Optical Constants of Laser-Induced Crystalline Ge2Sb2Te5 Phase-Change Media
激光致晶态Ge_2Sb_2Te_5相变介质的光学常数

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.