High-quality metamorphic compositionally graded InGaAs buffers

Lee, Kenneth E.; Fitzgerald, Eugene A.

doi:10.1016/j.jcrysgro.2009.10.041

Cited by 47 publications

(34 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Lee and Fitzgerald [11] demonstrated up to X In ¼ 0.35 In x Ga 1 À x As graded buffers on on-axis (0 0 1) GaAs substrates with threading dislocation densityo9.5 Â 10 4 cm À 2 with a grading rate of 0.51% strain/mm. In both of their experiments, the In x Ga 1 À x As was grown on on-axis substrates at high temperatures (700-725 1C) to prevent the formation of phase separated regions.…”

Section: Results For Ingaas/ingap Graded Buffersmentioning

confidence: 99%

Compositionally-graded InGaAs–InGaP alloys and GaAsSb alloys for metamorphic InP on GaAs

Yang

Bulsara

Lee

et al. 2011

Journal of Crystal Growth

Self Cite

View full text Add to dashboard Cite

Section: Results For Ingaas/ingap Graded Buffersmentioning

confidence: 99%

Compositionally-graded InGaAs–InGaP alloys and GaAsSb alloys for metamorphic InP on GaAs

Yang

Bulsara

Lee

et al. 2011

Journal of Crystal Growth

Self Cite

View full text Add to dashboard Cite

“…When there is a 5% strain/expansion in the GaAs lattice parameter, the solubility of Bi increases by two orders of magnitude to about × . In practice, a larger substrate lattice parameter can be achieved through the use of a substrate such as InP or the use of graded or metamorphic buffer layers 56 . Note that we consider strains of up to 0.…”

Section: B Epitaxial Calculationsmentioning

confidence: 99%

Ab initiostudy of the strain dependent thermodynamics of Bi doping in GaAs

et al. 2012

View full text Add to dashboard Cite

The thermodynamics of Bi incorporation into bulk and epitaxial GaAs was studied using density functional theory (DFT) and anharmonic elasticity calculations. The equilibrium concentration of Bi was determined as a function of epitaxial strain state, temperature, and growth conditions. For a bulk, unstrained system, Bi in GaAs under typical growth conditions (Ga-rich and Bi-metal-rich at 400° C) has a dilute heat of solution of 572 meV/Bi and a solubility of , representing approximately a hundred times increase in solubility over the unstrained bulk case. Despite these potentially large increases in solubility, the equilibrium solubility is still very low compared to values that have been achieved experimentally through non-equilibrium growth. These values of solubility are also sensitive to choice of the Bi reference state. If the primary route for phase separation is the formation of GaBi within the same structure, rather than Bi metal, GaBi would serve as the source/sink for Bi. If GaBi is used as the Bi reference state, the epitaxial formation energy on a bulk unstrained GaAs substrate is reduced dramatically to 144 meV/Bi, yielding a Bi solubility of 0.083 x = in GaAs 1-x Bi x . These calculations suggest that Bi solubility could be greatly enhanced if Bi metal formation is inhibited and the system is forced to remain constrained to the GaAs 1-x Bi x structure. Although GaBi is not a naturally stable compound, it could potentially be stabilized through a combination of kinetic limitations and alloying.

show abstract

“…Recent advancements in metamorphic growth with compositionally graded buffers now allow Al x In 1Àx P to be grown directly on GaAs substrates with high crystal quality over a wide range of compositions. 10 Here, we explore a set of Al x In 1Àx P samples spanning the direct-indirect crossover to obtain exact values for the crossover composition and energy. A set of bulk Al x In 1Àx P samples closely lattice matched to InGaAs graded buffer layers were grown on GaAs substrates using MOCVD.…”

mentioning

confidence: 99%