Epitaxial Growth of Thick Polar and Semipolar InN Films on Yttria-Stabilized Zirconia Using Pulsed Sputtering Deposition

We grew thick InN films on yttria-stabilized zirconia (YSZ) substrates by high-growth-rate pulsed sputtering deposition. X-ray diffraction analysis revealed that the in-plane orientation distribution of the InN (0001) films on YSZ decreased as the film thickness increased. The edge dislocation density of the 9.0-mu m-thick InN film grown at a rate of 6 mu mh(-1) is calculated to be 1.7x10(9)cm(-2), and the atomically flat surface exhibited a step-and-terrace structure. In addition, the crystallinity of semipolar InN is improved by increasing the film thickness. These results indicate that high-growth-rate pulsed sputtering deposition can be used to prepare InN substrates for the fabrication of high-speed electron devices and InGaN-based, long-wavelength light-emitting devices.