Dr Tongtong Zhu
About
Due to the lack of lattice-matched substrates, heteroepitaxial GaN films grown on all crystal orientations suffer from very high defect densities. However, the defects and electrical properties in non- and semi-polar orientations are less well understood than for the more common c-plane.
As a member of the Cambridge Centre for Gallium Nitride, part of my research focuses on the investigation of unintentional doping and the impact of structural defects on the electrical and optical properties in GaN grown with different orientations using scanning capacitance microscopy and cathodoluminescence in the scanning electron microscope.
Optimize the growth of InGaN quantum dots within high quality optical micro-cavitiesMy objective is to develop and optimize the growth methods to facilitate the formation of high quality optical micro-cavities and to improve the performance of single photon sources based on InGaN quantum dots.I use a range of characterization techniques such as atomic force microscopy, X-ray diffraction, scanning electron microscopy to characterize the as-grown materials, and interact with collaborators in Oxford and at Harvard to develop devices from these materials