The Mechanism of the desire process

Abstract

As we enter the megabit era the demands on the performance of lithographic processes are dramatically increased. Achieving submicron resolution with sufficient line width control on substrates with reflective topography is becoming a major problem. One way of solving most of the problems that are encountered in optical submicron lithography is by so called multilayer resist techniques [1]. Although excellent results can be obtained by this method it has the serious disadvantage of being too complicated for IC production lines. It is thus not surprising that much effort has been put into the development of simpler alternatives, such as the bilayer RIE/PCM resist scheme [2], in which a silicon containing resist is used as top layer. However, the major disadvantage of these systems is that by incorporating a sufficient amount of silicon in the resist material, its physical properties tend to degrade.