Recent Developments In The Growth Of Chalcopyrite Crystals For Nonlinear Infrared Applications

Abstract

Improvements in crystal growth technology have made it possible to grow crack- and twin-free boules of AgGaS2 and AgGaSe2 in comparatively large dimensions, AgGaS2 to 28 mm diameter by 100 mm length and AgGaSe2 to 37 mm diameter by 100 mm length. Although the crystals grow with optical defects (micrometer-size scattering centers), postgrowth heat treatment procedures have been used to successfully eliminate the defects and produce material of near-theoretical transparency. High optical quality, oriented single crystals of AgGaS2 1 cm in cross section and more than 2 cm in length and of AgGaSe, 1 cm in cross section and more than 3.5 cm in length have been produced and are leading to new advances in IR frequency generation. The optical and phase equilibrium studies as well as details of the crystal growth technology that led to this advance in materials technology are described.