A Picosun R-200 ALD system was employed to grow InN films using trimethyl indium, In(CH3)3 (TMI) and plasma discharged NH3/Ar gas mixture. A detailed process development can be found in our earlier work. In this work, 4H-SiC (0001) was used as the substrate, which allows epitaxial growth of InN. The samples are loaded in the system without a load lock chamber. The plasma is generated within a quartz tube surrounded by a cylindrical RF coil. The heated substrate holder is located approximately 70 cm below the plasma source. N2 (99.999 % and further purified by a getter filter) was used as purge gas in the system and as carrier gas for the TMI (Pegasus Chemicals, Alpha grade). As previously described, a fillempty pulsing scheme was used to get a sufficient flow of TMI in to the deposition chamber. The NH3 plasma was ignited using a mixture of 50 sccm NH3 (99.9990 % and further dried with a getter filter) and 100 sccm Ar (99.9997 % and further purified with a getter filter). The applied rf power for the NH3 plasma is 2800W. Prior to the deposition of InN, the substrates were subjected to a 2-minute plasma exposure (2800W) with a 100 sccm Ar + 50 sccm N2 plasma gas mixture, followed by 550 InN ALD cycle after a 10 s N2 purge. The InN ALD cycle comprises 4 s TMI pulse, 10 s N2 purge, 12 s plasma exposure using 50 sccm NH3 + 100 sccm Ar and 2800 W, and 6 s N2 purge. The deposition temperatures were between 250 and 450 °C while the pressure was kept at 6 mbar for all growth runs. A small pressure fluctuation jumping from 6 mbar to 10 mbar was observed while the TMI pulse is being introduced into the chamber.