本論文針對碳化矽磊晶層中存在之缺陷進行表徵及生長機制的探討，並透過製作不同尺寸大小之蕭特基二極體，藉由元件電性量測後再對其進行缺陷的反向工程分析，微觀探討元件磊晶層中各種型態缺陷對元件特性之影響，並歸納其相關性，最終以建立碳化矽晶片缺陷標準化評估模式為目標。
首先建立各種分析手法來表徵不同類型的碳化矽缺陷，包括以500℃熔融氫氧化鉀蝕刻試片3分鐘後可明辨出磊晶層表面的貫穿螺旋差排(TSD)、貫穿刃差排(TED)和極少數之基底面差排缺陷；以陰極發光光譜辨識出發光波長在500 nm的堆積缺陷；另外使用微分干涉顯微鏡輔以拉曼光譜儀觀測到磊晶層表面之三角形缺陷可能是由磊晶過程中氣相混入的立方晶碳化矽成核點處沿著磊晶方向之異常成長所造成。
其次在製作成蕭特基二極體(SBDs)的實驗發現，在固定逆向偏壓為200 V作用下，隨著TSD與TED缺陷密度總和由1600 cm-2增大到4800 cm-2時，二極體的漏電流從3.4×10-7 A/cm2增加到1×10-6 A/cm2，此時量測到的元件蕭基能障由1.62 eV至1.28 V的下降呼應此一漏電流的上升。此外又發現，二極體的崩潰電壓與TSD密度大小並無相關連，但隨TED密度由1600 cm-2增大至4600 cm-2時明顯地從280 V下降至100 V。我們推測這與TED缺陷結構具有比TSD較短的穿隧通道距離有關。

In this study, reverse engineering analysis of the crystal defects in the active layer of 4H-SiC Schottky diode after electrical behavior measurement was performed to explore the effects of various types of defects on the device.
First of all, we established various analytical methods to characterize various types of SiC defects. Molten potassium hydroxide technique was used to etch the sample at 500℃ for 3 min to distinguish structural defects like threading screw dislocation (TSD), threading edge dislocation (TED), and basal plane dislocation. Cathodoluminescence spectroscopy was used to identify stacking fault which emits light at wavelength of 500 nm. In addition, through differential interference optical microscopy together with Raman spectroscopy, the formation of triangular defects on the wafer surface is most plausibly attributable to the 3C inclusion during epitaxial growth.
Secondly, at a fixed reverse bias of 200V, the leakage current of the 4H-SiC Schottky diode increased from 3.4×10-7 A/cm2 to 1×10-6 A/cm2 as the total defect density of TSD and TED increased from 1600 cm-2 to 4800 cm-2, while the measured Schottky barrier, reducing from 1.62 eV to 1.28 eV, is responsive to the increasing of this leakage current. Moreover, in contrary to the irreverence of the breakdown voltage with respect to TSD density, the breakdown voltage dropped significantly from 280 V to 100 V with increasing TED density from 1600 cm-2 to 4600 cm-2. Shorter tunneling distance of TED than TSD for the carriers to penetrate through the active layer of the diode may be explainable to these phenomena.

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