Direct growth of freestanding GaN on C-face SiC by HVPE

Direct growth of freestanding GaN on C-face SiC by HVPE

In this work, high quality GaN crystal was successfully grown on C-face 6H-SiC by HVPE using a two steps growth process. Due to the small interaction stress between the GaN and the SiC substrate, the GaN was self-separated from the SiC substrate even with a small thickness of about 100 μm. Moreover, the SiC substrate was excellent without damage after the whole process so that it can be repeate...

Influence of stress in GaN crystals grown by HVPE on MOCVD-GaN/6H-SiC substrate

GaN crystals without cracks were successfully grown on a MOCVD-GaN/6H-SiC (MGS) substrate with a low V/III ratio of 20 at initial growth. With a high V/III ratio of 80 at initial growth, opaque GaN polycrystals were obtained. The structural analysis and optical characterization reveal that stress has a great influence on the growth of the epitaxial films. An atomic level model is used to explai...

HVPE Growth on MOVPE-Grown Semipolar (112̄2) GaN 75 HVPE Growth on MOVPE-Grown Semipolar (112̄2) GaN

For the GaN material system, one reason for the breaking down of the efficiency is the socalled quantum confined Stark effect (QCSE). Since today’s LEDs are grown in the common [0001] (c-)direction, the internal polarization fields are perpendicular to the quantum wells. The cause of these internal fields are spontaneous and piezoelectric polarization. The reason for the latter is mechanical st...

Growth of GaN on porous SiC by molecular beam epitaxy

Growth of GaN on SiC(0001) by Molecular Beam Epitaxy

GaN films are grown by plasma-assisted molecular beam epitaxy on 6H-SiC(0001) substrates. Suitable substrate preparation and growth conditions are found which greatly improve the structural quality of the films. Threading dislocation densities of about 1 10 cm for edge dislocations and 1 10 cm for screw dislocations are achieved in GaN films of 1 m thickness grown under optimal conditions. Reve...