An Investigation on the Diffraction and Absorption Effects of Proximity Lithography

• Main Authors: Jhy-Wei Fan, 范志威
• Other Authors: 蔡志成
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/96720367291800698801

碩士 === 國立中興大學 === 機械工程學系所 === 98 === Proximity lithography is one of the commonly employed processes for fabricating optics components and micro electromechanical system. However, patterns exposed on the photoresist often distored in the process due to optical diffraction and absorption effects of photoresist. It is an urge issue to investigate the effect. This study, based on the Dill''s model, investigates the effects of absorption of photoresist as well as near-field diffraction on the proximity lithography process. Experiments are also conducted to compare the developed model. The results showed that the intensity, but not the distribution, is affected by the exposure time. Chemical concentration on the photoresist changed in accordance to the exposure time. This concentration then affects the profile of exposed photoresist. The major contribution of this study is to analyze the combined effect of near-field diffraction and chemical concentration on the photoresist, which dominates the profile in the developing process, in the proximity lithography process.