Electron backscattered diffraction patterns from cooled gallium nitride thin films

The acquisition of electron backscattered diffraction (EBSD) (or Kikuchi diffraction) patterns in the scanning electron microscope is proving to be a useful technique with which to probe the structural properties of nitride thin films. In this paper we show that if a sample is cooled the patterns improve dramatically, an increase in intensity of the Kikuchi lines and a decrease in the intensity of the diffuse background is observed. Kikuchi lines from higher order planes become visible and the HOLZ rings become better defined. Such cooled patterns yield more information on the sample, particularly on non-centrosymmetric planes, from which the polarity of the nitride thin film under investigation may be deduced.