Figure 1From: Nanoscratch Characterization of GaN Epilayers on c- and a-Axis Sapphire Substrates3D AFM images of scratch tracks formed in GaN films on sapphire substrates: a 2,000 μN ramped force, c-axis sapphire; b 4,000 μN, c-axis sapphire; c 2,000 μN, a-axis sapphire; d 4,000 μN, a-axis sapphireBack to article page