| 摘要 |
PROBLEM TO BE SOLVED: To attain high response characteristics by composing first and second semiconductor layers of specific compound semiconductors and composing an emission layer of a compound semiconductor having lattice constant different from that of the first semiconductor layer thereby imposing lattice strain to the emission layer. SOLUTION: A first clad layer 16 is a first semiconductor layer, an active layer 18 is an emission layer and a second clad layer 20 is a second semiconductor layer. The first clad layer 16 is composed of a single crystal compound semiconductor of n-Alx Ga1-x As (O<x<1) and the active layer 18 is composed of a single crystal compound semiconductor of un-GaAs1-y Py (0<y<0.5). Since the first clad layer 16 has lattice constant of about 5.657Å while the active layer 18 has lattice constant of about 5.633Å and the lattice constant of the active layer 18 is smaller than that of the first clad layer 16, crystal growth takes place while being applied with a tensile stress in the active layer 18 and lattice strain based on the lattice mismatch can be imposed. |
