| 摘要 |
PURPOSE:To increase the capacity variation ratio by a method wherein two each of ohmic electrodes and a control electrode forming a Schottky barrier are provided on an active layer while one of the ohmic electrodes and the control electrode are connected by a capacitor. CONSTITUTION:Ohmic electrodes 23, 25 and a control electrode 24 forming a Schottky barrier are provided on a one conductive type semiconductor 22 formed on a semiinsulating semiconductor substrate 21 while the electrode 24 and 25 are connected with each other by a capacitor 26. When the electrodes 24 and 23 are impressed with inverse bias voltage, the spread of depletion layer 27 below the electrode 24 is varied while the resistance of layer 22 is varied corresponding to the variation of depletion layer capacity. Making the display of the equivalent circuit of this variable capacity diode, the electrodes 23 and 25 are connected with each other by a resitor 29 in the no-depletion region of layer 22. Besides, the resistance of resistor 29 is varied corresponding to the inverse voltage between the electrodes 23 and 24 from the minimum to the maximum value. Through these procedures, the capacity variation may be maximized. |
