In_1-xGa_xAs-GaSb_1-yAs_y heterojunctions by molecular beam epitaxy

Smooth films of n-In1-xGaxAs and p-GaSb 1-yAsy were grown by molecular beam epitaxy. As a function of the compositions, x and y, the lattice constants vary linearly while the energy gaps show a downward bowing. Abrupt heterojunctions made of these alloys with close lattice matching exhibit a series of current-voltage characteristics which change from rectifying to Ohmic as x and y are reduced. The relative location of the band-edge energies of the two semiconductors at the interface is shown to account for the unusual characteristics observed experimentally.