The study of CD behavior due to transmission control position change within photomask substrate

摘要

As design rule of memory device is smaller and smaller, the CD uniformity of a photomask become the mostimportant factor to satisfy wafer exposure performance. Once the photomask is made, CD uniformity of the maskcan't be changed and if CD uniformity of the mask is not good to use for wafer exposure, we must reject it andmake another one again. But, after applying transmission control tool for CD uniformity, we have an extra chance to control mask CD uniformity in one mask and this is very effective for wafer printing result. In this paper, we are going to evaluate the behavior of wafer CD due to transmission control position change within photomask substrate and find the optimum control position for better wafer result.