Study of the optical and structural properties of GaN films grown on Si substrates with a SiC layer Conference Paper uri icon

abstract

  • GaN films were grown on Si(100) substrates by molecular beam epitaxy employing an RF activated N-plasma source. The substrates were coated with a thin SiC layer to reduce the reaction of N with Si. The substrate temperature was set at 750 °C, and the flux of Ga atoms was varied by changing the Ga-Knudsen cell temperature (TGa) from 950 to 1100 °C. The effects of the different growth conditions on the optical and structural characteristics of the films were studied by X-ray diffraction, atomic force microscopy, photoluminescence and photoreflectance spectroscopy. The results show that for TGa=950 °C, the films presented a very poor crystal quality with a mixture of hexagonal (α) and cubic (β) GaN phases. By increasing TGa the crystal quality improved. The films presented predominately the β-GaN phase for an optimal temperature TGa of 1050 °C. © 2003 Elsevier Science B.V. All rights reserved.

publication date

  • 2003-01-01