以多晶矽晶圓之少數載流子 估計太陽能轉換效率

A Study of Estimating Solar Transformity as Functions of Polysilicon Wafer’s Minority Carrier Lifetimes

鄭為太(Wei-Tai Cheng)

指導教授 ： 桑慧敏

國立清華大學/工學院/工業工程與工程管理學系/碩士(2014年)

摘要

在太陽能產業中, 估計太陽能轉換效率是了解太陽能晶碇品質之重要課題。該估計值也會影響太陽能產業製程之配方, 如長晶前原料的配方。已知少數載流子是工廠內可用來量測太陽能電池品質, 進而估計太陽能轉換效率的重要因素。據我們所知, 目前文獻沒有探討這方面的有效公式, 目前國內使用的估計值也有待改善。本研究利用少數載流子相關的資料提出估計太陽能轉換效率之迴歸公式。
其迴歸公式中三個顯著因子為(1) 某晶碇中四個角落的尾端機率平均值, (2) 某晶碇之所有晶棒的少數載流子尾端機率的第四階動差, (3) 同一個晶棒中所有晶片的少數載流子的第四階動差。本文所提出之迴歸公式中三個顯著因子可解釋太陽能轉換效率變異數的88%。

關鍵字

少數載流子 ； 太陽能轉換效率 ； 逐步迴歸 ； 相關係數 ； 迴歸分析

並列摘要

In the solar industry, estimating the solar transferring rate is an important issue because the estimate can be used to understand the quality of a solar crystal ingot. Also, the estimated value greatly influences the manufacture process, such as the material recipes of the crystal ingot in such industry. Minority carrier lifetimes can be used to measure the quality of solar crystal ingot and further to estimate the solar transferring rate. To our knowledge, there does not exist any effectively implementable formula measuring the solar transferring rate as functions of Minority carrier lifetimes.
This research proposes a regression function used to estimate the solar transferring rate as functions of minority carrier’s lifetimes. The proposed three significant factors in the regression function are (1) the average of the tail probability of four corners of a crystal ingot, (2) the fourth moment of the tail probability of all the crystal bars in a crystal ingot, and (3) the fourth moment of carrier lifetimes of all the cells in a same crystal bar. The accuracy of the proposed regression model via the coefficient of determination R-square, the fraction of variances of the response variable (the solar transferring rate) explained by the regression line (via the proposed three factors), is 88%.

並列關鍵字

Minority Carrier Lifetime ； Solar Efficiency ； Stepwise Regression ； Correlation ； Regression Analysis

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