CdS薄膜中"白斑"的研究

本论文对CdS薄膜中的"白斑"进行了研究.化学水浴沉积法(CBD)制备CdS薄膜所需要的化学反应物包括硫脲、氨水、镉盐和铵盐等.文中采用两种镉盐和铵盐来沉积CdS薄膜:氯化镉和氯化铵,乙酸镉和乙酸铵.所沉积的CdS薄膜的表观形貌由SEM表征,成分由EDX表征.当镉盐和铵盐分别采用氯化镉和氯化铵时,生成的薄膜中存在大量的"白斑".这些"白斑"的成分不是CdS,而是(CdCl)2S.增加氨水的浓度可以大大减少这些"白斑",但是不能彻底消除这些"白斑".当镉盐和铵盐分别采用乙酸镉和乙酸铵时,生成的薄膜均匀、平整,薄膜中根本就不存在所谓的"白斑".因此,沉积CdS薄膜时,镉盐和铵盐不宜采用氯化镉和氯化铵,应该采用乙酸镉和乙酸铵.

Research on White Flecks in CdS Thin Films

This paper researches white flecks in CdS thin films.The CdS thin films were deposited from a chemical bath containing thiourea,ammonia,cadmium salt and aminium salt using CBD technique.Two kinds of cadmium salts and aminium salts were used to deposite CdS thin films:cadmium chloride and ammonium chloride, cadmium acetate and ammonium acetate.The CdS thin films were characterized by SEM for their surface morphologies and EDX for their compositional analyses.There were a lot of white flecks in CdS thin films when cadmium chloride and ammonium chloride were used to deposite CdS thin films.The composition of the white flecks is not CdS but (CdCl)_2S.Increasing ammonia concentration is able to reduce the white flecks greatly,but not remove them completely.The CdS thin films were uniform and smooth,and there were no white flecks in them at all when cadmium acetate and ammonium acetate were used to deposite CdS thin films.Therefore,it is cadmium acetate and ammonium acetate that should be used to deposite CdS thin films.