SiO2 film 112 is formed on theetching stopper film 106. This SiO2film 112 is not essential. Arecess 110 is formed reaching the upper surface of theinterlayer insulating film 100. - A TiN film as a
lower electrode 115A, an SiO2 film as a capacitordielectric film 116A, a TiN film as anupper electrode 117A and an SiN film as an upperinsulating film 118A are sequentially deposited on the whole surface of the substrate. These four layers are deposited also on the inner surface of therecess 110. The four layers from the lower side TiN film to the SiN film are patterned in a shape of thelower electrode 115A. In this case, therecess 110 is used as an alignment mark. Since the upper surface of the interlayerinsulating film 102 is flat, the position of thelower level wiring 103 cannot be detected after the TiN film is formed on theinterlayer insulating film 102. Therecess 110 is therefore formed to use it as the alignment mark. - Next, the SiO2 film, upper level TiN film and SiN film are patterned in a shape of the
upper electrode 117A. Acapacitor 119 is constituted of thelower electrode 115A of TiN, capacitordielectric film 116A of SiO2, andupper electrode 117A of TiN. The TiNfilm 115B, SiO2film 116B, upper TiNfilm 117B and SiNfilm 118B are also left on the inner surface of therecess 110. - An interlayer
insulating film 120 is formed covering thecapacitor 119, and the surface of theinterlayer insulating film 120 is planarized. Viaholes insulating film 120. Thevia hole 122A passes beside theupper electrode 117A and exposes the upper surface of thelower electrode 115A. Thevia hole 122B passes through the upperinsulating film 118A and exposes the upper surface of theupper electrode 117A. Thevia hole 122C passes through the SiO2film 112 and etchingstopper film 106 and exposes the upper surface of thelower level wiring 103. - After the inner surfaces of these via
holes Wirings interlayer insulating film 120. Thewirings - With the above-described manufacture method, it is necessary to conduct photolithography once at each of the process of forming the
recess 110, the process of patterning thelower electrode 115A and the process of patterning theupper electrode 117A. Namely, three photolithography processes are newly added as compared to the case in which thecapacitor 119 is not formed. - With reference to
FIGS. 17A to 17E , description will be made on a capacitor manufacture method disclosed in JP-A-2005-51247. - As shown in
FIG. 17A , aconductor 151 is buried in a recess formed in a surface region of aninterlayer insulating film 150. Anotherinterlayer insulating film 154 is formed on theinterlayer insulating film 150. Arecess 155 is formed in theinterlayer insulating film 154. A partial upper surface of thelower level wiring 151 is exposed on the bottom surface of therecess 155. Abarrier metal film 160 of Ta or the like, acapacitor dielectric film 161 of SiO2 or the like and abarrier metal film 162 of Ta or the like are sequentially deposited on theinterlayer insulating film 154 and on the inner surface of therecess 155. Aconductive film 163 of Cu or the like is deposited on thebarrier metal film 162 so that therecess 155 is completely filled with theconductive film 163. - As shown in
FIG. 17B , chemical mechanical polishing (CMP) is preformed to expose the upper surface of theinterlayer insulating film 154. Thebarrier metal film 160,capacitor dielectric film 161,barrier metal film 162 andconductive film 163 are left in therecess 155. - As shown in
FIG. 17C , a wiring trench and viahole 156 is formed through theinterlayer insulating film 154. A partial upper surface of thelower level wiring 151 is exposed on the bottom of the viahole 156. - As shown in
FIG. 17D , the whole surface including the inner surface of the wiring trench and viahole 156 is covered with abarrier metal film 170, and aconductive film 171 is formed. The inside of the wiring trench and viahole 156 is filled with theconductive film 171. - As shown in
FIG. 17E , CMP is performed until the upper surface of theinterlayer insulating film 154 is exposed. A portion of theconductive film 171 is left in the wiring trench and viahole 156. A capacitor is therefore formed, having thelower level wiring 151 as a lower electrode and theconductive film 163 contained in therecess 155 as an upper electrode. Thewiring 151 as the lower electrode is connected to another constituent element of an electric circuit via theconductive film 171 contained in the wiring trench and viahole 156. - With the method shown in
FIGS. 17A to 17E , the photolithography process for forming therecess 155 shown inFIG. 17A is newly added as compared to the case in which the capacitor is not formed. - With reference to
FIGS. 18A and 18B , description will be made on a capacitor manufacture method disclosed in JP-A-2003-86695. - As shown in
FIG. 18A , on aninterlayer insulating film 200, anotherinterlayer insulating film 201 is formed. Awiring trench 206 and acapacitor groove 205 are formed in a surface layer of theinterlayer insulating film 201. Thecapacitor groove 205 is wider than thewiring trench 206. Aconductive film 210 is deposited under the condition that the inside of thewiring trench 206 is completely filled with theconductive film 210 and the inside of thecapacitor groove 205 is partially filled with it. The surface of theconductive film 210 is covered with acapacitor dielectric film 211. An upperconductive film 212 is deposited on thecapacitor dielectric film 211. The inside of thecapacitor groove 205 is completely buried with the upperconductive film 212. - As shown in
FIG. 18B , CMP is performed until the upper surface of theinterlayer insulating film 201 is exposed. Alower electrode 210A consisting of a portion of theconductive film 210, acapacitor dielectric film 211A, and anupper electrode 212A consisting of a portion of the upperconductive film 212 are left in thecapacitor groove 205, to form acapacitor 215. Awiring 210B consisting of a portion of theconductive film 210 is left in thewiring trench 206. - With the method shown in
FIGS. 18A and 18B , it is not necessary to add a new photolithography process to form thecapacitor 215. - In order to form the capacitor shown in
FIG. 16 , it is necessary to newly add three photolithography processes. In order to form the capacitor shown inFIGS. 17A to 17E , it is necessary to newly add one photolithography process. - The method of manufacturing the capacitor shown in
FIGS. 18A and 18B do not require adding a new photolithography process. However, a distance between an outer border of thelower electrode 210A and an outer edge of thecapacitor dielectric film 211A on the upper surface of thecapacitor 215 depends on a thickness of theconductive film 210 shown inFIG. 18A . In order to contact a conductive plug to the exposed upper surface of thelower electrode 210A, it is necessary that the width of thelower electrode 210A has a sufficient margin relative to an alignment precision. If theconductive film 210 is made thick to make the width sufficiently wide, thecapacitor groove 205 is completely filled with theconductive film 210 and a capacitor cannot be formed. It is therefore difficult to connect a lead wiring to the upper surface of thelower electrode 210A of thecapacitor 215 having the structure shown inFIG. 18B . In order to connect a lead wiring to thelower electrode 210A with good reproductivity, the lead wiring is probably required to be in contact with the bottom of thelower electrode 210A. - An object of the present invention is to provide a semiconductor device having a capacitor structure having a high degree of freedom of a lead wiring structure and being able to be formed without adding a new photolithography process, and its manufacture method.
- According to one aspect of the present invention, there is provided a semiconductor device comprising:
- a first interlayer insulating film formed over a principal surface of a semiconductor substrate;
- a first wiring trench formed in the first interlayer insulating film, a bottom of the first wiring trench not reaching a bottom of the first interlayer insulating film;
- a first via hole formed in the first interlayer insulating film and extending from a bottom of the first wiring trench to the bottom of the first interlayer insulating film;
- a capacitor recess formed in the first interlayer insulating film and reaching the bottom of the first interlayer insulating film;
- a first conductive member embedded in the first wiring trench and the first via hole; and
- a capacitor embedded in the capacitor recess and including a lower electrode, a capacitor dielectric film and an upper electrode, wherein the lower electrode of the capacitor is made of a same material as a material of the first conductive member and disposed along a bottom surface and a side surface of the capacitor recess, a concave portion is formed on an upper surface of the lower electrode, the capacitor dielectric film covers an inner surface of the concave portion formed on the upper surface of the lower electrode, and the upper electrode is embedded in the concave portion.
- According to another aspect of the present invention, there is provided a method of manufacturing a semiconductor device comprising steps of:
- (a) forming a first interlayer insulating film over a semiconductor substrate;
- (b) forming, in the first interlayer insulating film, a first wiring trench reaching partway in a depth direction of the first interlayer insulating film, a first via hole extending from a bottom of the first wiring trench to a bottom of the first interlayer insulating film and a capacitor recess extending from an upper surface to the bottom surface of the first interlayer insulating film;
- (c) depositing a lower conductive film under a condition that the first wiring trench and the first via hole are fully filled with the lower conductive film and the lower conductive film has a thickness allowing an upper surface of the lower conductive film positions lower than the upper surface of the first interlayer insulating film in a partial area of the capacitor recess;
- (d) forming a capacitor dielectric film over the lower conductive film;
- (e) depositing an upper conductive film over the capacitor dielectric film;
- (f) removing the lower conductive film, the capacitor dielectric film and the upper conductive film disposed above the upper surface of the first interlayer insulating film to leave a first conductive member consisting of a portion of the lower conductive film in the first wiring trench and in the first via hole and a capacitor in the capacitor recess, the capacitor being a lamination of a portion of the lower conductive film, a portion of the capacitor dielectric film and a portion of the upper conductive film.
- A capacitor can be manufactured without adding a new photolithography process. By adjusting a thickness of the lower conductive film, it becomes possible to adjust a width of the upper surface of the capacitor lower electrode made of a portion of the lower conductive film.
-
FIGS. 1A to 1O are cross sectional views of a semiconductor device during manufacture according to a first embodiment. -
FIG. 1P is a cross sectional view of the semiconductor device according to the first embodiment. -
FIG. 2 is a plan view of the semiconductor device according to the first embodiment. -
FIG. 3 is a cross sectional view of the semiconductor device according to a second embodiment. -
FIG. 4 is a plan view of the semiconductor device according to the second embodiment. -
FIG. 5 is a cross sectional view of the semiconductor device according to a third embodiment. -
FIG. 6 is a plan view of the semiconductor device according to the third embodiment. -
FIG. 7 is a plan view of a semiconductor device according a modification of the third embodiment. -
FIG. 8 is a plan view of the semiconductor device according to the modification of the third embodiment. -
FIG. 9 is a cross sectional view of the semiconductor device according to a fourth embodiment. -
FIG. 10 is a plan view of the semiconductor device according to the fourth embodiment. -
FIGS. 11A and 11B are cross sectional views of a semiconductor device during manufacture according to a comparative example. -
FIGS. 12A and 12B are cross sectional views of a semiconductor device during manufacture according to a fifth embodiment. -
FIGS. 13A and 13B are cross sectional views of a semiconductor device during manufacture according to a sixth embodiment. -
FIGS. 14A and 14B are cross sectional views of a semiconductor device during manufacture according to a seventh embodiment. -
FIG. 15 is a cross sectional view of a semiconductor device during manufacture according to an eighth embodiment. -
FIG. 16 is a cross sectional view of a semiconductor device with a conventional capacitor. -
FIGS. 17A to 17D are cross sectional views of a semiconductor device with a conventional capacitor during manufacture. -
FIGS. 18A and 18B are cross sectional views of a semiconductor device with a conventional capacitor during manufacture. - With reference to
FIGS. 1A to 1Q , description will be made on a semiconductor device manufacture method according to the first embodiment. - As shown in
FIG. 1A , anisolation insulating film 2 of a shallow trench isolation (STI) structure is formed in a surface layer of asemiconductor substrate 1 made of silicon. AMOSFET 3 is formed in an active region defined by theisolation insulating film 2. Anetching stopper film 4 of SiN is formed on the surface of thesemiconductor substrate 1, coveringMOSFET 3. A first-layerinterlayer insulating film 5 of phosphosilicate glass (PSG) or the like is formed on theetching stopper film 4. Viaholes interlayer insulating film 5 andetching stopper film 4, and plugs 8 and 9 made of W or the like are embedded in the via holes 6 and 7, respectively. Theplugs MOSFET 3, respectively. The inner surfaces of the via holes 6 and 7 are covered with a barrier metal film of TiN or the like. - On the first-layer
interlayer insulating film 5, a second-layerinterlayer insulating film 13 is formed. The second-layerinterlayer insulating film 13 consists of three layers: anetching stopper film 10 of SiC or the like, an insulatingfilm 11 of SiOC or the like and acap film 12 of SiO2. A plurality ofwiring trenches 15 are formed in theinterlayer insulating film 13. The inner surfaces of thewiring trenches 15 are covered with barrier metal films of Ta or the like, and the insides of thewiring trenches 15 are filled with conductive members made of copper. Theconductive members 16 in thewiring trenches 15 constitute first-layer wirings. Thewiring trenches 15 andconductive members 16 are formed by a single damascene method. - On the second-layer
interlayer insulating film 13, a third-layerinterlayer insulating film 23 is formed. The third-layerinterlayer insulating film 23 consists of three layers of anetching stopper film 20 of SiC or the like, an insulatingfilm 21 of SIOC or the like and acap film 22 of SiO2. A plurality ofwiring trenches 25 and viaholes 26 are formed in theinterlayer insulating film 23. The inner surfaces of thewiring trench 25 and viahole 26 are covered with a barrier metal film of Ta or the like, and the inside thereof is filled with aconductive member 28 of copper. Theconductive member 28 in thewiring trench 25 constitutes a wiring, and theconductive member 28 in the viahole 26 constitutes an interconnect portion between the upper and lower wirings. Thewiring trench 25, viahole 26 andconductive member 28 are formed by a dual damascene method. - On the third-layer
interlayer insulating film 23, a plurality of wiring layers are formed having a structure similar to that of the third-layer wiring structure. - An interlayer insulating
film 44 of a four-layer structure is formed on thewiring layer 30. Theinterlayer insulating film 44 has a lamination structure of anetching stopper film 40 of SiN having a thickness of 50 nm, a vialayer insulating film 41 of SiO2 having a thickness of 350 nm, anetching stopper film 42 of SiN having a thickness of 50 nm and a Wiringlayer insulating film 43 of SiO2 having a thickness of 350 nm stacked in this order. These films are deposited by, e.g., chemical vapor deposition (CVD). - As shown in
FIG. 1B , a wiring trench and a via hole are formed in theinterlayer insulating film 44 by a damascene method, and a conductive member of copper or copper alloy is embedded in the wiring trench and via hole.FIGS. 1B to 1N show only the lamination structure above thewiring layer 30. Aconductive member 45 is embedded in a recess formed in the wiringlayer insulating film 43 andetching stopper film 42 in the region where a capacitor is to be formed. In other regions, wirings 46 and 47 are disposed. For example, thewiring 47 is connected to a lower level wiring via a via hole passing through the vialayer insulating film 41 andetching stopper film 40. The inner surfaces of the wiring trench and via hole are covered with a barrier metal film of Ta or the like having a thickness of 30 nm. - As shown in
FIG. 1C , aninterlayer insulating film 54 of a four-layer structure is formed on theinterlayer insulating film 44. Theinterlayer insulating film 54 consists of anetching stopper film 50 of SiN having a thickness of 50 nm, a vialayer insulating film 51 of SiO2 having a thickness of 750 nm, anetching stopper film 52 of SiN having a thickness of 50 nm and a wiringlayer insulating film 53 of SiO2 having a thickness of 350 nm stacked in this order. These films are deposited by, e.g., plasma enhanced CVD. The vialayer insulating film 51 may be formed thicker than a targeted thickness, and thereafter the surface thereof is planarized by CMP to form the vialayer insulating film 51 having a targeted thickness. - A resist
film 57 is formed on theinterlayer insulating film 54. This resistfilm 57 is exposed and developed to formopenings opening 57A is disposed at the position corresponding to theconductive member 45 formed in the lower levelinterlayer insulating film 44, i.e., at the position where a capacitor is to be formed, and the plan shape and size thereof are a rectangle having a shorter side length of about 5 μm. Theother opening 57B corresponds to a via hole to be formed in the vialayer insulating film 51, and the plan shape and size thereof are a square having a side length of about 0.5 μm. - By using the resist
mask 57 as a mask, etching is performed down to the upper surface of theetching stopper film 50 by plasma etching using CF-based gas. The wiringlayer insulating film 53,etching stopper film 52 and vialayer insulating film 51 are etched under the conditions suitable for these film materials. After etching, the resistmask 57 is removed by plasma ashing using O2 gas. - As shown in
FIG. 1D , arecess 51A is therefore formed in the region where a capacitor is to be formed, and a viahole 51B is formed in another region. - As shown in
FIG. 1E , resin is coated on the substrate and partially melted by wet etching, plasma etching or the like to leaveprotective members recess 51A and viahole 51B. - As shown in
FIG. 1F , a resistfilm 58 is formed on theinterlayer insulating film 54, andopenings opening 58A has a shape and size including therecess 51A where a capacitor is to be disposed as viewed in plan. Theopenings layer insulating film 53. Theopening 58B partially overlaps with the viahole 51B as viewed in plan. - As shown in
FIG. 1G , by using the resistfilm 58 having the openings as a mask, the wiringlayer insulating film 53 is etched by plasma etching using CF-based gas until theetching stopper film 52 is exposed. In this case, theprotective members etching stopper film 50 on the bottoms of therecess 51A and viahole 51B. Arecess 53A, andwiring trenches layer insulating film 53. - As shown in
FIG. 1H , the resistfilm 58 andprotective members - As shown in
FIG. 1I , theetching stopper films recesses wiring trenches hole 51B are removed. Theetching stopper films capacitor recess 55 is therefore formed having a two-step structure constituted of therecesses recesses capacitor recess 55. - As shown in
FIG. 1J , abarrier metal film 60 of Ta having a thickness of 30 nm is formed on the whole substrate surface by sputtering. Thebarrier metal film 60 may be made of TaN, TiN or the like. A seed film of copper having a thickness of 100 nm is formed on thebarrier metal film 60 by sputtering. By using this seed film as an electrode, copper is electroplated to deposit a lowerconductive film 62. A thickness of the lowerconductive film 62 is set in such a manner that the insides of thewiring trench 53B, viahole 51B andwiring trench 53C are completely filled with the lower conductive film. - Since the
capacitor recess 55 has a plan shape wider than that of the wiring trench and via hole, the inside thereof cannot be completely buried. A partial upper surface of the lowerconductive film 62 deposited in the vialayer portion 51A of thecapacitor recess 55 becomes lower than the upper surface of the wiringlayer insulating film 53. This is because thecapacitor recess 55 is deeper than thewiring trenches hole 51B is equal to a depth of thecapacitor recess 55, the size of the plan shape of the viahole 51B is smaller than the thickness of the vialayer insulating film 51, so that the viahole 51B is completely filled through isotropic growth. A region outside of the vialayer portion 51A of thecapacitor recess 55 and inside of thewiring layer portion 53A as viewed in plan is completely filled with the lowerconductive film 62. - As shown in
FIG. 1K , adielectric film 65 of SiN having a thickness of 50 nm is formed on the lowerconductive film 62 by plasma enhanced CVD. Thedielectric film 65 may be made of insulating material different from SiN, such as SiC, SiCN or the like. The dielectric film may have a two-layer structure of an oxide insulating layer of Ta, Hf, Al or the like and an insulating layer of SiN, SiC, SICN or the like. - A
barrier metal film 66 of Ta having a thickness of 30 nm is formed on thedielectric film 65 by sputtering. A copper seed film is formed on thebarrier metal film 66 and copper is electroplated to form an upperconductive film 68 having a thickness of 900 nm. The space in thecapacitor recess 55 still not filled is completely filled with the upperconductive film 68. The lowerconductive film 62 and upperconductive film 68 may be made of metal different from copper, such as aluminum (Al), silver (Ag) or the like. - As shown in
FIG. 1L , CMP is performed until the upper surface of the wiringlayer insulating film 53 is exposed. This CMP method will be described in the following. First, CMP is performed until thebarrier metal 66 shown inFIG. 1K is exposed, under the condition that theupper electrode film 68 can be easily and selectively polished relative to thebarrier metal film 66. Next, by changing the polishing conditions, thebarrier metal film 66 anddielectric film 65 are polished. Next, CMP is performed until thebarrier metal 60 is exposed, under the condition that the lowerconductive film 62 can be easily and selectively polished relative to thebarrier metal film 60. Lastly, thebarrier metal film 60 is polished to expose the wiringlayer insulating film 53. Under the condition that the five layers from thebarrier metal film 60 to upperconductive film 68 can be polished generally at an equal rate, CMP may be performed until the wiringlayer insulating film 53 is exposed, without changing the polishing conditions. - A
capacitor 69 is therefore formed being constituted of alower electrode 62A consisting of a portion of the lowerconductive film 62 left in thecapacitor recess 55, acapacitor dielectric film 65A consisting of a portion of thedielectric film 65 and anupper electrode 68A consisting of a portion of the upperconductive film 68. Awiring 62B consists of a portion of the lowerconductive film 62 left in thewiring trench 53B and viahole 51B, and awiring 62C consists of a portion of the lowerconductive film 62 left in thewiring trench 53C. - As viewed in plan, the
upper electrode 68A of thecapacitor 69 is located within the vialayer portion 51A of thecapacitor recess 55. Thebarrier metal film 60A andlower electrode 62A embedded in thewiring layer portion 53A in a region outside the vialayer portion 51A has the same lamination structure as thebarrier metal film 60C andwiring 62C in theother wiring trench 53C formed in the wiringlayer insulating film 53. - As shown in
FIG. 1M , aninterlayer insulating film 72 is formed on theinterlayer insulating film 54. Theinterlayer insulating film 72 has a two-layer structure of anetching stopper film 70 of SiN having a thickness of 70 nm and a vialayer insulating film 71 of SiO2 having a thickness of 900 nm stacked in this order. The surface of the vialayer insulating film 71 is planarized by CMP. - As shown in
FIG. 1N , viaholes interlayer insulating film 72. Theupper electrode 68A of thecapacitor 69 is therefore exposed on the bottom of the viahole 71D, and thelower electrode 62A is exposed on the bottom of the viahole 71A. Thewiring 62B is exposed on the bottom of the viahole 71B. As viewed in plan, the viahole 71A is disposed at a position outside the vialayer portion 51A of thecapacitor recess 55 and partially superposing upon thewiring layer portion 53A. - As shown in
FIG. 1O , a barrier metal film is formed covering the inner surfaces of the via holes 71D, 71A and 71B, and plugs 73D, 73A and 73B of tungsten (W) are embedded in the via holes 71D, 71A and 71B. The barrier metal film is made of TiN, WN, WSiN or the like.Wirings interlayer insulating film 72. Each of these wirings consists of a lower barrier metal film having a lamination structure of a Ti film and a TiN film and a thickness of 50 nm, a main portion made of aluminum (Al) or copper-added aluminum (AlCu) having a thickness of 900 nm and an upper barrier metal film having a lamination structure of a Ti film and a TiN film and a thickness of 50 nm. The wirings 75D, 75A and 75B are connected to theplugs - As shown in
FIG. 1P , aninterlayer insulating film 80 of SiO2 having a thickness of 900 nm is formed on the whole substrate surface, and acover film 81 of SiN having a thickness of 500 nm is formed on theinterlayer insulating film 80. Openings (not shown) are formed through theinterlayer insulating film 80 andcover film 81 to expose the pads. -
FIG. 2 is a plan view of the capacitor in the semiconductor device according to the first embodiment. A cross sectional view taken along one-dot chain line A1-A1 shown inFIG. 2 corresponds to the cross sectional views shown inFIGS. 1A to 1P . Theconductive member 45 is disposed in the interlayer insulating film below thecapacitor 69. The vialayer portion 51A of thecapacitor recess 55 is located within theconductor member 45, and theupper electrode 68A is located within the vialayer portion 51A. Since the plan shape of theupper electrode 68A is not defined by photolithography, an exposure mask is not used for theupper electrode 68A. Thewiring layer portion 53A includes the vialayer portion 51A therein. - A plurality of via
holes 71D for connection to thewiring 75D are disposed within theupper electrode 68A. A plurality of viaholes 71A for connection to thewiring 75A are disposed inside thewiring layer portion 53A of thecapacitor recess 55 and outside the vialayer portion 51A. - In the first embodiment, the via
layer portion 51A of thecapacitor recess 55 is formed at the same time when the viahole 51B is formed in the process shown inFIG. 1D . Thewiring layer portion 53A is formed at the same time when thewiring trenches FIG. 1G . Therefore, it is not necessary to prepare a mask pattern for exclusive use for forming the capacitor. Furthermore, the size of the region between an outer periphery of the vialayer portion 51A of thecapacitor recess 55 shown inFIG. 2 and an outer periphery of thewiring portion 53A can be set as desired by mask pattern designs. In this region, the upper flat surface of thelower electrode 62A of thecapacitor 69 is disposed. It is therefore possible to easily align the position of the via holes 71A for connection between thelower electrode 62A andupper wiring 75A. -
FIG. 3 is a cross sectional view of a semiconductor device of the second embodiment. Description will be made by paying attention to different points from the semiconductor device of the first embodiment shown inFIG. 1P . In the second embodiment, theconductive member 45 is not disposed below thecapacitor 55 shown inFIG. 1P . Further, theplug 73A andwiring 75A connected to the upper surface of thelower electrode 62A of acapacitor 69 are not disposed. If thelower electrode 62A of thecapacitor 69 has sufficiently low resistance, the supplementaryconductive member 45 is not required to be disposed. -
FIG. 4 is a plan view of the semiconductor device of the second embodiment. A cross sectional view taken along one-dot chain line A3-A3 in FIG. 4 corresponds toFIG. 3 . As shown in this cross sectional view, awiring 62L is disposed in place of thewiring 75A of the semiconductor device of the first embodiment shown inFIG. 2 . Thewiring 62L is embedded in awiring trench 53L formed in the wiringlayer insulating film 53 in which thewiring portion 53A of thecapacitor recess 55 is formed. Theelectrode lead wiring 62L can be disposed in this manner in the same layer as that of thelower electrode 62A. -
FIG. 5 is a cross sectional view of a semiconductor device of the third embodiment. Description will be made by paying attention to different points from the semiconductor device of the first embodiment shown inFIG. 1P . In the third embodiment, the side surfaces of thewiring portion 53A and vialayer portion 51A of thecapacitor recess 55 are flush with each other in the cross sectional view shown inFIG. 5 . Theplug 73A andupper level wiring 75A connected to thelower electrode 62A on the upper surface thereof are not disposed. -
FIG. 6 is a plan view of the semiconductor device of the third embodiment. A cross sectional view taken along one-dot chain line A5-A5 inFIG. 6 corresponds toFIG. 5 . As shown in this cross sectional view, the outer peripheries of the vialayer portion 51A andwiring portion 53A of thecapacitor recess 55 coincide with each other. Awiring 45L is disposed in place of thewiring 75A connected to thelower electrode 62A. Thewiring 45L is embedded in a wiring trench formed in theinterlayer insulating film 44 in which theconductive member 45 is disposed, and is continuous with theconductive member 45. As described above, theelectrode lead wiring 45L can be disposed in theinterlayer insulating film 44 under thecapacitor 69. - As shown in
FIG. 7 , a mask pattern, in which anopening 58A of the resistfilm 58 for forming thewiring layer portion 53A of thecapacitor recess 55 is located within the vialayer portion 51A, may be used. In this case, in the process shown inFIG. 1F , since theopening 58A of the resistfilm 58 is smaller than the vialayer portion 51A, theprotective member 56A is exposed on the whole bottom of theopening 58A. In the process shown inFIG. 1G , the wiringlayer insulating film 53 where the capacitor is to be disposed is not etched. Therefore, thecapacitor recess 55 has a side surface without a step. - As shown in
FIG. 8 , theopening 58A for forming thewiring layer portion 53A shown inFIG. 7 may not be formed. Also in this case, thecapacitor recess 55 is formed having the same structure as that shown inFIG. 7 . -
FIG. 9 is a cross sectional view of a semiconductor device of the fourth embodiment. Description will be made by paying attention to different points from the semiconductor device of the third embodiment shown inFIGS. 5 and 6 . Also in the fourth embodiment, as in the case of the third embodiment, a step is not formed on the side surface of thecapacitor recess 55 as shown in the cross sectional view shown inFIG. 9 . In the fourth embodiment, theconductive member 45 disposed below thecapacitor 69 shown inFIG. 5 is not formed. Instead, thelower electrode 62A of thecapacitor 69 is connected to anupper level wiring 75A via aplug 73B in a viahole 71A formed in the upperinterlayer insulating film 72. -
FIG. 10 is a plan view of the semiconductor device of the fourth embodiment. A cross sectional view taken along one-dot chain line A9-A9 inFIG. 10 corresponds toFIG. 9 . The viahole 71A does not overlap with theupper electrode 68A, but is disposed so as to overlap with the vialayer portion 51A of thecapacitor recess 55. If a width from the outer periphery of the vialayer portion 51A to the border of theupper electrode 68A is about 700 nm, position alignment of the viahole 71A can be performed at a sufficient precision. In order to satisfy this condition, it is sufficient if the thickness of the lowerconductive film 62 shown inFIG. 1J is about 700 nm. In this embodiment, since the thickness of the interlayer insulating film 54 (a depth of the capacitor recess 55) is 1200 nm, even if the thickness of the lowerconductive film 62 is set to about 700 nm, a partial upper surface of the lowerconductive film 62 is lower than the upper surface of theinterlayer insulating film 54. - Next, with reference to
FIGS. 11A to 12B , the fifth embodiment will be described. InFIG. 1K of the first embodiment, the surface of the lowerconductive film 62 formed by electroplating copper directly reflects the underlying stepwise shape, and the sidewalls of the concave portions formed on the surface of the lowerconductive film 62 cross the flat surface generally at a right angle. Depending upon electroplating conditions, a cross portion between the side surface and flat surface is rounded. Reflecting this round portion, the surfaces of thedielectric film 65 andbarrier metal film 66 are also rounded. Depending upon etching conditions for forming a recess in theinterlayer insulating film 54, the inner surface itself of thecapacitor recess 55 has a rounded portion where the side surface and flat surface are crossing with each other. In this case, reflecting this underlying rounded surface, the surface of the lowerconductive film 62 is rounded. -
FIG. 11A is a cross sectional view showing a structure in which the surface is rounded, where the flat surface and the side surface of the recess formed on the surface of the lowerconductive film 62 are crossing with each other. Anupper surface 92 of the lowerconductive film 62 is generally flush with the upper surface of the wiringlayer insulating film 53, above the portion where a bottom 90 of thewiring portion 53A of thecapacitor recess 55 and aside surface 91 of the vialayer portion 51A are crossing with each other. - As shown in
FIG. 11B , as CMP is performed down to the upper surface of the wiringlayer insulating film 53, rounded portions of thedielectric film 65 andbarrier metal film 66 are left in thecapacitor recess 55. Therefore, in the cross sectional view shown inFIG. 11B , a corner having an acute angle occurs at across portion 93 between an outer surface of thebarrier metal film 66A and the upper flat surface of thecapacitor 69. An electric field concentrates upon this corner, so that the breakdown voltage characteristics are degraded. -
FIG. 12A is a cross sectional view of a semiconductor device during manufacture according to the fifth embodiment. The lowerconductive film 62 is formed in such a manner that anupper surface 92 of the lowerconductive film 62 is higher than an upper surface of thewiring insulating film 53 by a predetermined value, above a portion where theside surface 91 of the vialayer portion 51A and thebottom surface 90 of thewiring layer portion 53A of thecapacitor recess 55 are crossing with each other. A rounded portion where theupper surface 92 and the side surface of a concave portion on the surface of the lowerconductive film 62 formed in the vialayer portion 51A of thecapacitor recess 55, positions above the upper surface of the wiringlayer insulating film 53. Therefore, the rounded portion can be removed by CMP. -
FIG. 12B shows the structure after CMP. The outer surface of thebarrier metal film 66A left in thecapacitor recess 55 and the upper flat surface of thecapacitor 69 are crossing with each other generally at a right angle. Since the corner having an acute angle shown inFIG. 11B is not formed, it is possible to suppress electric field concentration and avoid degradation of the breakdown voltage characteristics. - In order to prevent the corner having an acute angle from being formed, it is preferable that the lower
conductive film 62 is formed in such a manner that theupper surface 92 of the lowerconductive film 62 is higher than the upper surface of the wiringlayer insulating film 53 by 350 nm or more, in the structure shown inFIG. 12A . - Although the description concerns about avoiding disadvantages to be caused by a rounded portion where the flat surface and the side surface are crossing with each other, a rounded portion not only causes disadvantages but also provide the following advantages.
- Generally, if a film is formed on a surface having a flat surface and a side surface crossing with other generally at a right angle and not having a rounded portion, coverage may be lowered in some cases. An occurrence frequency of coverage defects can be lowered by forming a rounded portion where the flat surface and the side surface are crossing with other. For example, if an intersection between the bottom surface and the side surface of the
capacitor recess 55 is angulated and thebarrier metal film 60 is formed by sputtering, coverage at the right angle corner is generally degraded. By rounding the intersection, coverage of a film to be formed on this intersection can be suppressed from being lowered. - Next, with reference to
FIGS. 13A and 13B , a manufacture method for a semiconductor device according to the sixth embodiment will be described. -
FIG. 13A is a partially enlarged diagram showing the state after CMP of the first embodiment shown inFIG. 1L . At the last stage of CMP, CMP is performed under the condition that a polishing rate of thebarrier metal film layer insulating film 53,capacitor dielectric film 65A,lower electrode 62A andupper electrode 68A. In this case, the upper end of the border of thebarrier metal film 66A is lower than the upper end of the border of thecapacitor dielectric film 65A and the upper surface of theupper electrode 68A.Concave portions barrier metal films - As shown in
FIG. 13B , theconcave portions etching stopper film 70. In the structure shown inFIG. 1L , the upper end of the border of thebarrier metal film 66A is spaced from the border of the upper surface of thelower electrode 62A only by a thickness of thecapacitor dielectric film 65A. In the sixth embodiment shown inFIG. 13B , a distance between the upper end of the border of thebarrier metal film 66A and the border of the upper surface of thelower electrode 62A corresponds to sum of a thickness of thecapacitor dielectric film 65A and a depth of theconcave portion 96. - An interface between the
capacitor dielectric film 65A andetching stopper film 70 is likely to cause an increase in leak current and breakdown voltage degradation. In the sixth embodiment, a path on the interface from one electrode to the other electrode of thecapacitor 69 is elongated, so that it is possible to prevent an increase in leak current and breakdown voltage degradation. - Next, with reference to
FIGS. 14A and 14B , a manufacture method for a semiconductor device according to the seventh embodiment will be described. Description will be made by paying attention to different points from the sixth embodiments shown inFIGS. 13A and 13B . In the seventh embodiment, a polishing rate of thelower electrode 62A andupper electrode 68A is faster than a polishing rate of the wiringlayer insulating film 53,barrier metal film capacitor dielectric film 65A. -
FIG. 14A shows the structure after CMP. The upper ends of thecapacitor dielectric film 65A andbarrier metal film 66A protrude from the upper surface of thelower electrode 62A and the upper surface of theupper electrode 68A. -
FIG. 14B shows the structure after thebarrier metal film 70 is formed. In the seventh embodiment, a distance between the upper end of the border of thebarrier metal film 66A and the border of the upper surface of thelower electrode 62A corresponds to sum of a thickness of thecapacitor dielectric film 65A and a height from the upper surface of thelower electrode 62A to the upper end of thecapacitor dielectric film 65A. As in the case of the sixth embodiment, it is therefore possible to prevent an increase in leak current and breakdown voltage degradation. -
FIG. 15 is a cross sectional view showing a capacitor portion of a semiconductor device of the eighth embodiment. Description will be made by paying attention to different points from the semiconductor device of the fifth embodiment shown inFIGS. 12A and 12B . Description is omitted for the same constituent elements as those of the semiconductor device of the fifth embodiment. - In the fifth embodiment, the surface of the lower
conductive film 62 has rounded portions at the intersection between the region in conformity with the bottom surface and the region in conformity with the side surface of thecapacitor recess 55. As shown inFIG. 15 , depending upon the growth conditions for the lowerconductive film 62, a sloped surface is formed on the surface of the lowerconductive film 62 at the intersection between the region in conformity with the bottom surface and the side surface of thecapacitor recess 55. The sloped surface is formed particularly when the lowerconductive film 62 is deposited under the conditions that a narrow via hole is filled with the lowerconductive film 62 at good reproductivity. - Also in the case in which the sloped surface is formed, as in the case of the fifth embodiment shown in
FIG. 12A , it is preferable that the lowerconductive film 62 is formed in such a manner that theupper surface 92 of the lowerconductive film 62 is higher than the upper surface of the wiringlayer insulating film 53 by 350 to 400 nm or more. - In the above-described embodiments, although the via layer insulating film and wiring layer insulating film constituting the interlayer insulating film are made of SiO2, other insulating material may also be used, such as inorganic insulating materials SiOF, SiN, SiC, SiCN, SiON and the like or low dielectric constant organic insulating materials. Porous insulating materials may also be used. It is preferable to combine these materials and the material of the etching stopper film so as to ensure a sufficient etching selectivity.
- The present invention has been described in connection with the preferred embodiments. The invention is not limited only to the above embodiments. It will be apparent to those skilled in the art that other various modifications, improvements, combinations, and the like can be made.
Claims (19)
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US20100164066A1 (en) * | 2008-12-30 | 2010-07-01 | Stmicroelectronics S.R.L. | Integrated capacitor having a non-uniform thickness |
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Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
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US9264013B2 (en) | 2013-06-04 | 2016-02-16 | Qualcomm Incorporated | Systems for reducing magnetic coupling in integrated circuits (ICS), and related components and methods |
Citations (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5708559A (en) * | 1995-10-27 | 1998-01-13 | International Business Machines Corporation | Precision analog metal-metal capacitor |
US20020005583A1 (en) * | 2000-06-07 | 2002-01-17 | Mitsubishi Denki Kabushiki Kaisha | Semiconductor device and fabrication process therefor |
US6451688B1 (en) * | 2000-12-04 | 2002-09-17 | Fujitsu Limited | Method for manufacturing a semiconductor device |
US6452251B1 (en) * | 2000-03-31 | 2002-09-17 | International Business Machines Corporation | Damascene metal capacitor |
US20020155676A1 (en) * | 2001-04-19 | 2002-10-24 | Michael Stetter | Zero mask MIMcap process for a low k BEOL |
US20020179955A1 (en) * | 2001-05-30 | 2002-12-05 | Mitsubishi Denki Kabushiki Kaisha | Semiconductor device comprising MIM-type capacitor and method of manufacturing the same |
US20020185671A1 (en) * | 2001-06-12 | 2002-12-12 | Kim Si Bum | Semiconductor device having a metal insulator metal capacitor |
US20030060052A1 (en) * | 2001-09-27 | 2003-03-27 | Kim Sarah E. | Fabrication of 3-D capacitor with dual damascene process |
US20040009640A1 (en) * | 2001-08-17 | 2004-01-15 | Mukul Saran | High capacitance damascene capacitors |
US20040056324A1 (en) * | 2002-09-23 | 2004-03-25 | Ning Xian J. | MIM capacitor structures and fabrication methods in dual-damascene structures |
US20050024979A1 (en) * | 2003-07-29 | 2005-02-03 | Kim Yoon-Hae | Metal-insulator-metal capacitor and interconnecting structure |
US20060043452A1 (en) * | 2004-08-25 | 2006-03-02 | Mamoru Ueda | Ferroelectric memory and its manufacturing method |
US20060189090A1 (en) * | 2005-02-24 | 2006-08-24 | Jinsheng Yang | Method for fabricating a metal-insulator-metal capacitor |
US7332764B2 (en) * | 2004-06-11 | 2008-02-19 | Samsung Electronics Co., Ltd. | Metal-insulator-metal (MIM) capacitor and method of fabricating the same |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2001036010A (en) * | 1999-07-16 | 2001-02-09 | Toshiba Corp | Manufacture of semiconductor device |
JP2001177076A (en) * | 1999-12-16 | 2001-06-29 | Sony Corp | Semiconductor device and method of fabrication |
JP4309608B2 (en) * | 2001-09-12 | 2009-08-05 | 株式会社東芝 | Semiconductor device and manufacturing method thereof |
-
2006
- 2006-01-16 JP JP2006007658A patent/JP5055768B2/en not_active Expired - Fee Related
- 2006-08-22 US US11/507,438 patent/US20070164434A1/en not_active Abandoned
-
2012
- 2012-09-13 US US13/613,961 patent/US8759192B2/en active Active
Patent Citations (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5708559A (en) * | 1995-10-27 | 1998-01-13 | International Business Machines Corporation | Precision analog metal-metal capacitor |
US6008083A (en) * | 1995-10-27 | 1999-12-28 | International Business Machines Corporation | Precision analog metal-metal capacitor |
US6452251B1 (en) * | 2000-03-31 | 2002-09-17 | International Business Machines Corporation | Damascene metal capacitor |
US20020005583A1 (en) * | 2000-06-07 | 2002-01-17 | Mitsubishi Denki Kabushiki Kaisha | Semiconductor device and fabrication process therefor |
US6451688B1 (en) * | 2000-12-04 | 2002-09-17 | Fujitsu Limited | Method for manufacturing a semiconductor device |
US20020155676A1 (en) * | 2001-04-19 | 2002-10-24 | Michael Stetter | Zero mask MIMcap process for a low k BEOL |
US20020179955A1 (en) * | 2001-05-30 | 2002-12-05 | Mitsubishi Denki Kabushiki Kaisha | Semiconductor device comprising MIM-type capacitor and method of manufacturing the same |
US20020185671A1 (en) * | 2001-06-12 | 2002-12-12 | Kim Si Bum | Semiconductor device having a metal insulator metal capacitor |
US20040009640A1 (en) * | 2001-08-17 | 2004-01-15 | Mukul Saran | High capacitance damascene capacitors |
US20030060052A1 (en) * | 2001-09-27 | 2003-03-27 | Kim Sarah E. | Fabrication of 3-D capacitor with dual damascene process |
US20040056324A1 (en) * | 2002-09-23 | 2004-03-25 | Ning Xian J. | MIM capacitor structures and fabrication methods in dual-damascene structures |
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Also Published As
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JP5055768B2 (en) | 2012-10-24 |
US8759192B2 (en) | 2014-06-24 |
JP2007189161A (en) | 2007-07-26 |
US20130011995A1 (en) | 2013-01-10 |
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