Lateral epitaxial overgrowth of GaN films on sapphire and silicon substrates

Abstract

Coalescence overgrowth of GaN nanocolumns on sapphire with patterned metal organic vapor phase epitaxy Growth of single crystalline GaN thin films on Si(111) substrates by high vacuum metalorganic chemical vapor deposition using a single molecular precursor

Pendeo-Epitaxy versus Lateral Epitaxial Overgrowth of GaN: A Comparative Study via Finite Element Analysis

“…There are also stresses induced as a result of the thermal load during the complex cycle of heating±cooling±heating± cooling, applied during the stages of the selective GaN growth. [4,16]. The stresses generated as a result of the thermal mismatch in the heterostructures subjected to a temperature gradient are accommodated via bending and expansion or contraction of the structure.…”

Metalorganic chemical vapor phase epitaxy of gallium‐nitride on silicon

“…Kung and co-workers were the first to report on MOVPE grown ELOG on Si(111) [10]. They performed growth on a 200 nm thick GaN buffer on Si and obtained GaN free of pinholes and dislocations in the overgrown region.…”

“…by HVPE, many methods are known to reduce the dislocation density and the most often applied are based on masking and lateral overgrowth commonly known as ELOG or LEO [10] and pendeo epitaxy [11,12], all methods involving an ex-situ processing step before growth or after a first buffer layer has been grown. In-situ methods as Al(Ga)N/GaN superlattices [13] or AlN or Si x N y interlayers [14,15] are also suited to reduce the dislocation density without ex-situ processing.…”

Improvement of Structural Properties of GaN Pendeo-Epitaxial Layers

“…This anisotropy should be much lower in SiO 2 mask-removed Pendeo-epitaxial GaN layers. There have been reports on the dependence of strain anisotropy on thickness and lateral growth rate in typical LEO GaN layers [14]. XRD rocking curve measurement of the (0002) peak was taken along both the scattering plane perpendicular (f ¼ 90 ) and parallel (f ¼ 0 ) to the stripe direction for those Pendeoepitaxial GaN layers.…”

“…Despite these successful demonstrations in improved device performance on LEO GaN, some difficulties still remain in controlling the structural properties of the overgrown layer. For LEO GaN layers, threading dislocations at the seed (window) region and crystallographic tilt at the lateral overgrown region were typically observed [1,2,[12][13][14][15]. Pendeo-epitaxy with a dielectric mask, which is a new approach to the LEO technique, has been developed by employing a four to five times larger lateral growth rate of the regrown GaN from sidewalls of rectangular stripes compared with that of conventional LEO GaN layers [6,7].…”