在對於 n 型碳化矽電化學蝕刻時，由於其主要載流子為電子，而陽極氧 化需要電洞才能對 n 型碳化矽進行蝕刻，所以使用 p 型矽形成 pn 接面來輔 助碳化矽的蝕刻。本研究在 pn 接面當中加入銅箔，形成兩個金屬-半導體接 面通過產生蕭特基能障來降低 pn 接面之間的接面電壓使電洞可以快速的移 動到碳化矽表面進行蝕刻，大幅提升蝕刻速度。 本研究使用蝕刻液為氫氟酸(47%):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)、高解析雙束型聚焦離子束系統(FIB)、穿透式電子顯微鏡 (TEM)、光致發光光譜儀(PL)對試片進行進一步分析，發現在使用 p+ 矽與銅箔同時輔助蝕刻時，加速蝕刻效果更好，並且加入銅箔對於結構並無 影響。 ;In the electrochemical etching of n-type silicon carbide, because the main carriers are electrons, and anodic oxidation requires holes to etch n-type silicon carbide, so p-type silicon is used to form a pn junction to assist the etching of silicon carbide.In this study, copper foil is added to the pn junction to form two metal-semiconductor junctions. By creating a Schottky energy barrier to reduce the junction voltage between the pn junctions, the holes can quickly move to the silicon carbide surface for further processing. Etching, greatly increasing the etching speed. In this study, the etching solution was mixed with hydrofluoric acid (47%): alcohol (95%) = 1:1, etched at 100mA, 300mA, and 500mA for 60 minutes, and scanned electron microscope (SEM), high-resolution dual-beam Focused ion beam system (FIB), transmission electron microscope (TEM), and photoluminescence spectrometer (PL) further analyzed the test piece, and found that when p+ silicon and copper foil are used to assist etching at the same time, the acceleration time is better. , and the addition of copper foil has no effect on the structure.
