| 摘要 |
PURPOSE:To prevent etching defects after reactive ion etching(RIE) and improve the precision of the formation pattern by shifting the focus during exposure. CONSTITUTION:After coating the surface of the SiO2 process substrate 2 with a g-line positive photoresist and baking on a hot plate, a specially designed reticule and g-line stepper with a 0.54 N.A. (lens opening) are used and the pattern is transferred after shifting the focus 0.5mum from the best focus point in the direction of shortening the distance between the process substrate 2 and the lens. After that, when the post exposure bake is completed, the development process is performed and a resist pattern l is obtained. By shifting the focus during exposure in this way, the more minute the pattern is, the more possible it is to taper resist patterns and minimize the microloading effect during RIE processing. As a result, the occurrence of etching defects can be prevented and the precision of the formation pattern can be increased. |
