Dislocation elimination in THM growth of GaAs

摘要: Abstract GaAs crystals 1 cm in diameter were grown by the Travelling Heater Method [111] Ga,111[111] As, 〈110〉 and 〈211〉 orientations. Etch pit densities on cross-sectional slices of 〈111〉 decreased exponentially with growth distance, while those longitudinal changed little distance. Equations derived for dislocation density versus distance two elimination mechanisms. It was concluded that dislocations probably eliminated growing out to surface due their propagation approximately normal toa convex interface. Some mutual annihilation may have occured first few millimeters growth, but this does not seem been predominant mechanism dislocations. Rapid removal ampoule from a hot furnace caused axial be generated portion cyrstals at temperature above about half melting point GaAS.