反应磁控溅射法制备F掺杂ZnO(FZO)薄膜的结构和透明导电性能

Structure and transparent conductive properties of F-doped ZnO(FZO)thin films prepared by reactive magnetron sputtering

以Zn/ZnO/ZnF_(2)混合物为靶材,在衬底温度(T_(s))为150℃和300℃、溅射气氛为Ar+O_(2)和Ar+H_(2)下反应溅射制备F掺杂ZnO(FZO)薄膜,研究气体流量、T_(s)以及溅射气氛对薄膜结构及透明导电性能的影响。结果表明:对于Ar+O_(2)下制备的FZO薄膜,T_(s)=300℃时有利于制备出具有(002)择优取向、结晶度高、压应力低且透明导电性能较好的薄膜。对于Ar+H_(2)下制备的薄膜,T_(s)增大到300℃虽然提高了薄膜结晶度和透光性,降低了压应力,但薄膜厚度明显降低,薄膜导电性能变差。比较两种气氛下制备的FZO薄膜,发现Ar+H_(2)下制备的薄膜可在150℃和0.8~3.2 mL·min^(-1)的H_(2)流量范围内得到更好的透明导电性能(电阻率为3.5×10^(-3)Ω·cm,可见光平均透光率为87%)。讨论Ar+H_(2)气氛时H等离子的刻蚀作用与H掺杂、Ar+O_(2)气氛时O离子的轰击作用与薄膜氧缺陷的变化、T_(s)升高时沉积原子反应活性与迁移能力增强以及Eg与载流子浓度的关系。

F-doped ZnO(FZO)films were prepared by reactive sputtering using Zn/ZnO/ZnF_(2)mixture as the target at substrate temperature(T_(s))of 150℃and 300℃and sputtering atmosphere of Ar+O_(2)and Ar+H_(2).The effect of gas flux,T_(s),and sputtering atmosphere on the structure and transparent conductive properties of the thin film was investigated.The results show that for FZO films prepared under Ar+O_(2),T_(s)=300℃is conductive to the preparation of films with(002)preferred orientation,high crystallinity,low compressive stress and good transparent conductive properties.For the films prepared under Ar+H_(2),with the increase of T_(s)to 300℃,the crystallinity and transmittance of the films improve and the compressive stress reduces,but the film thickness significantly reduces and leads to the deterioration of the conductive properties of the films.The FZO films prepared in the two atmospheres are compared,and it is found that the films prepared in Ar+H_(2)can obtain better transparent conductive properties(the resistivity of 3.5×10^(-3)Ω·cm and the average transmittance in visible range of 87%)at 150℃and in H_(2)flux range of 0.8-3.2 mL·min^(-1).The etching effect of H plasma and H doping in the Ar+H_(2)atmosphere,the bombardment of O ions and the change of oxygen defects of the films in the Ar+O_(2)atmosphere,the enhancement in reaction activity and mobility of deposited atoms with increasing T_(s),and the relationship between Eg and carrier concentration are discussed in detail.