Patent ID: 6656816
Filing Date: 2003-12-02
Classification: H01L

Abstract:
A method for manufacturing a semiconductor device, comprising the steps of:forming a first ion implantation expendable film on a first conductive type semiconductor substrate; forming a film for an etching mask on said first ion implantation expendable film; patterning said film for the etching mask into a shape of an active region and of a field region; forming a first mask pattern by a photolithography method in accordance with said film for the etching mask which has been patterned; introducing first or second conductive type dopant into said first conductive type semiconductor substrate; forming a trench groove on said first conductive type semiconductor substrate, after removing said mask pattern, by an etching method using said film for the etching mask as a mask; forming an insulation film in said trench groove; forming a first well by carrying out an annealing thermal treatment; flattening said insultation film after forming said trench groove; selectively removing said film for the etching mask; removing the whole of said first ion implantation expendable film; forming a second ion implantation expendable film on said first conductive type semiconductor substrate; forming a second mask pattern shape by a photolithography method in accordance with said trench groove; and forming a second well by introducing another first or second conductive type dopant into said first conductive type semiconductor substrate.