氮化鎵金屬-半導體-金屬光偵測器之製程與光電特性

Abstract

中文摘要 柵狀結構紫外光的金屬-半導體-金屬光偵測器已經成功的製作在無摻雜氮化鎵基板上。利用L-EDIT軟體設計出可製作出各種不同條件的金屬-半導體-金屬（MSM）光偵測器元件的三道光罩圖形，其中包含了四種不同的電極寬度､五種間距､不同的電極長度､以及有無氧化層保護。在製程上，分別蒸鍍白金､鎳/金､白金/金三種不同的金屬，並分別給予適當溫度的熱退火處理。元件特性量測方面，針對各種不同條件的MSM光偵測器元件之照射光源波長的響應(光譜響應)､以及外加偏壓的響應(直流響應)加以比較與分析。白金/氮化鎵MSM表現出最低的暗電流。其光譜響應範圍在270~370 nm，在360 nm 處有響應最大值1.8 mA/W。

Abstract Interdigitated ultraviolet metal-semiconductor-metal photodetectors were successfully fabricated on undoped-GaN wafers. We fabricated many kinds MSM photodetectors with finger width = 3, 4, 5, 8 μm, finger spacing width = 2, 3, 4, 5, 8 μm, and with or without oxidation. In process, Pt, Ni/Au, Pt/Au metals are deposited on individual wafers with annealing. We measured the photo responsivity and current-voltage to characterize MSM photodetectors. The Pt/GaN MSM photodetectors gives the lowest dark current and its range of responsivity versus wavelength is 270~370 nm. The maximum responsivity is 1.8 mA/W at 360 nm.