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:
Jun. 15, 2010
Filed:
Jan. 10, 2008
Puneet Kohli, Austin, TX (US);
Manoj Mehrotra, Plano, TX (US);
Shaoping Tang, Plano, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
Pipe defects in n-type lightly doped drain (NLDD) regions and n-type source/drain (NDS) regions are associated with arsenic implants, while excess diffusion in NLDD and NSD regions is mainly due to phosphorus interstitial movement. Carbon implantation is commonly used to reduce phosphorus diffusion in the NLDD, but contributes to gated diode leakage (GDL). In high threshold NMOS transistors GDL is commonly a dominant off-state leakage mechanism. This invention provides a method of forming an NMOS transistor in which no carbon is implanted into the NLDD, and the NSD is formed by a pre-amorphizing implant (PAI), a phosphorus implant and a carbon species implant. Use of carbon in the NDS allows a higher concentration of phosphorus, resulting in reduced series resistance and reduced pipe defects. An NMOS transistor with less than 1·10cmarsenic in the NSD and a high threshold NMOS transistor formed with the inventive method are also disclosed.