OPTICAL PROXIMITY CORRECTION - MASK PATTERN-GENERATION CHALLENGES

The requirements imposed by optical proximity correction (OPC) on mask making, i.e. pattern generation, are addressed. Dry etching of MoSi i s proposed to deal with the need for improved resolution. E-beam proxi mity correction (EPC) is used for more accurate linewidth control. An appropriate pre-correction fracturing technique is presented. A MoSi b ased embedded phase shift mask (5X) has been produced with a critical dimension of 0.3 mu m using OPC corrected data. Highly accurate linewi dth control was achieved by the reduction of the e-beam proximity effe ct and linearity errors to less than 3%. The effect of OPC and EPC on mask making throughput are discussed. An alternative OPC strategy is s uggested that is more compatible with exposure grid requirements.