臺灣博碩士論文加值系統

本論文採用電漿增強式化學氣相沉積系統(plasma-enhanced chemical vapor deposition, 13.56 MHz PECVD) 搭配脈波調變電漿 (pulse-wave modulation plasma) 及氫稀釋(Hydrogen dilution: R)兩種技術製作本質氫化非晶矽(a-Si:H)薄膜及a-Si:H p-i-n 太陽能電池。本質 a-Si:H 薄膜的光學特性包含介電系數(1:實部、2:虛部)、折射率(n)、消光係數(k)、吸收係數()及光學能隙(Eg)由橢圓偏光儀測量及模擬分析獲得。a-Si:H p-i-n 太陽電池的暗電流-電壓(dark I-V)、光電流-電壓(photo I-V)及外部量子轉換效率(QE)以 I-V 及 QE 測量儀測量及分析。
本研究選用脈波調變電漿的電漿開啟時間(ton)為 5 及 10 ms、電漿關閉時間 (toff)為 1、 5、10、20 及 30 ms、脈波周期數固定為 240000 次及氫稀釋比( R = H2/SiH4)為R = 5 (R5)及R = 10 (R10)製作本質層 a-Si:H 薄膜及 p-i-n 太陽電池。
變化氫稀釋比、ton 及 toff所製作本質層 a-Si:H 薄膜的介電係數、 折射率、吸收係數及光學能隙僅有最大約 4.4 % 的變化，這些結果顯示薄膜的光學特性變化不大。
將本質 a-Si:H 單層膜製作於 a-Si:H p-i-n 太陽能電池。電池的Voc 及Jsc變化率小於6 % ，但FF變化率可達8 ~ 11 % ，效率的變化率約為 11 ~ 18 % ，影響太陽電池效率的最大的變因為 FF。
本質 a-Si:H 薄膜光學特性的小變化率無法對應太陽電池效率的大變化率。改變電池的電學特性應為薄膜致密性以外之原因。以 FF 的高衰減率( 8~11 % )推論原因為氧汙染。較長的 toff 時間使較多的氧雜質進入薄膜。在 p/i 介面加入以toff 較短時間沈積的低氧含量之緩衝 i 層証實可以提升電池的FF及效率。
本研究製作之 a-Si:H p-i-n 太陽能電池以 R5、ton = 10 ms 及 toff = 1 ms 有最高效率為 7.12 %、FF 為 68 % 、Jsc 為 12.53 mA/cm2、Voc 為 0.84 V。

In this thesis, intrinsic hydrogenated amorphous silicon (a-Si:H) thin films i-layers and p-i-n solar cells were fabricated by 13.56 MHz plasma-enhanced chemical vapor deposition (PECVD) with pulse-wave modulation plasma and hydrogen dilution (R = H2/SiH4) methods. The optical properties of dielectric constants (real part: 1 and imaginary part: 2), refractive index (n), extinction coefficient (k), absorption coefficient () and optical energy gap (Eg) of the a-Si:H i layers were measured by spectroscopic ellipsometry (SE). The dark current-voltage (I-V), photo I-V and quantum efficiency (QE) of the a-Si:H p-i-n solar cells were measured by I-V and QE instruments
The plasma turn-on time (ton), plasma turn-off time (toff), and the periods of the pulsed-wave plasma was 5 and 10 ms, 1, 5, 10, 20, and 30 ms, and 240000 cycles, respectively. The R ratio was 5 and 10.
Modulation R, ton and toff to fabricated a-Si:H i-layers, the variation of  , n,  , and Eg was less than approximately 4.4 %, which indicated that the optical properties of the films were no significantly changed. However, using these a-Si:H i-layers for p-i-n solar cells, the variation of open-circuit voltage (Voc), short-circuit density (Jsc) was within 6 %, and the variation of fill factor (FF) was much higher up to 8 to 11 %. The variation of the energy efficiency was 11 ~ 18%. The most important factor to reduce the efficiency was FF.
The small variation of the optical properties of a-Si:H i-layer could not correspond to the large variation of the I-V characteristics. The large variation of FF indicated that the possible reason for reduction of energy efficiency was due to oxygen contamination. Inserting a low oxygen contamination a-Si:H i-layer deposited by short toff time at the p/i interface could improve FF and  of the solar cell.
In this study, the highest efficiency solar cell was fabricated by R = 5, ton = 10 ms, toff = 1 ms, and the , FF, Jsc and Voc was 7.12 %, 68 %, 12.53 mA/cm2 and 0.84 V, respectively.

誌謝 ii
摘要 iii
Abstract iv
目錄 v
圖目錄 vii
表目錄 x
第一章 緒論 1
1.1 前言 1
1.2氫化非晶矽薄膜太陽電池簡介 1
1.3 研究動機與目的 2
1.4 論文架構 3
第二章 文獻探討 4
第三章 研究方法 9
3.1 實驗流程 9
3.1.1 薄膜製程 9
3.1.2 製程設備 9
3.1.3 基板清洗方式 10
3.1.4 背景真空抽氣程序 11
3.2量測儀器 11
3.2.1 光學量測 11
3.2.2 電性量測 12
3.2.3 光譜響應特性量測 14
3.2.4結構特性量測 14
3.3實驗參數設計 16
3.3.1 a-Si:H單層膜製作與量測 16
3.3.2 a-Si:H薄膜實驗參數設計 16
3.3.3 a-Si:H p-i-n太陽電池製作與量測 18
3.3.4 a-Si:H p-i-n太陽電池實驗參數設計 19
3.3.5氫化非晶矽(a-Si:H)薄膜太陽電池實驗參數設定 21
3.3.6 針對氧汙染之a-Si:H p-i-n太陽電池實驗參數設計 23
第四章 結果與討論 24
4.1脈波電漿 ton = 5/10 ，toff = 1/5/10/20/30，氫稀釋比R5/R10之a-Si:H本質層薄膜之光學特性分析與之探討 24
4.1.1 SE量測結果與分析 24
4.2以脈波電漿之氫稀釋比R5、ton=5/10、toff=1/10/30製作本質層對a-Si:H p-i-n 太陽電池之特性分析與探討 37
4.2.1太陽電池之特性與探討 37
4.3以脈波電漿之氫稀釋比R10、ton=5/10、toff=1/10/30製作本質層對a-Si:H p-i-n 太陽電池之特性分析與探討 41
4.3.1太陽電池之特性與探討 41
4.4 氧汙染對太陽電池之特性分析與探討 46
4.4.1氧濃度分析 46
4.4.2 a-Si:H太陽電池特性分析與探討 47
第五章 結論 51
第六章 未來工作 52
參考文獻 53

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