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:
Nov. 09, 2004
Filed:
Aug. 14, 2003
Chin-Cheng Chien, Hsin-Chu, TW;
Hsiang-Ying Wang, Chia-Yi Hsien, TW;
Yu-Kun Chen, Hsin-Chu, TW;
Neng-Hui Yang, Hsin-Chu, TW;
United Microelectronics Corp., Hsin-Chu, TW;
Abstract
The present invention provides a novel MOS transistor structure. The MOS transistor includes a gate electrode formed on a semiconductor substrate, and a gate oxide layer formed between the gate electrode and the semiconductor substrate. A spacer is formed on each sidewall of the gate electrode. A lightly doped source/drain extension is formed under the spacer with a raised epitaxial layer interposed between the spacer and the semiconductor substrate. The epitaxial layer, which is part of the lightly doped source/drain extension, has a lattice constant that is greater than the lattice constant of silicon crystal. The epitaxial layer serves as a solubility enhancement layer that is capable of increasing active boron concentration, thereby reducing sheet resistance of the source/drain extension. A heavily doped source/drain region is formed in the semiconductor substrate next to the edge of the spacer. A raised silicide layer is formed on the heavily doped source/drain region.