| 摘要 |
<p>PURPOSE:To enable setting of the min. quantum level formed in well layers to a desired value by adopting the constitution in which, of the barrier layers and well layers constituting the superlattice, only the well layers or the barrier layers or the well layers and the barrier layers are lattice-mismatched with a substrate within the range where lattice defects are not generated. CONSTITUTION:The constitution in which, of the barrier layers A and well layers B constituting the superlattice, only the well layers B or only the barrier layers A or the well layers B and the barrier layers A are lattice-mismatched with the substrate within the range where the lattice defects are not generated is adopted. Namely, the lattice defects are not generated if the respective layer thicknesses of the superlattice are several 100Angstrom or below even if about 1% difference in the lattice constant from the substrate (lattice mismatch) exists in the superlattice structure. A desired forbidden band width Eg is obtd. by changing the compsn. of the well layers and the barrier layers in the ternary system of the well layers if the lattice mismatch is within about 1%, by which the desired min. quantum level is set.</p> |
