Alternative boron precursors for BGaAs epitaxy

Metalorganic chemical-vapour-deposition (MOCVD) of InGaAs, BGaAs, and BInGaAs: Quantum chemical calculations on the mechanisms

“…However, the Z 2 removal has a high barrier (3.1 eV), which strongly reduces the deposition in comparison to BH 3 . This confirms the experimental finding that TMB does not result in significant boron incorporation into GaAs [6][7][8].…”

“…BGaAs and BInGaAs alloys [1][2][3][4][5][6][7][8][9][10][11][12] are candidates for application in multijunction solar cells and detectors. B x Ga 1Àx As with boron concentrations up to 4% is obtained by metalorganic chemical-vapour-deposition (MOCVD) or molecular-beam epitaxy (MBE).…”

“…Geisz et al [6][7][8] investigate the growth behaviour using various precursor molecules (diborane (B 2 H 6 ), trimethylboron (TMB), triethylboron (TEB), boron trifluoride (BF 3 )) under different pressures. TMB and BF 3 do not result in significant boron incorporation into GaAs.…”

Optimized growth of BGaAs by molecular beam epitaxy

“…Investigations of dilute B x Ga (1Àx) As and B x Al (1Àx) As alloys (with xp0:05) have been made on films grown via both MBE [3,4] and MOCVD [5,6]. For MOCVD systems, low growth temperatures and high As overpressures, as well as proper choice of B precursor gasses [7] are necessary for high-quality B x Ga (1Àx) As alloy growth. Boron incorporation in MBE systems has not been as successful as MOCVD growth experiments, with the most recent reports [3,4] indicating that boron incorporation on lattice sites was limited to mole fractions less than 0.01; higher B fluxes were reported to lead to antisite incorporation and dramatically increased surface roughness [3].…”

The band structures of BSb and B x Ga1−x Sb alloys

“…Compared to B x Ga 1−x As alloys, the small formation enthalpies for B x Ga 1−x Sb alloys indicate it may be easier to alloy boron in GaSb than in GaAs, though this comparison is only applicable to the degree that strain due to lattice mismatch is the dominating factor leading to poor crystalline quality in these two alloys. Presently in epitaxial growth experiments boron composition in B x Ga 1−x As to 7% is achievable [19] ; therefore, it is reasonable to conclude that 7% boron in GaSb may be possible.…”