DRY ETCHING FOR SILYLATED RESIST DEVELOPMENT

Dry developable resist systems based on silylation have been presented as an alternative solution for submicron and deep submicron lithography. The DESIRE process (Diffusion Enhanced Silylated Resist) is the most well-known example of such a process. In this paper the dry development step using reactive ion etching has been investigated using a TEGAL MCR (magnetically confined reactor). The MCR system is a versatile tool which provides two major improvements over classical RIE: the magnetical confinement of the plasma and the triode RF coupling system. In this paper the influence of the pressure, the bias power and the oxygen flow on the etch rate and the shape of the photoresist pattern was investigated. The etch rate of the resist and associated uniformity depend on the plasma etching parameters. The exposure dose is however the major parameter determining the critical dimension (CD).