| 摘要 |
PURPOSE:To shorten the propagation delay time, and to improve a current amplification factor by diffusing an impurity up to the surface of an epitaxial layer and forming a base in a vertical type transistor when a second buried layer is shaped into a first buried layer in the surface of a substrate and a collar section is formed to the epitaxial layer. CONSTITUTION:An N-type impurity is diffused to the surface of a P-type semiconductor substrate 1 to form first buried layers 2A, 2B, the ions of a P-type impurity are implanted to shape second buried layers 12 and 13, and an N-type epitaxial layer 3 is formed onto the whole surface. Phosphorus is introduced as an impurity, and a collar section 4 is shaped through heat treatment. The impurity in the buried layers 12, 13 is diffused up to the surface of the layer 3 by the operation, thus forming a base 12A and isolation regions 13A in a vertical type transistor. A base 6 in an N-P-N transistor 20, an injector 11, a base contact 14 and a cap region 15 in a lateral type P-N-P transistor, an emitter 7 and a collector 8 in the N-P-N transistor 20 and a collector 10 in a vertical type N-P-N transistor are shaped. |
