Abstract: A semiconductor device comprises a gate electrode stack having sidewalls and a top surface with a gate dielectric layer and the gate electrode, and LDD/LDS regions in the substrate aligned with the stack. Conformal L-shaped etch-stop layers with a thickness from about 50 ? to about 200 ? are formed with a vertical leg on the sidewalls of the stack and a horizontal leg reaching over the LDD/LDS regions next to the stack. RSD regions are formed in contact with the substrate aside from the etch-stop layers. The RSD regions cover the horizontal leg of the etch-stop layer and cover at least a portion of the vertical leg of the etch-stop layer on the sidewall of the gate electrode.
Type:
Grant
Filed:
February 21, 2006
Date of Patent:
February 10, 2009
Assignee:
International Business Machines Corporation
Abstract: A method of forming CMOS semiconductor materials with PFET and NFET areas formed on a semiconductor substrate, covered respectively with a PFET and NFET gate dielectric layers composed of silicon oxide and different degrees of nitridation thereof. Provide a silicon substrate with a PFET area and an NFET area and form PFET and NFET gate oxide layers thereover. Provide nitridation of the PFET gate oxide layer above the PFET area to form the PFET gate dielectric layer above the PFET area with a first concentration level of nitrogen atoms in the PFET gate dielectric layer above the PFET area. Provide nitridation of the NFET gate oxide layer to form the NFET gate dielectric layer above the NFET area with a different concentration level of nitrogen atoms from the first concentration level. The NFET gate dielectric layer and the PFET gate dielectric layer can have the same thickness.
Type:
Grant
Filed:
September 9, 2003
Date of Patent:
November 23, 2004
Assignee:
International Business Machines Corporation
Inventors:
Anthony I-Chih Chou, Toshiharu Furukawa, Patrick R. Varekamp, Jeffrey W. Sleight, Akihisa Sekiguchi
Abstract: A method is provided for blocking implants from the gate electrode of an FET device. Form a first planarizing film covering the substrate and the gate electrode stack. The first planarizing film is planarized by either polishing or self-planarizing. For deposition by HDP or use of spin on materials, the film is self-planarizing. Where polishing is required, the first planarizing film is planarized by polishing until the top of the gate electrode is exposed. Etch back the gate electrode below the level of the upper surface of the first planarizing film. Then deposit a blanket layer of a second planarizing film and polish to planarize it to a level exposing the first planarizing film, forming the second planarizing film into an implantation block covering the top surface of the gate. Remove the first planarizing film. Form the counterdoped regions by implanting dopant into the substrate using the implantation block to block implantation of the dopant into the gate electrode.
Type:
Grant
Filed:
August 5, 2002
Date of Patent:
October 12, 2004
Assignee:
International Business Machines Corporation