Activation energy of AgInSbTe film through isothermal sheet resistance measurements

RF sputtering was used to deposit AgInSbTe (AIST) films on silicon substrates. The as-deposited amorphous films were crystallized at temperatures above 413 K and the sheet resistance change was used to characterize the degree of crystallization and the associate activation energy in this study. The sheet resistance of amorphous films quickly decreased when the crystallization was initiated and reached a steady lower value with the IOC index of around 0.7, which means 70% crystallization. The kinetics of sheet resistance change was researched isothermally in an argon atmosphere and compared to the results of DSC measurement with constant heating rates. It was found that activation energy, 0.82eV. obtained from isothermal sheet resistance measurement was rather close to that. 0.92eV, obtained from DSC measurement. The Avrami exponent was determined to be 1.1-1.4 in isothermal sheet resistance measurement. A lower Avrami exponent implied that impingement effects possibly resulted in the sheet resistance decreasing with about 78% crystallization of amorphous films.