Undoped GaAs grown by the vertical gradient freeze method: growth and properties

Technische Universität Bergakademie Freiberg, D-09596 Freiberg, Germany
Materials Science and Engineering B (Impact Factor: 2.17). 12/1994; 28(1-3):87-90. DOI: 10.1016/0921-5107(94)90022-1


Undoped GaAs crystals were grown by the vertical gradient freeze technique in a multizone furnace. By optimization of the growth equipment and the thermodynamic conditions, crystals were obtained with a low density of microdefects and dislocations (etch pits density about 10 3 cm -2) as well as semi-insulating behaviour. Residual impurities and defect levels were investigated by optical (local vibrational-mode and IR absorption) and Hall effect measurements.

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