| 摘要 |
PURPOSE:To prevent circuit element deterioration and contact metal fusion under excessive backward voltages by a method wherein an inside element is connected to an input pad with the intermediary of a diffused resistor of prescribed length and, in the vicinity of the connection of the input pad and diffused resistor, a part of the channel stopper is removed. CONSTITUTION:A part 7' of a channel stopper 71 in the vicinity of a contact hole 4 is removed, Electrically, the device is a complex P-N junction structure wherein a diffused resistor 3 is loaded with backward voltages BV'21 and BV''21. The BV'21 is the backward voltage between the diffused resistor 3 and an epitaxial layer 1 while the BV''21 is the backward voltage between the diffused resistor 3 and a channel stopper 72. Accordingly, an avalanche breakdown in the vicinity of an input pad 5 due to an excessive, abnormal backward voltage introduced through the input pad 5 involves but a small current. An abnormal voltage wave travelling through the diffused resistor 3 is late in rising and low in height on account of the distribution circuit characteristics of the diffused resistor 3. This shows that a low capability of withstanding backward voltages between the diffused resistor 3 and the channel stopper 72 does not result in an avalanche breakdown, and a breakdown, if any, does not damage the junction because such a breakdown involves but a small current. |
