| 摘要 |
PURPOSE:To obtain an LED having extremely high luminous power conversion efficiency by controlling the depth of diffusion so that a P type diffusion region is confined within an N type GaAlAs growth layer. CONSTITUTION:A P type diffusion region 7 by Zn, etc. is not formed so as to be directly contacted with a P type GaAlAs growth layer 2, and floated electrically while holding the thin N type GaAlAs region. That is, the P type diffuion region 7 is not made reach to the lower P type GaAlAs growth layer 2. Accordingly, even when forward currents are flowed through an LED, currents do not flow through the P-N junction of a side wall, luminous power conversion efficiency thereof is inferior substantially, because the P type diffusion region 7 is floated electrically. Since the N type GaAlAs region 3 under the P type diffusion region 7 is thin, lateral resistance is enlarged, and forward currents, which cross the P-N junction in the region and flow in the lateral direction, are reduced consisderably, thus approximately concentrating currentts only to the P-N junction under a light-emitting surface. It is preferable that the N type GaAlAs region under the P type diffusion region 7 is thin as much as possible, but the effect actually becomes more remarkable when the thickness is controlled to several mum or thinner from approximately 10mum. |
