Cu(In,Ga)Se_2太阳能电池快速热退火效应

Rapid thermal annealing effect on Cu(In,Ga)Se_2 solar cells

利用光致发光(PL)分析快速热退火对Cu(In,Ga)Se2(CIGS)电池的影响,研究退火对薄膜缺陷的影响。Cu(In,Ga)Se2电池的PL谱中总共有7个峰,即2个可见波段峰和5个红外波段峰。退火温度较低,可减少薄膜体内缺陷,提高载流子浓度,改善薄膜质量;退火温度过高,则会引起正常格点处元素扩散,元素化学计量比改变,体内缺陷增加,吸收层带隙降低,反而会对CIGS薄膜造成破坏。

The paper studies the rapid thermal annealing（RTA） effect on Cu（In, Ga）Se2 （CIGS） solar cells at different an- nealing temperatures by photoluminescence（PL）. Continuous RTA was applied to CIGS solar cells to study annealing effect on film defects. Seven peaks exist in CIGS PL spectra： two in visible light region, the others in infrared region. When the temperature is relatively low, RTA treatment can improve the film quality because of the decrease of defects and the increase of carriers. High temperature RTA treatment will lead to elements diffusion between layers and change of stoichiometrie ratio, increasing interface states and decreasing the bandgap of absorber layer, and thus destroy the device structures.