IWO缓冲层对MOCVD-ZnO：B薄膜性能的影响研究

Influence of IWO buffer layer on the properties of MOCVD-ZnO:B thin films

金属有机化学气相沉积(MOCVD)技术生长的绒面ZnO透明导电(ZnO-TCO)薄膜应用于Si基薄膜太阳电池上能够形成"陷光结构",以提高薄膜太阳电池效率和稳定性。本文将电子束反应蒸发技术生长的掺W的In2O3(In2O3:W,(IWO)薄膜作为缓冲层,应用于MOCVD-ZnO:B薄膜与玻璃之间,可促进ZnO:B薄膜的生长,并且有效提升薄膜的光散射特性。当IWO缓冲层厚度为20nm时,获得的IWO/ZnO:B薄膜的电阻率为2.07×10-3Ω.cm,迁移率为20.9cm2.V-1.s-1,载流子浓度为1.44×1020 cm-3;同时,薄膜具有的透过率大于85%,且在550nm处绒度较ZnO:B薄膜提高了约9.5%,在800nm处绒度较ZnO:B薄膜提高了约4.5%。

Light trapping effect is formed when the textured ZnO：B-TCO thin films deposited by MOCVD technique are used in Si-based thin film solar cells,which is important for improving the short-circuit current and the stability of thin film solar cells.In this paper,In2O3：W（IWO） thin films deposited by electron beam evaporation were grown between the glass substrates and ZnO：B thin films as buffer layers,which can promote the growth of ZnO：B thin films.And the scattering characteristics of ZnO：B thin films are improved effectively.When the thickness of IWO thin film is 20 nm,bi-layer IWO/ZnO：B thin films with the resistivity of 2.07×10-3 Ω·cm,mobility of ～20.9 cm2·V-1·s-1 and carrier concentration of 1.44×1020 cm-3 are obtained.Meanwhile,these bi-layer thin films present high transparencies over 85%,and the haze of these thin films increases by about 9.5% at 500 nm wavelength and about 4.5% at 800 nm wavelength.