Patent ID: 7291560

Claim:
A method of forming a semiconductor device, the method comprising: providing a substrate with a pattern layer that is structured in separate striplike parts running parallel to one another, said striplike parts having sidewalls and lateral dimensions which are the same for each one of said parts, said striplike parts being arranged at a distance from one another, said distance being the same for every two neighboring ones of said portions; applying a first spacer layer conformally on said patter layer; etching said first spacer layer anisotropically to form first spacers on said sidewalls of said striplike parts; removing said pattern layer, leaving said first spacers with two main sidewalls each; applying a second spacer layer conformally; etching said second spacer layer anisotronically to form second spacers on said sidewalls of said first spacers so that free spaces remain between pairs of said second spacers that are located on sidewalls that face one another; applying a complementary layer to fill said free spaces; planarizing upper surfaces of said first spacers, said second spacers and said complementary layer; removing at least one layer selected from the group consisting of first spacers, second spacers, complementary layer, both first and second spacers, both first spacers and complementary layer, and both second spacers and complementary layer; and using at least one remaining layer selected from the group consisting of both second spacers and complementary layer, both first spacers and complementary layer, both first and second spacers, complementary layer, second spacers, and first spacers as a mask to etch a further layer or layer sequence located underneath into striplike parts.