Characterization of undoped and Te-doped GaSb crystals grown by the vertical feeding method

Solidification features of cast and vertically fed Te-doped GaSb materials

“…Previously published results [12] have shown that undoped samples exhibited an almost monocrystalline behaviour while Te-doped samples were highly polycrystalline and showed an inverted solute profile along the vertical axis in comparison with classical bulk growth techniques. This behaviour was attributed to a decrease of the segregation coefficient (k) due to a reduction of the overall growing rate during the solidification.…”

“…The VFM set-up developed in our laboratory as well as the routine used for undoped and Te-doped GaSb experiments have been previously described [12]. Briefly, it consists of a two separated vertical crucibles set-up placed in a two-zone furnace, where the temperature of each zone is controlled independently.…”

Technical Developments and Principal Results of Vertical Feeding Method for GaSb and GaInSb Alloys

“…The electrical characteristics obtained by Hall measurements at room temperature [12] showed that LC-Un samples exhibits a p-type conduction, with a carrier density (p) of 3·10 17 cm -3 , a resistivity (ρ) of about 0.07 Ω·cm and a mobility (μ) of about 300 cm 2 ·V -1 ·s -1 . In the case of LFeed-Te samples, measurements showed a n-type conduction with a carrier density of 1·10 18 cm -3 , a resistivity of about 0.0038 Ω.cm and a mobility of 1500 cm 2 ·V -1 ·s -1 .…”

“…In the case of the VFM, experiments performed with the Low Casting configuration for undoped and Te-doped GaSb [12] showed that for undoped materials (LC-Un), the samples were almost monocrystallines while Te-doped samples (LC-Te) showed a high degree of polycrystallinity with nearly all the orientation expected for GaSb appearing on the XRD spectra. In addition, the segregation profile along vertical axis of Te-doped materials showed an inverted profile in comparison with the Scheil law.…”

“…The luminescence properties were studied through Cathodoluminescence at 80 K following the procedure of Ref. [12]. The spectral distribution of the CL emission of both LC-Un and LFeed-Te samples showed a quite homogenous spatial luminescence.…”