International Business Machines Corporation

Ricky S Amos

Cyril Cabral, Jr

Diane Catherine Boyd

Anda C Mocuta

An L Steegen

Victor Ku

Vijay Narayanan

Jakub Tadeusz Kedzierski

Ying Li

Richard D Kaplan

Woo-Hyeong Lee

Zhijiong Luo

Evgeni Petrovich Gousev

Meikei Ieong

Henry K Utomo

Wesley Charles Natzle

Huajie Chen

Nivo Rovedo

Siddhartha Panda

Dan Mihai Mocuta

Brian L Tessier

Douglas A Buchanan

Maheswaren Surendra

Ramachandra Divakaruni

Arne Watson Ballantine

Douglas Duane Coolbaugh

Kenneth Parker Rodbell

Supratik Guha

Herbert Lei Ho

Bomy A Chen

Fenton Read McFeely

Paul Christian Parries

Alessandro Cesare Callegari

Maheswaran Surendra

Thomas Safron Kanarsky

John Jacob Yurkas

Douglas Andrew Buchanan

Hyungjun Kim

Heidi L Greer

Gary L Patton

MeiKei Leong

Kevin E Mello

Bryant C Colwill

Katayun Barmak

Gregory Bazan

Joseph F Kudlacik

Bernard P Leroy

A semiconductor structure is fabricated with reduced gate capacitance by thinning of a gate electrode to provide a reduced thickness gate electrode. The gate electrode is thinned after forming a spacer layer adjoining the gate electrode. In addition, the height of the spacer layer may also be reduced. The spacer layer thus has an enhanced horizontal width desired for locating an intrinsic source/drain with respect to an extension region and in particular, an enhanced horizontal width relative to the spacer height. The reduced thickness gate electrode may be fully silicided to provide decreased gate resistance. A raised source/drain layer may be located upon the intrinsic source/drain region. The raised source/drain layer may have a top surface higher than the reduced thickness gate electrode. In addition, the raised source/drain layer may have a top surface higher than the reduced height spacer layer.

Field effect device with reduced thickness gate

A multilayer embedded stressor having a graded dopant profile for use in a semiconductor structure for inducing strain on a device channel region is provided. The inventive multilayer stressor is formed within areas of a semiconductor structure in which source/drain regions are typically located. The inventive multilayer stressor includes a first conformal epi semiconductor layer that is undoped or lightly doped and a second epi semiconductor layer that is highly dopant relative to the first epi semiconductor layer. The first and second epi semiconductor layers each have the same lattice constant, which is different from that of the substrate they are embedded in. The structure including the inventive multilayer embedded stressor achieves a good balance between stress proximity and short channel effects, and even eliminates or substantially reduces any possible defects that are typically generated during formation of the deep source/drain regions.

Structure and method to form multilayer embedded stressors

A method for fabricating a CMOS gate electrode by using Re, Rh, Pt, Ir or Ru metal and a CMOS structure that contains such gate electrodes are described. The work functions of these metals make them compatible with current pFET requirements. For instance, the metal can withstand the high hydrogen pressures necessary to produce properly passivated interfaces without undergoing chemical changes. The thermal stability of the metal on dielectric layers such as SiO, AlOand other suitable dielectric materials makes it compatible with post-processing temperatures up to 1000&#xb0; C. A low temperature/low pressure CVD technique with Re(CO)as the source material is used when Re is to be deposited.

High temperature processing compatible metal gate electrode for pFETS and methods for fabrication

The present invention provides a complementary metal oxide semiconductor integration process whereby a plurality of silicided metal gates are fabricated atop a gate dielectric. Each silicided metal gate that is formed using the integration scheme of the present invention has the same silicide metal phase and substantially the same height, regardless of the dimension of the silicide metal gate. The present invention also provides various methods of forming a CMOS structure having silicided contacts in which the polySi gate heights are substantially the same across the entire surface of a semiconductor structure.

CMOS silicide metal gate integration

Embodiments herein present a method for a feed forward silicide control scheme based on spacer height controlling pre-clean time. The method forms field effect transistor gates over a substrate and then forms spacers on the gates. Next, the method measures the spacers using an atomic force microscope to determine a measured spacer height. The method then conducts a pre-cleaning etch, wherein a duration of the pre-cleaning is adjusted according to the measured spacer height. If the measured spacer height is below a predetermined amount, the duration of the pre-cleaning is reduced; and, if the measured spacer height is above a predetermined amount, the duration of the pre-cleaning is increased.

Feed forward silicide control scheme based on spacer height controlling preclean time

Silicide is introduced into the gate region of a CMOS device through different process options for both conventional and replacement gate types processes. Placement of silicide in the gate itself, introduction of the silicide directly in contact with the gate dielectric, introduction of the silicide as a fill on top of a metal gate all ready in place, and introduction the silicide as a capping layer on polysilicon or on the existing metal gate, are presented. Silicide is used as an option to connect between PFET and NFET devices of a CMOS structure. The processes protect the metal gate while allowing for the source and drain silicide to be of a different silicide than the gate silicide. A semiconducting substrate is provided having a gate with a source and a drain region. A gate dielectric layer is deposited on the substrate, along with a metal gate layer. The metal gate layer is then capped with a silicide formed on top of the gate, and conventional formation of the device then proceeds. A second silicide may be employed within the gate. A replacement gate is made from two different metals (dual metal gate replacement) prior to capping with a silicide.

Process options of forming silicided metal gates for advanced CMOS devices

High performance (surface channel) CMOS devices with a mid-gap work function metal gate are disclosed wherein an epitaxial layer is used for a threshold voltage Vt adjust/decrease for the PFET area, for large Vt reductions (&#x2dc;500 mV), as are required by CMOS devices with a mid-gap metal gate. The present invention provides counter doping using an in situ B doped epitaxial layer or a B and C co-doped epitaxial layer, wherein the C co-doping provides an additional degree of freedom to reduce the diffusion of B (also during subsequent activation thermal cycles) to maintain a shallow B profile, which is critical to provide a surface channel CMOS device with a mid-gap metal gate while maintaining good short channel effects. The B diffusion profiles are satisfactorily shallow, sharp and have a high B concentration for devices with mid-gap metal gates, to provide and maintain a thin, highly doped B layer under the gate oxide.

High performance CMOS device structure with mid-gap metal gate

Methods of forming complementary metal oxide semiconductor (CMOS) devices having multiple-threshold voltages which are easily tunable are provided. Total salicidation with a metal bilayer (representative of the first method of the present invention) or metal alloy (representative of the second method of the present invention) is provided. CMOS devices having multiple-threshold voltages provided by the present methods are also described.

Method and process to make multiple-threshold metal gates CMOS technology

High performance (surface channel) CMOS devices with a mid-gap work function metal gate are disclosed wherein an epitaxial layer is used for a threshold voltage Vt adjust/decrease for the PFET area, for large Vt reductions (&tilde;500 mV), as are required by CMOS devices with a mid-gap metal gate. The present invention provides counter doping using an in situ B doped epitaxial layer or a B and C co-doped epitaxial layer, wherein the C co-doping provides an additional degree of freedom to reduce the diffusion of B (also during subsequent activation thermal cycles) to maintain a shallow B profile, which is critical to provide a surface channel CMOS device with a mid-gap metal gate while maintaining good short channel effects. The B diffusion profiles are satisfactorily shallow, sharp and have a high B concentration for devices with mid-gap metal gates, to provide and maintain a thin, highly doped B layer under the gate oxide.

A method for forming a thermally stable ohmic contact structure that includes a region of monocrystalline semiconductor and a region of polycrystalline semiconductor. At least one region of dielectric material is formed between at least a portion of the region of monocrystalline semiconductor and the region of polycrystalline semiconductor, thereby controlling grain growth of the polycrystalline semiconductor.

Method of forming thermally stable polycrystal to single crystal electrical contact structure

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Rhinebeck, NY, United States of America

Ricky S Amos