Ea. Stach et al., Structural and chemical characterization of free-standing GaN films separated from sapphire substrates by laser lift-off, APPL PHYS L, 77(12), 2000, pp. 1819-1821
Laser lift-off of GaN heteroepitaxial layers from sapphire substrates is a
promising method for electronic device integration and GaN substrate creati
on. Of critical importance is the structural and chemical quality of the Ga
N layers following laser processing. In this letter, transmission electron
microscopy techniques are used to characterize the modifications that occur
at the resulting GaN surfaces. Structural alteration and chemical intermix
ing following lift-off are confined to approximately the first 50 nm. These
results indicate that laser lift-off is a viable route for GaN substrate c
reation, as well as for electronic device integration. (C) 2000 American In
stitute of Physics. [S0003-6951(00)03337-4].