Atomic Layer Deposition Parameter Optimization

Al2O3 and SiO2 films were synthesized using Atomic Layer Deposition (ALD) at low temperature of 250 °C. Thermal ALD Al2O3 using Al (CH3)3 [trimethylaluminum (TMAl)] and H2O as precursors and plasma ALD Al2O3 using Al (CH3)3 [trimethylaluminum (TMAl)] and O2 plasma as precursor and oxidant, respectively. To grow SiO2 films Bis (diethylamido) silane as Si precursor and O2 plasma as oxidant were used. The growth process was characterized using ellipsometry. GPC (growth per cycle) of ~ 1.1 A was obtained in thermal and plasma ALD process to reach a self-limiting ALD growth. A refractive index of 1.65 and 1.45 were indicated for Al2O3 and SiO2 films, respectively. The results demonstrated an efficient ALD process with an excellent controlled thickness of films. An optimized recipe of the ALD process over the original recipes was obtained which corresponds well with similar experiments in literature. (Less)