InGaAs/InP quantum wells of widths varying from 19 Å to 150 Å have been grown by MOVPE and the growth temperature optimized using photoluminescence and SIMS. It was thus found that for a 78 Å well the lowest PL linewidth of 12.7 meV at 12 K was obtained for growth at 625°C. SIMS also showed sharpest interfaces for this temperature compared with growth at 610°C and 640°C. The well widths determined from PL energies were in good agreement with a growth rate of 8.25 Å/s. However, while the barrier widths of 150 Å were in agreement with SIMS results, the well widths from SIMS were found to be much larger, due to a lower sputtering rate of InGaAs compared with InP. Quantitative comparison was made assuming the presence of InAsP and InGaAsP interface layers on either side of the wells and the relative sputtering rates determined.

Semi-insulating < 111 > ZnTe prepared by In doping during Bridgman growth was found to have a resistivity of 5.74 × 10⁷ ohm-cm, the highest reported so far in ZnTe, with hole concentration of 2.4 × 10⁹/cm³ and hole mobility of 46 cm²/V.s at 300 K. The optical band gap was 2.06 eV at 293 K compared with 2.26 eV for undoped semiconducting ZnTe. Thermally stimulated current (TSC) studies revealed 2 trap levels at depths of 202–222 meV and 412–419 meV, respectively. Photoluminescence (PL) studies at 10 K showed strong peaks at 1.37 eV and 1.03 eV with a weak shoulder at 1.43 eV. Short anneal for 3 min at 250°C led to conversion to a 𝑝-type material with resistivity, 14.5 ohm-cm, indicating metastable behaviour. Raman studies carried out on undoped and In-doped samples showed small but significant differences. Possible models for semi-insulating behaviour and meta-stability are proposed.