Atomic layer deposition of GaN at low temperatures
Journal of Vacuum Science and Technology A
American Vacuum Society
Ozgit, C., Donmez, I., Alevli, M., & Biyikli, N. (2012). Atomic layer deposition of GaN at low temperatures. Journal of Vacuum Science & Technology A, 30(1), 01A124.
Please cite this item using this persistent URLhttp://hdl.handle.net/11693/12103
The authors report on the self-limiting growth of GaNthin films at low temperatures. Films were deposited on Si substrates by plasma-enhanced atomic layer deposition using trimethylgallium (TMG) and ammonia (NH3) as the group-III and -V precursors, respectively. GaNdeposition rate saturated at 185 °C for NH3 doses starting from 90 s. Atomic layer deposition temperature window was observed from 185 to ∼385 °C. Deposition rate, which is constant at ∼0.51 Å/cycle within the temperature range of 250 – 350 °C, increased slightly as the temperature decreased to 185 °C. In the bulk film, concentrations of Ga, N, and O were constant at ∼36.6, ∼43.9, and ∼19.5 at. %, respectively. C was detected only at the surface and no C impurities were found in the bulk film. High oxygen concentration in films was attributed to the oxygen impurities present in group-V precursor. High-resolution transmission electron microscopy studies revealed a microstructure consisting of small crystallites dispersed in an amorphous matrix.