Ge2 Sb2 Te5相变薄膜光学及擦除性能研究

利用蓝绿激光对非晶态Ge2Sb2Te5 相变薄膜进行擦除性能的研究,分别用1000 ns，500 ns，100 ns，60 ns脉宽的蓝绿激光进行实验.结果表明，一定脉宽下，反射率对比度随擦除功率的增加而增大.并且，在1000 ns，500 ns，100 ns，60 ns的激光作用时间范围内，非晶态薄膜均可转变成晶态.对于脉宽为60 ns的蓝绿激光，擦除功率大于4.49 mW以后，薄膜的反射率对比度高于15％，这表明Ge2Sb2Te5相变薄膜在短脉宽、低擦除功率条件下，可具有较高的晶化速度.同时，分析了非晶态和晶态Ge2Sb2Te5相变薄膜的光谱特性，对比研究了780 nm，650 nm，514 nm和405 nm波长处的反射率和反射率对比度，提出了Ge2Sb2Te5相变薄膜用于蓝光光盘的改进方法.

Study on the Optical Properties and Erasing Performance of Ge2Sb2Te5 Phase Change Thin Films

The erasing properties of amorphous Ge_2Sb_2Te_5 phase change films are studied by using blue-green laser. Blue-green lasers with 1000ns, 500ns, 100ns, and 60ns pulse duration are selected in the experiment. The results show that reflectivity contrast increases with the laser power increases. Within the time with 1000ns,500ns,100ns,60ns range, the amorphous films change to the crystalline phase. Erasing power higher than 4.49mW, the reflectivity contrast of films irradiation upon blue-green laser with 60ns is higher than 15%, which indicates Ge_2Sb_2Te_5 films have the high crystallization speed under the condition of short pulse duration and low erasing power. And also the optical spectra properties between amorphous and crystalline phases are analyzed. Compare to the reflectivity and the reflectivity contrast of amorphous and crystalline phases films at different wavelength with 780nm,650nm,514nm and 405nm, and present the future improving way to Ge_2Sb_2Te_5 films applied in the blue –ray disc.