Patent ID: 7994016

Claim:
A method of forming ultra-shallow p-type lightly doped drain (LDD) regions in a surface of a substrate for PMOS transistors comprising: providing a gaseous mixture of an inert gas, a boron-containing source, and a carbon-containing source, wherein the concentration of the gaseous mixture is at least 99.5% dilute with the inert gas and the carbon-containing source; forming the gaseous mixture into a plasma; forming the LDD regions, wherein the forming step includes plasma-doping the boron into the substrate using the plasma; and forming n-type pocket regions in the substrate, each n-type pocket region positioned underneath and adjacent to a respective LDD region, wherein the carbon-containing source is CH 4 and the boron-containing source is B 2 H 6 , and wherein the carbon-containing source and boron-containing source are provided in substantially equal concentrations and the gaseous mixture is between about 99.0-99.2% dilute with the inert gas.