| 摘要 |
PURPOSE:To increase the hFE of a reverse directional transistor by providing a P type impurity region for blocking electron injection which contacts the lower surface with an N type buried region and the upper surface with the inactive base region of said transistor of an I<2>L element. CONSTITUTION:An N type diffused layer 42 is formed on a P type Si semiconductor substrate 41, and next P type diffused layers 43 and 44 are simultaneously formed immediately under an oxide film isolation region and in the layer 42. Then, an N type epitaxial layer 45 and oxide regions 46 and 47 are formed. A P type impurity introduced region serving as the base region 50 of the reverse directional N-P-N transistor is formed, and an oxide region 56, en emitter 57 an N type high concentration region, etc. are formed. Further, boron is implanted in order to form a low resistant base region. In this process, the boron passes through the region 56, and accordingly the P type impurity region 61 for blocking electron injection connecting the diffused layer 44 is formed. |
