US Patent 7384728 Method of fabricating a semiconductor device

A method of fabricating a semiconductor device. A first organic layer, a silicon-containing sacrificial layer, and a second organic layer are sequentially formed on a substrate. A photolithography process is performed for forming a predetermined pattern in the second organic layer. Thereafter, the second organic layer is utilized as an etching mask for etching the silicon-containing sacrificial layer till a surface of the first organic layer is exposed, thus transferring the predetermined pattern to the silicon-containing sacrificial layer. The silicon-containing sacrificial layer is utilized as an etching mask for etching the first organic layer till a surface of the substrate is exposed, thereby transferring the predetermined pattern to the first organic layer. Then, the silicon-containing sacrificial layer and the first organic layer are utilized as an etching mask for etching the substrate, thereby transferring the predetermined pattern to the substrate. Finally, the first organic layer is removed from the substrate.