Effect of Three Normal Mechanical Stresses on Electrical Characteristics of Short-Channel Metal–Oxide–Semiconductor Field Effect Transistor

The change in electrical characteristics due to mechanical stress is studied for short-channel metal–oxide–semiconductor field effect transistors (MOSFETs) fabricated on (001) substrate in advanced 65 nm technology. An experimental trial is carried out to investigate the effect of three independent components of mechanical stresses orthogonal to one another on drain current and threshold voltage using a pin-pressing apparatus and the cantilever method. The change in drain current agrees with the signs and magnitudes shown in the literature for surface stress on the (001) plane. On the other hand, the change versus stress vertical to the plane shows a peculiar phenomenon for pMOSFET. That is, the change decreases with the expected rate up to 90 MPa, but increases rapidly above 450 MPa. Although the physical mechanism is unclear at present, simultaneously generated biaxial horizontal strains possibly cause this peculiar phenomenon.