The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 06, 1999
Filed:
Dec. 22, 1997
Taiwan Semiconductor Manufacturing Company, Ltd., Hsin-Chu, TW;
Abstract
A shallow trench isolated FET LDD structure that has a low probability of short circuiting at the silicon to trench interface or between the source or drain and the gate (because of a titanium silicide bridge) is described. It is based on an isolation trench having a top portion with vertical sides and a lower portion with sloping sides. With the filled trench in place, along with a polysilicon gate and gate oxide, the thinner, lightly doped, N type layer is formed using ion implantation. Spacers are then formed on the gate but, prior to the second ion implant step, a few hundred Angstroms of silicon is selectively removed from the surface. This causes the trench filler material to extend above the wafer surface and the spacers to extend above the gate. A deeper, more strongly N-type, layer is then formed in the usual way, followed by the standard SALICIDE process for making contact to source, gate, and drain.