背表面形貌对硅太阳电池效率的影响

Different processes are used on the back surface of silicon wafers to form cells falling into three groups：textured, planar, and sawed-off pyramid back surface.The characteristic parameters of the cells, ISC, VOC, FF, Pm, and Eff, are measured.All these parameters of the planar back surface cells are the best.The FF, Pm, and Eff of sawed-off pyramid back surface cells are superior to textured back surface cells, although ISC and VOC are lower.The parasitic resistance is analyzed to explain the higher FF of the sawed-off pyramid back surface cells.The cross-section scanning electron microscopy（SEM） pictures show the uniformity of the aluminum-silicon alloy, which has an important effect on the back surface recombination velocity and the ohmic contact.The measured value of the aluminum back surface field thickness in the SEM picture is in good agreement with the theoretical value deduced from the Al-Si phase diagram.It is shown in an external quantum efficiency（EQE） diagram that the planar back surface has the best response to a wavelength between 440 and 1000 nm and the sawed-off back surface has a better long wavelength response.     

温度对多晶硅太阳电池性能影响的研究

对商业用冶金级和太阳能级多晶硅太阳电池不同温度下的性能参数做了分析,验证了太阳能级硅电池的性能优势。实验结果表明,随着温度T的升高,开路电压V_(oc),最大输出功率P_m,转换效率η近似线性下降,短路电流I_(sc)近似线性上升,填充因子FF的实验值和理论值变化趋势一致,当T40℃时,FF随T升高明显下降。对开路电压V_(oc)随温度T升高的线性下降速率dV_(oc)/dT进行定量分析。dI_(sc)/dT变化量与dV_(oc)/dT相比可以忽略。     

热氧化生长的SiO2钝化膜对晶体硅太阳电池性能的影响

使用干氧热氧化的方法在晶体硅太阳电池表面生长SiO2钝化膜。结果表明:在780℃下生长的氧化薄膜钝化效果较好,实验检测少子寿命提高了8.3μs,以此为基础制备的太阳电池转换效率达到17.38%。实验还对氮气气氛下的氧化进行研究,发现当氮气流量为10L/min时,能强化薄膜的钝化效果,少子寿命可提高9.4μs。     

浅谈技工院校的《微机原理与接口技术》课程的教学体会

《微机原理与接口技术》是一门非常重要的专业课,该课程理论性、实践性及应用性都非常地强。本人在多年的教学过程中研究发现,这门课在讲授时存在很多问题。本文结合本人多年来的教学实践,谈谈对本门课程的几点教学体会。