Processing chemically amplified resists on advanced photomasks using a thermal array

Abstract

A thermal array, which consists of a dense distribution of multivariate controlled heat/chill elements, is developed to achieve temperature uniformity of a quartz photomask throughout the processing temperature cycle of ramp, hold and quench. The thermal array spatially tunes the uniformity in response to calibrated feedback provided by temperature sensor instrumented masks or by linewidth data. The system can stabilize to decreases in temperature setpoints at fast rates, about 40 °C/min, to improve the throughput of the tool for situations requiring switching between operating temperatures. The thermal array is a likely aid to improve critical dimension distribution on expensive photomasks by providing uniform thermal processing conditions. © 2003 Elsevier B.V. All rights reserved.