由於目前的P-型半導體的阻抗仍大，電流無法均勻的分佈，以致於需要在P-型半導體上鍍上一層透明導電層，協助電流的分佈，但在光偵測器元件方面，透明導電層卻也同時吸收了部分的入射光，導致光偵測器元件的特性表現下降。
本論文即在探討應用不同材料與不同結構的透明導電層，在氮化鎵系列PIN紫外光光偵測器上的特性表現，使用的材料分為Ni/Au與銦氧化錫（ITO），結構分為平面式與網狀式，而氮化鎵系列PIN紫外光光偵測器的磊晶結構，分為氮化鎵、氮化鋁鎵與具視窗層的氮化鋁鎵等三種，主要比較的元件特性有暗電流、光電流、光響應度與可見光鑑別率。
在三種磊晶架構中，無論是Ni/Au或是ITO，網狀式的透明導電層的應用均能有效的提昇光響應度且不影響暗電流與可見光鑑別率的表現，只是在光響應度的提昇量方面我們發現與透明導電層的穿透率、元件截止波長與視窗層結構運用有關。例如透明導電層穿透率較差的Ni/Au元件，光響應度的提昇量較多，而截止波長在335nm的元件光響應度的提昇量也較多。
在紫外光光偵測器的應用方面，紫外光波段B（320nm~280nm）與波段C（280nm以下）的應用是最多的，但透明導電層的穿透率表現卻是最差的，因此網狀透明導電層應用在這些波段時光響應度的提昇也會較多。

Due to the high resistance of P-type semiconductor, We have to deposit a Transparent Conduct Layer (TCL) as a Current Spreading Layer and a Electrode at the same time. However, TCL absorbs some power from the incident light that reduces the performance of photo-detectors（PDs）. Therefore, the aim of this article attempts to explore how mesh electrode increases the responsivity of PD by reducing the absorbing power of TCL.
In this experiment, GaN、AlGaN and AlGaN with window Layer GaN-based PIN wafer were prepared. Then we deposited Ni/Au and ITO as TCLs. Finally, we made TCLs into Planar and Mesh structures.
Results of this study showed mesh TCL raises the responsivity of PDs. Although the quantity of improvement on responsivity is related to the transmittance of TCLs and the cut-off wavelength of PDs, We still have up to 24% raise on AlGaN PDs. To conclude, since transmittance of TCLs is not so well in wavelength UV-B（320nm~280nm） and UV-C（below 280nm）, applying of mesh TCLs will get better improvement on responsivity.

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