Phase Diagram for the Pseudo-binary System Germanium and Gallium Arsenide

Abstract

not Available.

The Pseudobinary System Ge-GaAs

“…It should be noted that Glazov and Malyutina (1), Takeda et al (2), and this author agree quite well as to the eutectic composition (~ 16 mole % GaAs), temperatures of Takeda and this author are in fair agreement.…”

“…This test electrode was concentric to a polarizing electrode made of gold wire of about 1 cm 2 area. The reference electrode was a hydrogen saturated palladium wire (4 50 mv vs SHE) (2). The volume of the cell was approximately 10 ml.…”

Ge-related faceting and segregation during the growth of metastable (GaAs)1−x(Ge2)x alloy layers by metal–organic vapor-phase epitaxy

“…Although GaAs and Ge are size matched, they are mutually insoluble in the equilibrium bulk solid state, leading to almost complete phase separation into GaAs-and Gerich regions at all temperatures below the melting point. 4,5 The phase diagram is a simple eutectic with an invariant point at Ϸ15 mol % GaAs and Ϸ865°C. 4 The cause of this phase separation is related to the high energy that would be required to form Ga-Ge and As-Ge bonds, which do not satisfy the octet rule for valence electrons observed in the pure components, and the even higher energies predicted for As-As and Ga-Ga antisite bonds.…”

“…4,5 The phase diagram is a simple eutectic with an invariant point at Ϸ15 mol % GaAs and Ϸ865°C. 4 The cause of this phase separation is related to the high energy that would be required to form Ga-Ge and As-Ge bonds, which do not satisfy the octet rule for valence electrons observed in the pure components, and the even higher energies predicted for As-As and Ga-Ga antisite bonds. 5 Despite this strong tendency towards phase separation, relatively homogeneous epitaxial layers of metastable (GaAs) 1Ϫx (Ge 2 ) x alloys across the whole composition range have been reported, grown by nonequilibrium techniques such as metal-organic vaporphase epitaxy ͑MOVPE͒, 6,7 ion-beam-assisted sputter deposition, [8][9][10] and molecular beam epitaxy ͑MBE͒.…”

A Novel Route to Fibers with Incongruent and Volatile Crystalline Semiconductor Cores: GaAs

“…Ideally, once the melt cools and solidifies, the desired phase crystallizes separately from the flux phase. For GaAs, fluxes include Sn, Au, Ge, GaSb, and Cu. − The novelty of this work is combining the MCM for practicality of fiber fabrication with the flux melting and growth of crystalline phases that exhibit decomposition and therefore could not previously be fabricated using conventional molten core fiber processing. This “flux molten core method”, coupled with in-fiber traveling liquid zone growth using laser post-processing, opens the door to a wide variety of other optoelectronically useful core phases in fiber form.…”