Characterization of native dislocations in chalcopyrite AgGaS2 by X-ray topography

The structural defects in annealed chalcopyrite AgGaS2 single crystals grown by the vertical gradient freezing method were investigated using X-ray topography. Dislocations with Burgers vector of the type b = 1/2[<(11)over bar 1>] moving {112}, b = [001] on {010} and b = [100] on {010} were identified within the crystals, as distinct from the preferential activation of b = 1/2[<(3)over bar 11>] dislocations on {112} in the related compound CuFeS2. Twins formed due to the motion of dislocations with pure screw character of b = 1/6[11(1) over bar] on {112} were also observed as similarly found for CuFeS2.