Effect of crystal orientation on the implant profile of 60 keV Al into 4H-SiC crystals

4H-SiC wafers of orientations (0001) and (112̄0) were implanted with 60 keV Al− in different major axial, planar, and low symmetry (“random”) directions to ascertain the degree of channeling and to determine the optimum tilt conditions for ion implantation. Significant channeling was observed for all axial directions with the [112̄0] channel exhibiting the deepest channeling with a maximum penetration depth 45 times greater than the projected range of the random implants. Significant channeling was observed for the {112̄0} and especially the {0001} planar channels while the implants in the {101̄0} planar channels did not differ from the corresponding random implants. To minimize channeling in (0001) crystals, our results show that beam alignment normal to the surface is advisable for off-axis (0001) wafers with the miscut toward 〈112̄0〉, while tilting of the wafer is necessary when the miscut is toward 〈101̄0〉. For the (112̄0) material, channeling can be minimized by a tilt of ≳10° toward the [0001] direction.