| dc.description.abstract | 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).
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