在 N 型碳化矽電化學蝕刻中，主要是利用電子作為載流子來進行，而陽極氧化則是需要電洞來進行。因此使用 P 型矽與 N 型碳化矽的接面形成 PN 接面來進行蝕刻。並且通過加入金屬在 P-N 接面中可以形成兩個金屬及半導體接面產生蕭特基能障來進一步降低接面電壓來使電洞快速移動，提升蝕刻速度。本研究將比較銅與鋁兩種不同的金屬形成的 P-M-N 接面對於蝕刻的影響，本研究使用蝕刻液為氫氟酸（55%）：酒精（95%）=1:1 進行混合，使用 100mA、300mA、500mA 蝕刻 60 分鐘，並使用掃描式電子顯微鏡（SEM）對試片進行分析，發現利用鋁形成的蕭特基接面進行的輔助刻， 其加速蝕刻效果非常好，並且對於試片的結構影響極低，並且透過銅與鋁的 PMN 接面與 PN 接面比較，推測不同摻雜度的 P 型矽與金屬有一個最佳的蕭特基能障大小組合。;In the electrochemical etching of n-type silicon carbide (SiC), electrons are primarily used as carriers, whereas anodic oxidation requires holes. Therefore, a PN junction is formed by using p-type silicon and n-type SiC for etching. By incorporating metal into the PN junction, two metal-semiconductor junctions can be formed, creating Schottky barriers that further reduce the junction voltage, facilitating the rapid movement of holes and enhancing the etching rate.This study compares the effects of PMN junctions formed by copper and aluminum on the etching process. The etching solution used is a mixture of hydrofluoric acid (55%) and alcohol (95%) in a 1:1 ratio. Etching is performed at currents of 100mA, 300mA, and 500mA for 60 minutes. The samples are analyzed using a scanning electron microscope (SEM). The results indicate that the assisted etching with Schottky junctions formed by aluminum significantly accelerates the etching process while having minimal impact on the sample′s structure. Furthermore, by comparing PMN junctions formed with copper and aluminum with PN junctions, it is inferred that there is an optimal Schottky barrier combination for different doping levels of p-type silicon and metal.
