对低温下制得的CdS薄膜电学性质的研究

Investigation on Electronic Quality of Cadmium Sulphide Layers Deposited at Low Temperature

采用化学水浴沉积法研究在低温条件下以及硫尿浓度不同的溶液中生长出的硫化镉薄膜的电学性质。采用X-射线衍射(XRD)仪确定退火后的样品是六方相,在(002)、(112)和(004)方向优势生长;使用紫外-可见分光光度计发现各样品的光学性质符合硫化镉作为窗口材料的要求;利用原子力显微镜发现各样品的晶粒形状、均匀性和致密性差异较大;利用化学工作站进行样品的电容-电压测试发现,各样品的掺杂浓度差异很大,其中有的样品掺杂浓度为1.2×1017cm-3,这样的掺杂浓度适合制造光电器件。

Chemical bath deposition method was used to investigate the electronic quality of cadmium sulphide layers deposited in different thiourea concentrations at low temperature. Using X-ray diffraction, it was found the CdS layers grown after annealing were hexagonal with （002）, （112） and （004） preferential orientation. The optical qualities of the CdS layers tested by the ultraviolet-visible Spectrophotometer could meet the requirements as window material. Atomic force microscopy measurement indicated that there were great differences in the crystal size, crystal shapes and crystal compactness among the samples. Capacitance-voltage measurement indicated that one of the moderate doping concentrations of 1.2× 10^17 cm^-3 was suitable for electronic device fabrication, but the doping concentrations of different samples still performed great differences.