| 摘要 |
PROBLEM TO BE SOLVED: To provide an epitaxial wafer for an LED of a structure having superior economy and utility which has a high luminous efficiency equal to what is heavily doped and film-thickened. SOLUTION: On a first upper clad layer 5 on an emission surface side, a second upper clad layer 6 whose band gap energy is more powerful than that of an active layer 4, and the surface (emission surface side) of the second upper clad layer 6 is planar-doped (7) or pulse-doped with dopant of the same conductive type as the second upper clad layer 6. Thereby current poured from an electrode of the emission surface side is diffused efficiently, and luminous efficiency is improved, without deteriorating crystal quality of the whole pn junction by film-thickening/heavily doping the whole second upper clad layer 6. |
