The flicker noise characteristics of strained-Si nMOS-FETs are significantly dependent on the gate oxide formation. At high temperature (900 C) thermal oxidation, the Si interstitials at the Si/oxide interface were injected into the underneath Si-SiGe heterojunction, and enhanced the Ge outdiffusion into the Si/oxide interface. The Ge atoms at Si/oxide interface act as trap centers, and the strained-Si nMOSFET with thermal gate oxide yields a much larger flicker noise than the control Si device. The Ge outdiffusion is suppressed for the device with the low temperature (700 C) tetraethylorthosilicate gate oxide. The capacitance-voltage measurements of the strained-Si devices with thermal oxide also show that the Si/oxide interface trap density increases and the Si-SiGe heterojunction is smeared out due to the Ge outdiffusion.

The correlations between the threading dislocations and the low-frequency noise characteristics of the n-type strained-Si field-effect transistors are studied using the devices with different sizes. The device-area-dependent VG (power spectral density of the gate referred voltage noise) ratio of the strained-Si devices over the control Si devices obtained form geometric average can be understood by the modified carrier number fluctuation model with excess traps from the Poisson distributed threading dislocations. The equivalent trap number per threading dislocation extracted from the area-dependent VG ratios is 85 for the strained-Si devices, and which results in 4.2X degradation of the VG for the strained-Si device with the device area of 625 m 2 .

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A cost-effective isolation technique using laser treatment is proposed to suppress the undesired crosstalk between dual power amplifiers (PAs), which are essential to multiple-input multiple-output communications system. Laser treatment not only reduces the small-signal coupling between dual PAs but also enhances the linearity of the PA under dual-PA operation mode. The figure of merit for the small-signal coupling has an improvement of 4.55 dB at 2.45 GHz, and the output power at 3% ( 30 dB) error vector magnitude (EVM) has a linearity improvement of 6.1 dB under 0-dB interference.Index Terms-Coupling, crosstalk, isolation, laser treatment, multiple input multiple output (MIMO), power amplifiers (PAs).

The package strain improves the noise figure (NF) of the low-noise amplifier (LNA). The maximum noise reduction is ∼0.53 dB (13%) at the operating frequency of 2.4 GHz under the biaxial tensile strain of 0.037%. The NF reduction of the strained LNA is mainly due to the enhanced transconductance and cutoff frequency of the individual nMOSFET device under the same strain and bias conditions.