With respect to the selective ratio in the etching process, it is an object to give design freedom in size of an LDD overlapped with a gate electrode, which is formed in a self-aligning manner, by performing an etching process under an etching condition that has a high selective ratio between a mask...http://www.google.de/patents/US7253044?utm_source=gb-gplus-sharePatent US7253044 - Manufacturing method for semiconductor device