高壓暨高溫環境下之單晶矽非等向性濕式蝕刻特性研究

Studies on anisotropic wet etching characteristics of single crystal silicon under high pressure and high temperature conditions

楊証皓(Cheng-Hao Yang)

指導教授 ： 楊啟榮 ； 程金保

國立臺灣師範大學/科技學院/機電科技研究所/碩士(2004年)

摘要

非等向性濕式矽蝕刻製程是體型矽微加工關鍵技術之一，而其技術發展重點在於如何提升蝕刻面的蝕刻速率與表面粗糙度。由於傳統的磁石攪拌方式有無法均勻地改善蝕刻速率與蝕刻粗糙度的缺點，而超音波震盪的方式雖可改善蝕刻表面粗糙度，但蝕刻速率改善的幅度卻不大，亦不適用於製作薄膜微結構。因此為改善以上機械攪拌式的缺點，本研究擬利用高壓高溫的方式，來進行快速非等向性濕式矽蝕刻，利用壓力輔助機制，可將蝕刻面的表面張力降低，並增加蝕刻液的氣體溶解度。最後，使氫氣泡附著現象得到有效解決，並增加蝕刻液的質傳效果，可降低蝕刻表面的粗糙度並大幅度地提升蝕刻速率。
在應用方面，本研究將使用高壓高溫輔助蝕刻機制，結合快速的蝕刻速率、良好的表面粗糙度與非機械式攪拌方式等特性，用於製作各式薄膜微結構，達到大幅降低製程時間，並增加製作薄膜微結構之良率。
本研究將以KOH與TMAH溶液為蝕刻液，整合薄膜沉積、微影(lithography)、電漿蝕刻等製程技術來進行研究計劃，並購裝具高壓控制、高溫控制、抗侵蝕及高強度等特色之高壓暨高溫濕式矽蝕刻系統，進而改善矽蝕刻特性。研究中所獲得的最佳參數，將應用於高精度矽微結構與薄膜微結構的製作，以達到批次量產的目的，實現低成本微機電系統的製造與應用技術。

關鍵字

快速非等向性濕式蝕刻 ； 高壓矽蝕刻 ； 濕式蝕刻

並列摘要

Anisotropic wet etching is one of the key technologys for the microstructure fabrication in Micro Electro Mechanical Systems(MEMS). In the study, for improving the roughness quality and etching rate of etched surface, high pressure and high temperature enhanced fast anisotropic etching of mono-crystalline silicon, the methods will be used to evaluate the etching properties of (100) silicon plane in KOH or TMAH solutions. The anisotropic etching parameters will be optimized adequately and employed to fabricate the high precise silicon microstructures.
For the study of batch production, the silicon structures will be formed the metallic mold insert by the electroforming process, and then the molding process, including hot embossing or injection molding, will be applied to produce mass plastic microstructure, and then the low-cost MEMS applications will be realized. Four key techniques will be focused as followed: (1) To setup the apparatus of high pressure and high temperature suitable to anisotropic fast wet etching of single silicon; (2) To build up the optimized fast etching process parameters, (3) To fabricatie the silicon-microstructure and Silicon nitride membrane microstructure.
The results of carrying out project will be predicted to promote the domestic silicon etching technique in MEMS , and also facilitate the international competitive power of the related companies in the market of micro-systems, which have been demonstrated as the highest valued industry in the future.

並列關鍵字

Fast anisotropic etching ； high pressure

參考文獻

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