Method for manufacturing a semiconductor device

A pattern forming method for a semiconductor device, the pattern forming method comprising:

• forming, over a semiconductor substrate, a stacked structure of a bottom layer, a middle layer disposed over the bottom layer and a first mask layer disposed over the middle layer, the middle layer including a first cap layer disposed over the bottom layer, an intermediate layer disposed over the first cap layer and a second cap layer disposed over the intermediate layer;
• patterning the first mask layer by using a first resist pattern formed on the first mask layer as an etching mask;
• patterning the second cap layer by using the patterned first mask layer as an etching mask;
• forming a second mask layer over the patterned second cap layer, which has been patterned by using the patterned first mask layer;
• patterning the second mask layer by using a second resist pattern formed on the second mask layer as an etching mask;
• patterning the patterned second cap layer, which has been patterned by using the patterned first mask layer, by using the patterned second mask layer as an etching mask;
• forming a third mask layer over the patterned second cap layer, which has been patterned by using the patterned second mask layer;
• patterning the third mask layer by using a third resist pattern formed on the third mask layer as an etching mask;
• patterning the patterned second cap layer, which has been patterned by using the patterned second mask layer, by using the patterned third mask layer as an etching mask;
• patterning the intermediate layer and the first cap layer by using the patterned second cap layer, which has been patterned by using the patterned third mask layer, as an etching mask;
• and
• patterning the bottom layer by using the patterned first cap layer as an etching mask, and
• forming a bulk spacer layer in the patterned intermediate and first cap layers and sidewall spacers on sidewalls of the patterned intermediate and first cap layers,
• wherein the first resist pattern and the second resist pattern extend to cross each other and have a first overlapped opening portion where a part of an opening pattern of the second resist pattern overlaps a part of an opening pattern of the first resist pattern.

A pattern forming method for a semiconductor device, the pattern forming method comprising:

• forming, over a semiconductor substrate, a stacked structure of a bottom layer, a middle layer disposed over the bottom layer and a first mask layer disposed over the middle layer, the middle layer including a first cap layer disposed over the bottom layer, an intermediate layer disposed over the first cap layer and a second cap layer disposed over the intermediate layer;
• patterning the first mask layer by using a first resist pattern as an etching mask;
• patterning the second cap layer by using the patterned first mask layer as an etching mask;
• forming a second mask layer over the patterned second cap layer, which has been patterned by using the patterned first mask layer;
• patterning the second mask layer by using a second resist pattern as an etching mask;
• patterning the patterned second cap layer, which has been patterned by using the patterned first mask layer, by using the patterned second mask layer as an etching mask;
• patterning the intermediate layer and the first cap layer by using the patterned second cap layer, which has been patterned by using the patterned second mask layer, as an etching mask;
• and
• forming a bulk spacer layer in the patterned intermediate and first cap layers and sidewall spacers on sidewalls of the patterned intermediate and first cap layers,
• wherein the intermediate layer is made of an amorphous silicon.