Electrodeposition of zinc cadmium sulphide thin films from acidic aqueous electrolyte solution at room temperature

摘要

Thin film of CdS and ZnxCd1-xS have been used in optical and opto-electronic devices. The band gap energy of ternary ZnvCdi_ VS can be varied between that of CdS (-2.4 ev) and ZnS (-3.7 eV) by varying the Zn/Cd ratio. A number of techniques such as vacuum evaporation [1,2], MOVPE growth on GaAs [3], spray pyrolysis [4] and electrodeposition [5, 6] have been utilized to prepare Zn,Cd1_i.S thin films. Electrodeposited CdS films have been obtained potentiostatically from aqueous electrolyte solution under d.c. [7] as well as periodic pulse [8] conditions, and galvanostatically from non-aqueous solutions [5, 9]. The potentiostatic electrodeposition of ZnxCd1-x.S has been done at 90 °C from aqueous electrolyte solution [6]. We have already electro-deposited ZnvCdi_,.S films galvanostatically from non-aqueous electrolyte solution at 120 °C onto transparent conducting glass [5]. In this letter, we report on the potentiostatic electrodeposition of ZnA.Cdt_A.S from acidic aqueous electrolyte solution at room temperature.