| 摘要 |
PURPOSE:To prevent concentration of electric field and improve intensity of resistance to latchup and electrostatic breakdown strength, by causing contacts which are formed on a square guard ring so as to prevent potential gradient to be formed roughly at corner parts of the square guard ring and to be formed densely at the center part of a straight-line part. CONSTITUTION:The feature of a MOSFET 7 is shown in its configuration where source and drain electrodes 1 and 2 are formed in parallel so that they face each other and a gate electrode 3 consisting of polycrystalline Si is located between them and there are channel region 4 at a lower layer part of the electrodes and a well region 5 around the electrodes and at its outermost parts it has a guard ring 6. Contacts 81, 82, 83,... 8n on the guard ring 6 are formed in such a manner that they are rough at corner parts and dense in the vicinity of the center part of a straight line part. |
