Lattice-Matched and mismatched multiquantum-well heterostructure photodiodes for operation at 1.1 to 1.5 μm

The first electron and hole sub-band energies of lattice-matched and strained-layer superlattices using the In_xGa_yAl_1-x-yAs and In_1-xGa_xAs alloys, respectively, have been calculated. The results indicate that devices operating at ˜ 1.1 to 1.5 μm can be fabricated with such periodic and biperiodic structures. Calculations using the miniband parameters and materials characteristics indicate that avalanche photodiodes with χ/β≅ 3-5 can be made with these multiple heterostructure layers.