Author/Authors :
Valcheva، نويسنده , , E and Paskova، نويسنده , , T and Abrashev، نويسنده , , M.V and Persson، نويسنده , , P.إ.O and Paskov، نويسنده , , P.P and Goldys، نويسنده , , E.M and Beccard، نويسنده , , R and Heuken، نويسنده , , M and Monemar، نويسنده , , B، نويسنده ,
Abstract :
Thick HVPE-GaN layers are grown on Si-doped and undoped MOCVD-GaN ‘template’ layers as well as directly on sapphire, with the aim to investigate the effect of the MOCVD template on the strain relaxation and spatial distribution of free carriers in the overgrown HVPE films. Spatially resolved cross-sectional micro-Raman measurements, cathodoluminescence and transmission electron microscopy show improved crystalline quality resulting in elimination of the non-uniformities of electron distribution, a low free carrier concentration (<1017 cm−3) as well as a significant strain relaxation effect.
Keywords :
HVPE , strain , GaN , Doping distribution
