A method of forming a semiconductor device having two different strains therein is provided. The method includes forming a strain in a first region with a first straining film, and forming a second strain in a second region with a second straining film. Either of the first or second strains may be either...http://www.google.de/patents/US7932155?utm_source=gb-gplus-sharePatent US7932155 - Structure and method for performance improvement in vertical bipolar transistors
