臺灣博碩士論文加值系統

本論文探討利用準分子雷射退火(Excimer Laser Annealing ,ELA)技術在玻璃基板成長的低溫多晶矽薄膜(LTPS)上研製MIS蕭特基二極體式低成本太陽電池,其中I層係採用二氧化鈦(TiO2)薄膜。吾人利用FE-SEM、AFM、XRD、Spectra Pro500及霍爾量測等來分析LTPS及TiO2薄膜的結構及光電特性，再利用HP4145量測光暗電流增益、Jsc、Voc、Fill Factor及Efficiency等重要參數。
實驗結果證明LTPS薄膜經由PH3 及B2H6電漿助長化學氣相沉積系統(PECVD)氫化處理確實能改善薄膜的電子特性，其中B2H6電漿掺雜比PH3電漿掺雜對改善光特性較顯著。此外,利用射頻磁控式(Radio-Frequency Sputtering System)電漿鍍膜法成長1.5nm TiO2 薄膜並經退火(annealing)處理10分鐘，能使薄膜更緻密化及減少薄膜缺陷(defect);元件的光暗電流增益也從原先的32增加到120。因此吾人利用這結構來作為低成本薄膜太陽能電池。其特性為;使用髮夾狀金屬電極(間距=200μm) 之 MIS Solar Cell, VOC=14.5mV、ISC=0.226mA、FF=0.82、η=0.05% ;而指叉狀金屬電極(間距=100μm)之MIS Solar Cell, Voc=230mV、Isc=1.32mA、FF=0.576、η=3.34%。如指叉狀金屬電極間距能縮到1μm以下則效率可望提高到5〜6%。

This thesis reported to fabricate Metal-Insulator-Semiconductor (MIS) Schottky diode-type low cost solar cell with excimer laser annealed (ELA) low temperature poly-silicon (LTPS) on glass substrate. In the cell, the TiO2 thin film was employed as insulator layer. We investigated physical and optical characteristics of the LTPS and TiO2 thin films by FE-SEM, AFM, Hall measurement, XRD, and Spectra Pro500.In addition, the HP4145 was employed for measurement of current gain, Jsc, Voc, fill factor and efficiency.
The electrical characteristics of the LTPS thin films were improved by B2H6 and PH3 plasma annealing with PECVD, and found the B2H6 plasma treatment could improve a better optical characteristic than that with PH3 plasma annealing. After plasma annealing, TiO2 thin films were grown on LTPS thin films by radio-frequency sputtering. Then annealed the TiO2 thin film for 10 minutes to improve the quality of the thin film, consequently, the optical gain was raised from 32 to 120. The typical performances of the solar cell with a comb contact electrode (space=200μm), are conversion efficiency =0.05%, Isc= 0.226mA, Voc= 14.5mV, FF =0.82. However, the plasma annealing was changed to a finger structure (space=100μm), the performances were improved to conversion efficiency =3.34%, Isc=1.32 mA, Voc= 230mV, FF =0.576. It is expected the conversion efficiency can be raised to 5〜6%,if the space of the finger contact can be reduced to less than 1μm.

第一章 導論 1
1-1 前言 1
1-2 低溫多晶矽成長技術簡介 3
1-3 論文架構 5
第二章 太陽電池與元件原理 6
2-1 太陽電池簡介 6
2-1-1 太陽電池的原理 6
2-1-2 太陽光譜 7
2-1-3 太陽電池之等效電路 8
2-1-4 太陽電池之效率量測 9
2-2 元件基礎理論 12
第三章 成長系統、量測儀器原理簡介與元件製作 15
3-1 成長儀器系統 15
3-1-1 電漿助長化學氣相沉積系統(PECVD) 15
3-1-2 真空熱蒸著系統(Thermal Vacuum Evaporation System) 16
3-1-3 射頻磁控濺鍍系統(Radio-Frequency Sputtering System) 17
3-1-4 退火系統（Annealing System） 19
3-2量测儀器及原理簡介 19
3-2-1 掃描式電子顯微鏡 (FE-SEM) 19
3-2-2 原子力顯微鏡 (AFM) 20
3-2-3 X光繞射儀 (X-ray Diffraction, XRD) 20
3-2-4 光譜效應 (Photo Response) 21
3-2-5 霍爾量測 (Hall measurement) 21
3-2-6 Spectra Pro-500 21
3-2-7 HP4145B 22
3-3 元件之製作程序 23
第四章 結果與討論 25
4-1 電漿摻雜處理對低溫多晶矽薄膜的影響 25
4-2 二氧化鈦薄膜材料分析 28
4-3 不同摻雜與絕緣層對元件的影響 29
4-4太陽電池I-V特性曲線 31
第五章 結論與未來展望 32
5-1 結論 32
5-2 未來展望 32
參考文獻 34

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