| 摘要 |
PURPOSE:To control a threshold value by grasping an N type active layer with layer having a larger forbidden band zone than that of said active layer, forming three pieces of P layer separating one another, which attain to said active layer penetrating through N layer of one side, and biassing each pn junction selectively. CONSTITUTION:An N type Ga0.39Al0.61As17, an N type Ga0.63Al0.32As active layer 18, an N type Ga0.39Al0.61As19 and an N type GaAs20 are layered on an N type GaAs substrate 16. A P layer 27 to 29 is formed to attain to the active layer 18 by a Zn diffusion and a photoetching method and then ohm-electrodes 25 to 27 and 28 are attached thereto. When the reverse bias and the order baisses are performed between the electrodes 25 to 27 and 28 and between the electrode 26 and 28, a depletion layer is enlarged in the active layer in accordance with the increase of the reverse bias and shut the current effectively, and as the result threshold value current decreases. In accordance with this constitution, the horizontal breadth of the active layer is controlled electrically, and threshold value current is controlled, thereby being able to obtain a lower threshold value current. |
