氧氩流量比对氧化铋纳米薄膜微结构及光电性能的影响研究

Influence of the flow ratio of oxygen to argon on Microstructure and Photoelectric properties of bismuth oxide nano-films

为了制备出不同光电性能的氧化铋薄膜,并明晰其性能机理,以便后续研究与氧化锌薄膜复合成压敏薄膜。采用磁控溅射法,改变溅射气氛中氧气和氩气的流量比,在玻璃衬底上制备出了三个氧化铋薄膜样品,并对其微观形貌、结构及光电性能进行了测试分析。结果表明:溅射气氛中的氧氩流量比对薄膜微结构及光电性能影响显著;不同氧氩流量比制备的Bi_(2)O_(3)薄膜中均含BiO_(2)和Bi杂相,且随着氧氩流量比由0∶40增大至4∶36,薄膜中Bi含量减少,BiO_(2)增加;薄膜颜色由黑变黄;沉积速率由14 nm/min减少至12 nm/min;晶粒尺寸增大,表面趋向致密均匀,可见光区透过率由0.25%增加到56.73%;禁带宽度由0增加到3.17 eV;载流子浓度、导电性能急剧降低,调节溅射气氛中氧氩流量比可有效控制氧化铋薄膜的禁带宽度,载流子浓度等,从而获得不同光电性能的薄膜样品。

In order to prepare high-quality bismuth oxide thin films and clarify the formation mechanism of their properties for the subsequent research on the low voltage varistor film compounded with ZnO film,three samples of bismuth oxide thin films with different flow ratios of oxygen to argon were prepared on common glass substrates by magnetron sputtering.And the microstructure,optical and electrical properties of the samples were tested and analyzed.The test results show that:①the flow ratio of oxygen to argon in the sputtering atmosphere has a significant effect on the microstructure and photoelectric properties of Bi_(2)O_(3) films;②all the Bi_(2)O_(3) films prepared with different flow ratios of oxygen to argon contain BiO_(2) and Bi impurities;③the Bi decreases and BiO_(2) increases with the flow ratio increase;④the color of the film changes from black to yellow;⑤the deposition rate decreased from 14nm/min to 12nm/min;⑥the grain size increases and the surface tends to be more dense and uniform,the transmittance of visible light region increased from 0.25%to 56.73%,and the band gap width increased from 0 to 3.17eV;⑦the carrier concentration and conductivity decrease sharply with the flow ratio increase.It can be seen that adjusting the flow ratio of oxygen and argon in the sputtering atmosphere can effectively control the band gap width and carrier concentration,so as to obtain the film samples with different photoelectric properties.