電化學蝕刻輔以633nm氦氖雷射之光鈍化現象

The Light-Passivation Effect of the 633 nm He-Ne Laser in the Electrochemical Etching Process

張昕錡(HSIN-CHI Chang)

指導教授 ： 李天錫

國立中央大學/工學院/光機電工程研究所/碩士(2014年)

摘要

在1985年時科學家Uhlir正在對矽基板進行電解拋光，意外發現表面有一層黑色薄膜，此即為多孔矽。而多孔矽的形成於P型矽時需仰賴電化學方式並於陽極反應中產生電洞使氫氟酸電解液與矽表面產生化學溶解反應，若無施加電壓則氫氟酸電解液與矽晶圓並不會發生化學溶解反應。
由於多孔矽具有許多化學性質因此廣泛應用在各個領域，包括半導體產業、微機電系統太陽能電池、光電元件、感測器，也因而對於多孔矽的製作與研究越來越廣泛，尤其是關於如何有效提升蝕刻效率、縮短製程時間、降低製程成本的方面，因此本研究以雷射為照射在P型矽會有如何現象為前提來研究，分別進行雷射功率為2.0mW、1.0mW、0.5mW，定電流為100mA蝕刻時間為30分鐘之電化學蝕刻實驗，利用場發射掃描式電子顯微鏡加以分析試片，並以阿瑞尼斯方程式計算活化能來說明實驗結果。

關鍵字

電化學蝕刻 ； 光鈍化 ； 633nm氦氖雷射

並列摘要

In the 1985, scientist Uhlir firstly discovered the layer with porous when he working electrolytic polishing on the surface of silicon substrate. The process of the porous surface on P-type silicon relied on the electrochemical methods such as the conformation of holes in the anode reaction and the chemical reaction between hydrofluoric acid electrolyte and the silicon surface. While the reaction between hydrofluoric acid electrolyte and the silicon surface need to apply the appropriate voltage to trigger off the electrochemical reaction.
For the variously electrochemical properties of porous silicon, it is widely used in many fields, including the semiconductor industry, micro-electromechanical systems, solar cells, photovoltaic components and sensors…etc. Particularly, how to improve the efficiency of the etching, shorten the process time and reduce the cost of process were attended. This study focus on the experiments for P-type silicon that using the irradiation of laser power with 0.5mW, 1.0mW, 2.0mW, respectively, and the given current was 100mA for 30 minutes of etching time. The wafers with electrochemical etching were scanned on the field emission scanning electron microscope (FE-SEM) to analyze the specimens, and explain the experimental results for the activation energy equation by Arrhenius.

參考文獻

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[28] 朱維屏、林天財、劉時郡、劉定杰、張慎周、劉建惟，「離子植入技術製作單晶矽太陽能電池之光電特性研究」，2006台灣鍍膜科技協會年會，崑山科技大學，台南市，2006年。

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