Dynamic Threshold MOS and Methods of Forming the Same

摘要

A chip includes a semiconductor substrate, a well region in the semiconductor substrate, and a Dynamic Threshold Metal-Oxide Semiconductor (DTMOS) transistor formed at a front side of the semiconductor substrate. The DTMOS transistor includes a gate electrode, and a source/drain region adjacent to the gate electrode. The source/drain region is disposed in the well region. A well pickup region is in the well region, and the well pickup region is at a back side of the semiconductor substrate. The well pickup region is electrically connected to the gate electrode.

主权项

1. A method comprising:
forming first isolation regions extending from a back surface of a semiconductor substrate into the semiconductor substrate; implanting the semiconductor substrate to form a well pickup region extending from the back surface of the semiconductor substrate to a well region in the semiconductor substrate; forming a transistor at a front surface of the semiconductor substrate, wherein the forming the transistor comprises:
forming a source/drain region extending into the semiconductor substrate, wherein a bottom surface of the source/drain region contacts a top surface of the first isolation regions; and forming second isolation regions extending from the front surface of the semiconductor substrate to the first isolation regions.