The trench MOS structure also creates charge-coupling effects in the drift region. As depicted in this slide, the charge-coupling effect changes the shape of the electric field distribution from linear to nonlinear. The same reverse breakdown voltages can be obtained with silicon that has much lower resistivity, as indicated by the sharp gradient of TMBS electric-field curve. The TMBS structure successfully alters the electric field distribution to move the stronger electric field away from the Schottky metal-silicon interface to the bulk silicon. As indicated, the depth of the surface electric field of the TMBS device is much lower than the planar Schottky device. The reduced surface field suppresses the barrier-lowering effect, which significantly reduces the leakage current for a given Schottky barrier height. This allows lower Schottky barrier heights to be used without sacrificing reverse-leakage performance, therefore lowering the forward-bias voltage drop.