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The DC characteristic and low-frequency (1= f ) noise behavior of strained-Si 1Àx Ge x p-type metal-oxide-semiconductor field-effect transistors (pMOSFETs) with 15 and 30% Ge channel have been investigated and compared with those of Si control counterparts. Enhancement in effective hole mobility of 24 and 45% were obtained in strained-SiGe devices with a 15 and 30% Ge channel, respectively. The strained-SiGe pMOSFETs with a higher Ge buried channel exhibit lower 1= f noise, indicating that more carriers are confined in the SiGe channel and interface scattering is remote. Moreover, we also found that the Ge concentration plays an important role in the noise mechanism. A new observation shows that carrier number fluctuation is more suitable for interpreting the mechanism of 1= f noise in strained-SiGe devices with 30% Ge channel, while both number fluctuation noise and mobility fluctuation noise are likely to contribute to the characteristics of SiGe pMOSFETs with 15% Ge and the Si control device.

In the fabrication of plastic components with micro or nano structures, injection molding is one of the simple and most cost-effective processes. In the injection molding process, a complete filling of the micro or nano structures is necessary to fabricate a successful product. However, it is difficult to fully fill nano structures with an aspect ratio close to one or higher by the conventional molding process. In this study, mold inserts with nano channels were constructed by a LIGA-like process. The effects of the processing parameters and infrared heating on the filling of the nano structures were explored experimentally. Increasing the mold temperature, pressure, or filling rate did not improve the filling distance in nano channels with the conventional molding process significantly. Thus, an infrared mold surface heating system was introduced to assist the molding of the nano structures. To enhance the heating efficiency and reduce the cycle time, a heat-resistant layer was inserted under the mold cavity. The heat resistant plate led the heating system to work more efficiently. It easily increased the surface temperature over the glass transition temperature of plastic, thus fully filling the nano structures.

The use of low-frequency (1/f) noise to evaluate low-cost stress-memorization technique (SMT) induced-stress in n-type metal–oxide–semiconductor field-effect transistors has been investigated. As compared to device without SMT process, the comparable 1/f noise level obtained for strained Si devices with the low-cost SMT process indicates that adding the low-cost SMT process will not affect the Si/SiO2 interface quality. Moreover, through observing experiment result and Hooge's parameter αH, the mechanism of 1/f noise in the both devices can be properly interpreted by the carrier number fluctuations correlated mobility fluctuations (unified model).