International Business Machines Corporation

Other

Siemens Aktiengesellschaft

Infineon Technologies Ag

Mary Elizabeth Weybright

Ramachandra Divakaruni

Jeffrey P Gambino

Carl John Radens

Gary Bela Bronner

Jack Allan Mandelman

Oleg Gluschenkov

Wayne Frederick Ellis

Helmut Horst Tews

Robert C Wong

Richard Anthony Conti

Rama Divakaruni

Stephan Kudelka

Scott David Halle

Rajesh Rengarajan

Uwe Schroeder

Peter D Hoh

William R Tonti

Toshiharu Furukawa

Dureseti Chidambarrao

Geng Wang

James William Adkisson

Viraj Yashawant Sardesai

Edward William Kiewra

Heon Lee

Yujun Li

Dale Warner Martin

Kevin McStay

Thomas S Rupp

Giuseppe La Rosa

Ryota Katsumata

Suri Hegde

Yujun c/o Ibm United Kingdom Ltd Li

A double sidewall image transfer process for forming FinFET structures having a fin pitch of less than 40 nm generates paired fins with a spacing determined by the width of a sidewall spacer that forms a second mandrel. Here, the fin pairs are created at two different spacings without requiring the minimum space for the standard sidewall structure. An enlarged space between paired fins is created by placing two first mandrel shapes close enough so as to overlap or merge two sidewall spacer shapes so as to form a wider second mandrel upon further processing. The fin pair created from the wider second mandrel is spaced at about 2 times the fin pair created from the narrower second mandrel. For some circuits, such as an SRAM bitcell, the wider second mandrel can be utilized to form an inactive fin not utilized in the circuit structure, which can be removed. In some embodiments, all dummy inactive fins are eliminated for a simpler process.

SRAM design to facilitate single fin cut in double sidewall image transfer process

A method of formation of a deep trench vertical transistor is provided. A deep trench with a sidewall in a doped semiconductor substrate is formed. The semiconductor substrate includes a counterdoped drain region in the surface thereof and a channel alongside the sidewall. The drain region has a top level and a bottom level. A counterdoped source region is formed in the substrate juxtaposed with the sidewall below the channel. A gate oxide layer is formed on the sidewalls of the trench juxtaposed with a gate conductor. Perform the step of recessing the gate conductor below the bottom level of the drain region followed by performing angled ion implantation at an angle &#x3b8;+&#x3b4; with respect to vertical of a counterdopant into the channel below the source region and performing angled ion implantation at an angle &#x3b8; with respect to vertical of a dopant into the channel below the source.

Self-aligned drain/channel junction in vertical pass transistor DRAM cell design for device scaling

P-type metal-oxide semiconductor field effect transistor (PMOSFET) devices have a characteristic property known as threshold voltage. This threshold voltage may consist of separate threshold voltages associated with the main portion of the gate region of the device and with the sidewall corner of the device. Under some conditions, the threshold behavior in the sidewall corner region of the device may dominate the performance of the device, not necessarily in the manner intended by the designer of the device. A method of controlling threshold voltage behavior is described. In particular, ion implantation of nitrogen in the gate sidewall region of the device can provide such control. Devices made by this method are also described.

PMOSFET device with localized nitrogen sidewall implantation

A memory device structure including an array device region having one or more asymmetric gates formed therein, wherein each asymmetric gate comprises a first edge having a substantially vertical sidewall and a second edge having a polysilicon step segment, and a support device region including one or more patterned gate conductors formed therein, wherein each patterned gate conductor in the support device region includes edges having substantially vertical sidewalls. The structure may further include a circuit device region located between the array device region and the support device region, said core device region including one or more patterned gates, each gate including a polysilicon step segment on each side of the gate.

Asymmetric gates for high density DRAM

Disclosed is a method of processing a semiconductor gate structure on a semiconductor wafer, the method comprising providing a semiconductor structure with an active device area capped with a pad oxide layer bounded by one or more isolation trenches, providing a sacrificial oxide layer by thickening said pad oxide layer to a desired oxide thickness, in using said thickened pad oxide layer as said sacrificial oxide layer for device implantation, stripping said sacrificial pad oxide layer after use, and capping said semiconductor gate with a final gate oxide layer.

Gate processing method with reduced gate oxide corner and edge thinning

Two different gate conductor dielectric caps are used in the array and support device regions so that the bitline contact can be fabricated in the array region, but a thinner hard mask can be used for better linewidth control in the support device region. The thinner dielectric cap is made into dielectric spacers in the array device regions during support mask etching. These dielectric spacers allow for the array gate conductor resist line to be made smaller than the final gate conductor linewidth. This widens the array gate conductor processing window. The second dielectric cap layer improves linewidth control for the support devices and the array devices. Two separate gate conductor lithography steps and gate conductor dielectric etches are carried out in the present invention to optimize the gate conductor linewidth control in the array and support device regions. The gate conductors in the array and support devices regions are etched simultaneously to reduce production cost. In additional embodiments of the invention, dual workfunction support device transistors with or without salicide can be fabricated with an array including borderless contacts.

Modified gate processing for optimized definition of array and logic devices on same chip

A fully polysilicon encapsulated metal-containing damascene gate structure is provided that is useful in Gigabit DRAM (dynamic random access memory) device. The fully encapsulated metal-containing damascene gate comprises a semiconductor substrate having a gate oxide layer formed on a surface portion of said substrate; a gate polysilicon layer formed on said gate oxide layer; a metal layer formed on said polysilicon layer; and a cap oxide layer formed on said metal layer, wherein said metal layer is completely encapsulated by said polysilicon and oxide layers. The damascene gate structure may also include polysilicon spacers formed on said gate polysilicon layer and said metal layer is encapsulated therein and outer polysilicon sidewalls that are oxidized.

Fully encapsulated damascene gates for Gigabit DRAMs

Two different gate conductor dielectric caps are used in the array and support device regions so that the bitline contact can be fabricated in the array region, but a thinner hard mask can be used for better linewidth control in the support device region. The thinner dielectric cap is made into dielectric spacers in the array device regions during support mask etching. These dielectric spacers allow for the array gate conductor resist line to be made-smaller than the final gate conductor linewidth. This widens the array gate conductor processing window. The second dielectric cap layer improves linewidth control for the support devices and the array devices. Two separate gate conductor lithography steps and gate conductor dielectric etches are carried out in the present invention to optimize the gate conductor linewidth control in the array and support device regions. The gate conductors in the array and support devices regions are etched simultaneously to reduce production cost. In additional embodiments of the invention, dual workfunction support device transistors with or without salicide can be fabricated with an array including borderless contacts.

An integrated circuit device is presented. The integrated circuit device of the present invention comprises a semiconductor substrate having a combination of transistor gates formed using a conventional dielectric-capped gate stack for self-aligned diffusion contacts (SAC) as well as a transistor gate structure formed by removing the dielectric-cap gate stack from selected regions of the semiconductor substrate and replacing the dielectric-cap gate stack with a second gate conductor which is patterned using a damascene process.

Integrated circuit using damascene gate structure

A structure and method for simultaneously forming array structures and support structures on a substrate comprises forming the array structures to have a V-groove, forming the support structures to have a planar surface, and simultaneously forming a first oxide in the V-groove and a second oxide in the planar surface, wherein the first oxide is thicker than the second oxide.

Dual tox trench dram structures and process using V-groove

A semiconductor device includes a semiconductor substrate having an oxide layer thereon. A gate conductor is provided on the oxide layer, the gate conductor including a layer of polysilicon on the oxide layer, a tungsten silicide layer on the polysilicon layer, and a nitride cap layer on the tungsten silicide layer. The polysilicon layer has a length greater than length of the silicide layer and the nitride layer. Dielectric spacers on the gate conductor overlay the nitride cap layer and the tungsten silicide layer to provide a sidewall substantially flush with the polysilicon layer. Exposed polysilicon on the polysilicon layer is oxidized.

Modified gate conductor processing for poly length control in high density DRAMS

A memory device structure is provided in which the array oxide layer has a thickness that is greater than the thickness of the support oxide layer. Specifically, the structure comprises a semiconductor substrate having a gate oxide layer formed thereon, said substrate including array regions and support regions, said array regions include at least one patterned gate conductor, said patterned gate conductor having a polysilicon layer formed on said gate oxide layer, a conductor material layer formed on said polysilicon layer, and a nitride cap layer formed on said conductor material layer, said nitride cap layer and said conductor material layer having spacers formed on sidewalls thereof and said polysilicon layer having an array oxide layer formed on sidewalls thereof, said spacers being substantially flush with the oxide sidewalls, said support regions include at least one patterned gate conductor, said patterned gate conductor having a polysilicon layer formed on said gate oxide layer, a conductor material layer formed on said polysilicon layer, and a nitride cap layer on said conductor material layer, said polysilicon layer having a support oxide layer formed on sidewalls thereof, wherein said array oxide layer has a thickness that is greater than said support oxide layer.

Gate prespacers for high density, high performance DRAMs

Dual gate oxide process for uniform oxide thickness

Growing community of inventors

Pleasant Valley, NY, United States of America

Mary Elizabeth Weybright