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Abstr act. The power and design complexity of parallel processors make the intercore communication mechanism face new requirement and challenges. This paper presents the design of the message passing mechanism and a router for a polymorphic multimedia processor, which employs two mechanisms of data communication, the shared memory among neighbouring processor elements and the remote messaging with routers. Remote messaging includes remote data transmission and remote function call. The router, which is the main remote communication mechanism, has input buffers, and employs a version of the XY routing algorithm. It is able to do efficient multicasting with fault tolerance. It adopts a specialized arbitration scheme to simplify design complexity. This improved architecture reduces the delay of inter-core communication and cuts power consumption. It also improves the performance of the polymorphic multimedia processor.

Low-frequency noise behavior in the MOSFETs processed in 65 nm technology is investigated in this paper. Low-frequency noise for NMOS transistors agrees with McWhorter's theory (carrier number fluctuation), low-frequency noise in the sub-threshold regime agrees with McWhorter's theory for PMOS transistors while it agree with Hooge's theory (carrier mobility fluctuation) in the channel strong inversion regime. According to carrier number fluctuation model, the extracted trap densities near the interface between channel and gate oxide for NMOS and PMOS transistor are 3.94 × 1017 and 3.56 × 1018 cm−3/eV respectively. According to carrier mobility fluctuation model, the extracted average Hooge's parameters are 2.42 × 10−5 and 4 × 10−4. By consideration of BSIM compact model, it is shown that two noise parameters (NOIA and NOIB) can model the intrinsic channel noise. The extracted NOIA and NOIB are constants for PMOS and their values are equal to 3.94 × 1017 cm−3/eV and 9.31 × 10−4 V−1. But for NMOS, NOIA is also a constant while NOIB is inversely proportional to the effective gate voltage. The extracted NOIA and NOIB for NMOS are equal to 3.56 × 1018 cm−3/eV and 1.53 × 10−2 V−1. Good agreement between simulation and experimental results is achieved.

Density of localized states (DOS) over the band-gap determines the electrical and instability characteristics in the indium zinc oxide thin film transistor (IZO TFT). In order to propose an accurate extraction method for DOS in the bulk region, low frequency noise and multi-frequency capacitance voltage characteristics are measured and analyzed in this paper. Firstly, the relationship between surface potential and gate voltage is extracted based on subthreshold I-V characteristics. The extraction results show that the surface potential increases with the increase of gate voltage in the sub-threshold region. When the Fermi level is close to the bottom of conduction band, the increase of surface potential should be saturated. Secondly, drain current noise power spectral densities in the IZO TFTs under different operation modes are measured. Based on carrier number fluctuation mechanism, the flat-band voltage noise power spectral density is extracted and localized state near IZO/SiO2 interface is then calculated. By considering the emission and trapping processes of carriers between localized states, the distribution of bulk trap density in the band-gap is extracted based on low frequency noise measurement results. The experimental results show an exponential tail state distribution in the band-gap while NTA is about 3.421020 cm-3eV-1 and TTA is about 135 K. Subsequently, contact resistances are then extracted by combining capacitance-voltage characteristics with I-V characteristics in the linear region. The extrinsic parasitic resistances at gate, source, drain are separated. By considering charges trapped in the localized states and free carriers, the distributions of deep states and tail states in the active layer of IZO TFT are extracted through multi-frequency capacitance-voltage characteristics. The experimental results also show an exponential deep state and tail state distribution in the band-gap while NDA is about 5.41015 cm-3eV-1, TDA is about 711 K, NTA is about 1.991020 cm-3eV-1, and TTA is about 183 K. The above two proposed extraction methods are compared and analyzed. The deviation between two extraction results may relate to the existence of neutral trap in the gate dielectric which is also an important source of low frequency noise in the IZO TFT.

Polymer thin-film transistors (PTFTs) based on poly(3-hexylthiophene) are fabricated by the spin-coating process, and their photo-sensing characteristics are investigated under steady-state visible-light illumination. The photosensitivity of the device is strongly modulated by gate voltage under various illuminations. When the device is in the subthreshold operating mode, a significant increase in its drain current is observed with a maximum photosensitivity of 1.7×103 at an illumination intensity of 1200 lx, and even with a relatively high photosensitivity of 611 at a low illumination intensity of 100 lx. However, when the device is in the on-state operating mode, the photosensitivity is very low: only 1.88 at an illumination intensity of 1200 lx for a gate voltage of −20 V and a drain voltage of −20 V. The results indicate that the devices could be used as photo-detectors or sensors in the range of visible light. The modulation mechanism of the photosensitivity in the PTFT is discussed in detail.

In this paper, we prove that the Veronese surface can be determined by the 1-spectrum of the Laplace operator.

Polymer-based thin film transistors (PTFTs) with poly(3-hexylthiophene) (P3HT) as semiconducting active layers are successfully fabricated on silicon substrates in air which are used as gate electrods. HfTiO film deposited by RF sputtering method is used as gate insulators,and gold metal is used as source and drain electrodes. The HfTiO surface is modified by using octadecyltrichlorosilane solution in the fabrication process. Experimental results indicate that the PTFTs show good saturation behaviors at low drive voltages (-2 cm2/V ·s. The frequency-dependence and hysteresis effect are observed in the C-V measurements for the metal-polymer-oxide-silicon (MPOS) capacitors,and discussed in detail to understand their physical mechanism.

Polymer-based thin film transistors （PTFTs） were successfully fabricated on silicon substrates which was used as gate electrode, thermal silicon dioxide was used as gate insulators and poly（3-hexylthiophene） as semiconducting active layers for the transistors. The fabrication and measurement of the devices were all performed in the clean air. The PTFTs with a surface-modified gate insulator show better electric characteristics with the field-effect mobility of 0.02 cm2/（Vs） and the on/off ratio higher than 105.