US20010023116A1 - Method for setting the threshold voltage of a MOS transistor - Google Patents
Method for setting the threshold voltage of a MOS transistor Download PDFInfo
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- US20010023116A1 US20010023116A1 US09/811,799 US81179901A US2001023116A1 US 20010023116 A1 US20010023116 A1 US 20010023116A1 US 81179901 A US81179901 A US 81179901A US 2001023116 A1 US2001023116 A1 US 2001023116A1
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- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/28—Manufacture of electrodes on semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/268
- H01L21/28008—Making conductor-insulator-semiconductor electrodes
- H01L21/28017—Making conductor-insulator-semiconductor electrodes the insulator being formed after the semiconductor body, the semiconductor being silicon
- H01L21/28158—Making the insulator
- H01L21/28167—Making the insulator on single crystalline silicon, e.g. using a liquid, i.e. chemical oxidation
- H01L21/28202—Making the insulator on single crystalline silicon, e.g. using a liquid, i.e. chemical oxidation in a nitrogen-containing ambient, e.g. nitride deposition, growth, oxynitridation, NH3 nitridation, N2O oxidation, thermal nitridation, RTN, plasma nitridation, RPN
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- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/28—Manufacture of electrodes on semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/268
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- H01L21/28158—Making the insulator
- H01L21/28167—Making the insulator on single crystalline silicon, e.g. using a liquid, i.e. chemical oxidation
- H01L21/28176—Making the insulator on single crystalline silicon, e.g. using a liquid, i.e. chemical oxidation with a treatment, e.g. annealing, after the formation of the definitive gate conductor
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- H01L21/77—Manufacture or treatment of devices consisting of a plurality of solid state components or integrated circuits formed in, or on, a common substrate
- H01L21/78—Manufacture or treatment of devices consisting of a plurality of solid state components or integrated circuits formed in, or on, a common substrate with subsequent division of the substrate into plural individual devices
- H01L21/82—Manufacture or treatment of devices consisting of a plurality of solid state components or integrated circuits formed in, or on, a common substrate with subsequent division of the substrate into plural individual devices to produce devices, e.g. integrated circuits, each consisting of a plurality of components
- H01L21/822—Manufacture or treatment of devices consisting of a plurality of solid state components or integrated circuits formed in, or on, a common substrate with subsequent division of the substrate into plural individual devices to produce devices, e.g. integrated circuits, each consisting of a plurality of components the substrate being a semiconductor, using silicon technology
- H01L21/8232—Field-effect technology
- H01L21/8234—MIS technology, i.e. integration processes of field effect transistors of the conductor-insulator-semiconductor type
- H01L21/8238—Complementary field-effect transistors, e.g. CMOS
- H01L21/823828—Complementary field-effect transistors, e.g. CMOS with a particular manufacturing method of the gate conductors, e.g. particular materials, shapes
- H01L21/823842—Complementary field-effect transistors, e.g. CMOS with a particular manufacturing method of the gate conductors, e.g. particular materials, shapes gate conductors with different gate conductor materials or different gate conductor implants, e.g. dual gate structures
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- H01L27/08—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being a semiconductor body including only semiconductor components of a single kind
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- H01L29/40—Electrodes ; Multistep manufacturing processes therefor
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- H01L29/49—Metal-insulator-semiconductor electrodes, e.g. gates of MOSFET
- H01L29/51—Insulating materials associated therewith
- H01L29/511—Insulating materials associated therewith with a compositional variation, e.g. multilayer structures
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- H01L29/40—Electrodes ; Multistep manufacturing processes therefor
- H01L29/43—Electrodes ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
- H01L29/49—Metal-insulator-semiconductor electrodes, e.g. gates of MOSFET
- H01L29/51—Insulating materials associated therewith
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- H01L29/49—Metal-insulator-semiconductor electrodes, e.g. gates of MOSFET
- H01L29/4966—Metal-insulator-semiconductor electrodes, e.g. gates of MOSFET the conductor material next to the insulator being a composite material, e.g. organic material, TiN, MoSi2
Definitions
- the invention relates to a method for setting the threshold voltage in a MOS transistor, in particular during the fabrication of CMOS circuits.
- a MOS (Metal Oxide Semiconductor) transistor is a field-effect transistor having an insulated control electrode or gate for controlling a current channel in a substrate.
- the charge carrier density in the semiconductor substrate is controlled by the voltage present at the gate terminal. If a sufficiently high voltage, which exceeds a specific threshold voltage, is applied to the gate electrode, an inversion current channel is produced at the semiconductor surface between the drain terminal and the source terminal of the MOSFET (Metal Oxide Semiconductor Field Effect Transistor), and a current can flow through the inversion current channel.
- the gate voltage which is necessary to just form the inversion current channel, is referred to as the threshold voltage U T of the MOSFET.
- CMOS Complementary Metal Oxide Semiconductor
- CMOS Complementary Metal Oxide Semiconductor
- n-channel and p-channel MOS field-effect transistors are integrated simultaneously in the semiconductor substrate.
- an n-type well for example, is diffused into a p-conducting semiconductor substrate and a selective field oxidation is subsequently carried out in order to insulate the surfaces of the individual transistor regions from one another.
- a thin oxide layer is thereupon formed, which acts as a screen oxide or scatter oxide.
- the threshold voltages of the PMOS transistors and of the NMOS transistors are then set through the use of ion implantation.
- a further process step firstly the screen oxide is removed, then the gate oxide is produced and then polycrystalline silicon layers for the gate terminals are applied, and patterned, and, after electrical insulation of the gate stack from the drain and source regions through the use of a spacer, the diffusion of acceptors for the drain terminal and the source terminal of the PMOS transistor and a diffusion of donors for the drain terminal and source terminal of the NMOS transistor are carried out. After the contact windows have been opened by etching the drain and source regions, contacts can be made.
- the coordination of the threshold voltage U T of the PMOS transistor and of the NMOS transistor complementary thereto in the CMOS circuit is of particular importance here since the threshold voltage of the two complementary transistors should be identical.
- the threshold voltage depends on the work function at the gate terminals. Work function refers to the energy required to release an electron from a crystal lattice.
- the gate electrodes are conventionally formed from crystalline polysilicon. The work function and thus the threshold voltage U T of the MOSFETs are in this case set by doping the polycrystalline silicon.
- the threshold voltages U T of the two complementary MOSFETs can be made the same in the conventional fabrication method. In this case, the threshold voltage U T typically lies between 0.5 volt and 0.7 volt.
- a simpler and more cost-effective variant is to dope the polysilicon for both transistor types at an earlier point, for example when performing the deposition.
- a disadvantage is that the functionality of the “buried channel PMOS” is then reduced.
- a method for setting a threshold voltage of a MOS transistor includes the steps of:
- the invention provides a method for setting the threshold voltage in a MOS transistor having a gate composed of polysilicon, wherein germanium ions are implanted into the gate in order to change the work function of the gate composed of polysilicon.
- the gate implanted with germanium ions is subsequently heat-treated for annealing purposes or subjected to a thermal treatment by being exposed to a high temperature for a predetermined period of time.
- nitrogen ions are implanted into the gate composed of polysilicon before germanium ions are implanted.
- the gate composed of polysilicon is heat-treated or subjected to thermal treatment for annealing purposes by being exposed to a high temperature for a specific period of time.
- the method is preferably used for setting the threshold voltage of a PMOS transistor or an NMOS transistor in a CMOS circuit.
- the temperature for thermal treatment of the gate after implantation is preferably above 1000° C.
- the proportion of germanium which is implanted into the gate composed of polysilicon is preferably about 20%.
- FIG. 1 is a diagrammatic, partial sectional view of the layer structure in a MOS transistor whose threshold voltage is set by the method according to the invention
- FIG. 2 is a diagrammatic, partial sectional view of a p-channel MOS field-effect transistor whose threshold voltage is set by the method according to the invention.
- FIG. 3 is a diagrammatic, partial sectional view of a CMOS structure in which the threshold voltage of the PMOS transistor is set by the method according to the invention.
- a gate dielectric 2 is applied on a semiconductor substrate 1 by thermal oxidation of the substrate 1 or by a deposition method.
- the dielectric 2 is preferably composed of an oxide having a relatively high dielectric constant.
- the gate dielectric 2 may also be fabricated from silicon nitride.
- Polycrystalline silicon is subsequently applied on the gate dielectric 2 in order to form a gate control electrode.
- Nitrogen ions are implanted into this polysilicon layer by ion implantation.
- the polysilicon implanted with nitrogen ions is subsequently heat-treated by being exposed to a high temperature of above 1000° C.
- germanium ions are subsequently implanted into the remaining polysilicon layer situated above the oxidation barrier layer, in order to change the work function of the gate composed of polysilicon.
- the implantation of the germanium ions initially produces an amorphous silicon layer, which is converted into a polycrystalline silicon-germanium compound by subsequent heat treatment or annealing at above 1000° C. in a furnace.
- the germanium-doped polysilicon layer 4 forms the gate terminal of the MOS transistor, the threshold voltage U T , at which an inversion layer forms in the substrate 1 , being set by the percentage proportion of germanium in the polysilicon.
- FIG. 2 shows a PMOS transistor having a gate terminal G, a source terminal S, and a drain terminal D and whose threshold voltage U T is set by the implantation of germanium ions in the gate.
- the PMOS transistor has an n-doped semiconductor substrate 1 , with a p + -doped drain region 5 and a p + -doped source region 6 . Electrical contact is made with the drain region 5 and the source region 6 respectively via terminals 7 , 8 composed of polysilicon.
- the semiconductor substrate 1 is covered with field oxide 9 .
- the method according to the invention for setting the threshold voltage of a MOS transistor is suitable in particular for setting the threshold voltage U T of MOS transistors in a CMOS fabrication method.
- FIG. 3 shows a CMOS circuit having a PMOS transistor and an NMOS transistor complementary thereto.
- the NMOS transistor has a gate 10 which is composed of polysilicon and is isolated from a p-doped well region 12 by a dielectric 11 .
- the p-doped well 12 is situated in the n-doped semiconductor substrate 1 .
- the NMOS transistor has an n + -doped drain region 13 and an n + -doped source region 14 . Electrical contact can be made with the drain region 13 and the source region 14 respectively via polysilicon terminals 15 , 16 .
- the threshold voltage U TP of the PMOS transistor can be made the same as the threshold voltage U TN of the NMOS transistor.
- the threshold voltage U TN of the NMOS transistor is achieved, as in the conventional fabrication methods, by n + -doping of the gate 10 composed of polysilicon.
- the implantation of germanium ions into the polysilicon layer is effected only in the region of the PMOS transistor and not in the region of the NMOS transistor.
- a high concentration of germanium ions in the SiGe gate 4 at the interface with the underlying dielectric 2 leads to a major influence on the work function and thus to a major change in the threshold voltage.
- the doping concentration of the germanium ions and thus the threshold voltage U T can be set very accurately through the use of the ion implantation.
- concentration profiles can be controlled to the greatest possible extent according to form and position by varying the energy and direction of incidence of the implanted germanium ions.
- the process temperatures can be kept low enough to preclude indiffusion of damaging contaminants.
- the structural changes caused by the ion implantation in the semiconductor crystal can be compensated by subsequent annealing by thermal treatment.
- the method according to the invention improves the short-channel properties of the PMOS transistor without having to change the fabrication method for the NMOS transistor.
- the gate 10 composed of polysilicon—of the NMOS transistor and the silicon gate 4 —implanted with germanium ions—of the PMOS transistor are fabricated in a deposition and etching process, as a result of which the fabrication process of a CMOS structure is considerably simplified.
- a two-stage polysilicon deposition with germanium implantation with subsequent annealing can be carried out after each deposition.
- the implantation with germanium ions after the second deposition simultaneously destroys the silicon oxide which has formed between the deposition processes.
- a two-stage polysilicon deposition with implantation of germanium ions and subsequent annealing leads to an improvement of germanium depletion effects at the gate/gate oxide interface.
- the implantation of nitrogen ions for forming an oxidation barrier layer prevents the formation of a germanium oxide layer on the gate oxide surface. This can also be achieved by implanting halogen ions.
Abstract
Description
- 1. Field of the Invention
- The invention relates to a method for setting the threshold voltage in a MOS transistor, in particular during the fabrication of CMOS circuits.
- A MOS (Metal Oxide Semiconductor) transistor is a field-effect transistor having an insulated control electrode or gate for controlling a current channel in a substrate. In this case, the charge carrier density in the semiconductor substrate is controlled by the voltage present at the gate terminal. If a sufficiently high voltage, which exceeds a specific threshold voltage, is applied to the gate electrode, an inversion current channel is produced at the semiconductor surface between the drain terminal and the source terminal of the MOSFET (Metal Oxide Semiconductor Field Effect Transistor), and a current can flow through the inversion current channel. The gate voltage, which is necessary to just form the inversion current channel, is referred to as the threshold voltage UT of the MOSFET. In CMOS (Complimentary Metal Oxide Semiconductor) technology, n-channel and p-channel MOS field-effect transistors are integrated simultaneously in the semiconductor substrate. In a conventional CMOS fabrication method, an n-type well, for example, is diffused into a p-conducting semiconductor substrate and a selective field oxidation is subsequently carried out in order to insulate the surfaces of the individual transistor regions from one another. A thin oxide layer is thereupon formed, which acts as a screen oxide or scatter oxide. The threshold voltages of the PMOS transistors and of the NMOS transistors are then set through the use of ion implantation. In a further process step, firstly the screen oxide is removed, then the gate oxide is produced and then polycrystalline silicon layers for the gate terminals are applied, and patterned, and, after electrical insulation of the gate stack from the drain and source regions through the use of a spacer, the diffusion of acceptors for the drain terminal and the source terminal of the PMOS transistor and a diffusion of donors for the drain terminal and source terminal of the NMOS transistor are carried out. After the contact windows have been opened by etching the drain and source regions, contacts can be made.
- The coordination of the threshold voltage UT of the PMOS transistor and of the NMOS transistor complementary thereto in the CMOS circuit is of particular importance here since the threshold voltage of the two complementary transistors should be identical. The threshold voltage depends on the work function at the gate terminals. Work function refers to the energy required to release an electron from a crystal lattice. The gate electrodes are conventionally formed from crystalline polysilicon. The work function and thus the threshold voltage UT of the MOSFETs are in this case set by doping the polycrystalline silicon. By n-doping the gate electrode of the NMOS transistor and by p-doping the gate electrode of the PMOS transistor, the threshold voltages UT of the two complementary MOSFETs can be made the same in the conventional fabrication method. In this case, the threshold voltage UT typically lies between 0.5 volt and 0.7 volt.
- The previous methods for setting the threshold voltages in NMOS transistors in CMOS fabrication technology have the disadvantage, however, that, on account of the different doping of the gate of the NMOS transistor and of the PMOS transistor, different dopants have to be provided and, furthermore, additional cost-intensive method steps for the masking and implantation of the different gate dopings are necessary.
- A simpler and more cost-effective variant is to dope the polysilicon for both transistor types at an earlier point, for example when performing the deposition. A disadvantage is that the functionality of the “buried channel PMOS” is then reduced.
- It is accordingly an object of the invention to provide a simple method for setting the threshold voltage in MOS transistors which overcomes the above-mentioned disadvantages of the heretofore-known methods of this general type and which allows to accurately set the threshold voltage through the use of a very small number of process steps.
- With the foregoing and other objects in view there is provided, in accordance with the invention, a method for setting a threshold voltage of a MOS transistor, the method includes the steps of:
- providing a gate for a MOS transistor, the gate being formed of polysilicon; and
- implanting germanium ions into the gate for changing a work function of the gate.
- In other words, the invention provides a method for setting the threshold voltage in a MOS transistor having a gate composed of polysilicon, wherein germanium ions are implanted into the gate in order to change the work function of the gate composed of polysilicon.
- Preferably, the gate implanted with germanium ions is subsequently heat-treated for annealing purposes or subjected to a thermal treatment by being exposed to a high temperature for a predetermined period of time.
- This has the particular advantage that a crystalline gate structure is achieved.
- In a particularly preferred mode of the invention, nitrogen ions are implanted into the gate composed of polysilicon before germanium ions are implanted.
- This has the particular advantage that a thin layer composed of a silicon-nitrogen compound is formed between the gate and an underlying gate oxide, and prevents the formation of a germanium oxide layer.
- Preferably, after the implantation of the nitrogen ions, the gate composed of polysilicon is heat-treated or subjected to thermal treatment for annealing purposes by being exposed to a high temperature for a specific period of time.
- The method is preferably used for setting the threshold voltage of a PMOS transistor or an NMOS transistor in a CMOS circuit.
- The temperature for thermal treatment of the gate after implantation is preferably above 1000° C.
- The proportion of germanium which is implanted into the gate composed of polysilicon is preferably about 20%.
- Other features which are considered as characteristic for the invention are set forth in the appended claims.
- Although the invention is illustrated and described herein as embodied in a method for setting the threshold voltage in MOS transistors, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
- The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
- FIG. 1 is a diagrammatic, partial sectional view of the layer structure in a MOS transistor whose threshold voltage is set by the method according to the invention;
- FIG. 2 is a diagrammatic, partial sectional view of a p-channel MOS field-effect transistor whose threshold voltage is set by the method according to the invention; and
- FIG. 3 is a diagrammatic, partial sectional view of a CMOS structure in which the threshold voltage of the PMOS transistor is set by the method according to the invention.
- Referring now to the figures of the drawings in detail and first, particularly, to FIG. 2 thereof, there is shown that firstly a gate dielectric2 is applied on a
semiconductor substrate 1 by thermal oxidation of thesubstrate 1 or by a deposition method. In this case, the dielectric 2 is preferably composed of an oxide having a relatively high dielectric constant. As an alternative, the gate dielectric 2 may also be fabricated from silicon nitride. Polycrystalline silicon is subsequently applied on the gate dielectric 2 in order to form a gate control electrode. Nitrogen ions are implanted into this polysilicon layer by ion implantation. The polysilicon implanted with nitrogen ions is subsequently heat-treated by being exposed to a high temperature of above 1000° C. for a predetermined period of time. As a result, an oxidation barrier layer 3 including silicon and nitrogen is produced at the interface between the polysilicon layer and the gate dielectric 2. Germanium ions are subsequently implanted into the remaining polysilicon layer situated above the oxidation barrier layer, in order to change the work function of the gate composed of polysilicon. The implantation of the germanium ions initially produces an amorphous silicon layer, which is converted into a polycrystalline silicon-germanium compound by subsequent heat treatment or annealing at above 1000° C. in a furnace. The germanium-doped polysilicon layer 4 forms the gate terminal of the MOS transistor, the threshold voltage UT, at which an inversion layer forms in thesubstrate 1, being set by the percentage proportion of germanium in the polysilicon. - FIG. 2 shows a PMOS transistor having a gate terminal G, a source terminal S, and a drain terminal D and whose threshold voltage UT is set by the implantation of germanium ions in the gate. The PMOS transistor has an n-doped
semiconductor substrate 1, with a p+-dopeddrain region 5 and a p+-dopedsource region 6. Electrical contact is made with thedrain region 5 and thesource region 6 respectively viaterminals 7, 8 composed of polysilicon. Moreover, thesemiconductor substrate 1 is covered withfield oxide 9. - The method according to the invention for setting the threshold voltage of a MOS transistor is suitable in particular for setting the threshold voltage UT of MOS transistors in a CMOS fabrication method.
- FIG. 3 shows a CMOS circuit having a PMOS transistor and an NMOS transistor complementary thereto. The NMOS transistor has a
gate 10 which is composed of polysilicon and is isolated from a p-dopedwell region 12 by a dielectric 11. The p-dopedwell 12 is situated in the n-dopedsemiconductor substrate 1. The NMOS transistor has an n+-dopeddrain region 13 and an n+-dopedsource region 14. Electrical contact can be made with thedrain region 13 and thesource region 14 respectively viapolysilicon terminals - By local implantation of germanium ions in the gate3 of the PMOS transistor of the CMOS circuit illustrated in FIG. 3, the threshold voltage UTP of the PMOS transistor can be made the same as the threshold voltage UTN of the NMOS transistor. The higher the concentration of the implanted germanium, the more is the threshold voltage UTP for forming the inversion current channel in the PMOS transistor reduced. The threshold voltage UTN of the NMOS transistor is achieved, as in the conventional fabrication methods, by n+-doping of the
gate 10 composed of polysilicon. The implantation of germanium ions into the polysilicon layer is effected only in the region of the PMOS transistor and not in the region of the NMOS transistor. This is achieved using a resist mask or hard mask which locally covers the polysilicon layer for forming the gate terminals in the region of the NMOS transistor during the implantation of germanium ions. In this case, the masking prevents germanium ions from penetrating into thegate region 10—composed of polysilicon—of the subsequent NMOS transistor. A p+-doping of the gate terminal in the PMOS transistor for the purpose of matching the threshold voltage UTP to the threshold voltage UTN of the NMOS transistor need not be effected since the threshold voltage UTP of the PMOS transistor is effected by the implantation of germanium ions. As a result, the fabrication of the CMOS circuit is simplified overall. - A high concentration of germanium ions in the SiGe gate4 at the interface with the
underlying dielectric 2 leads to a major influence on the work function and thus to a major change in the threshold voltage. The doping concentration of the germanium ions and thus the threshold voltage UT can be set very accurately through the use of the ion implantation. Moreover, concentration profiles can be controlled to the greatest possible extent according to form and position by varying the energy and direction of incidence of the implanted germanium ions. At the same time, the process temperatures can be kept low enough to preclude indiffusion of damaging contaminants. The structural changes caused by the ion implantation in the semiconductor crystal can be compensated by subsequent annealing by thermal treatment. - The method according to the invention improves the short-channel properties of the PMOS transistor without having to change the fabrication method for the NMOS transistor. In this case, the
gate 10—composed of polysilicon—of the NMOS transistor and the silicon gate 4—implanted with germanium ions—of the PMOS transistor are fabricated in a deposition and etching process, as a result of which the fabrication process of a CMOS structure is considerably simplified. - A two-stage polysilicon deposition with germanium implantation with subsequent annealing can be carried out after each deposition. In this case, the implantation with germanium ions after the second deposition simultaneously destroys the silicon oxide which has formed between the deposition processes. A two-stage polysilicon deposition with implantation of germanium ions and subsequent annealing leads to an improvement of germanium depletion effects at the gate/gate oxide interface. The implantation of nitrogen ions for forming an oxidation barrier layer prevents the formation of a germanium oxide layer on the gate oxide surface. This can also be achieved by implanting halogen ions.
Claims (15)
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DE10014916.2 | 2000-03-17 | ||
DE10014916A DE10014916C2 (en) | 2000-03-17 | 2000-03-17 | Method for setting the threshold voltage of a MOS transistor |
DE10014916 | 2000-03-17 |
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US20010023116A1 true US20010023116A1 (en) | 2001-09-20 |
US6451676B2 US6451676B2 (en) | 2002-09-17 |
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US09/811,799 Expired - Lifetime US6451676B2 (en) | 2000-03-17 | 2001-03-19 | Method for setting the threshold voltage of a MOS transistor |
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US (1) | US6451676B2 (en) |
EP (1) | EP1134795B1 (en) |
DE (2) | DE10014916C2 (en) |
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050095773A1 (en) * | 2003-11-05 | 2005-05-05 | Chartered Semiconductor Manufacturing Ltd. | Method to lower work function of gate electrode through Ge implantation |
US20050280095A1 (en) * | 2004-06-16 | 2005-12-22 | Renesas Technology Corp. | Semiconductor device and manufacturing method thereof |
US20220102500A1 (en) * | 2020-09-25 | 2022-03-31 | Applied Materials, Inc. | Localized Stressor Formation By Ion Implantation |
Families Citing this family (8)
Publication number | Priority date | Publication date | Assignee | Title |
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JP2001358233A (en) * | 2000-06-15 | 2001-12-26 | Hitachi Ltd | Semiconductor integrated circuit device and its manufacturing method |
KR100402381B1 (en) * | 2001-02-09 | 2003-10-17 | 삼성전자주식회사 | Cmos transistor having germanium-contained policrystalline silicon gate and method of forming the same |
US6867101B1 (en) * | 2001-04-04 | 2005-03-15 | Advanced Micro Devices, Inc. | Method of fabricating a semiconductor device having a nitride/high-k/nitride gate dielectric stack by atomic layer deposition (ALD) and a device thereby formed |
US6709912B1 (en) * | 2002-10-08 | 2004-03-23 | Chartered Semiconductor Manufacturing Ltd. | Dual Si-Ge polysilicon gate with different Ge concentrations for CMOS device optimization |
US7772063B2 (en) * | 2004-08-11 | 2010-08-10 | Identifi Technologies, Inc. | Reduced-step CMOS processes for low-cost radio frequency identification devices |
US20060172480A1 (en) * | 2005-02-03 | 2006-08-03 | Taiwan Semiconductor Manufacturing Company, Ltd. | Single metal gate CMOS device design |
US9219078B2 (en) | 2013-04-18 | 2015-12-22 | International Business Machines Corporation | Simplified multi-threshold voltage scheme for fully depleted SOI MOSFETs |
US9812449B2 (en) | 2015-11-20 | 2017-11-07 | Samsung Electronics Co., Ltd. | Multi-VT gate stack for III-V nanosheet devices with reduced parasitic capacitance |
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US5426069A (en) | 1992-04-09 | 1995-06-20 | Dalsa Inc. | Method for making silicon-germanium devices using germanium implantation |
US5374566A (en) * | 1993-01-27 | 1994-12-20 | National Semiconductor Corporation | Method of fabricating a BiCMOS structure |
US5633177A (en) | 1993-11-08 | 1997-05-27 | Advanced Micro Devices, Inc. | Method for producing a semiconductor gate conductor having an impurity migration barrier |
JPH07335870A (en) * | 1994-06-14 | 1995-12-22 | Mitsubishi Electric Corp | Semiconductor device and its manufacturing method |
US5675176A (en) * | 1994-09-16 | 1997-10-07 | Kabushiki Kaisha Toshiba | Semiconductor device and a method for manufacturing the same |
EP0707346A1 (en) | 1994-10-11 | 1996-04-17 | Advanced Micro Devices, Inc. | Method for fabricating an integrated circuit |
US5879996A (en) * | 1996-09-18 | 1999-03-09 | Micron Technology, Inc. | Silicon-germanium devices for CMOS formed by ion implantation and solid phase epitaxial regrowth |
US5888867A (en) * | 1998-02-13 | 1999-03-30 | Advanced Micro Devices, Inc. | Non-uniform threshold voltage adjustment in flash eproms through gate work function alteration |
US6208004B1 (en) * | 1998-08-19 | 2001-03-27 | Philips Semiconductor, Inc. | Semiconductor device with high-temperature-stable gate electrode for sub-micron applications and fabrication thereof |
US6180499B1 (en) * | 1998-09-29 | 2001-01-30 | Advanced Micro Devices, Inc. | Method for forming polysilicon-germanium gate in CMOS transistor and device made thereby |
US6114206A (en) * | 1998-11-06 | 2000-09-05 | Advanced Micro Devices, Inc. | Multiple threshold voltage transistor implemented by a damascene process |
-
2000
- 2000-03-17 DE DE10014916A patent/DE10014916C2/en not_active Expired - Fee Related
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2001
- 2001-03-19 EP EP01106383A patent/EP1134795B1/en not_active Expired - Lifetime
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- 2001-03-19 US US09/811,799 patent/US6451676B2/en not_active Expired - Lifetime
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Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050095773A1 (en) * | 2003-11-05 | 2005-05-05 | Chartered Semiconductor Manufacturing Ltd. | Method to lower work function of gate electrode through Ge implantation |
US7101746B2 (en) * | 2003-11-05 | 2006-09-05 | Chartered Semiconductor Manufacturing Ltd. | Method to lower work function of gate electrode through Ge implantation |
US20050280095A1 (en) * | 2004-06-16 | 2005-12-22 | Renesas Technology Corp. | Semiconductor device and manufacturing method thereof |
US7202539B2 (en) * | 2004-06-16 | 2007-04-10 | Renesas Technology Corporation | Semiconductor device having misfet gate electrodes with and without GE or impurity and manufacturing method thereof |
US20220102500A1 (en) * | 2020-09-25 | 2022-03-31 | Applied Materials, Inc. | Localized Stressor Formation By Ion Implantation |
US11728383B2 (en) * | 2020-09-25 | 2023-08-15 | Applied Materials, Inc. | Localized stressor formation by ion implantation |
Also Published As
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US6451676B2 (en) | 2002-09-17 |
TW501204B (en) | 2002-09-01 |
DE50100425D1 (en) | 2003-09-04 |
EP1134795B1 (en) | 2003-07-30 |
DE10014916C2 (en) | 2002-01-24 |
EP1134795A1 (en) | 2001-09-19 |
DE10014916A1 (en) | 2001-10-04 |
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