N掺杂Cu2O薄膜的低温沉积及快速热退火研究

采用氧化亚铜(Cu_2O)陶瓷靶,利用射频磁控溅射沉积法在氮气和氩气的混合气氛下制备了N掺杂Cu_2O(Cu_2O∶N)薄膜,并在N_2气氛下对薄膜进行了快速热退火处理,研究了N_2流量和退火温度对Cu_2O∶N薄膜的生长行为、物相结构、表面形貌及光电性能的影响。结果显示,在衬底温度300℃、N_2流量12sccm条件下生长的薄膜为纯相Cu_2O薄膜;在N_2气氛下对预沉积薄膜进行快速热退火处理不影响薄膜的物相结构,薄膜的结晶质量随退火温度(450℃)的升高而显著改善;快速热退火处理能改善薄膜的结晶质量和缺陷,降低光生载流子的散射,增强载流子的传输,预沉积Cu_2O∶N薄膜经400℃退火处理后展示出较好的电性能,薄膜的霍尔迁移率(μ)为27.8cm~2·V~(-1)·s~(-1)、电阻率(ρ)为2.47×10~3Ω·cm。研究表明低温溅射沉积和快速热退火处理能有效改善Cu_2O∶N薄膜的光电性能。

Study on N-doped Cu2O Thin Film Fabricated by Low Temperature Deposition and Rapid Thermal Annealing

The N-doped Cu2O(Cu2O:N)thin films were deposited by radio frequency magnetron sputtering a Cu2O target in N2 and Ar mixture atmosphere,and then the as-deposited Cu2O:N thin films were annealed by rapid thermal annealing(RTA)in N2 atmosphere.Effects of N2 flow rates and annealing temperatures on growth behaviour,crystalline structures,surface morphologies,optical and electrical properties of Cu2O:N thin films were investigated.The results showed that the as-deposited thin film grown at 300 ℃ substrate temperature contained only single phase of Cu2O under 12 sccm N2 flow rate.The RTA process had no influence on the crystalline structures of the as-deposited thin films in N2 atmosphere,but the crystalline quality of thin films could be sharply improved by rising annealing temperature(< 450 ℃).The thin film annealed at 400 ℃ showed good electrical properties-a Hall mo-bility(μ)of 27.8 cm2·V-1·s-1 and a resistivity(ρ)of 2.47×103 Ω·cm,which were attributed to the mitigated scattering of photo-generated carriers and the enhanced carriers transport,both induced by the improvement of crystalline quality and defect states of thin film as results of RTA.Our experiments indicated the effectiveness of low temperature sputtering deposition and RTA treatment on improving the photoelectric properties of Cu2O:N thin films.