US20020047171A1 - Low resistance self aligned extended gate structure utilizing a T or Y shaped gate structure for high performance deep submicron FET - Google Patents

Low resistance self aligned extended gate structure utilizing a T or Y shaped gate structure for high performance deep submicron FET Download PDF

Info

Publication number
US20020047171A1
US20020047171A1 US09/978,227 US97822701A US2002047171A1 US 20020047171 A1 US20020047171 A1 US 20020047171A1 US 97822701 A US97822701 A US 97822701A US 2002047171 A1 US2002047171 A1 US 2002047171A1
Authority
US
United States
Prior art keywords
poly
electrode
gate
oxide
layer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US09/978,227
Inventor
Chih-Chung Chiu
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Taiwan Semiconductor Manufacturing Co TSMC Ltd
Original Assignee
Taiwan Semiconductor Manufacturing Co TSMC Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Taiwan Semiconductor Manufacturing Co TSMC Ltd filed Critical Taiwan Semiconductor Manufacturing Co TSMC Ltd
Priority to US09/978,227 priority Critical patent/US20020047171A1/en
Publication of US20020047171A1 publication Critical patent/US20020047171A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/66Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/66007Multistep manufacturing processes
    • H01L29/66075Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials
    • H01L29/66227Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials the devices being controllable only by the electric current supplied or the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched, e.g. three-terminal devices
    • H01L29/66409Unipolar field-effect transistors
    • H01L29/66477Unipolar field-effect transistors with an insulated gate, i.e. MISFET
    • H01L29/665Unipolar field-effect transistors with an insulated gate, i.e. MISFET using self aligned silicidation, i.e. salicide
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/28Manufacture of electrodes on semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/268
    • H01L21/28008Making conductor-insulator-semiconductor electrodes
    • H01L21/28017Making conductor-insulator-semiconductor electrodes the insulator being formed after the semiconductor body, the semiconductor being silicon
    • H01L21/28026Making conductor-insulator-semiconductor electrodes the insulator being formed after the semiconductor body, the semiconductor being silicon characterised by the conductor
    • H01L21/28114Making conductor-insulator-semiconductor electrodes the insulator being formed after the semiconductor body, the semiconductor being silicon characterised by the conductor characterised by the sectional shape, e.g. T, inverted-T
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/66Types of semiconductor device ; Multistep manufacturing processes therefor
    • H01L29/66007Multistep manufacturing processes
    • H01L29/66075Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials
    • H01L29/66227Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials the devices being controllable only by the electric current supplied or the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched, e.g. three-terminal devices
    • H01L29/66409Unipolar field-effect transistors
    • H01L29/66477Unipolar field-effect transistors with an insulated gate, i.e. MISFET
    • H01L29/66545Unipolar field-effect transistors with an insulated gate, i.e. MISFET using a dummy, i.e. replacement gate in a process wherein at least a part of the final gate is self aligned to the dummy gate
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/28Manufacture of electrodes on semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/268
    • H01L21/28008Making conductor-insulator-semiconductor electrodes
    • H01L21/28017Making conductor-insulator-semiconductor electrodes the insulator being formed after the semiconductor body, the semiconductor being silicon
    • H01L21/28026Making conductor-insulator-semiconductor electrodes the insulator being formed after the semiconductor body, the semiconductor being silicon characterised by the conductor
    • H01L21/28035Making conductor-insulator-semiconductor electrodes the insulator being formed after the semiconductor body, the semiconductor being silicon characterised by the conductor the final conductor layer next to the insulator being silicon, e.g. polysilicon, with or without impurities
    • H01L21/28044Making conductor-insulator-semiconductor electrodes the insulator being formed after the semiconductor body, the semiconductor being silicon characterised by the conductor the final conductor layer next to the insulator being silicon, e.g. polysilicon, with or without impurities the conductor comprising at least another non-silicon conductive layer
    • H01L21/28052Making conductor-insulator-semiconductor electrodes the insulator being formed after the semiconductor body, the semiconductor being silicon characterised by the conductor the final conductor layer next to the insulator being silicon, e.g. polysilicon, with or without impurities the conductor comprising at least another non-silicon conductive layer the conductor comprising a silicide layer formed by the silicidation reaction of silicon with a metal layer
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/31Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
    • H01L21/3105After-treatment
    • H01L21/311Etching the insulating layers by chemical or physical means
    • H01L21/31105Etching inorganic layers
    • H01L21/31111Etching inorganic layers by chemical means
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/40Electrodes ; Multistep manufacturing processes therefor
    • H01L29/41Electrodes ; Multistep manufacturing processes therefor characterised by their shape, relative sizes or dispositions
    • H01L29/423Electrodes ; Multistep manufacturing processes therefor characterised by their shape, relative sizes or dispositions not carrying the current to be rectified, amplified or switched
    • H01L29/42312Gate electrodes for field effect devices
    • H01L29/42316Gate electrodes for field effect devices for field-effect transistors
    • H01L29/4232Gate electrodes for field effect devices for field-effect transistors with insulated gate
    • H01L29/42372Gate electrodes for field effect devices for field-effect transistors with insulated gate characterised by the conducting layer, e.g. the length, the sectional shape or the lay-out
    • H01L29/42376Gate electrodes for field effect devices for field-effect transistors with insulated gate characterised by the conducting layer, e.g. the length, the sectional shape or the lay-out characterised by the length or the sectional shape
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L29/00Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
    • H01L29/40Electrodes ; Multistep manufacturing processes therefor
    • H01L29/43Electrodes ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
    • H01L29/49Metal-insulator-semiconductor electrodes, e.g. gates of MOSFET
    • H01L29/4916Metal-insulator-semiconductor electrodes, e.g. gates of MOSFET the conductor material next to the insulator being a silicon layer, e.g. polysilicon doped with boron, phosphorus or nitrogen
    • H01L29/4925Metal-insulator-semiconductor electrodes, e.g. gates of MOSFET the conductor material next to the insulator being a silicon layer, e.g. polysilicon doped with boron, phosphorus or nitrogen with a multiple layer structure, e.g. several silicon layers with different crystal structure or grain arrangement
    • H01L29/4933Metal-insulator-semiconductor electrodes, e.g. gates of MOSFET the conductor material next to the insulator being a silicon layer, e.g. polysilicon doped with boron, phosphorus or nitrogen with a multiple layer structure, e.g. several silicon layers with different crystal structure or grain arrangement with a silicide layer contacting the silicon layer, e.g. Polycide gate

Definitions

  • the present invention relates generally to fabrication of semiconductor devices and more particularly to a structure and a process which results in a field effect transistor (FET) semiconductor device salicided T shaped or alternatively, a Y shaped gate structure with reduced parasitic resistance and capacitance, and improved high speed performance.
  • FET field effect transistor
  • Gate structure sheet resistance is a contributing factor to cutoff frequency (f t ), gate parasitic resistance, gate delay time (charging constant), and maximum frequency performance. (f max ).
  • cutoff frequency f t
  • gate parasitic resistance gate delay time (charging constant)
  • maximum frequency performance f max
  • a T or Y shaped gate structure has the advantage of maintaining or increasing the area of the gate conductor without increasing the essential channel length.
  • the increased area of a salicided T or Y gate structure will improve the effective sheet resistance of the gate electrode structure over a conventional gate structure, and may even reduce the effective resistance with decreasing gate length for certain salicides such as Co salicide.
  • Metal T shaped gate electrode structures have been utilized in the art, but the manufacturing processes can be expensive, unduly complex, and not as compatible with Si ULSI processes as desired.
  • U.S. Pat. No. 5,053,849 issued to Izwa et al. shows an overlapping gate/drain two layer gate structure
  • U.S. Pat. No. 5,559,049 issued to Cho shows a T-gate structure with a single poly layer and capacitively coupled auxiliary side gates
  • U.S. Pat. No. 5,856,232 describes a T-gate made of contact metal, as does U.S. Pat. No. 5,288,660 issued to Hua et al.
  • two alternate gate electrode structures are developed with expanded top portions of the gate electrode to alleviate salicide agglomeration thereby maintaining or reducing electrode resistance improving high frequency performance and reducing gate delay in submicron FET ULSI devices.
  • the method for producing these structures is presented.
  • the top surface of the expanded portion of the electrode has an essentially flat surface such as would be represented in a T shaped gate element.
  • the top surface of the expanded portion of the electrode is inclined upward from near the center of the electrode. This surface angulation results in a Y shaped gate electrode element.
  • Both structures alleviate salicide agglomeration effectively maintaining or reducing electrode sheet resistance without increasing the underlying active channel length.
  • the process is compatible with the self aligned gate process and is also compatible with salicidation methods. It provides the conventional LDD source drain regions as well as the vertical oxide gate electrode sidewall spacers.
  • FIG. 1 shows a cross section through a partially manufactured semiconductor device showing a patterned polysilicon FET gate over gate oxide and initial source drain implantation.
  • FIG. 2 shows the same polysilicon gate structure with the addition of tetraethylorthosilicate (TEOS) poly sidewall spacer and the LDD and main S/D dopant regions.
  • TEOS tetraethylorthosilicate
  • FIG. 3 shows a non-planarized layer of low temperature oxide (LTO) covering the structure.
  • LTO low temperature oxide
  • FIG. 4 shows the LTO after a chemical mechanical polishing (CMP) process.
  • FIG. 5 shows the planarized LTO after a selective buffered oxide etch (BOE) with the top of the poly gate exposed.
  • BOE buffered oxide etch
  • FIG. 6 shows the poly gate recessed with the LTO after a selective wet etch
  • FIG. 7 shows the LTO after an isotropic etch with a depression created around the poly gate.
  • FIG. 8 is the device cross section after a second poly deposition covering the LTO and the original poly vertical gate structure.
  • FIG. 9 shows the device cross section after a CMP planarization of the second poly deposition layer which essentially removes the second poly layer in all areas except the depressed region of the LTO. The remaining second poly effectively form an enlarged top portion of the vertical poly gate electrode or a T shaped electrode.
  • FIG. 10 shows the results of a selectively dry anisotropic etch of the LTO which removes the LTO in all areas except below the enlarged top portion of the poly gate where the remaining LTO forms the poly electrode oxide spacer.
  • FIG. 11 shows a salicide layer covering the top of the poly T gate structure and the top of the source/drain regions.
  • FIG. 12 shows a variation of the invention whereby the CMP planarization step represented in FIG. 9 is eliminated.
  • the remaining process steps with anisotropic dry etching remove second poly and results in a Y shaped gate structure as shown.
  • FIG. 13 is a cross section of the Y gate structure after a selective dry anisotropic etch removed all of the LTO except under the second poly Y top of the gate forming the poly electrode oxide spacer.
  • FIG. 14 is a cross section of the resultant Y gate structure with a covering of salicide over the poly and source drain regions.
  • FIG. 1 there is shown a semiconductor device substrate 10 , typically of monocrystalline silicon.
  • a layer of silicon dioxide (SiO 2 ) 12 is grown over the substrate surface, typically to a thickness of between 20 and 120 Angstroms ( ⁇ ).
  • This is followed by a deposition of polysilicon (poly) 14 to a thickness of between 100 and 300 nm which is appropriately patterned by photolithographic methods to form a vertical poly gate electrode element with an underlying layer of gate oxide 12 .
  • An implant step typically of boron (B) or phosphorus (P) is done to form the basis of the lightly doped source/drain extension (SDD/LDD) 16 .
  • SDD/LDD lightly doped source/drain extension
  • TEOS tetraethylorthosylicide
  • This spacer 20 is used to pattern the source/drain (S/D) heavy dopent implantation which is followed by a rapid thermal annealing (RTA) step to create the S/D regions 18 in the substrate 10 .
  • RTA rapid thermal annealing
  • a low temperature oxide (LTO) 22 layer is deposited over the device surface, typically at a process temperature of between 700 and 800 degrees centigrade (° C.) and to a depth of between 540 and 660 nano meters (nm).
  • FIG. 4 shows a planar LTO surface 22 after a chemical mechanical polishing or planarization (CMP) step.
  • CMP chemical mechanical polishing or planarization
  • the LTO 22 is then selectively etched with a buffered oxide etch (BOE) until the top of the poly gate electrode 14 is exposed as shown in FIG. 5.
  • the BOE solution is typically 1 part hydrofluoric acid (HF), an assay of 49°, 10 parts of ammonium fluoride (NH 4 F), assay of 40%.
  • FIG. 8 shows a second layer of polysilicon 24 being deposited on the structure.
  • the surface of this layer is not planar as it is nominally conformal to the depression 23 in LTO 22 in proximity to the first poly electrode region 14 .
  • FIG. 9 shows the result of CMP process which has removed the second poly layer 24 except in depression area 23 of the LTO surrounding the first poly gate electrode.
  • the second poly essentially forms an extended area cap 24 A on top of the first poly electrode 14 producing an effective T shaped poly gate electrode element.
  • FIG. 10 shows the result of a selective dry anisotropic etch such as obtained from a reactive ion etch (RIE) process which removes the LTO in all regions except directly under the second poly extended cap 24 A.
  • RIE reactive ion etch
  • FIG. 11 shows a salicide layer 26 over the gate poly 24 A and the source drain regions 18 .
  • the salicide is typically formed from the deposition of a refractory metal such as titanium (Ti), tungsten (W), cobalt (Co), or tantalum (Ta).
  • Ti titanium
  • W tungsten
  • Co cobalt
  • Ta tantalum
  • the salicide is formed when the metal is alloyed on a silicon surface to form TiSi 2 , WSi 2 , or TaSi 2 .
  • the salicided T gate structure effectively increases the electrical contact area of the gate electrode and reduces salicide agglomeration thereby maintaining or reducing effective sheet resistance while enabling the narrow gate channel length necessary for small high speed devices required for ULSI.
  • FIG. 12 shows an alternative implementation of the invention.
  • the initial process steps are the same as in the T gate process, up to the second poly 24 deposition.
  • the CMP planarization step is omitted.
  • the second poly layer 24 has a surface depression 23 A shown in FIG. 8 that approximates the depression in the underlying LTO 23 surrounding the first poly 14 gate element.
  • a selective anisotropic dry etch such as a RIE process is applied to the second poly element 24 etching the second poly down to the surface of the LTO layer 22 , and exposing the top surface of the first poly gate electrode 14 .
  • the only remaining part of the second poly is the amount of second poly 24 B that was embedded in the depression 23 in the LTO around the first poly 14 electrode.
  • This element of the second poly 24 B forms an expanded upper section of the poly gate electrode.
  • the top surface of this second poly cap 24 B is angulated from the top of the first poly electrode 14 rising up to the top of the LTO 22 at the periphery. This angulation forms an extended electrode area forming a Y shaped element, which minimizes salicide agglomeration and maintains or reduces the effective sheet resistance of the gate electrode while enabling the narrow gate channel length necessary for small high speed devices required for ULSI.
  • FIG. 13 shows the result of a selective dry anisotropic etch which removes the LTO 22 in all regions except directly under the second poly extended Y electrode top 24 B. This remaining oxide forms the vertical side spacer 22 A for the gate electrode element.
  • FIG. 14 shows a salicide layer 26 over the gate poly 24 B and first poly 14 and the source drain regions 18 .

Landscapes

  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • Ceramic Engineering (AREA)
  • Insulated Gate Type Field-Effect Transistor (AREA)

Abstract

Two alternate gate electrode structures are developed with expanded top portions of the gate electrode to maintain or reduce electrode effective sheer resistance improving high frequency performance and reducing gate delay in submicron FET ULSI devices. The method for producing these structures is presented. For one structure the top surface of the expanded portion of the electrode has an essentially flat surface such as would be represented in a T shaped gate element. With the alternative structure the top surface of the expanded portion of the electrode is inclined upward from near the center of the electrode. This surface angulation results in a Y shaped gate electrode element. Both structures effectively maintain or reduce electrode sheet resistance without increasing the underlying active channel length. The process is compatible with the self aligned gate process and is also compatible with salicidation methods. It provides the conventional LDD source drain regions as well as the vertical oxide gate electrode sidewall spacers.

Description

    BACKGROUND OF THE INVENTION
  • (1) Field of the Invention [0001]
  • The present invention relates generally to fabrication of semiconductor devices and more particularly to a structure and a process which results in a field effect transistor (FET) semiconductor device salicided T shaped or alternatively, a Y shaped gate structure with reduced parasitic resistance and capacitance, and improved high speed performance. [0002]
  • (2) Description of the Prior Art [0003]
  • As field effect transistor (FET) devices are scaled down to have channel lengths in the submicron and deep submicron ranges as required for the device densities of ultra large scale integration (ULSI), gate electrical characteristics can be degraded. This is particularly true for ultra electrode structure with decreasing gate structure size, can degrade device high speed performance. Salilicided structures have been proposed for these ultra small gate elements, but the narrow line width effect causes an increase in the effective sheet resistance of the gate contact element, with salicide agglomeration a contributing factor, as well as creating difficulties with the fabrication process as the technology is scaled down to submicron and deep submicron regions. [0004]
  • When an ultra high speed integrated circuit is designed and fabricated, several high frequency characteristics are important. Gate structure sheet resistance is a contributing factor to cutoff frequency (f[0005] t), gate parasitic resistance, gate delay time (charging constant), and maximum frequency performance. (fmax). In general, as channel length and subsequently gate length is decreased, high speed and high frequency performance is improved. However, the reduction of the gate length for devices in the submicron range causes a salicide agglomeration which usually increases the effective gate conductor sheet resistance, and hence degrades high speed performance characteristics. A T or Y shaped gate structure has the advantage of maintaining or increasing the area of the gate conductor without increasing the essential channel length. The increased area of a salicided T or Y gate structure will improve the effective sheet resistance of the gate electrode structure over a conventional gate structure, and may even reduce the effective resistance with decreasing gate length for certain salicides such as Co salicide. (See “A Novel Self-Aligned T-Shaped Gate Process for Deep Submicron Si FET Fabrication authored by Horng-Chih Lin et al., IEEE Electron Device Letters, Vol. 19, NO. 1 January 1998, pages 26 through 28.)
  • Metal T shaped gate electrode structures have been utilized in the art, but the manufacturing processes can be expensive, unduly complex, and not as compatible with Si ULSI processes as desired. [0006]
  • U.S. Pat. No. 5,053,849 issued to Izwa et al. shows an overlapping gate/drain two layer gate structure, U.S. Pat. No. 5,817,558 issued to Wu describing a T-shaped gate formed of amorphous silicon. U.S. Pat. No. 5,559,049 issued to Cho shows a T-gate structure with a single poly layer and capacitively coupled auxiliary side gates, U.S. Pat. No. 5,856,232 describes a T-gate made of contact metal, as does U.S. Pat. No. 5,288,660 issued to Hua et al. [0007]
  • The following technical reports discuss high performance gate structures. [0008]
  • A Novel Self-Aligned T shaped Gate Process for Deep Submicron Si MOSFET's Fabrication, author(s) Lin et al. IEEE Electron Device Letters, Vol. 19, No. 1, Jan. 1998, pp26 to 28. Sub 100NM Gate length Metal Gate NMOS transistors fabricated by a replacement gate Process by Chatterjee et al., journal not identified. [0009]
  • A High Performance 0.1um CMOS with Elevated Silicide using Novel Si SEG Process by Wakabayahi et al., journal not identified. [0010]
  • A Low Resistance Self Aligned T-Shaped Gate for High Performance Sub.1 Um CMOS by Hisamoto et al., IEEE transactions on Electron Devices, Vol. 44 No. 6. June 1997, pp. 951-956. [0011]
  • SUMMARY OF THE INVENTION
  • Accordingly, it is the primary objective of the invention to provide an effective and manufacturable method for improving FET salicided gate electrode sheet resistance by extending the electrode length without extending the active control length by using a T or Y shaped top portion of the gate electrode. [0012]
  • It is a further objective of this invention to maintain or improve the high frequency characteristics of submicron FET devices as circuit density increases with the advent of ULSI by maintaining or reducing FET gate electrode sheet resistance. [0013]
  • It is also an objective of this invention to utilize a salicide process compatible with ULSI FET processing while at the same time maintaining or improving high frequency performance of the devices. [0014]
  • In accordance with the objects of the invention, two alternate gate electrode structures are developed with expanded top portions of the gate electrode to alleviate salicide agglomeration thereby maintaining or reducing electrode resistance improving high frequency performance and reducing gate delay in submicron FET ULSI devices. The method for producing these structures is presented. For one structure the top surface of the expanded portion of the electrode has an essentially flat surface such as would be represented in a T shaped gate element. With the alternative structure the top surface of the expanded portion of the electrode is inclined upward from near the center of the electrode. This surface angulation results in a Y shaped gate electrode element. Both structures alleviate salicide agglomeration effectively maintaining or reducing electrode sheet resistance without increasing the underlying active channel length. The process is compatible with the self aligned gate process and is also compatible with salicidation methods. It provides the conventional LDD source drain regions as well as the vertical oxide gate electrode sidewall spacers.[0015]
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1 shows a cross section through a partially manufactured semiconductor device showing a patterned polysilicon FET gate over gate oxide and initial source drain implantation. [0016]
  • FIG. 2 shows the same polysilicon gate structure with the addition of tetraethylorthosilicate (TEOS) poly sidewall spacer and the LDD and main S/D dopant regions. [0017]
  • FIG. 3 shows a non-planarized layer of low temperature oxide (LTO) covering the structure. [0018]
  • FIG. 4 shows the LTO after a chemical mechanical polishing (CMP) process. [0019]
  • FIG. 5 shows the planarized LTO after a selective buffered oxide etch (BOE) with the top of the poly gate exposed. [0020]
  • FIG. 6 shows the poly gate recessed with the LTO after a selective wet etch [0021]
  • FIG. 7 shows the LTO after an isotropic etch with a depression created around the poly gate. [0022]
  • FIG. 8 is the device cross section after a second poly deposition covering the LTO and the original poly vertical gate structure. [0023]
  • FIG. 9 shows the device cross section after a CMP planarization of the second poly deposition layer which essentially removes the second poly layer in all areas except the depressed region of the LTO. The remaining second poly effectively form an enlarged top portion of the vertical poly gate electrode or a T shaped electrode. [0024]
  • FIG. 10 shows the results of a selectively dry anisotropic etch of the LTO which removes the LTO in all areas except below the enlarged top portion of the poly gate where the remaining LTO forms the poly electrode oxide spacer. [0025]
  • FIG. 11 shows a salicide layer covering the top of the poly T gate structure and the top of the source/drain regions. [0026]
  • FIG. 12 shows a variation of the invention whereby the CMP planarization step represented in FIG. 9 is eliminated. The remaining process steps with anisotropic dry etching remove second poly and results in a Y shaped gate structure as shown. [0027]
  • FIG. 13 is a cross section of the Y gate structure after a selective dry anisotropic etch removed all of the LTO except under the second poly Y top of the gate forming the poly electrode oxide spacer. [0028]
  • FIG. 14 is a cross section of the resultant Y gate structure with a covering of salicide over the poly and source drain regions.[0029]
  • DESCRIPTION OF THE PREFERRED EMBODIMENTS
  • Referring to FIG. 1 there is shown a [0030] semiconductor device substrate 10, typically of monocrystalline silicon. A layer of silicon dioxide (SiO2) 12 is grown over the substrate surface, typically to a thickness of between 20 and 120 Angstroms (Å). This is followed by a deposition of polysilicon (poly) 14 to a thickness of between 100 and 300 nm which is appropriately patterned by photolithographic methods to form a vertical poly gate electrode element with an underlying layer of gate oxide 12. An implant step, typically of boron (B) or phosphorus (P) is done to form the basis of the lightly doped source/drain extension (SDD/LDD) 16.
  • Referring to FIG. 2, tetraethylorthosylicide (TEOS) has been deposited, patterned and anisotropically etched to form a [0031] spacer 20 surrounding the vertical poly gate electrode 14. This spacer 20 is used to pattern the source/drain (S/D) heavy dopent implantation which is followed by a rapid thermal annealing (RTA) step to create the S/D regions 18 in the substrate 10. As depicted in FIG. 3, a low temperature oxide (LTO) 22 layer is deposited over the device surface, typically at a process temperature of between 700 and 800 degrees centigrade (° C.) and to a depth of between 540 and 660 nano meters (nm). The poly gate electrode topology results in a non planar surface for the LTO 22, in particular over the first poly electrode 14. FIG. 4 shows a planar LTO surface 22 after a chemical mechanical polishing or planarization (CMP) step. The LTO 22 is then selectively etched with a buffered oxide etch (BOE) until the top of the poly gate electrode 14 is exposed as shown in FIG. 5. The BOE solution is typically 1 part hydrofluoric acid (HF), an assay of 49°, 10 parts of ammonium fluoride (NH4F), assay of 40%. There follows a selective poly gate wet etch, typically a solution of nitric, hydrofluoric and acetic acids mixed with water, which reduces the poly electrode 14 height recessing it within the surrounding LTO 22 as shown in FIG. 6. There follows a second BOE isotropic etch using the same formulation as the first etch, which results in a depression 23 in the LTO in the region surrounding the poly gate electrode 14 as shown in FIG. 7.
  • FIG. 8 shows a second layer of [0032] polysilicon 24 being deposited on the structure. The surface of this layer is not planar as it is nominally conformal to the depression 23 in LTO 22 in proximity to the first poly electrode region 14. FIG. 9 shows the result of CMP process which has removed the second poly layer 24 except in depression area 23 of the LTO surrounding the first poly gate electrode. The second poly essentially forms an extended area cap 24A on top of the first poly electrode 14 producing an effective T shaped poly gate electrode element.
  • FIG. 10 shows the result of a selective dry anisotropic etch such as obtained from a reactive ion etch (RIE) process which removes the LTO in all regions except directly under the second poly extended [0033] cap 24A. The process selectivity minimizes any etching of the poly cap. This remaining oxide forms the vertical side spacer 22A for the gate electrode element.
  • FIG. 11 shows a [0034] salicide layer 26 over the gate poly 24A and the source drain regions 18. The salicide is typically formed from the deposition of a refractory metal such as titanium (Ti), tungsten (W), cobalt (Co), or tantalum (Ta). The salicide is formed when the metal is alloyed on a silicon surface to form TiSi2, WSi2, or TaSi2. The salicided T gate structure effectively increases the electrical contact area of the gate electrode and reduces salicide agglomeration thereby maintaining or reducing effective sheet resistance while enabling the narrow gate channel length necessary for small high speed devices required for ULSI.
  • FIG. 12 shows an alternative implementation of the invention. The initial process steps are the same as in the T gate process, up to the [0035] second poly 24 deposition. After the second poly deposition 24 shown in FIG. 8, the CMP planarization step is omitted. The second poly layer 24 has a surface depression 23A shown in FIG. 8 that approximates the depression in the underlying LTO 23 surrounding the first poly 14 gate element. A selective anisotropic dry etch such as a RIE process is applied to the second poly element 24 etching the second poly down to the surface of the LTO layer 22, and exposing the top surface of the first poly gate electrode 14. The only remaining part of the second poly is the amount of second poly 24B that was embedded in the depression 23 in the LTO around the first poly 14 electrode. This element of the second poly 24B forms an expanded upper section of the poly gate electrode. The top surface of this second poly cap 24B is angulated from the top of the first poly electrode 14 rising up to the top of the LTO 22 at the periphery. This angulation forms an extended electrode area forming a Y shaped element, which minimizes salicide agglomeration and maintains or reduces the effective sheet resistance of the gate electrode while enabling the narrow gate channel length necessary for small high speed devices required for ULSI.
  • FIG. 13 shows the result of a selective dry anisotropic etch which removes the [0036] LTO 22 in all regions except directly under the second poly extended Y electrode top 24B. This remaining oxide forms the vertical side spacer 22A for the gate electrode element.
  • FIG. 14 shows a [0037] salicide layer 26 over the gate poly 24B and first poly 14 and the source drain regions 18.
  • While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the invention.[0038]

Claims (29)

What is claimed is:
1. A FET self aligned gate (SAG) structure with an extended polysilicon and salicide electrode structure which maintains or decreases the effective sheet resistance of the electrode as the active gate control width and resulting channel length is decreased into the sub micron region comprising
a gate oxide layer insulating said gate electrode from said channel
a first layer of polysilicon as the primary vertical electrode element of said gate
a source/drain dopant implant
an oxide formed to provide said gate electrode vertical spacer insulator.
2. The structure of claim 1 whereby a second polysilicon layer is connected to the top of said vertical first polysilicon gate electrode and on top of said oxide spacer, the top surface of said second poly is planarized effectively forming a T shaped top for said vertical electrode and said top of said second poly layer is covered with a salicide to further improve effective gate sheet resistance.
3. The structure of claim 1 whereby a second polysilicon layer is connected to the top of said vertical first polysilicon gate electrode and the top surface of said poly is anisotropically etched to effectively form a Y shaped top for said vertical electrode and said top of said second poly layer is covered with a salicide to further improve effective sheet resistance.
4. A FET (SAG) structure with an extended polysilicon and salicide electrode structure in the form of a T which maintains or decreases the effective sheet resistance of the electrode as the active gate control width and resulting channel length is decreased into the sub micron region comprising
a gate oxide layer insulating said gate electrode from said channel
a first layer of polysilicon as the primary vertical electrode element of said gate
a source/drain dopant implant
an oxide formed to provide said gate electrode vertical spacer insulator.
5. The structure in claim 4 whereby a second layer of polysilicon is connected to the top of said vertical first poly electrode element extending over said oxide spacer and the top surface of said second poly layer is planarized to effectively form said T shaped top for said gate electrode.
6. The structure of claim 4 whereby said top of said second poly is covered with a salicide to further improve effectively sheet resistance.
7. A FET (SAG) structure with an extended polysilicon and salicide electrode structure in the form of a Y which maintains or decreases the effective sheet resistance of the electrode as the active gate control width and resulting channel length is decreased into the sub micron region comprising
a gate oxide layer insulating said gate electrode from said channel
a first layer of polysilicon as the primary vertical electrode element of said gate
a source/drain dopant implant
an oxide formed to provide said gate electrode vertical spacer insulator.
8. The structure in claim 7 whereby a second layer of polysilicon is connected to the top of said vertical first poly electrode element extending over said oxide spacer and the top surface of said second poly layer is anisotropically etched to effectively form said Y shaped top for said gate electrode.
9. The structure of claim 4 whereby said top of second poly is covered with a salicide to further improve effective sheet resistance.
10. A method and novel process for forming a low resistance self aligned salicided T-shaped FET gate structure compatible with ULSI semiconductor processing comprising:
forming a gate oxide layer on a substrate active area, patterning a first polysilicon layer gate electrode and implanting a dopant as the basis of the S/D lightly doped extensions:
forming an oxide spacer on the vertical sides of said poly gate electrode and implanting the deep region dopant of said S/D region
depositing an oxide layer over said poly electrode and said active device surface,
planarizing said oxide covered structure and selectively etching said oxide surface to expose top of said first poly gate electrode:
selectively etching said first poly electrode to recess it within said covering oxide;
isotropically etching said covering oxide to open a depression in said oxide around the top of said first poly electrode:
depositing and planarizing a second layer of polysilicon over said active device area so that second poly remains only in said depression on top of said first poly electrode and within said oxide covering layer forming a T shaped top of said electrode;
selectively dry etching said covering oxide layer with said oxide remaining on the vertical side of said first poly electrode between said active device surface and said second poly T shaped element forming said gate spacer oxide isolation:
forming salicide over said top surfaces of said second poly T shaped element and said device active area.
11. The method according to claim 10 wherein said covering oxide in low temperature oxide formed at a temperature of between 700 and 800 degrees C. (° C.) to a depth of between 540 and 660 nano meters (nm).
12. The method according to claim 10 whereby the planarization is performed by chemical mechanical polishing (CMP) methods which reduces the LTO thickness to between 360 and 440 nm.
13. The method according to claim 10 whereby the selective LTO etching is done using a buffered oxide etch containing 1 part of 49% HF and 10 parts of 40% NH4F which etches said LTO to a thickness between 270 and 300 nm effectively exposing the top of said first poly vertical gate element.
14. The method according to claim 10 whereby the selective etch of said first poly electrode is done by a wet etch to reduce said first poly to a height between 135 and 165 nm, recessing said electrode within said LTO.
15. The method according to claim 10 whereby the isotropic second etch of the LTO is done with a BOE solution with a concentration of HF and NH4F elements in a concentration of 1:10 to reduce the LTO to a thickness of between 180 and 220 nm, effectively creating a recess in said LTO around the top of said first poly gate element.
16. The method according to claim 10 whereby second poly deposition is deposited to a thickness of between 180 and 220 nm at a temperature between 520 and 640° C.
17. The method according to claim 10 whereby said second poly is planarized by a CMP down to the planar surface of said LTO leaving said second poly only in said recess in LTO around said top of said first poly gate element.
18. The method according to claim 10 whereby said LTO is selectively anisotropically dry etched by a RIE process with said oxide only remaining on said vertical side of said first poly electrode between said active device area and said second poly T shaped element forming said gate spacer oxide isolation.
19. The method according to claim 10 whereby a salicide of Titanium or Cobalt is formed over said top surface of said T gate electrode structure and the top surface of said source drain regions.
20. A method and novel process for forming a low resistance self aligned salicided Y-shaped FET gate structure compatible with ULSI semiconductor processes comprising:
forming a gate oxide layer on a substrate active area, patterning a first polysilicon layer gate electrode and implanting a dopant as the basis of the S/D lightly doped extensions:
forming a gate oxide layer on a substrate active area, patterning a first polysilicon layer gate electrode and implanting a dopant as the basis of the S/D lightly doped extensions;
forming an oxide spacer on the vertical sides of said poly gate electrode and implanting the deep region dopant of said S/D region
depositing a covering oxide layer over said poly electrode and said active device surface,
planarizing said oxide covered structure and selectively etching said oxide surface to expose top of said first poly gate electrode;
selectively etching said first poly electrode to recess it within said covering oxide;
isotropically etching said covering oxide to open a depression in said covering oxide around the top of said first poly electrode;
depositing a second layer of polysilicon over said covering oxide
selectively dry etching said second poly so that said second poly only remains in said depression in said covering oxide around said first poly electrode forming a Y shaped gate electrode element,
selectively dry etching said covering oxide layer to form a vertical structure with said oxide remaining on the vertical side of first poly electrode between said active device surface and said second poly Y shaped element forming gate spacer oxide isolation;
forming salicide over top surface of said second poly Y shaped element and device active area.
21. The method according to claim 20 wherein said oxide covering is low temperature oxide formed at a temperature of between 700 and 800° C. to a depth of between 540 and 660 nm.
22. The method according to claim 20 whereby the planarization is performed by chemical mechanical polishing (CMP) methods which reduces the LTO thickness to between 360 and 440 nm.
23. The method according to claim 20 whereby the selective LTO etching is done using a buffered oxide etch solution containing 1 part of 49% HF and 10 parts of 40% NH4F which etches said LTO to a thickness between 270 and 300 nm effectively exposing the top of said first poly vertical gate element.
24. The method according to claim 20 whereby the selective etch of said first poly electrode is done by a wet etch to reduce said first poly to a height between 135 and 165 nm, recessing said electrode within said LTO.
25. The method according to claim 20 whereby the isotropic second etch of the LTO is done with a BOE solution containing 1 part of 49% HF and 10 parts of 40%NH4F which etches said LTO to a thickness between 180 and 220 nm, effectively creating a recess in said LTO around said top of said first poly gate element.
26. The method according to claim 20 whereby said second poly is deposited to a thickness of between 180 and 220 nm at a temperature between 520 and 660° C.
27. The method according to claim 20 whereby said second poly is selectively dry etched to the top of said first poly electrode forming a second poly spacer around said first poly electrode forming a Y shaped electrode structure.
28. The method according to claim 20 whereby said LTO is selectively anisotropically dry etched by a RIE process with said oxide only remaining on said vertical side of said first poly electrode between said active device area and said second poly Y shaped element forming said gate spacer oxide isolation.
29. The method according to claim 20 whereby a salicide of Titanium or Cobalt is formed over said top surface of said Y gate electrode structure and the top surface of said source drain regions.
US09/978,227 2000-03-21 2001-10-16 Low resistance self aligned extended gate structure utilizing a T or Y shaped gate structure for high performance deep submicron FET Abandoned US20020047171A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US09/978,227 US20020047171A1 (en) 2000-03-21 2001-10-16 Low resistance self aligned extended gate structure utilizing a T or Y shaped gate structure for high performance deep submicron FET

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US09/531,782 US6326290B1 (en) 2000-03-21 2000-03-21 Low resistance self aligned extended gate structure utilizing A T or Y shaped gate structure for high performance deep submicron FET
US09/978,227 US20020047171A1 (en) 2000-03-21 2001-10-16 Low resistance self aligned extended gate structure utilizing a T or Y shaped gate structure for high performance deep submicron FET

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US09/531,782 Division US6326290B1 (en) 2000-03-21 2000-03-21 Low resistance self aligned extended gate structure utilizing A T or Y shaped gate structure for high performance deep submicron FET

Publications (1)

Publication Number Publication Date
US20020047171A1 true US20020047171A1 (en) 2002-04-25

Family

ID=24119019

Family Applications (2)

Application Number Title Priority Date Filing Date
US09/531,782 Expired - Lifetime US6326290B1 (en) 2000-03-21 2000-03-21 Low resistance self aligned extended gate structure utilizing A T or Y shaped gate structure for high performance deep submicron FET
US09/978,227 Abandoned US20020047171A1 (en) 2000-03-21 2001-10-16 Low resistance self aligned extended gate structure utilizing a T or Y shaped gate structure for high performance deep submicron FET

Family Applications Before (1)

Application Number Title Priority Date Filing Date
US09/531,782 Expired - Lifetime US6326290B1 (en) 2000-03-21 2000-03-21 Low resistance self aligned extended gate structure utilizing A T or Y shaped gate structure for high performance deep submicron FET

Country Status (1)

Country Link
US (2) US6326290B1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060108650A1 (en) * 2003-02-28 2006-05-25 Chan-Hyung Cho Method of enlarging contact area of a gate electrode, semiconductor device having a surface-enlarged gate electrode, and method of manufacturing the same
US20190228976A1 (en) * 2018-01-22 2019-07-25 Globalfoundries Inc. Capping structure

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6509253B1 (en) * 2001-02-16 2003-01-21 Advanced Micro Devices, Inc. T-shaped gate electrode for reduced resistance
KR100384784B1 (en) 2001-08-07 2003-05-23 주식회사 하이닉스반도체 Method for forming gate of semiconductor device
KR100465055B1 (en) 2001-12-29 2005-01-05 매그나칩 반도체 유한회사 Method of manufacturing a transistor in a semiconductor device
US6780694B2 (en) * 2003-01-08 2004-08-24 International Business Machines Corporation MOS transistor
US20040142517A1 (en) * 2003-01-17 2004-07-22 Chih-Wei Chang Hatted polysilicon gate structure for improving salicide performance and method of forming the same
KR100563095B1 (en) * 2003-09-24 2006-03-27 동부아남반도체 주식회사 Method for fabricating silicide of semiconductor device
CN100376020C (en) * 2003-12-29 2008-03-19 中芯国际集成电路制造(上海)有限公司 A method for manufacturing transistor with extending gate
US7241674B2 (en) * 2004-05-13 2007-07-10 Taiwan Semiconductor Manufacturing Co., Ltd. Method of forming silicided gate structure
US7015126B2 (en) * 2004-06-03 2006-03-21 Taiwan Semiconductor Manufacturing Co., Ltd. Method of forming silicided gate structure
US7396767B2 (en) * 2004-07-16 2008-07-08 Taiwan Semiconductor Manufacturing Co., Ltd. Semiconductor structure including silicide regions and method of making same

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4939071A (en) * 1984-03-06 1990-07-03 Harris Corporation Method for forming low resistance, sub-micrometer semiconductor gate structures
US5053849A (en) * 1987-04-24 1991-10-01 Hitachi, Ltd. Transistor with overlapping gate/drain and two-layered gate structures
US5288660A (en) * 1993-02-01 1994-02-22 Avantek, Inc. Method for forming self-aligned t-shaped transistor electrode
US5559049A (en) * 1994-07-25 1996-09-24 Hyundai Electronics Insustries Co., Ltd Method of manufacturing a semiconductor device
US5585307A (en) * 1995-02-27 1996-12-17 Taiwan Semiconductor Manufacturing Company Ltd. Forming a semi-recessed metal for better EM and Planarization using a silo mask
US5688704A (en) * 1995-11-30 1997-11-18 Lucent Technologies Inc. Integrated circuit fabrication
US5817558A (en) * 1997-06-20 1998-10-06 Acer Semiconductor Manufacturing Inc. Method of forming a T-gate Lightly-Doped Drain semiconductor device
US5856232A (en) * 1995-11-21 1999-01-05 Electronics And Telecommunications Research Institute Method for fabricating T-shaped electrode and metal layer having low resistance

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4829025A (en) * 1987-10-02 1989-05-09 Advanced Micro Devices, Inc. Process for patterning films in manufacture of integrated circuit structures
US5966597A (en) * 1998-01-06 1999-10-12 Altera Corporation Method of forming low resistance gate electrodes
US6069032A (en) * 1999-08-17 2000-05-30 United Silicon Incorporated Salicide process
TW419755B (en) * 1999-12-10 2001-01-21 Taiwan Semiconductor Mfg Manufacturing method of T-shaped gate of integrated circuit

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4939071A (en) * 1984-03-06 1990-07-03 Harris Corporation Method for forming low resistance, sub-micrometer semiconductor gate structures
US5053849A (en) * 1987-04-24 1991-10-01 Hitachi, Ltd. Transistor with overlapping gate/drain and two-layered gate structures
US5288660A (en) * 1993-02-01 1994-02-22 Avantek, Inc. Method for forming self-aligned t-shaped transistor electrode
US5559049A (en) * 1994-07-25 1996-09-24 Hyundai Electronics Insustries Co., Ltd Method of manufacturing a semiconductor device
US5585307A (en) * 1995-02-27 1996-12-17 Taiwan Semiconductor Manufacturing Company Ltd. Forming a semi-recessed metal for better EM and Planarization using a silo mask
US5856232A (en) * 1995-11-21 1999-01-05 Electronics And Telecommunications Research Institute Method for fabricating T-shaped electrode and metal layer having low resistance
US5688704A (en) * 1995-11-30 1997-11-18 Lucent Technologies Inc. Integrated circuit fabrication
US5817558A (en) * 1997-06-20 1998-10-06 Acer Semiconductor Manufacturing Inc. Method of forming a T-gate Lightly-Doped Drain semiconductor device

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060108650A1 (en) * 2003-02-28 2006-05-25 Chan-Hyung Cho Method of enlarging contact area of a gate electrode, semiconductor device having a surface-enlarged gate electrode, and method of manufacturing the same
US20190228976A1 (en) * 2018-01-22 2019-07-25 Globalfoundries Inc. Capping structure
US10559470B2 (en) * 2018-01-22 2020-02-11 Globalfoundries Inc. Capping structure

Also Published As

Publication number Publication date
US6326290B1 (en) 2001-12-04

Similar Documents

Publication Publication Date Title
US7514346B2 (en) Tri-gate devices and methods of fabrication
US6780694B2 (en) MOS transistor
US6974738B2 (en) Nonplanar device with stress incorporation layer and method of fabrication
US7303965B2 (en) MIS transistor and method for producing same
US6472258B1 (en) Double gate trench transistor
US6642115B1 (en) Double-gate FET with planarized surfaces and self-aligned silicides
US20070210357A1 (en) Mosfet having recessed channel and method of fabricating the same
US6326290B1 (en) Low resistance self aligned extended gate structure utilizing A T or Y shaped gate structure for high performance deep submicron FET
US6169017B1 (en) Method to increase contact area
US7012014B2 (en) Recessed gate structure with reduced current leakage and overlap capacitance
US6884669B2 (en) Hatted polysilicon gate structure for improving salicide performance and method of forming the same
JP2000049348A (en) Semiconductor device with elevated source drain structure and its manufacture
US8008141B2 (en) Method of fabricating a semiconductor device with multiple channels
US20090275184A1 (en) Fabricating Method of Semiconductor Device
JP2001237428A (en) Structure of semiconductor electronic device and method of manufacturing the same
JP2002313803A (en) Semiconductor device and its manufacturing method

Legal Events

Date Code Title Description
STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION