| 摘要 |
PURPOSE:To control the groove width by a method having the steps of forming a V-shaped groove, effecting a difusion from the surface of the V-shaped groove to form a P type layer, forming a P-side electrode in the limited area around the V- shaped groove, and applying a reverse bias to a control electrode formed on an N type layer provided around the P type layer. CONSTITUTION:A V-shaped groove 7 is formed in the form of a fringe on the surface of an N type GaAs layer 6, and Zn is selectively diffused to form a P type layer 8a. The end of the groove penetrates the N type AlGaAs layer 5 and reaches the P type AlGaAs layer 4. Then, electrodes 9a and 10 are attached to the P type layer 8a and the N type GaAs substrate 1. Control electrodes 11a and 11b are formed on the N type GaAs layer 6 and around the electrode 9a. As the voltage is applied between the positive electrode 9a and the negative electrode 10, electric current is concentrated to the narrow fringe part where the P type 8a penetrates the N type layer 5, and a laser oscillation takes place in the narrowed part of the P type layer 3 beneath the fringe. By applying a reverse bias between the layer 8a and layers 5, 6 using the control electrodes 11a and 11b as the positive electrodes, it is possible to control the effective width W1 of the fringe by the width of the depletion layer, i.e. by the reverse bias voltage. which in turn permits the control of the threshold electric current. |
