反应磁控溅射制备CdTe太阳电池前电极ITO薄膜的性质研究

使用反应直流磁控溅射法在玻璃衬底上制备了ITO薄膜作为CdTe多晶薄膜太阳电池的前电极,研究了氧分压和衬底温度对ITO薄膜光电性能及结构的影响.通过四探针、紫外可见分光光度仪,X射线衍射(XRD)和霍尔测试仪等测试手段对薄膜进行了表征.结果表明:随着氧分压和衬底温度的升高,ITO薄膜在可见光区域的透过性能明显增强,但是薄膜的载流子浓度下降,霍尔迁移率也逐渐降低,同时薄膜的电阻率逐渐增大.在结果分析的基础上,选用衬底温度300℃,1.4%的氧分压条件制备出可见光透过率在80%以上,电阻率为5.3×10-4?·cm的ITO薄膜,将其应用于碲化镉多晶薄膜太阳电池,电池的转换率可以达到10.7%.

Properties of ITO films as the front electrode of CdTe solar cells deposited by reactive magnetron sputtering

The ITO thin films as the front electrode of CdTe solar cell were prepared on glass substrate by DC magnetron sputtering. The effects of substrate temperature and oxygen partial pressure on the microstructure, electrical and optical properties of the ITO thin films were studied by Four-point probe, UV-vis spectrometer, X-ray diffraction （XRD） and Hall measurement. The results showed that as oxygen partial pressure and substrate temperature increased, the Hall mobility and carrier concentration of the films decreased while the resistivity and transmittance increased. On the basis of analysis, the ITO films which was applied to CdTe polycrystalline solar cells were prepared at 300℃ of the substrate temperature and 1.4% of the oxygen partial. The visible light transmittance of the films could be 80% or more and the resistivity was 5.3×10^-4 Ω·cm. As a result, 10.7% conversion efficiency of CdTe solar cell was obtained.