Resistive element formed in a semiconductor substrate

摘要

A resistive element which is formed in a semiconductor substrate comprises a first semiconductor region which is formed in the semiconductor substrate and in which an impurity is diffused at a first concentration; a second semiconductor region which is connected to the first semiconductor region at one end and in which an impurity is diffused at a second concentration higher than the first impurity concentration; a third semiconductor region which is connected to the first semiconductor region at the other end and in which an impurity is diffused at a third concentration higher than the first impurity concentration; and the second and third semiconductor regions respectively including a portion whose cross section has a smaller area than the area of a boundary defined by the second and third semiconductor region with the first semiconductor region.