A study of deep levels by transient spectroscopy on p-type liquid-phase-epitaxial GaxIn1−xAsyP1−y grown on semi-insulating InP

Abstract

p‐type layers of InP, Ga_0.28In_0.72As_0.6P_0.4 (λ=1.3 μm) and Ga_0.47In_0.53As (λ=1.65 μm) grown by liquid ‐phase epitaxy on semi‐insulating InP:Fe substrates have been investigated by deep level transient spectroscopy. In InP, we have found near the surface a majority‐carrier trap which is located at 0.22 eV above the top of the valence band. A very similar trap (capture cross section and energy) appears with about the same concentration in the quaternary layer but is not present in the ternary layer. Thus, we suggest that this trap could be related to the phosphorus sublattice (e.g., a complex, a vacancy, or a substitutional impurity), caused by a phosphorus depletion produced at the end of the epilayer growth. Other traps have been found in quaternary and ternary layers but are not identified.