Patent attributes
A bipolar transistor in which the occurrence of Kirk effect is suppressed when a high current is injected into the bipolar transistor and a method of fabricating the bipolar transistor are described. The bipolar transistor includes a first collector region of a first conductive type having high impurity concentration, a second collector region of a first conductive type which has high impurity concentration and is formed on the first collector region, a base region of a second conductive type being formed a predetermined portion of the second collector region, and an emitter region of a first conductive type being formed in the base region. The bipolar transistor further includes the third collector region, which has higher impurity concentration than the second collector region, at the bottom of the base region. Therefore, it is possible to prevent the base region from extending toward the second collector region due to the third collector region when a high current is injected into the bipolar transistor, thereby improving the capability of driving a current of the bipolar transistor and preventing the occurrence of Kirk effect even during the injection of a high current.
