摘要: | 科技的發展帶來能源耗竭的問題,太陽能電池為未來的替代性能源之一,目前太陽能電池的成本較其他能源昂貴,所以太陽電池技術的發展有三個主要準則:效率要高、生產成本要低、可靠度及穩定度要好。為了降低成本,確保電池的良率與使用壽命,使得近年來太陽能電池的量測扮演著很重要的角色,光激發光則為近年迅速發展的技術。本文使用光激發光影像技術,分別量測額外載子生命期與串聯電阻,由於一般使用光激發光量測時,入射光與試片間的角度傾斜,使得入射光不均勻,造成量測的誤差,本研究提出Pixel-by-Pixel的演算法,解決了入射光不均勻所造成的誤差。計算單晶矽太陽能電池時,平均額外載子生命期約為1.0´10-4秒,將量測時的標準差代入近算,可知這個方法的誤差為3.4´10-6秒,大約3.4%。為驗證這個方法的正確性,分別使用平均入射光強度0.069 W/cm2、0.081 W/cm2所量到的額外載子生命期,相除的結果平均值為1.0958,標準差為0.1366。我們也將這個方法應用在多晶矽太陽能電池,量測出的額外載子生命期約為2.0´10-5秒。 在計算串聯電阻方面,一般假設電流均勻分佈,本研究連結了螢光影像與電流的關係,可測量電流的分佈。此外,本研究提出新的量測方法,以0.45 W/cm2做為強光照,分別以0.11 W/cm2、0.09 W/cm2與0.068 W/cm2三種不同的入射光強度做為弱光照,量測串聯電阻後,每個像素相除的平均值分別為1.046、1.01和1.046,標準差分別為0.18、0.23與0.27,大致為1,證明了此法的正確性,經推導發現本研究所提出的方法為計算串聯電阻的通解,而一般的方法則是在計算串聯電阻時,特定條件下(入射光很弱,使得串聯電壓與端電壓相比可略)的特解。 Technological developments brought up the issue of energy depletion, as the result, solar cells become one of alternative sources of energy. The cost of solar cell is relatively expensive compared to other energy sources. Therefore, solar technology development needs to meet three main criteria, higher efficiency, lower production costs, reliability and stability. In order to reduce costs, it is necessary to ensure the service life and the quality by using solar cells measurement. As the result, photoluminescence has become one of the fastest developing technologies for solar cells measurement in recent years. That photoluminescence technology produces when measuring excess carrier life time and series resistance. Pixel-by-pixel algorithm was developed to obtain solar cell excess carrier lifetime. This method handles the solar cell photoluminescence imagine signal excited by non-uniformly illumination. We obtained the excess carrier lifetime over the entire measured area about 1.0?10-4 sec with uncertainty about 3.4?10-6 sec in single crystalline silicon solar cell. We choose two incident light intensity at 0.069 W/cm2 and 0.081 W/cm2 obtained almost identical excess carrier lifetime distribution. By dividing the excess carrier lifetime pixel-by-pixel of these two set of data, we obtained average value of the ratio is about 1.10?0.14 which confirm the validation of this algorithm. We also use this method on poly crystalline silicon solar cell and obtained the excess carrier lifetime over the entire measured area about 2.0?10-5 sec. In series resistance, typically assume that the current is uniform distribution. This article links the photoluminescence and current relationship, that current distribution become measurable. In addition, the study proposes a new measurement method to calculate series resistance, and confirm the validity of this method by measure same solar cell on different incident light intensity. We measuring series resistance use the 0.45 W/cm2 as a strong light, 0.11 W/cm2, 0.09 W/cm2 and 0.068W/cm2 respectively as a weak light. Divide the value of each pixel we get mean value respectively is 1.046?0.18, 1.01?0.23 and 1.046? 0.27, which confirm the validity of this method. We also find that the method is the general solutions for calculate the series resistance. Typically method is the solutions which under the specific conditions (when the incident light is so week that compared to terminal voltage, series voltage can be ignored). |