Patent attributes
This invention is about a window interface layer in a light-emitting diode which comprises an n-type GaAs substrate with an n-type ohmic electrode at the bottom side thereof; an n-type AlGaInP cladding layer formed atop the substrate; an undoped AlGaInP active layer formed atop the n-type cladding layer; a p-AlGaInP cladding layer formed atop the active layer; a p-type window layer made of GaP; a p-type ohmic electrode formed atop the p-type window layer; and a highly doped p-type interface layer made of GaxIn1-xP (0.6≦x≦0.9) and interposed between the p-type cladding layer and p-type window layer wherein the highly doped p-GaInP interface layer possesses a band gap which is higher than that of the active layer and, however, smaller than that of the p-type cladding layer, and wherein the lattice constant lies between GaAs and GaP. In this way, the p-GaInP interface layer is interposed between a p-GaP window layer and a p-AlGaInP cladding layer for enhancing the film quality and the luminous efficiency as well as improving the electric property.
