MOVPE GaN Grown on Alternative Substrates

Abstract

The structure, morphology and optical properties of GaN films deposited by metalorganic vapour phase epitaxy (MOVPE) on alternative substrates: ZnO, NdGaO, YSZ (yttria stabilized zirconia). Scanning electron microscopy, X‐ray diffraction and photoluminescence were used for the epitaxial layers characterisation. The obtained results have been compared to those of GaN layers grown on c‐plane sapphire substrates. It was established that the most important step towards the realisation of device quality GaN material on alternative substrates is the first stage of the growth process.

MOVPE growth of GaN around ZnO nanopillars

“…Furthermore, the growth of hollow GaN nanotubes [4] after in situ removal of ZnO nanopillars may offer an opportunity to realize novel 1D quantum structure devices for nano-photonics, nano-electronics, and biochemical sensing applications. Although some groups have reported successful growth of GaN on ZnO films by molecular beam epitaxy (MBE) [5] or pulsed laser deposition (PLD) [6], only a few groups have so far reported the growth of GaN on ZnO film by metalorganic vapor phase epitaxy (MOVPE) [7][8][9]. The major problem in the MOVPE growth of GaN on ZnO is the decomposition of ZnO after exposure to NH 3 and H 2 at temperatures in excess of 700 C. However, we have already reported in Ref.…”

Structure and optical properties of MOVPE and HVPE GaN films grown on GaN nanocrystalline powder substrate

“…Usually, GaN layers are grown on sapphire and SiC [1,2] or other alternative substrates [8] whose lattice constant is different from the lattice constant of GaN. In the case of such a heteroepitaxy, the quality of these layers is usually poor due to the large dislocation densities and deep levels inherited from the lattice mismatch between the GaN film and the substrate.…”

XPS characterisation of neodymium gallate wafers

“…New alternatives to sapphire, such as substrates of NdGaO 3 , have much better lattice matching (when cutting along relevant planes) and/or closer thermal expansion coefficients, so they are promising for epitaxial growth of the nitrides [10]. Neodymium gallate which is well known as a substrate for high temperature superconducting thin films was reported for the first time as a promising substrate for GaN epitaxial growth by Okazaki et al in 1997 [7].…”