Racah Institute of Physics and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
Phys Rev Lett. 2012 Feb 17;108(7):076603. doi: 10.1103/PhysRevLett.108.076603. Epub 2012 Feb 14.
We investigated the electronic properties around grain boundaries of polycrystalline Cu(In(1-x),Ga(x)Se(2)) films as a function of Ga content, using scanning tunneling spectroscopy. Spectra acquired on samples with low Ga content (x=0 and 0.33) reveal downward band bending with respect to adjacent p-type grains, suggesting type inversion at the surface of grain boundaries. Such a behavior was not observed for samples with high Ga contents. These results are consistent with our atomic force microscopy data and may shed light on the origin of the x-dependent efficiency for polycrystalline Cu(In(1-x),Ga(x)Se(2))-based solar cells.
我们使用扫描隧道光谱法研究了多晶 Cu(In(1-x),Ga(x)Se(2)) 薄膜晶界周围的电子性质随 Ga 含量的变化。在 Ga 含量较低（x=0 和 0.33）的样品上获得的光谱显示相对于相邻的 p 型晶粒向下的能带弯曲，表明晶界表面的类型反转。对于 Ga 含量较高的样品，没有观察到这种行为。这些结果与我们的原子力显微镜数据一致，可能有助于解释多晶 Cu(In(1-x),Ga(x)Se(2))基太阳能电池中 x 依赖性效率的起源。
