Method of Forming A Semiconductor Device Including A Pitch Multiplication

A method comprising:

• forming a hard-mask layer over a semiconductor substrate;
• forming a first layer over the hard-mask layer;
• forming a second layer over the first layer;
• forming a third layer over the second layer;
• forming a line-and-space pattern over the third layer, the line-and-space pattern comprising a plurality of line portions and a plurality of space portions each between associated adjacent two of the plurality of line portions;
• transferring the line-and-space pattern to each of the third and second layers so that each of the third and second layers has the line-and-space pattern;
• converting the line-and-space pattern of the second layer into a modified pattern in which each of the plurality of line portions in the line-and-space pattern is divided into a plurality of island portions;
• transferring the modified pattern of the second layer to each of the first layer and the hard-mask layer so that each of the first layer and the hard-mask layer has the modified pattern;
• and
• selectively removing the semiconductor substrate by using the hard-mask layer having the modified pattern as an etching mask to define a plurality of active regions in the semiconductor substrate, each of the plurality of active regions corresponding to an associated one of the plurality of island portions of the modified pattern.

A method comprising:

• forming a hard-mask layer over a semiconductor substrate;
• forming a first layer over the hard-mask layer;
• forming a second layer over the first layer;
• forming a third layer over the second layer;
• forming a line-and-space pattern over the third layer, the line-and-space pattern comprising a plurality of line portions and a plurality of space portions each between associated adjacent two of the plurality of line portions, the line and space pattern comprising:
• at least some of the line-and-space pattern over the third layer comprises a first organic film, said at least some of the line-and-space pattern over the third layer comprises a silicon-containing film above the first organic film;
• and
• another some of the line-and-space pattern over the third layer comprises silicon oxide, said another some of the line-and-space pattern over the third layer comprises a second organic film above the silicon oxide;
• transferring the line-and-space pattern to each of the third and second layers so that each of the third and second layers has the line-and-space pattern;
• converting the line-and-space pattern of the second layer into a modified pattern in which each of the plurality of line portions in the line-and-space pattern is divided into a plurality of island portions;
• transferring the modified pattern of the second layer to each of the first layer and the hard-mask layer so that each of the first layer and the hard-mask layer has the modified pattern;
• and
• selectively removing the semiconductor substrate by using the hard-mask layer having the modified pattern as an etching mask to define a plurality of active regions in the semiconductor substrate, each of the plurality of active regions corresponding to an associated one of the plurality of island portions of the modified pattern.