US Patent 7351622 Methods of forming semiconductor device

A method of forming a semiconductor device includes forming a three-dimensional structure formed of a semiconductor on a semiconductor substrate, and isotropically doping the three-dimensional structure by performing a plasma doping process using a first source gas and a second source gas. The first source gas includes n-type or p-type impurity elements, and the second source gas includes a dilution element regardless of the electrical characteristic of a doped region.