Influence of Growth Conditions and Doping on Physical Properties of Gallium Antimonide Single Crystals

Gallium antimonide (GaSb) single crystals were grown by modified Czochralski method integrated with in situ synthesis in a flowing atmosphere of pure hydrogen. The influence of charge material purity as well as other technological parameters on GaSb crystals quality was investigated. High purity undoped GaSb single crystals were grown with residual acceptors concentration < 1.4 × $10^{17} cm^{-3}$ and high mobility ≈ 690 $cm^2$/Vs (at 300 K). P-type GaSb crystals were doped with silicon (carrier concentration up to 2 × $10^{19} cm^{-3}$) and with zinc (up to 1 × $10^{19} cm^{-3}$). Tellurium doped n-type GaSb single crystals were obtained with concentration up to 2 × $10^{18} cm^{-3}$. Electrical parameters were investigated by the Hall measurements (300 K and 77 K). Temperature dependent Hall measurements (10 ÷ 300 K) were used to compare the quality of undoped GaSb (obtained from Sb of different purity). Dopant concentration was estimated by glow discharge mass spectroscopy analysis. Axial and radial distribution of carrier concentration were investigated especially for Te-doped crystals (low segregation coefficient of Te in GaSb). Great contribution of compensation and self-compensation mechanisms is shown especially for the beginning part of grown crystals and for low Te-doping level. Radial distribution of physical properties for crystals grown in 〈100〉 direction is not axisymmetrical especially for doped GaSb crystals.