A charge storage trench structure is provided underneath a body region of a field effect transistor to store electrical charges in a region spaced from the p-n junctions between the body region and the source and drain regions of a field effect transistor. The charge storage trench structure can be embedded in a dielectric material layer, and a semiconductor fin can be formed by attaching a semiconductor material layer to the top surface of the charge storage trench structure and by patterning the semiconductor material layer. The field effect transistor is formed such that the charge storage trench structure contacts a bottom surface of the body region of the field effect transistor, while not contacting any of the source and drain regions. The electrical charges stored in the charge storage trench structure are physically spaced from the p-n junctions, and are less prone to leakage through the p-n junctions.