Top-view SEM of the GaN film on SiC deposited at 250  C composed of larger grains compared to GaN on Si substrate, Figure . Finally, a thermal ALD route to GaN was investigated using 1 and NH3 without plasma discharge. The same pulse parameters were used as the plasma process, but a 16 s of NH3 pulse was used in a temperature range of 150-400  C. GaN films could be obtained also via this thermal process, however, the films were X-ray (-2 and GIXRD) amorphous. The XPS analysis showed the films contained high amounts of C and O impurities, 4 at.% and 15 at.%, respectively (Figure ). The Ga/N ratio could not be accurately be measured due to the Ga