SEM cross section view of lateral overgrown GaN following the two step process. The sample was not metallized in order to observe resistivity contrast between (1) undoped (dark gray) and (2) Mg doped (light gray) GaN. In (1) a peaky surface as in figure 6 is obtained, the dashed line was drawn as a guide for the eye. In (2) the top C facets have reappeared and expand following the arrows. Note that voids are created in the deep valley of (1) during (2) mainly due to diffusion limited growth.
© 1998 The Materials Research Society
