γ-LiAlO_2上a面ZnO薄膜的光谱特性研究

利用激光脉冲沉积(PLD)技术在(302)γ-LiAlO2衬底上成功生长了非极性的a面(1120)ZnO薄膜,光致发光谱(PL)带边发射峰半峰宽仅为115meV.研究了非极性ZnO薄膜光谱特性的面内各向异性,发现随着入射光偏振方向改变,在偏振透射光谱上,吸收边移动了20meV,这与A、B激子和C激子的能量差一致;而在拉曼光谱上,激发光偏振方向的改变导致E2模式的强度发生明显改变.

Nonpolar a-plane ZnO film was successfully grown on (302)gamma-LiAlO2 substrate by pulsed laser deposition. The temperature of substrate was 500 degrees C, the film was pure nonpolar a-plane ZnO. The FWHM of the peak of near band emission in the PL spectrum was found to be only 115 meV. Both polarized transmission spectra and polarized Raman spectra revealed the in-plane anisotropy of the nonpolar ZnO film by the shift of absorption edge and the change of intensity of Raman E-2 mode.