SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD THEREOF

摘要

There are included: forming element isolation regions in a semiconductor substrate; introducing a first impurity of a first conductivity type, to thereby form a first well and a second well of the first conductivity type; introducing a second impurity of a second conductivity type, to thereby form a third well of the second conductivity type and introducing the second impurity into a region between the first well and the second well, to thereby form a separation well of the second conductivity type; and further introducing a third impurity of the second conductivity type into the region between the first well and the second well.

主权项

1. A semiconductor device comprising:
element isolation regions that are formed in a semiconductor substrate and demarcate element regions; a first well of a first conductivity type formed in the semiconductor substrate; a second well of the first conductivity type formed in the semiconductor substrate; a third well of a second conductivity type, which is a conductivity type opposite to the first conductivity type, formed in the semiconductor substrate; a fourth well of the second conductivity type formed in the semiconductor substrate; and a first separation well of the second conductivity type formed under the element isolation region in a region between the first well and the second well, wherein the concentration of an impurity of the second conductivity type in the first separation well at a first depth deeper than a bottom surface of the element isolation region and shallower than a bottom surface of the first well is equal to the sum of the concentration of an impurity of the second conductivity type in the third well at the first depth and the concentration of an impurity of the second conductivity type in the fourth well at the first well.