Determination of valence and conduction‐band discontinuities at the (Ga,In) P/GaAs heterojunction byC‐Vprofiling

摘要

The valence and conduction band discontinuities for the lattice matched (Ga,In)P/GaAs heterojunction have been determined by capacitance‐voltage (C‐V) profiling. Bothp‐pandn‐nheterojunctions were profiled, in order to obtain separate and independent values for both the valence‐band‐edge discontinuity (Dgr;Ev) and the conduction‐band discontinuity (Dgr;Ec). The band lineup is found to be of the straddling type with the valence‐ and conduction‐band discontinuities 0.24 and 0.22 eV, respectively, with an estimated accuracy of ±10 meV. Computer reconstruction of theC‐Vprofiles was used to check the consistency of the data. The band offset data indicate that the (Ga,In)P/(Al,Ga)As system should be staggered for a certain range of Al compositions.