Parameter window of diamond growth on GaN films by microwave plasma chemical vapor deposition

We report here, a detailed study of the parameter window of the deposition pressures to grow the diamond films on GaN coated quartz substrates using microwave plasma deposition technique. Hexagonal GaN films of 5 µm coated on quartz are used as substrates for diamond deposition in the pressure range of 80–140 Torr, using microwave plasma chemical vapor deposition (MPCVD) technique. The diamond films are characterized by scanning electron microscopy, XRD, photoluminescence and Raman spectroscopy. Scanning electron microscope image shows that the nucleation density of the films is high and we can deposit a continuous film for a deposition time ranging for 6–8 h. Oriented growth of diamond has been observed at higher pressure.