| 摘要 |
PURPOSE:To form an electrostatic surge protective circuit on a GaAs substrate by shaping two Schottky diodes between an input terminal and an FET connecting terminal through a resistor on the same substrate in a GaAs FET formed on the substrate. CONSTITUTION:An N type impurity layer 2 is formed on a semi-insulating GaAs substrate 1. Metallic films 5, 5' are in ohmic-contact with the impurity layer 2, and connect to a GaAs semiconductor element through an input terminal 3 and a terminal 4. Metallic layers 6, 6' shaping Schottky junctions together with the impurity layer 2 are formed, and grounded through resistors 9, 9'. When high-voltage electrostatic charges are applied to the terminal 3 in an equivalent circuit shown in the diagram, a Schottky junction 7 junction-breaks down, and discharge passing through the resistor 9 breaks down a Schottky junction 7', and the potential of the terminal 4 is clamped. Accordingly, the breakdown of an element is prevented. |
