退火温度对Ga掺杂SnO2薄膜结构和光致发光特性的影响

Influences of Annealing Temperature on the Structure and Photoluminescence Properties of Ga-doped SnO2 Thin Films

摘要:

利用电子束蒸镀在石英玻璃上制备出Ga掺杂的SnO2(SnO2∶Ga)薄膜。结合X射线衍射仪、原子力显微镜、紫外-可见-近红外分光光度计和光致发光谱,研究了不同退火温度对薄膜的结构与发光特性的影响。研究结果表明:当退火温度超过500℃,薄膜呈现四方金红石结构,随着退火温度的提高,晶粒尺寸增大,薄膜的禁带宽度变宽,发光强度逐渐增加,成功制备出发蓝紫光的SnO2∶Ga薄膜。薄膜样品在700℃下退火后光致发光强度显著增强,这是因为随着退火温度的升高,SnO2∶Ga薄膜的非辐射中心减少,有利于发生辐射复合。

Abstract:

Ga-doped SnO2 thin films were produced on quartz glass substrates by E-beam evaporation. X-ray diffraction, atomic force microscope (AFM), UV-Vis-NIR spectrophotometer and photoluminescence spectroscopy were used to investigate the influences of annealing temperature on the structure and photoluminescence properties of Ga-doped SnO2 thin films. It’s found that with increasing the annealing temperature, the size of grains becomes bigger, the band gap becomes wider and the intensity of photoluminescence increases. The results show that blue-purple light emitting SnO2∶Ga thin films were manufactured successfully and the remarkable photoluminescence of the SnO2∶Ga thin film annealed at 700℃ is attributed to removal of non-radiative centers at higher temperature.