在本論文中，我們利用有機化學氣相沉積系統成長出氮化鎵/氮化銦鎵多重量子井與氮化鎵塊材的三五族氮化物材料，並利用溝槽式電極的方式製造金半金光檢測器。為了得到高品質的磊晶材料以及延伸檢測波長至較長波長以供不同檢測需求，我們在一開始探討不同的主動層結構對於元件特性之影響，然後討論成長氮化鎵/氮化銦鎵多重量子井的參數，例如多重量子井之銦含量以及量子井對數，最後我們討論不同金屬對於元件特性之影響。並且我們利用一些分析設備來對我們所成長出來的磊晶品質上的分析，而分析的設備包含高解析度X光繞射儀、原子力顯微鏡、掃描式電子顯微鏡以及變溫光激發光分析。具有這種氮化鎵/氮化銦鎵多重量子井金半金光檢測器最後被製造，然後我們將對這些元件做特性上的分析。
這篇論文主要由兩大部分組成的。在第一部分，我們主要是在討論氮化鎵/氮化銦鎵多重量子井主動層結構以及電極結構對於元件特性之影響，並且和一般的氮化鎵塊材上製作出的氮化鎵的金半金光檢測器的特性來做比較，我們發現具有溝槽式電極之元件其在光電特性都有較好的表現，同時發現當使用氮化鎵/氮化銦鎵多重量子井做為元件主動層結構時，由於其結構之高載子遷移率的二維電子氣與溝槽式電極的均勻電場，使得其元件特性明顯優於具溝槽式電極之氮化鎵金半金光檢測器。在三伏特的偏壓下，我們可以發現具有溝槽式電極與氮化鎵/氮化銦鎵多重量子井結構之金半金光檢測器的暗電流、光暗電流比與響應率分別為2.8×10-12 A、5.7×106以及0.72 AW-1，比使用一般的氮化鎵金半金光檢測器所做出來的還要好。
在第二部分，我們主要是在討論改變氮化鎵/氮化銦鎵多重量子井其銦含量與量子井對數對於藍綠光吸收效率之改善與電極金屬對於元件特性之影響。我們嘗試出來當銦含量為35%且量子井對數為13對時，其具有較好的藍綠光吸收效率。我們以高解析度 X 光繞射儀以及變溫光激發光分析此結構具有較低的銦聚集效應與較低的活化能，且其具有較高的主動層磊晶品質與蕭特基能障。同時本論文中也討論不同金屬對於元件特性之影響，在此部分我們發現金屬之導電性與功函數將會影響元件之光電特性與蕭特基能障，其有抑制漏電流的效果，因此使得其元件的特性上得到改善。在三伏特的偏壓且入射光波長為480 nm時，我們可以發現具有溝槽式鉑電極與氮化鎵/氮化銦鎵多重量子井結構之金半金光檢測器的蕭特基能障、暗電流與光暗電流比分別為1.02 eV、2.79×10-13 A以及6.8×103。

In this thesis, the nitride-based GaN/InGaN mulit-quantum-wells (MQWs) and GaN bulk active layer had been grown by metal organic chemical vapor deposition system (MOCVD) and processed with recessed electrodes for metal-semiconductor-metal (MSM) photodetectors (PDs). In order to realize high quality epitaxial layer and extend the absorption region to blue-green region for various applications, the active layer structures, such as GaN/InGaN MQWs and GaN bulk, had been discussed. And then the growth conditions, such as In composition and periods of QWs had been optimized. The effects of various electrodes’ metals on the performance of PDs were also discussed in this thesis. Several analysis techniques, such as X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM) and temperature-dependent photoluminescence (TDPL), had also been performed to characterize the crystal quality of these epitaxial layers. The MSM PDs with GaN/InGaN MQWs active layer and recessed electrodes were then fabricated and characterized.
This thesis is made up of two parts. In the first part, we focused on the GaN/InGaN MQWs active layer and electrode structures. Comparing with the GaN bulk PDs, it was found that the opto-electrical characteristics of the devices with recessed electrodes were better than those without. It was also found that the characteristics of the devices with GaN/InGaN MQWs active layer structure were better, because of the high mobility of two-dimensional electron gas (2DEG) at the hetero-junction and the uniform electric field resulted from the geometry of electrodes in the active layer. At 3 V, the dark current, photo to dark current ratio and the responsivity were 2.8×10-12 A, 5.7×106 and 0.72 AW-1, respectively.
In the second part, we focused on the In compositions and periods of QWs in the GaN/InGN MQWs for blue-green region absorption and the effects of various electrodes’ metals. It was found that the optimized In composition and the period are 35% and 13, respectively. According to HRXRD and TDPL, this optimized structure had smaller In localization effect, smaller activation energy, better quality and higher Schottky barrier height. At the last of this thesis, different electrodes’ metals for the MSM MQW PDs had been discussed. In this part, it was found that the conductivities and the work functions of the electrodes’ metals would affect the opto-electrical characteristics and Schottky barrier height to reduce the leakage current and hence improve the properties of the devices. At 3 V, the Schottky barrier height, dark current and photo to dark current ratio of the devices with Pt-recessed-electrodes and GaN/In0.35Ga0.65N MQWs active layer structure were 1.02 eV, 2.79×10-13 A and 6.8×103, respectively.

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