碳化矽是唯一其原生氧化層為二氧化矽的化合物半導體，其優異的物性及電性在製程上便能與矽來做競爭並且應用於積體電路中。碳化矽在自然界幾乎不存在，因此實驗製備上通常需要於高溫環境中成長，或者高溫熱處理才能獲得特性良好的薄膜。為了避免高溫熱處理步驟，本論文主要是利用電漿增強式化學氣相沉積系統於低溫下沉積碳化矽薄膜作為通道層之p型空乏式金氧半場效電晶體，除了探討利用硫化、氫氣電漿等表面處理的改善效用外，也運用二氧化碳雷射輔助電漿增強式化學氣相沉積的技術，探討改變有無雷射輔助條件成長通道層對元件特性的影響。
比較未經雷射輔助成長且未經表面處理通道層厚度10nm之元件、未經雷射輔助成長且經表面硫化處理通道層厚度10nm之元件、未經雷射輔助成長且經表面氫氣電漿處理通道層厚度10nm之元件、經雷射60W輔助成長且未經表面處理通道層厚度10nm之元件、經雷射60W輔助成長且未經表面處理通道層厚度6nm之元件、經雷射60W輔助成長且經表面氫氣電漿處理通道層厚度10nm之元件及經雷射60W輔助成長且經表面氫氣電漿處理通道層厚度6nm之元件等7種情形。在電流電壓特性方面，可以發現到，當閘極電壓為 0V，汲極電壓為−35V時，其汲極電流分別為−0.208μA/mm、−0.209μA/mm、−0.328μA/mm、−5.956μA/mm、−1.189μA/mm、−8.775μA/mm、−1.198μA/mm。轉導值最大值分別為27nS/mm、28nS/mm、69nS/mm、204nS/mm、165nS/mm、501nS/mm、187nS/mm。在閘極電壓−40V時，其閘極漏電流分別為79.08×10-12A、62.17×10-12A、35.41×10-12A、5.18×10-12A、13.31×10-12A、6.15×10-12A、12.74×10-12A。由結果顯示經由雷射輔助成長的元件由於薄膜品質改善，其元件電特性會比只利用表面處理降低缺陷密度來得更好。

Silicon-Carbide (SiC) is the only compound semiconductor which native oxide layer is silicon dioxide. Due to its terrific physical and electrical properties, it can compete with silicon in applications of integrated circuits. However, because SiC barely exists in Nature, the deposited SiC films usually have to be deposited or annealed in high temperature for obtaining high performances. To avoid processing in high temperature circumstances, in this thesis, the main purpose is to deposit SiC films in low temperature as channel layers of p-type depletion-mode metal-oxide-semiconductor field-effect transistors by using the plasma enhanced chemical vapor deposition system (PECVD). In addition to investigating the improving effects on surface treatments such as sulfide treatment and hydrogen plasma treatment, we also investigate the effects on the device fabricated with or without laser assistance by using laser-assisted plasma-enhanced chemical vapor deposition (LAPECVD) technique.
In this thesis, we compare with device characteristics in seven processing conditions. The first condition is the device without laser assistance and without surface treatment which thickness is 10nm. The second condition is the device without laser assistance and with sulfide treatment which thickness is 10nm. The third condition is the device without laser assistance and with hydrogen plasma treatment which thickness is 10nm. The fourth condition is the device with laser 60W assistance and without surface treatment which thickness is 10nm. The fifth condition is the device with laser 60W assistance and without surface treatment which thickness is 6nm. The sixth condition is the device with laser 60W assistance and with hydrogen plasma treatment which thickness is 10nm. The last condition is the device with laser 60W assistance and with hydrogen plasma treatment which thickness is 6nm.According to the above conditions, the drain-source current at VGS=0V and VDS=−35V is −0.208μA/mm, −0.209μA/mm, −0.328μA/mm, −5.956μA/mm, −1.189μA/mm, −8.775μA/mm and −1.198μA/mm, respectively. The maximum value of extrinsic transconductance is 27nS/mm, 28nS/mm, 69nS/mm, 204nS/mm , 165nS/mm, 501nS/mm and 187nS/mm, respectively. At VGS =−40V, the gate leakage current is 79.08×10-12A, 62.17×10-12A, 35.41×10-12A, 5.18×10-12A , 13.31×10-12A, 6.15×10-12A and 12.74×10-12A, respectively. The results show that because the film quality is improved by laser assistance, the device electrical characteristics is better than that improved by decreasing interface state density by surface treatment.

第一章 緒論
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第二章 背景理論
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第三章 元件製程
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第四章 結果與討論
[1]劉宗達(Tzung-Da Liou), “Investigation of silicon-based thin-film solar cell grown by laser-assisted plasma enhanced chemical vapor deposition,” 成大微電子所碩士論文, 2010.
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