Investigation of Low Frequency Noise in Uniaxial Strained PMOSFETs

Abstract

We have investigated the low frequency noise characteristics for uniaxial strained PMOSFETs. In the low vertical bar V(gst)vertical bar regime, the 1/f noise is dominated by the carrier-number-fluctuations and the S(Id)/I(d)(2) is increased by the enhanced g(m)/I(d) for the strained device. Nevertheless, the S(Id)/I(d)(2) of the strained device is almost the same as the unstrained one at a given g(m)/I(d). Furthermore, with the application of uniaxial compressive strain, the attenuation length lambda is reduced because of the increased out-on-plane effective mass and tunneling barrier height. The reduced lambda may result in a smaller S(Vg). In the high vertical bar V(gst)vertical bar regime, the 1/f noise is dominated by the mobility-fluctuations and the S(Id)/I(d)(2) is increased due to the larger Hooge parameter for the strained device.