Effects of Substrate Surface Treatments on the Defect Incorporation in Hydride VPE Grown InGaAs Films.

摘要

The quality of the InP substrate surface was investigated, and it was shown that the substrate surface and the surface of the films grown on them is smoother when the substrate is etched in situ with an HC1 etch than when it is bathed in PH3. The in situ etch also improves the mobility and decreases the background carrier concentration. Other surface studies show that a too large III/V ratio leads to hillock formation, and when the ratio is too small pits are formed. A current and capacitance DLTS system using both voltage and optical excitation of a Schottky barrier diode has been set up to study defects at the InGaAs/InP interface. The system has been tested out, and we currently are trying to identify the traps that have been observed. This work will be continued to its completion. A comprehensive study of the hydride growth on InP has been made. The growth rate was measured as a function of the input HC1, input PH3, and downstream HC1 pressures, and the H2 flow rate. It was found that the growth rate initially increased with the input HC1 concentration and increased with the PH3 concentration as predicted by thermodynamics.