Evidence of Be3P2 formation during growth of Be-doped phosphorus-based semiconductor compounds

Abstract

In this work, we present evidence that Be3P2 microcrystals are formed in Be-doped phosphorus-based semiconductor compounds grown by chemical beam epitaxy. Our results suggest that microcrystal formation occurs when high Be concentrations (>1018 cm−3) and temperatures higher than 500 °C are used for crystal growth. The main consequence of Be3P2 formation is a high phosphorus consumption close to these microcrystals that causes a large density of P vacancies in the semiconductor layer. This results in reduced electrical mobility, lattice parameter reduction, and poor crystalinity of the film in general.

Laser reflectometryin situmonitoring structural and growth effects on the electron cyclotron resonance etching of In0.49Ga0.51P layers in Al-free laser structures

“…11,12 In our system, to reduce the cluster formation and obtain proper doping, In 0.49 Ga 0.51 P must be grown at 500°C. Above this temperature Be doping becomes very inefficient and structural changes are observed due to the Be 3 P 2 formation.…”

Strong spatial beryllium doping selectivity on InGaP layers grown on pre-patterned GaAs substrates by chemical beam epitaxy

“…Specifically for CBE, the behavior of Be is not well understood. For large impurity concentration and for the growth over (0 0 1) planar substrates, beryllium causes surface degradation [3,4] and, at least for phosphorus compounds, a small reduction in lattice parameter is observed [5], that is shown to be related to the formation of Be 3 P 2 clusters [6]. Also, a reduction in beryllium doping efficiency is observed as the growth temperature increases from 500 C to 540 C. Associated with the reduction in beryllium doping efficiency, it is always observed surface morphology degradation by atomic force microscopy and a direct relationship to an increased electrochemical etching pit density [7].…”

First-Principles Study of High-Pressure Phase Stability and Electron Properties of Be-P Compounds

“…Regarding the tetragonal structure of Be 3 P 2 , based on structural refinements of X-ray and neutron diffraction data, Elmaslout reported lattice constants and structure factors [ 22 ]. According to Carvalho et al, Be 3 P 2 microcrystals arise in Be-doped phosphorus-based semiconductor compounds generated by CBE (chemical beam epitaxy) in Be-rich environments and at temperatures over 500 °C [ 23 ]. Nevertheless, for semiconductor applications, high pressure phases are paramount.…”