Semiconductor device manufacturing: process – Formation of electrically isolated lateral semiconductive... – Implanting to form insulator
Reexamination Certificate
2006-03-21
2006-03-21
Wilczewski, Mary (Department: 2822)
Semiconductor device manufacturing: process
Formation of electrically isolated lateral semiconductive...
Implanting to form insulator
C438S449000, C438S530000, C438S766000, C438S773000, C438S981000
Reexamination Certificate
active
07015111
ABSTRACT:
A sidewall oxidation process for use during the formation of a transistor such as a flash memory cell allows for improved control of a gate oxide profile. The method comprises doping transistor source and drain regions to different doping levels, then performing a transistor sidewall oxidation using a particular process to modify the gate oxide thickness. The oxide forms at a faster rate along the source sidewall than along the drain sidewall. By using ranges within the oxidation environment described, a source side gate oxide having a variable and selectable thickness may be formed, while forming a drain-side oxide which has a single thickness where a thinner layer is desirable. This leads to improved optimization of key competing requirements of a flash memory cell, such as program and erase performance, while maintaining sufficient long-term data retention. The process may allow improved cell scalability, shortened design time, and decreased manufacturing costs.
REFERENCES:
patent: 4409723 (1983-10-01), Harari
patent: 5102814 (1992-04-01), Woo
patent: 5115296 (1992-05-01), Hsue et al.
patent: 5192872 (1993-03-01), Lee
patent: 5382534 (1995-01-01), Sheu et al.
patent: 5445984 (1995-08-01), Hong et al.
patent: 5604366 (1997-02-01), Lee
patent: 5684317 (1997-11-01), Hwang
patent: 5814853 (1998-09-01), Chen
patent: 6251751 (2001-06-01), Chu et al.
patent: 6372663 (2002-04-01), Yeh et al.
patent: 6461915 (2002-10-01), Rudeck
patent: 6541393 (2003-04-01), Sugizaki et al.
patent: 6586806 (2003-07-01), Pai et al.
Powell Don C.
Rudeck Paul J.
Martin Kevin D.
Thomas Toniae M.
Wilczewski Mary
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