In this paper, we extend the concept of back surface recombination through a study of a silicon mono facial solar cell in static regime and under polychromatic illumination. Back surface recombination velocities noted...In this paper, we extend the concept of back surface recombination through a study of a silicon mono facial solar cell in static regime and under polychromatic illumination. Back surface recombination velocities noted Sbe, Sbj and Sbr are determined for which respectively we derived, the power, the fill factor and the conversion efficiency, that become constant whatever the thickness of the solar cell. We have then obtained the expression of the minority carrier’s density in the base from the continuity equation. We then have determined the photocurrent density, the photo voltage, the power, the fill factor and finally the conversion efficiency.展开更多
New expressions of back surface recombination of excess minority carriers in the base of silicon solar are expressed dependent on both, the thickness and the diffusion coefficient which is in relationship with the dop...New expressions of back surface recombination of excess minority carriers in the base of silicon solar are expressed dependent on both, the thickness and the diffusion coefficient which is in relationship with the doping rate. The optimum thickness thus obtained from the base of the solar cell allows the saving of the amount of material needed in its manufacture without reducing its efficiency.展开更多
The minority carrier’s recombination velocity at the junction and at the back surface is used for the modeling and determination of the optimum thickness of the base of a silicon solar cell in the static regime, unde...The minority carrier’s recombination velocity at the junction and at the back surface is used for the modeling and determination of the optimum thickness of the base of a silicon solar cell in the static regime, under magnetic field and temperature influence. This study takes into account the Umklapp process and the Lorentz effect on the minority carriers photogenerated in the base.展开更多
Base optimum thickness is determined for a front illuminated bifacial silicon solar cell n<sup>+</sup>-p<span style="font-size:10px;">-</span>p<sup>+</sup> under magnetic ...Base optimum thickness is determined for a front illuminated bifacial silicon solar cell n<sup>+</sup>-p<span style="font-size:10px;">-</span>p<sup>+</sup> under magnetic field. From the magneto transport equation relative to excess minority carriers in the base, with specific boundary conditions, the photocurrent is obtained. From this result the expressions of the carrier’s recombination velocity at the back surface are deducted. These new expressions of recombination velocity are plotted according to the depth of the base, to deduce the optimum thickness, which will allow the production, of a high short-circuit photocurrent. Calibration relationships of optimum thickness versus magnetic field were presented according to study ranges. It is found that, applied magnetic field imposes a weak thickness material for solar cell manufacturing leading to high short-circuit current.展开更多
利用TCAD半导体器件仿真软件对N型插指背接触(Interdigitated Back Contact,IBC)单晶硅太阳电池发射区半宽度进行研究,全面系统地分析了在不同背表面复合速率的情况下,发射区半宽度对IBC太阳电池短路电流密度(JSC)、开路电压(VOC...利用TCAD半导体器件仿真软件对N型插指背接触(Interdigitated Back Contact,IBC)单晶硅太阳电池发射区半宽度进行研究,全面系统地分析了在不同背表面复合速率的情况下,发射区半宽度对IBC太阳电池短路电流密度(JSC)、开路电压(VOC)、填充因子(FF)及转换效率(Eff)的影响。结果表明:随着背表面复合速率的增大,对于不同发射区半宽度的情况,IBC太阳电池JSC、VOC、FF及Eff均显著降低。当背表面复合速率一定时,发射区半宽度越大,JSC、VOC越高,而FF越低。随着发射区半宽度的增大,IBC太阳电池Eff呈现先增大后减小的变化特点。当背表面复合速率较小(50~500 cm/s)时,最优的发射区半宽度为800μm。当背表面复合速率较高(≥5000 cm/s)时,最优的发射区半宽度为1200μm。展开更多
This work deals with determining the optimum thickness of the lamella wafer of silicon solar cell. The (p) base region makes up the bulk of the thickness of the wafer. This thickness has always been a factor limiting ...This work deals with determining the optimum thickness of the lamella wafer of silicon solar cell. The (p) base region makes up the bulk of the thickness of the wafer. This thickness has always been a factor limiting the performance of the solar cell, as it produces the maximum amount of electrical charges, contributing to the photocurrent. Determining the thickness of the wafer cannot be only mechanical. It takes into account the internal physical mechanisms of generation-diffusion-recombination of excess minority carriers. They are also influenced by external factors such as temperature and magnetic field. Under these conditions, magneto transport equation is required to be applied on excess minority carrier in lamella base silicon solar cell. It yields maximum diffusion coefficient which result on Lorentz law and Umklapp process. Then from photocurrent, back surface recombination velocity expressions are derived, both maximum diffusion coefficient and thickness dependent. The plot of the back surface recombination calibration curves as function of lamella width, leads to its maximum values, trough intercept points. Lamella optimum width is then obtained, both temperature and magnetic field dependent and expressed in relationships to show the required base thickness in the elaboration process.展开更多
The ac recombination velocity of the excess minority carriers, in the back surface of a silicon solar cell with a vertical junction connected in series, is developed through Einstein’s law giving the diffusion coeffi...The ac recombination velocity of the excess minority carriers, in the back surface of a silicon solar cell with a vertical junction connected in series, is developed through Einstein’s law giving the diffusion coefficient of minority carriers according to temperature, through mobility. The frequency spectrum of both, amplitude and phase, are produced for the diffusion coefficient and the recombination velocity in the rear face, in order to identify the parameters of equivalent electric models.展开更多
Excess minority carrier’s diffusion equation in the base of monofaciale silicon solar cell under frequency modulation of monochromatic illumination is resolved. Using conditions at the base limits involving recombina...Excess minority carrier’s diffusion equation in the base of monofaciale silicon solar cell under frequency modulation of monochromatic illumination is resolved. Using conditions at the base limits involving recombination velocities <i>Sf</i> and <i>Sb</i>, respectively at the junction (n<sup>+</sup>/p) and back surface (p<sup>+</sup>/p), the AC expression of the excess minority carriers’ density <i>δ</i> (<i>T</i>, <i>ω</i>) is determined. The AC density of photocurrent <i>J<sub>ph</sub></i> (<i>T</i>, <i>ω</i>) is represented versus recombination velocity at the junction for different values of the temperature. The expression of the AC back surface recombination velocity <i>Sb</i> of minority carriers is deduced depending on the frequency of modulation, temperature, the electronic parameters (<i>D</i> (<i>ω</i>)) and the thickness of the base. Bode and Nyquist diagrams are used to analyze it.展开更多
文摘In this paper, we extend the concept of back surface recombination through a study of a silicon mono facial solar cell in static regime and under polychromatic illumination. Back surface recombination velocities noted Sbe, Sbj and Sbr are determined for which respectively we derived, the power, the fill factor and the conversion efficiency, that become constant whatever the thickness of the solar cell. We have then obtained the expression of the minority carrier’s density in the base from the continuity equation. We then have determined the photocurrent density, the photo voltage, the power, the fill factor and finally the conversion efficiency.
文摘New expressions of back surface recombination of excess minority carriers in the base of silicon solar are expressed dependent on both, the thickness and the diffusion coefficient which is in relationship with the doping rate. The optimum thickness thus obtained from the base of the solar cell allows the saving of the amount of material needed in its manufacture without reducing its efficiency.
文摘The minority carrier’s recombination velocity at the junction and at the back surface is used for the modeling and determination of the optimum thickness of the base of a silicon solar cell in the static regime, under magnetic field and temperature influence. This study takes into account the Umklapp process and the Lorentz effect on the minority carriers photogenerated in the base.
文摘Base optimum thickness is determined for a front illuminated bifacial silicon solar cell n<sup>+</sup>-p<span style="font-size:10px;">-</span>p<sup>+</sup> under magnetic field. From the magneto transport equation relative to excess minority carriers in the base, with specific boundary conditions, the photocurrent is obtained. From this result the expressions of the carrier’s recombination velocity at the back surface are deducted. These new expressions of recombination velocity are plotted according to the depth of the base, to deduce the optimum thickness, which will allow the production, of a high short-circuit photocurrent. Calibration relationships of optimum thickness versus magnetic field were presented according to study ranges. It is found that, applied magnetic field imposes a weak thickness material for solar cell manufacturing leading to high short-circuit current.
文摘利用TCAD半导体器件仿真软件对N型插指背接触(Interdigitated Back Contact,IBC)单晶硅太阳电池发射区半宽度进行研究,全面系统地分析了在不同背表面复合速率的情况下,发射区半宽度对IBC太阳电池短路电流密度(JSC)、开路电压(VOC)、填充因子(FF)及转换效率(Eff)的影响。结果表明:随着背表面复合速率的增大,对于不同发射区半宽度的情况,IBC太阳电池JSC、VOC、FF及Eff均显著降低。当背表面复合速率一定时,发射区半宽度越大,JSC、VOC越高,而FF越低。随着发射区半宽度的增大,IBC太阳电池Eff呈现先增大后减小的变化特点。当背表面复合速率较小(50~500 cm/s)时,最优的发射区半宽度为800μm。当背表面复合速率较高(≥5000 cm/s)时,最优的发射区半宽度为1200μm。
文摘This work deals with determining the optimum thickness of the lamella wafer of silicon solar cell. The (p) base region makes up the bulk of the thickness of the wafer. This thickness has always been a factor limiting the performance of the solar cell, as it produces the maximum amount of electrical charges, contributing to the photocurrent. Determining the thickness of the wafer cannot be only mechanical. It takes into account the internal physical mechanisms of generation-diffusion-recombination of excess minority carriers. They are also influenced by external factors such as temperature and magnetic field. Under these conditions, magneto transport equation is required to be applied on excess minority carrier in lamella base silicon solar cell. It yields maximum diffusion coefficient which result on Lorentz law and Umklapp process. Then from photocurrent, back surface recombination velocity expressions are derived, both maximum diffusion coefficient and thickness dependent. The plot of the back surface recombination calibration curves as function of lamella width, leads to its maximum values, trough intercept points. Lamella optimum width is then obtained, both temperature and magnetic field dependent and expressed in relationships to show the required base thickness in the elaboration process.
文摘The ac recombination velocity of the excess minority carriers, in the back surface of a silicon solar cell with a vertical junction connected in series, is developed through Einstein’s law giving the diffusion coefficient of minority carriers according to temperature, through mobility. The frequency spectrum of both, amplitude and phase, are produced for the diffusion coefficient and the recombination velocity in the rear face, in order to identify the parameters of equivalent electric models.
文摘Excess minority carrier’s diffusion equation in the base of monofaciale silicon solar cell under frequency modulation of monochromatic illumination is resolved. Using conditions at the base limits involving recombination velocities <i>Sf</i> and <i>Sb</i>, respectively at the junction (n<sup>+</sup>/p) and back surface (p<sup>+</sup>/p), the AC expression of the excess minority carriers’ density <i>δ</i> (<i>T</i>, <i>ω</i>) is determined. The AC density of photocurrent <i>J<sub>ph</sub></i> (<i>T</i>, <i>ω</i>) is represented versus recombination velocity at the junction for different values of the temperature. The expression of the AC back surface recombination velocity <i>Sb</i> of minority carriers is deduced depending on the frequency of modulation, temperature, the electronic parameters (<i>D</i> (<i>ω</i>)) and the thickness of the base. Bode and Nyquist diagrams are used to analyze it.