| 摘要 |
PURPOSE:To enable to attenuate a junction leak current by a method wherein, in the semiconductor device in which a buried type element isolation technique is used, one end of a groove has a vertical surface against the main surface of a substrate and the other end of the groove has an obtuse angle, and an inversion preventing layer is provided on a slanted surface. CONSTITUTION:An anisotropic etching is performed on the main surface of a substrate, and a groove 27 to be used for isolation of a well of 4.5mum in depth is formed. At this time, the side wall on the element region side of a P-channel makes a vertical surface to the main surface of the substrate, and on the other hand, the other side wall makes an obtuse angle to the main surface of the substrate. Then, a CVD oxide film 30 is buried in the groove 27, and a P<-> type field inversion preventing layer 31 is formed by activating a boron-ion-implanted layer 29. As the P<-> type inversion preventing layer 31 is formed on the inclined surface of one of the side faces of the substrate 21 which are opposing each other through the intermediary of the CVD oxide film 30 which is an element isolation material, the junction leak current between the two side walls can be attenuated, thereby enabling to improve element characteristics. |
