| 摘要 |
PURPOSE:To prevent thyristor effect through isolated region by providing an epitaxial layer on a semiconductor substrate through a semicondutor layer having a low specific resistance and by forming isolated lateral transistor and I<2>L on such layer. CONSTITUTION:A layer 1a having a low specific resistance is formed on the surface of P type substrate 1 having a high specific resistance by implanting impurity ion. Then after forming the N<+> type buried layer 2, an N type epitaxial layer is grown. Thereafter an isolated region 4 is formed by diffusing P type impurity from the surface and thereby a pair of island regions 3a, 3b are obtained. A linear co-existing circuit can be obtained by forming the lateral transistor Q1 and I<2>LQ2 in respective island regions. Since the P type layer 1a having a low specific resistance is provided, a current I0 given to the isolated region 4 from the side of transistor Q1 outflows to the layer 1a as a current I2 before it reaches the side of transistor Q2, thereby suppressing the generation of thyristor effect. |
