利用磁控溅射方法改变氧气含量制备了一系列NiO∶Cu/ZnO异质pn结。实验结果表明,氧含量对NiO∶Cu/ZnO异质pn结电学影响很大。相对于纯氩溅射,引入一定氧气(O2/(Ar+O2)比例为30%)后,NiO∶Cu/ZnO异质pn结的整流特性明显得到改善。与此同时,NiO∶Cu/ZnO异质pn结的光透过率也从40%增大到80%。这可能是由于氧气的轻量引入致使NiO∶Cu/ZnO异质pn结的结晶得到改善,薄膜内缺陷减少所致。进一步提高氧气含量,直到O2/(Ar+O2)比例至80%后,异质结的整流特性有所削弱,这可能是由于过多氧气的引入造成薄膜缺陷再次增多,进而影响到异质结的整流特性。这一结论得到了EDS、XRD、AFM和UV结果的支持。
Ni O∶ Cu / Zn O pn heterojunctions with different oxygen concentration were fabricated by magnetron sputtering technology. The rectifying characteristics of Ni O ∶ Cu / Zn O pn heterojunctions have been improved with the O_2/( Ar + O_2) ratio from 0% to 30%,where the average optical transmittance increases from 40% to 80% in the visible range,which may be explained by the improved crystallization due to the reduced defects. When the oxygen partial pressure increases to 80%,the rectifying property is depressed again because of introducing more oxygen into the sample and the appearance of more defects. These results are also evidenced by EDS,XRD,AFM and UV results.