Optical semiconductor device

Abstract

Abstract PURPOSE:To improve controllability, to lower operating voltage and to enhance efficiency by selecting the state, in which there are the quantized levels of electrons and holes, and the state, in which one is not quantized, by an electric field in the direction of laminating in a well layer having quantum well structure. CONSTITUTION:An N-type InAlAs clad layer 2, an absorption region 3 having quantum well structure consisting of InGaAs well layers 3a and GaSbAs barrier layers 3b, a P-type InAlAs clad layer 4 and a P-type InGaAs cap layer 5 are laminated and shaped onto an N-type InP substrate 1, and electrodes 6 and 7 are applied respectively onto the surface of the layer 5 and the rear of the substrate 1. According to such constitution, a barrier is formed only to either one of a conduction band or a valence band by the hetero-junction of the well layer 3a and the barrier layer 3b. That is, the layer 3b is formed to an N type when the barrier is shaped to the conduction band, the layer 3b is formed to a P type when the barrier is shaped to the valence band, and the impurity concentration of the layer 3b is made higher than the layer 3a in either case. Accordingly, electrons or holes are generated in the layer 3a by the confinement effect of the layer 3b.

Inventors

• 👤 Tatsuya Ohori

Bibliographic Details