以OES光譜進行ECR-CVD太陽電池用氫化氧化矽薄膜製成分析

Using OES to analyze the hydrogenated silicon oxide film ECR-CVD process for solar cell

謝育霖(Yu-Lin Hsieh)

指導教授 ： 利定東

國立中央大學/工學院/機械工程學系/碩士(2012年)

摘要

本研究利用光放射光譜儀(Optical Emission Spectroscopy，OES)探討電子迴旋共振化學氣相沉積(ECR-CVD)之氫化氧化矽薄膜製程電漿光譜與沉積薄膜特性之關連性。研究中以不同電漿功率、操作壓力、氫稀釋濃度及二氧化碳稀釋濃度等條件，利用光放射光譜儀(OES)探測氫化氧化矽薄膜製程中之關鍵電漿物種Si*(288nm)、SiH*(414nm)、Hβ*(486nm)、O*(604nm)、Hα*(656nm)之光譜強度變化趨勢，並以不參與反應的Ar*(750nm)譜線做為參考基準，計算相對物種濃度變化，對照相同條件所沉積薄膜之光電特性並進行分析研究。
總結實驗結果發現在固定總流量與壓力之條件下，可利用OES之SiH*光譜推測出沉積速率之相對關係；在參與反應之相關物種鍵能均比Si-O鍵能低之條件下，可透過O*光譜推測各實驗薄膜中相對氧含量；透過上述光譜與薄膜特性之對應，建立本系統之相關參數資料庫，將可縮短薄膜製程優化時間。
最後發現氫化氧化非晶矽薄膜在800W 、350℃、5mTorr之工作環境下，分別當CO2/SiH4比值小於0.2與H2/SiH4之比值大於10後薄膜會開始有結晶相的產生。

關鍵字

氫化氧化矽薄膜 ； 電子回旋共振化學氣象沉積 ； 光放射光譜儀

並列摘要

The Optical Emission Spectroscopy (OES) has been used as a diagnostic tool for analyzing the plasma spectrum of Electron Cyclotron Resonance Chemical Vapor Deposition (ECR-CVD) in silicon oxide thin film process. In this study, the correlation between spectrum variation trend and SiOx film properties has been discussed.
The results shown when the total flow rate and working pressure were fixed, the silicon oxide deposition rate could be conjectured by SiH* spectroscopy. Moreover, on the premise that the bond energy of reaction species were lower than Si-O bond, the O* spectroscopy intensity would positive correlation with oxygen content of thin film. Based on the above results, we could develop the database about plasma spectra and film properties, and then the time requirement for silicon oxide process optimization will reduce significantly.
Finally, in 800W, 350°C and 5mTorr, we found the hydrogenated amorphous silicon oxide would transform to the crystalline phase when CO2/SiH4 ratio was less than 0.2 and H2/SiH4 ratio greater than 10.

並列關鍵字

SiOx:H ； OES ； ECR-CVD

參考文獻

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