Dependence of dose rate on the sensitivity of the resist under ultra-high flux extreme ultraviolet (EUV) pulse irradiation

Abstract

Abstract Efforts are being focused on increasing the power of extreme ultraviolet (EUV) light sources used in semiconductor manufacturing to increase the throughput. As a result, the investigation of the effect of high power sources on resist materials is a critical issue. A chemically amplified resist (CAR) and a non-CAR were irradiated with 13.5 nm EUV high-flux pulses from a soft X-ray free-electron laser (FEL). In the non-CAR, the positive-tone resist (ZEP520A) exhibited lower sensitivity at high irradiation densities, while the negative-tone resist exhibited a higher sensitivity. In addition, the dose rate did not considerably affect the sensitivity of the CAR.