International Business Machines Corporation

Globalfoundries Inc.

Michael D Steigerwalt

Herbert Lei Ho

Mahender Kumar

Christopher D Sheraw

Paul A Papworth

Qiqing Christine Ouyang

Dominic Joseph Schepis

Judson Robert Holt

David M Dobuzinsky

Denise Pendleton

Brian Joseph Greene

Johnathan E Faltermeier

William K Henson

Rohit Pal

Atul Champaklal Ajmera

Kuldeep Amarnath

Johan W Weijtmans

Devendra K Sadana

Linda R Black

Brian W Messenger

Eric C T Harley

Rick J Carter

Karen Ann Bard

Qiging Ouyang

Brian L Walsh

Mahendar Kumar

A low energy surface is formed by a high temperature anneal of the surfaces of trenches on each side of a gate stack. The material of the semiconductor layer reflows during the high temperature anneal such that the low energy surface is a crystallographic surface that is at a non-orthogonal angle with the surface normal of the semiconductor layer. A lattice mismatched semiconductor material is selectively grown on the semiconductor layer to fill the trenches, thereby forming embedded lattice mismatched semiconductor material portions in source and drain regions of a transistor. The embedded lattice mismatched semiconductor material portions can be in-situ doped without increasing punch-through. Alternately, a combination of intrinsic selective epitaxy and ion implantation can be employed to form deep source and drain regions.

Self-aligned embedded SiGe structure and method of manufacturing the same

Methods of integrating reverse embedded silicon germanium (SiGe) on an NFET and SiGe channel on a PFET, and a related structure are disclosed. One method may include providing a substrate including an NFET area and a PFET area; performing a single epitaxial growth of a silicon germanium (SiGe) layer over the substrate; forming an NFET in the NFET area, the NFET including a SiGe plug in a channel thereof formed from the SiGe layer; and forming a PFET in the PFET area, the PFET including a SiGe channel formed from the SiGe layer. As an option, the SiGe layer over the PFET area may be thinned.

Methods of integrating reverse eSiGe on NFET and SiGe channel on PFET, and related structure

The present invention provides a 'collector-less' silicon-on-insulator (SOI) bipolar junction transistor (BJT) that has no impurity-doped collector. Instead, the inventive vertical SOI BJT uses a back gate-induced, minority carrier inversion layer as the intrinsic collector when it operates. In accordance with the present invention, the SOI substrate is biased such that an inversion layer is formed at the bottom of the base region serving as the collector. The advantage of such a device is its CMOS-like process. Therefore, the integration scheme can be simplified and the manufacturing cost can be significantly reduced. The present invention also provides a method of fabricating BJTs on selected areas of a very thin BOX using a conventional SOI starting wafer with a thick BOX. The reduced BOX thickness underneath the bipolar devices allows for a significantly reduced substrate bias compatible with the CMOS to be applied while maintaining the advantages of a thick BOX underneath the CMOS.

Ultra-thin SOI vertical bipolar transistors with an inversion collector on thin-buried oxide (BOX) for low substrate-bias operation and methods thereof

The present invention provides a 'subcollector-less' silicon-on-insulator (SOI) bipolar junction transistor (BJT) that has no impurity-doped subcollector. Instead, the inventive vertical SOI BJT uses a back gate-induced, majority carrier accumulation layer as the subcollector when it operates. The SOI substrate is biased such that the accumulation layer is formed at the bottom of the first semiconductor layer. The advantage of such a device is its CMOS-like process. Therefore, the integration scheme can be simplified and the manufacturing cost can be significantly reduced. The present invention also provides a method of fabricating BJTs on selected areas of a very thin BOX using a conventional SOI starting wafer with a thick BOX. The reduced BOX thickness underneath the bipolar devices allows for a significantly reduced substrate bias compatible with the CMOS to be applied while maintaining the advantages of a thick BOX underneath the CMOS. A back-gated CMOS device is also provided.

Vertical bipolar transistor with a majority carrier accumulation layer as a subcollector for SOI BiCMOS with reduced buried oxide thickness for low-substrate bias operation

The present invention provides a a method of fabricating bipolar junction transistors (BJTs) on selected areas of a very thin buried oxide (BOX) using a conventional silicon-on-insulator (SOI) starting wafer with a thick BOX. The reduced BOX thickness underneath the bipolar devices allows for a significantly reduced substrate bias compatible with the CMOS to be applied while maintaining the advantages of a thick BOX underneath the CMOS.

Method of fabricating a vertical bipolar transistor with a majority carrier accumulation layer as a subcollector for SOI BiCMOS with reduced buried oxide thickness

Methods for forming or etching silicon trench isolation (STI) in a silicon-on-insulator (SOI) region and a bulk silicon region, and a semiconductor device so formed, are disclosed. The STI can be etched simultaneously in the SOI and bulk silicon regions by etching to an uppermost silicon layer using an STI mask, conducting a timed etch that etches to a desired depth in the bulk silicon region and stops on a buried insulator of the SOI region, and etching through the buried insulator of the SOI region. The buried insulator etch for this process can be done with little complexity as part of a hardmask removal step. Further, by choosing the same depth for both the bulk and SOI regions, problems with a subsequent CMP process are avoided. The invention also cleans up the boundary between the SOI and bulk regions where silicon nitride residuals may exist.

STI formation in semiconductor device including SOI and bulk silicon regions

The present invention provides a method of fabricating a patterned silicon-on-insulator substrate which includes dual depth SOI regions or both SOI and non-SOI regions within the same substrate. The method of the present invention includes forming a silicon mask having at least one opening on a surface of Si-containing material, recessing the Si-containing material through the at least one opening using an etching process to provide a structure having at least one recess region and a non-recessed region, and forming a first buried insulating region in the non-recessed region and a second buried insulating region in the recessed region. In accordance with the present invention, the first buried insulating region in the non-recessed region is located above the second buried isolation region in the recessed region. A lift-off step can be employed to remove the first buried insulating region and the material that lies above to provide a substrate containing both SOI and non-SOI regions.

Patterning SOI with silicon mask to create box at different depths

A method for etching a silicon on insulator (SOI) substrate includes opening a hardmask layer formed on an SOI layer, and etching through the SOI layer, a buried insulator layer underneath the SOI layer, and a bulk silicon layer beneath the buried insulator layer using a single etch step.

Method for deep trench etching through a buried insulator layer

A DRAM array in an SOI wafer having a uniform BOX layer extending throughout the array eliminates the collar oxide step in processing; connects the buried plates with an implant that, in turn, is connected to a conductive plug extending through the device layer and the box that is biased at ground; while the pass transistors are planar NFETs having floating bodies that have a leakage discharge path to ground through a grounded bitline.

SOI trench capacitor cell incorporating a low-leakage floating body array transistor

The present invention provides a method of formed a nitrided surface layer atop a polysilicon gate electrode that inhibits the growth of an epi silicon layer thereon. Specifically, the method of the present invention includes the steps of: forming a polysilicon layer atop a gate dielectric layer, forming a nitrided surface layer on the polysilicon layer; selectively removing portions of the nitrided surface layer and the polysilicon layer stopping on the gate dielectric layer, while leaving a patterned stack of the nitrided surface layer and the polysilicon layer on the gate dielectric layer; forming sidewall spacers on at least exposed vertical sidewalls of polysilicon layer; removing portions of the gate dielectric layer not protected by the sidewall spacers; and growing an epi silicon layer on exposed horizontal surfaces of an underlying semiconductor substrate.

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Newburgh, NY, United States of America

Michael D Steigerwalt