Temperature influence on the growth of gallium nitride by HVPE in a mixed H2/N2 carrier gas

Growth of thick GaN layers with hydride vapour phase epitaxy

“…We have used a separate limited HCl flow directed towards the outlet of the GaCl tube. This will counteract growth of GaN on the outlet tube, without seriously disturbing the growth on the remote substrate [7]. A separate H 2 flow on the GaCl outlet has a similar effect, but may affect the growth on the substrate in an unwanted manner (e.g.…”

Crystal growth of GaN on (0001) face by HVPE: Ab initio simulations

“…The thermodynamics of the HVPE growth has been studied extensively [11][12][13][14][15][16][17]. It has been established that gallium is transported predominantly by GaCl where the HCl to GaCl conversion ratio is as high as 90% [18].…”

Low-cost high-quality GaN by one-step growth

“…In this reactor configuration where the chlorides and hydrides are separately produced, then mixed homogeneously upstream the substrate, the experimental conditions are controlled. These well-defined conditions are used to compute the expected growth rate according to the theoretical model widely described in previous papers [22][23][24]. This phenomenological model is based on the thermodynamic and kinetic analysis and takes into account a growth mechanism involving the chlorine desorption by GaCl as GaCl 2 and an etching reaction by HCl.…”

“…The H 2 ratio in the (N 2 +H 2 ) total carrier gas labelled RH 2 was varied from 0 (no H 2 ) to 1 (full H 2 carrier gas). In these experimental conditions, the kinetic process is mainly governed by the GaCl 2 -HCl mechanism corresponding to a negative value of the classical supersaturation of the vapour phase, thus to an expected etching of the substrate by the HCl [22][23][24]. A study was then carried out on heavily dense substrates presenting a dielectric mask with 1-mm-wide open stripes every 1.5 and 3 mm, 2-mm-wide every 2.5 and 5 mm, and 5-mm-wide every 5.5 and 10 mm.…”