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.