激光致晶态Ge2Sb2Te5相变介质的光学常数

利用椭偏仪和光谱仪研究了结晶程度对Ge2Sb2Te5相变薄膜光学常数的影响.当初始化仪转速固定时,随激光功率的增加,折射率基本随之减小,消光系数逐渐增大,透过率逐渐减小;当激光功率固定时,随转速的增大,折射率也随之增大,消光系数随之减小,透过率逐渐增加.非晶态与晶态间的变换、薄膜微结构的变化(包括原子间键合状态的变化)以及薄膜内残余应力是影响Ge2Sb2Te5相变薄膜复数折射率的主要原因.测量了CD-RW(可擦重写光盘)中Ge2Sb2Te5薄膜非晶态和晶态的反射率.

Optical Constants of Laser-Induced Crystalline Ge2Sb2Te5 Phase-Change Media

The effects of crystallization fraction on the op ti cal constants of Ge_2Sb_2Te_5 phase-change films are studied using spectros copic ellipsometer and spectrometer.With fixed initialization velocity,the refra ctive index and transmissivity decrease while the extinction coefficient increas es when the laser power increases.With fixed initialization laser power,the refr active index and transmissivity increase and the extinction coefficient decrease s when the initialization velocity increases.The change between amorphous phase and crystalline phase,the changes in microstructure (including change in bonding state) and the internal residual stresses in film are the main factors that aff ect the complex refractive index of Ge_2Sb_2Te_5 phase-change film.The refle ction spectra of the Ge_2Sb_2Te_5 film in CD-RW (compact disk rewritable) ph ase-change optical disk at amorphous and crystalline states are also measured.