Premium
Fabrication of freestanding 2″‐GaN wafers by hydride vapour phase epitaxy and self‐separation during cooldown
Author(s) -
Lipski Frank,
Wunderer Thomas,
Schwaiger Stephan,
Scholz Ferdinand
Publication year - 2010
Publication title -
physica status solidi (a)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.532
H-Index - 104
eISSN - 1862-6319
pISSN - 1862-6300
DOI - 10.1002/pssa.200983517
Subject(s) - materials science , wafer , epitaxy , metalorganic vapour phase epitaxy , optoelectronics , hydride , sapphire , fabrication , chemical vapor deposition , nanotechnology , optics , metal , metallurgy , laser , layer (electronics) , medicine , physics , alternative medicine , pathology
Using a dielectric mask, structured by optical lithography, freestanding 2″‐GaN wafers were prepared by hydride vapour phase epitaxy (HVPE) and self‐separation during cooldown. The mask was deposited on a GaN template grown on sapphire by metal organic vapour phase epitaxy (MOVPE) and it was shown that the instability of a SiN mask at growth temperature supports the further self‐separation. Testing different mask geometries, a hexagonally shaped pattern with a period of 30 µm and an opening of 3 µm showed best performance. This mask allowed the growth and separation of a full 2″ GaN wafer by utilizing the stress arising during cooldown from thermal mismatch to the substrate. Thickness inhomogenity was below 10% and the samples show good surface morphology.