真空退火和氢退火对ZnO：B薄膜电学和光学性能的影响

Effect of Vacuum and Hydrogen Annealing on the Electrical and Optical Properties of ZnO∶ B Thin Films

在玻璃衬底上采用低压化学气相沉积法制备了B掺杂的ZnO薄膜,研究了真空气氛和氢气气氛下不同退火温度对ZnO∶B(BZO)薄膜电学性能和光学性能的影响。结果表明,两种不同退火气氛下进行退火处理,BZO薄膜性能发生相反的变化:真空气氛下退火时,BZO薄膜的导电能力随退火温度的提高而下降,但长波区的透光率却随之增加,这主要是由于真空退火后载流子浓度降低所致;而在氢气气氛下退火后,BZO薄膜载流子浓度基本保持不变,但Hall迁移率却显著提高,从而在保证透光率基本不变的前提下,使得BZO薄膜的导电能力得到显著提高,这可以为BZO薄膜光学和电学综合性能的协同优化提供一种有效方法。

B doped ZnO （BZO） thin films were fabricated on glass substrates by LPCVD method. The effects of vacuum and hydrogen atmosphere annealing on the optical and electrical properties of BZO thin films were studied respectively. The results show that the two thermal treatments in vacuum and hydrogen atmosphere lead to reverse effects on optical and electric properties of BZO thin films. After vacuum annealing, the electrical conductivity of BZO thin films decreased with annealing temperature increasing and the total transmission of BZO thin films increased over long-wavelength range due to reduction of carrier concentration. On the contrary, after a post thermal treatment in hydrogen atmosphere, the electrical conductivity of the BZO films was obviously improved, simultaneously keeping the transmittance almost the same, which may be attributed to a dramatic increase of carrier mobility. This hydrogen annealing should provide a method for further improving the optical and electrical properties of BZO thin films.