A NEW ASPECT OF MECHANICAL-STRESS EFFECTS IN SCALED MOS DEVICES

Deviation in device characteristics due to mechanical stress is investigated experimentally and analytically from the viewpoints of scaling and hot-carrier effects. In scaled MOS devices, the effect of uniaxial stress is reduced. However, the effect of vertical stress, such as mold stress, becomes a serious problem when the vertical stress causes compressive surface stress. Compressive stress has a serious effect on electron trapping in SiO2. These results provide important guidelines for the manufacture and package design of deep submicrometer devices.