论文标题
在倒数多期太阳能电池的Movpe生长期间
Point-defects assisted Zn-diffusion in AlGaInP/GaInP systems during the MOVPE growth of inverted multijunction solar cells
论文作者
论文摘要
我们通过比较模仿后表面场（BSF）的不同结构（BSF）和Gainp子细胞的基础层进行比较，研究了Movpe生长的Algainp/Gainp系统中Zn扩散的动力学。通过分析二级离子质谱法（SIMS），电化学电容 - ECV（ECV）和光谱分辨的阴极发光（CL）测量值，我们提供了实验证据，表明1）1）Zn扩散在隧道结插口插口插口大管层的生长过程中被注入的点缺陷增强； 2）该过程的强度取决于阴极掺杂水平，并且发生在不同的阴极材料中； 3）移动Zn的带正电荷和4）扩散机制减少了Gainp中的碎序。我们证明，使用屏障层可以减轻点缺陷的扩散，以免它们到达Zn掺杂层，从而阻止其扩散。最后，通过比较不同浓度的电I-V曲线来评估Zn扩散对具有不同Zn profiles的太阳能电池的影响。结果排除了BSF中内部障碍的引入，但说明了典型生长条件下的锌扩散如何到达发射极，并显着影响串联电阻，以及其他效果。
We investigate the dynamics of Zn diffusion in MOVPE-grown AlGaInP/GaInP systems by the comparison of different structures that emulate the back-surface field (BSF) and base layers of a GaInP subcell integrated into an inverted multijunction solar cell structure. Through the analysis of secondary ion mass spectroscopy (SIMS), electrochemical capacitance-voltage (ECV) and spectrally resolved cathodoluminescence (CL) measurements, we provide experimental evidence that 1) the Zn diffusion is enhanced by point defects injected during the growth of the tunnel junction cathode layer; 2) the intensity of the process is determined by the cathode doping level and it happens for different cathode materials; 3) the mobile Zn is positively charged and 4) the diffusion mechanism reduces the CuPt ordering in GaInP. We demonstrate that using barrier layers the diffusion of point defects can be mitigated, so that they do not reach Zn-doped layers, preventing its diffusion. Finally, the impact of Zn diffusion on solar cells with different Zn-profiles is evaluated by comparing the electrical I-V curves at different concentrations. The results rule out the introduction of internal barriers in the BSF but illustrate how Zn diffusion under typical growth condition can reach the emitter and dramatically affect the series resistance, among other effects.
