后处理对近空间升华法制备CdS薄膜性能影响研究

Influence of annealing on the properties of CdS polycrystalline thin films deposited by close-spaced sublimation

将近空间升华法(CSS)沉积所得的CdS薄膜进行退火处理,利用XRD、SEM、暗电导温度关系研究不同退火条件对CdS多晶薄膜性能的影响.结果表明退火后CdS多晶薄膜在(002)面上具有择优取向;退火促使再结晶并促进晶粒长大;暗电导(dark-σ)随退火温度增加而增加,暗电导激活能(Ea)随退火温度的增加而减少.最后得到较优化的退火条件,获得适合作为CdTe太阳电池窗口层的CdS薄膜.

In this paper, the CdS thin films deposited by close-spaced sublimation have been annealed. The properties of films were studied by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and the relationship of dark conductivities - temperature （σ-T）. The results showed that （002） preferred direction of crystalline grains still exists after annealing; the treatment can promote recrystallization and grain growth; With the annealing temperatures increasing, the dark conductivities（a-dark） increase while the dark conductivity activation energy （Ea） decreases. Finally, an optimization anneal condition has been achieved and the CdS thin films as windows layers of CdTe solar cells have been obtained.