Boule-like growth of GaN by HVPE

Published in:
phys. stat. sol. (c), vol. 7, no. 1, pp. 28-31 (2010).
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Abstract:
GaN substrates are indispensable for fabrication of blue laser diodes. Growth and cutting of HVPE grown GaN boules is currently the most promising route for cost-efficient supply of 2 inch c-plane substrates. But boule lengths and growth rates are still rather low constricted by formation of cracks and morphological defects (V-pits). It is shown here that the formation of morphological defects in HVPE depends on the growth conditions. The control of their formation allows for high growth rates of about 500 µm/h with improving material quality during growth. Using optimized growth parameters a threading dislocation density of 3x10⁶ cm^-2 and narrow line widths below 100 arcsec of x-ray rocking curves were obtained for a 3 mm thick GaN layer grown on a GaN/sapphire template.

PACS:
61.72.Ff, 81.05.Ea, 81.15.Kk

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