Lattice spacing measurements around dislocations in an undoped GaAs crystal grown by the liquid-encapsulated Czochralski method

Abstract

Abstract The lattice spacing in a cellular structure of an undoped liquid-encapsulated Czochralski GaAs crystal has been measured by synchrotron X-ray topography with a (+n, −n, +n) triple-crystal system. Distinguishable lattice spacing variations were observed in dislocation-related regions. One region, neighbouring to the cell walls, shows a small lattice spacing compared with the average value. Another region, where dislocations intersect with the crystal surface inside the cell, shows a large lattice spacing. The lattice spacing variation depends on the dislocation features.