以深紫外線輔助對N 型氮化鎵做光電化學濕式蝕刻

Deep Ultraviolet-Assisted Photo-Electro-Chemical Wet Etching of N-Type GaN

本文採用光電化學蝕刻的方式，實施了對n 型氮化鎵半導體材料之濕式蝕刻。提出以波長為237nm 之深紫外線，光功率密度約為17.3mw/cm2 之氚氣燈為輔助光源，使用pH=12.6~12.9之氫氧化鉀（KOH）及pH=1.09~1.39 之磷酸（H3PO4）做為電解溶液。並獲得了於pH=1.09 之磷酸電解溶液下，其蝕刻速率大於240nm/min。本文報導了蝕刻速率及光電流與電解溶液濃度之間的關聯性。 In this research, room-temperature photo-electro-chemical etching (PEC) of n-type GaN films by using potassium hydroxide (KOH), pH=12.60-12.90, and phosphorus acid (H3PO4), pH=1.09-1.39, in a stirred solution under deuterium-lamp illumination was achieved. The process provides anisotropic etching profiles and high etching rates of more than 240 nm/min at moderate light intensities of ~17.3 mW/cm2 with 237 nm in an H3PO4 (pH=1.09) solution. The etching rate and photocurrents are characterized at various concentrations of stirred solutions.