| 摘要 |
PURPOSE:To improve the electrostatic discharge breakdown strength of a semiconductor integrated circuit device by forming a P type layer which contacts at the lower end with an N<+> type buried layer in the vicinity of an N<+> type resistance element, which an area larger than the contacting area directly under the contact of the resistance element and contacts at the upper end with metal wirings to the external connecting terminal of the resistance element. CONSTITUTION:A P type layer 11 which contacts with an N<+> type buried layer 4 is formed in addition to the conventional structure, is connected at the upper end to the contact of a P type resistor 3 connected directly to the external terminal with metal wirings 7, extends at the lower end on the buried layer, and has a width larger than the contacting area of the resistance layer 3. When the substrate 1 is positive and the contact 6 is negative, an electrostatic discharge path 13 is added, the sum of the series resistors is smaller than the path 10, and a wide area is extended at the part which feasibly causes the most probable discharge breakdown. Accordingly, the static electricity is mainly flowed to the path 13. Since the existence of the layer 11 does not relate to the relative accuracy of the resistance, the sectional area of the layer 11 is expanded to decrease the current density, the breakdown withstand strength of the path 13 is sufficiently increased, and the static electricity discharge breakdown strength between the substrate 1 and the contact 6 of the resistance element can be improved. |
