Patterning of 32 nm 1: 1 Line and Space by Resist Reflow Process

Producing a sub-32nm line and space pattern is one of the most important issues in semiconductor manufacturing. In particular, it is important 10 produce line and space patterns in flash memory-type devices because the unit cell is mostly composed of line and space patterns. The double patterning method is regarded as the most promising technology for producing, a sub-32 nm half-pitch node. However. the double patterning method is expensive for the production and a heavy data split is required. In order to achieve cheaper and easier patterning, we propose a resist reflow process (RRP) for producing 32 nm 1 : 1 line and space patterns. In many cases, it is easier to produce a 1 : 3 pitch line and space pattern than a 1 : 1 pitch line and space pattern ill terms of the aerial image. and RRP can transform a 1 : 3 pitch aerial image to a 1 : 1 resist image. We used a home-made RRP simulation based on the Navier-Stokes equation including the surface tension effect. Solid-E of Synopsis is used for the optical simulation, and electron-beam lithography is used for the experiment to verify the concept.