关键词: Ag_{11}In_{12}Te_{26}Sb_{51}, phase change, nonvolatile memory, resistance

Abstract: In this paper, Ag$_{11}$In$_{12}$Te$_{26}$Sb$_{51}$ phase change semiconductor films have been prepared by dc sputtering. The crystallization behaviour of amorphous Ag$_{11}$In$_{12}$Te$_{26}$Sb$_{51}$ thin films was investigated by using differential scanning calorimetry and x-ray diffraction. It was found that the crystallization temperature is about 483K and the melting temperature is 754.8K and the activation energy for crystallization, $E_{\rm a}$, is 2.07eV. The crystalline Ag$_{11}$In$_{12}$Te$_{26}$Sb$_{51}$ films were obtained using initializer. The initialization conditions have a great effect on the sheet resistance of Ag$_{11}$In$_{12}$Te$_{26}$Sb$_{51}$ films. We found that the effect of the initialization condition on the sheet resistance can be ascribed to the crystallinity of Ag$_{11}$In$_{12}$Te$_{26}$Sb$_{51}$ films. The sheet resistance of the amorphous ($R_{\rm amo}$) film is found to be larger than $1\times10^6\Omega$ and that of the crystalline ($R_{\rm cry}$) film lies in the range from about $10^3$ to $10^4\Omega$. So we have the ratio $R_{\rm amo}/R_{\rm cry}=10^2\sim 10^3$, which is sufficiently large for application in memory devices.

Key words: Ag$_{11}$In$_{12}$Te$_{26}$Sb$_{51}$, phase change, nonvolatile memory, resistance