Crystallization behavior of Si-added amorphous Ga19Sb81 films for phase-change memory

Crystallization behavior of Si-added amorphous Ga19Sb81 films was studied by measuring electrical resistance (R) versus temperature (T) at various heating rates. The crystallization temperatures obtained from the R-T curves increase from 228 to 284 °C measured at the heating rate 10 °C/min with increasing Si content to 14 at.%. All films with full-crystallization show phases of Sb and GaSb. At 9 at.% Si the activation energy of crystallization and the rate factor reach the maxima of 9.1 eV and 6.8 × 1084 min− 1, respectively. The kinetic exponent (n) of the film with 9 at.% Si is below 1.5 which indicates growth-dominated crystallization, while that of other films falls in 1.5 ≤ n ≤ 2.5 which denotes decreasing nucleation rate during nuclei growth. Time of 90% crystallization slightly decreases owing to Si addition as estimated using JMA theory. The temperature corresponding to 10-year failure-time obtained through isothermal Arrhenius plot effectively increases from 156 to 217 °C as Si content is from 0 to 14 at.%. The melting temperature slightly reduces from 591 to 581 °C with Si addition. The reset voltage of test cells based on Si4(Ga19Sb81)96 is reduced by 0.5 V to ~ 2.75 V and can be set-reset switched within pulse-widths of 40-200 ns.