Evaluating Photoresist Dissolution, Swelling, and Removal with an In Situ Film Refractive Index and Thickness Monitor
Evaluating Photoresist Dissolution, Swelling, and Removal with an In Situ Film Refractive Index and Thickness Monitor
复制标题
使用原位薄膜折射率和厚度监测仪评估光刻胶溶解、膨胀和去除
DOI：
10.1149/1.1817716
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发表时间：
2005
影响因子：
3.9
通讯作者：
D. Hess
中科院分区：
文献类型：
--
作者：
Matthew Spuller;R. Perchuk;D. Hess
在电子、光学和机械设备以及集成电路的制造过程中，光致抗蚀剂薄膜的溶解和去除被执行多次。有关折射率和薄膜厚度变化的信息对于此类过程的设计和建模是有意义的。光谱反射法是一种成本效益高的技术，它已被用于监测薄膜厚度，但仅限于薄膜在溶解期间折射率恒定的应用，因此具有已知的价值。本文扩展了传统的光谱反射仪分析，以解释薄膜在加工过程中的折射率变化。用这种方法得到的结果与椭圆偏振光谱测量结果有很好的相关性。该技术可应用于光致抗蚀剂在水基溶液中的溶解、光致抗蚀剂在溶剂蒸气中的溶胀和在水-乙醇混合物中的去除，并可类似地应用于其他薄膜应用。此外，可用于处理薄膜材料的流体，如水和非水溶剂、超临界或亚临界混合物和气体膨胀液体的光学性质，可以使用光谱反射仪进行监测。
Dissolution and removal of photoresist films is performed numerous times during the fabrication of electronic, optical, and mechanical devices and integrated circuits. Information regarding changes in refractive index andfilm thickness is of interest for the design and modeling of such processes. Spectroscopic reflectometry is a cost-effective technique that has been used to monitor film thickness, but has been limited to applications in which the film refractive index is constant during dissolution, and thus has a known value. This paper extends conventional spectroscopic reflectometry analysis to account for refractive index changes in films during processing. Results obtained by this approach correlate well with spectroscopic ellipsometry measurements. This technique is applied to the dissolution of photoresist in aqueous base solutions, swelling of photoresist in solvent vapor, and removal of photoresist in water-alcohol mixtures, and can similarly be applied to other thin film applications. In addition, the optical properties of fluids such as aqueous and non-aqueous solvents, supercritical or subcritical mixtures, and gas-expanded liquids, which can be used to process thin film materials, can be monitored using spectroscopic reflectometry.