為因應市場需求，蝕刻技術的發展越來越多元。近幾年來有學者發展出各式不同的新型異向性蝕刻技術，如金屬輔助化學蝕刻（Metal-assisted chemical etching）等。為能了解相關原理、技術，有效發揮金屬輔助化學蝕刻製程特性與其優點最佳化，本研究改變蝕刻製程條件，如過錳酸鉀和硫酸濃度與溫度，探討金屬輔助化學蝕刻的反應機制，並觀察基材受到化學蝕刻作用所形成的表面形貌。實驗結果顯示無鍍金之砷化鎵基板被過錳酸鉀分子氧化變成離子的狀態。在鍍金之砷化鎵基板上，經高溫熱處理後會產生金屬輔助化學蝕刻作用。而經低溫處理金顆粒，則扮演遮罩的角色。在未經熱處理的砷化鎵基板，發現金屬輔助化學蝕刻的反應，只會發生在半導體與金屬的界面上。透過改變製程參數的實驗可獲得各種表面形貌，加以整理分析後能更清楚掌握砷化鎵之金屬輔助化學蝕刻的反應機制。

In response to the high demand for the market applications, the development of etching technology has become more diverse. In recent years, various new etching techniques for the anisotropic etching had been developed, such as the metal-assisted chemical etching. In this study, the reaction mechanism of metal-assisted chemical etching is investigated by altering the etching conditions, such as the temperature and the concentrations of potassium permanganate and sulfuric acid. From the experimental results, it shows that the gallium arsenide without gold-coated would be ionized by the potassium permanganate. Under an annealing temperature of 400°C with gold-coated, the reactions of the metal-assisted chemical etching emerge in the gallium arsenide substrate. However, at a low temperature condition the deposited gold might play a role of a resist-mask. Without a thermal annealing treatment, it is found that the reaction of metal-assisted chemical etching occurs only at the interface between the semiconductor substrate and the metal particle. Based on these experiment observations under different etching conditions, the etching mechanisms of the metal-assisted chemical etching are revealed to help in understanding and controlling this technology.