Here, we present homogeneous, wurtzite InN layers epitaxially-grown on on-axis 4H-SiC (0001) by ALD. 4H-SiC possess type-I band alignment with respect to InN which could be a promising substrate to initiate the InN heterojunctions for device applications. The growth of InN is done by ALD at 320 °C and 6 mbar in a Picosun ALD system as previously described in detail. Trimethyl indium (TMI) and (NH3 + Ar + N2) plasma were used to provide In and N respectively for complete reaction of InN. Double-side polished with Si-face chemicalmechanical-polished, on-axis 4H-SiC (0001) substrate used in this work was commercially acquired in test grade from Norstel AB. The 4H-SiC (0001) substrate was chemically cleaned using standard RCA cleaning procedure before loading into the reactor. After stabilization at 320°C for 60 min and prior to the growth of InN, the 4H-SiC (0001) substrate was subjected to (Ar + N2) plasma treatment for 2 minutes to remove residual surface oxide. After the plasma treatment, the system was purged with 100 sccm N2 for 10 sec followed by the first TMI pulse.