Because crystalline silicon thin film （CSiTF） solar cells possess the advantages of crystalline silicon solar cells such as high ef- ficiency and stable performance and those of thin film solar cells such as low cos...Because crystalline silicon thin film （CSiTF） solar cells possess the advantages of crystalline silicon solar cells such as high ef- ficiency and stable performance and those of thin film solar cells such as low cost and so on, it is regarded as the next genera- tion solar cell technology, which is most likely to replace the existing crystalline silicon solar cell technology. In this paper, we performed device simulation on the epitaxial CSiTF solar cell by using PCI D software. In order to make simulation results closer to the actual situation, we adopted a more realistic device structure and parameters. On this basis, we comprehensively and systematically investigated the effect of physical parameters of back surface field （BSF） layer, base and emitter, electrical quality of crystalline silicon active layer, situation of surface passivation, internal recombination and p-n junction leakage on the optoelectronic performance of the epitaxial CSiTF solar cell. Among various factors affecting the efficiency of the epitaxial CSiTF solar cell, we identified the three largest efficiency-affecting parameters. They are the base minority carrier diffusion length, the diode dark saturation current and the front surface recombination velocity in order. Through simulations, we found that the base is not the thicker the better, and the base minority carrier diffusion length must be taken into account when deter- mining the optimal base thickness. When the base minority carrier diffusion length is smaller, the optimal base thickness should be less than or equal to the base minority carrier diffusion length; when the base minority carrier diffusion length is larger, the base minority carrier diffusion length should be at least twice the optimal base thickness. In addition, this paper not only illustrates the simulation results but also explains their changes from the aspect of physical mechanisms. Because epitaxi- al CSiTF solar cells possess a device structure that is similar to crystalline silicon solar cells, the conclusions drawn in this pa- per are also applied to crystalline silicon solar cells to a certain extent, particularly to thin silicon solar cells which are the hot- test research topic at present.展开更多
The performance of internal rear surface reflectance of crystalline silicon solar cells is becoming more and more important with the decrease of thickness of the silicon wafers.In this paper PC1D was used to simulate ...The performance of internal rear surface reflectance of crystalline silicon solar cells is becoming more and more important with the decrease of thickness of the silicon wafers.In this paper PC1D was used to simulate the correlations between the rear surface reflectance and the electrical as well as optical properties of the solar cells.The results showed that the short circuit current,open circuit voltage and quantum efficiency were all enhanced with the increase of the rear reflectance.When the rear reflectance increased from 60%to 100%,the short circuit current,open circuit voltage and maximum output power were improved by about 0.128 A,0.007 V,and 0.066 W,respectively.The internal quantum efficiency was improved by 39.9%,the external quantum increased by 17.4%,and the efficiency of the solar cells was enhanced by 0.4%at 1100 nm wavelength.The screen-printing was selected to prepare SiNx/Al reflector,and experimental results showed that the SiNx/Al reflector has desired characteristic of internal rear reflectance,with the reflectivity of 15%higher than that of conventional aluminum BSF at 1100 nm wavelength.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 50802118)Science & Technology Research Project of Guangdong Province (Grant Nos. 2011A032304001,2010B090400020)the Fundamental Research Funds for the Central Universities (Grant No. 2011300003161469)
文摘Because crystalline silicon thin film （CSiTF） solar cells possess the advantages of crystalline silicon solar cells such as high ef- ficiency and stable performance and those of thin film solar cells such as low cost and so on, it is regarded as the next genera- tion solar cell technology, which is most likely to replace the existing crystalline silicon solar cell technology. In this paper, we performed device simulation on the epitaxial CSiTF solar cell by using PCI D software. In order to make simulation results closer to the actual situation, we adopted a more realistic device structure and parameters. On this basis, we comprehensively and systematically investigated the effect of physical parameters of back surface field （BSF） layer, base and emitter, electrical quality of crystalline silicon active layer, situation of surface passivation, internal recombination and p-n junction leakage on the optoelectronic performance of the epitaxial CSiTF solar cell. Among various factors affecting the efficiency of the epitaxial CSiTF solar cell, we identified the three largest efficiency-affecting parameters. They are the base minority carrier diffusion length, the diode dark saturation current and the front surface recombination velocity in order. Through simulations, we found that the base is not the thicker the better, and the base minority carrier diffusion length must be taken into account when deter- mining the optimal base thickness. When the base minority carrier diffusion length is smaller, the optimal base thickness should be less than or equal to the base minority carrier diffusion length; when the base minority carrier diffusion length is larger, the base minority carrier diffusion length should be at least twice the optimal base thickness. In addition, this paper not only illustrates the simulation results but also explains their changes from the aspect of physical mechanisms. Because epitaxi- al CSiTF solar cells possess a device structure that is similar to crystalline silicon solar cells, the conclusions drawn in this pa- per are also applied to crystalline silicon solar cells to a certain extent, particularly to thin silicon solar cells which are the hot- test research topic at present.
基金supported by the National Natural Science Foundation of China(Grant No.60876044)the Scientific and Technological Key Research Projects of Guangdong Province(Grant No.2007A010700002)
文摘The performance of internal rear surface reflectance of crystalline silicon solar cells is becoming more and more important with the decrease of thickness of the silicon wafers.In this paper PC1D was used to simulate the correlations between the rear surface reflectance and the electrical as well as optical properties of the solar cells.The results showed that the short circuit current,open circuit voltage and quantum efficiency were all enhanced with the increase of the rear reflectance.When the rear reflectance increased from 60%to 100%,the short circuit current,open circuit voltage and maximum output power were improved by about 0.128 A,0.007 V,and 0.066 W,respectively.The internal quantum efficiency was improved by 39.9%,the external quantum increased by 17.4%,and the efficiency of the solar cells was enhanced by 0.4%at 1100 nm wavelength.The screen-printing was selected to prepare SiNx/Al reflector,and experimental results showed that the SiNx/Al reflector has desired characteristic of internal rear reflectance,with the reflectivity of 15%higher than that of conventional aluminum BSF at 1100 nm wavelength.
