High temperature limitations for GaN growth by RF‐plasma assisted molecular beam epitaxy: Effects of active nitrogen species, surface polarity, and excess Ga‐overpressure

Abstract

Growth of GaN by molecular beam epitaxy is limited by reduced growth rate related to thermal decomposition. Factors influencing thermal decomposition are growth species (atomic versus metastable molecular nitrogen), surface polarity (N-vs. Ga-polar), and varying Ga-overpressure. Surface polarity and growth species are the predominant influence determining the onset of thermal decomposition. A significant Gaoverpressure can suppress decomposition, allowing an increase in growth temperatures. Electrical properties are strongly influenced by Ga-overpressure and thermal decomposition.

Catalyst-Free Gan Nanowires as Nanoscale Light Emitters

“…For normal nanowire growth conditions, the polarity of the GaN growth follows that of the underlying AlN buffer layer (if present). Because polarity can affect the growth rate (more precisely, the decomposition rate under [VanMil et al, 2005]), it appears that growth of Ga-polar material occurs on and is defined by underlying Al-polar domains. Because AlN buffer layer polarity is a complex function of N:Al ratio, substrate temperature, and Al pre-layer types, the ability to measure this polarity with piezoresponse force microscopy has been an important growth characterization tool.…”

“…For normal nanowire growth conditions, the polarity of the GaN growth follows that of the underlying AlN buffer layer (if present). Because polarity can affect the growth rate (more preci atomic N flux [VanMil et al, 2005] on and is defined by underlying Al complex function of N:Al ratio, substrate t to measure this polarity with piezoresponse force microscopy has been an important growth characterization tool. the V:III ratio during the nucleation process, longer, thinner nanowires form instead.…”

Studies on plasma assisted molecular beam epitaxial growth of GaN-based multilayer heterostructures on Si for photodetector application

“…As described by Vanmil et al [29], the GaN decomposition occurs when the growth temperature is higher than 750 ºC. When using metastable N2 molecular species, the thermal decomposition rate decreases a lot.…”