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Monomer of acryloyl tri(1,1,2,2-tetrahydroperfluoro-octyl) citrate (FOC) and β-acryloyloxy 1,1,2,2-tetrahydroperfluoro-octyl propionate (FOP) were successfully synthesized and copolymerized with n-butyl acrylate by continuous process emulsion copolymerization. Thermal properties of resulting fluorinated copolymers were characterized by TGA. The water and oil repellency of the polymers used as textile finishing agent on cotton fabrics were investigated, and the surface energies were calculated. The X-ray photoelectron spectrometer (XPS) measurement showed strong surface enrichment of fluorinated segments.

Poly-connected MOSFETs can reduce chip area due to replacing some metal layer routing. Compared with conventional MOS, resistance of connecting poly (P2) is an additional factor which impacts MOS electrical performance, besides LDD and source/drain parasitic resistance. Conventional parasitic resistance extraction method requires a series of different gate length test structures. A new extraction method of parasitic resistance is demonstrated here, that is to extract the parasitic resistance from forward biased current vs. voltage characteristics of drain/bulk junction diode based on a single MOS test structure. Using this method, P2 layer deposition loading effect is successfully detected and poly space effect (PSE) of poly-connected MOSFETs can be well modelled in SPICE model. This new extraction method can also be applicable for conventional MOSFETs.

Bis(1H, 1H, 2H, 2H-perfluoro-octyl)methylenesuccinate (FOM)/ethyl acrylate (EA)/methyl methacrylate (MMA) copolymer (FOME) latexes, FOM/butyl acrylate (BA)/MMA copolymer (FOMB) latexes, and FOM/octyl acrylate (OA)/MMA copolymer (FOMO) latexes were synthesized by continuous emulsion polymerization. Solution polymerization was also carried out to prepare FOMB. The influences of fluorine content and curing conditions on the surface properties of polymer films were discussed. The water and oil repellency of cotton fabrics treated with the FOM copolymers was better than that of conventional poly(fluoroalkyl acrylate)s containing the same fluorinated chain. The polymer films or the treated fabrics were characterized by Fourier transform infrared, scanning electron microscope, atomic force microscopy, thermogravimetric analysis, x-ray photoelectron spectrometry, and wide angle x-ray diffraction. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci, 2013

Device with shallow trench isolation (STI) has inverse narrow width effect (INWE), that is the threshold voltage of narrow width transistors is lower than that of large width transistors. The conventional methods of improving INWE focus on STI module optimization, such as active area corner rounding, step height and divot control. In this paper, a new approach by implant optimization is proposed to improve INWE. For low power PMOS device, phosphorus halo implant is often used for its lower diode leakage characteristics. This paper reports optimized dual halo implant approach with both arsenic and phosphorus implants to improve INWE. This approach gives larger Gm*Rout and lower digital product chip stand-by current without reliability degradation.

A physics-based new gated diode SPICE compact model is provided considering the following two effects: (1) the leakage current under reverse bias of gated diode caused by the gate/diffusion overlap tunneling current; (2) the substrate conductivity modulation associated with high injection of carriers due to mobility saturation during high current transmission line pulse (TLP). The new SPICE model matches the silicon data under both ESD TLP and normal DC forward/reverse bias very well. The model is scalable in terms of finger width and number.

Thick GaN layer deposited by hydride vapor phase epitaxy (HVPE) on a metalorganic chemical vapor deposition (MOCVD) GaN template with a thin low temperature (LT) AIN intermediate layer was investigated. High resolution X-ray resolution diffraction (HRXRD) shows that the crystalline quality of thick GaN layer was improved compared with the template. As confirmed by atomic force microscopy (AFM) observations, the surface morphology of AIN intermediate layer helps to improve the nucleation of GaN epilayer. Photoluminescence (PL) spectra measurement shows its high optical quality and low compressive stress, and micro Raman measurement confirms the latter result. Thus, the deposition of the LT-AIN interlayer has promoted the growth of an HVPE-GaN layer with an excellent crystalline quality.

Thick GaN films were deposited on sapphire substrate by hydride vapour phase epitaxy (HVPE) in two steps at 1050 °C. The substrate was first nitridated for different times between 1 and 10 minutes before deposition of a 12 pm thick layer. X-ray rocking curves show a minimum for 5 and 7 minutes of nitridation. The shift of the photoluminescence peak (PL) at room temperature from 3.328 to 3.405 eV is consistent with the evolution of the microstructure which is characterised by non-compact layers for the shortest times of nitridation. The nitridation of the sapphire surface results in the formation of a damaged layer with a thickness varying with the nitridation times. In this interfacial area, flat interfaces are present, but A1N nanocrystals may be observed as well as an amorphous zones containing Al, O and N.

The morphology of the top surface for HVPE GaN layers grown on a MOCVD GaN template with a thin LT-AlN interlayer was investigated. This surface is characterized by the formation of numerous hillocks associated with screw dislocations or nanopipes. Their size is large and may reach more than 1 mm. The rocking curves of the 002 and 102 reflections correspond to a relaxed layer. The HREM images of the as-deposited and annealed interlayers show a perfect atomic structure with a very abrupt AlN/HVPE GaN interface. Thus, the deposition of the LT-AlN layer has promoted the growth of an HVPE layer with an excellent crystalline quality.

The results of first-principles plane-wave pseudopotential calculations of the elastic constants for a total of 25 III-V binary phases of both zincblende and wurtzite poly-types are presented. In addition, the study shows that the relaxation of internal parameters is extremely important to the accuracy of the results. A larger anisotropy factor favors the wurtzite structure while the zincblende structure is preferred for lower anisotropy factors. The boron phases have quite different behavior in both their elastic and structural properties from the other III-V compounds.

Device mismatch is one of the key parameters for the design of high-precision circuits since parameter variations limit circuit performance. Basically, the device mismatch is modeled by the classic Pelgrom's model in which the mismatch has L∧(−0.5)*W∧(−0.5) dependency. This model indeed satisfied industry needs for a long time. However, in practice, this may not be true especially for advanced technology nodes with more complex process steps. In literature published in recent years, one model different from the Pelgrom's model was proposed considering the short channel effect on matching degradation, and another one studied the impact of halo implantation on mismatch performance. In this paper, the mismatch compact models are first reviewed. Then, a comprehensive yet simple SPICE model is presented to cover various process effects on mismatch performance. In our model, the length and width dependency are modified with different exponent so that the mismatch is proportional to L∧(−nL)*W∧(−nW), where nL and nW are parameters to be extracted from experimental data. Examples are provided to show the capability of the new compact model.

Aromatic monomers with different fluorine concentrations and structural distribution patterns were synthesized. A series of copolymers based on methyl methacrylate, acrylate, and perfluorooctylalkyl acrylate were prepared by emulsion polymerization and were subsequently used as functional coatings to prepare water- and oil-repellent cotton fabrics. The composition and structure of the outmost layer of the treated cotton surface were analyzed. A strong surface segregation of fluorinated segments was found for the treated samples, as shown by X-ray photoelectron spectroscopy analysis. The basis for an in-depth appreciation of the relationship between the molecular structure of the monomers and the properties of corresponding copolymer-treated materials was provided (especially with regarding to their hydrophobic and oleophobic properties). The wetting characteristics of the fluorinated copolymers were found to be dependent on the density (number of side chains per constitutional repeat unit) and regularity of the fluorinated side chains. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4410–4418, 2013

In this paper, technology computer aided design (TCAD) was applied to optimize the fabrication process to reduce the parasitic capacitance of PMOS transistor at the source/drian (S/D) junction (Cj) in developing the 65 nm low leakage (65 nmLL) technology. It was found that Cj can be effectively reduced by combining relative high-energy well implant and proper threshold voltage (Vt) implant method. Through measured data and TCAD simulation, this paper also demonstrates a ?doping compensation effect? by tuning Vt and Halo implants with proper species, energy, and dosage, to achieve the Cj reduction.

High-quality GaN films were deposited by hydride vapor phase epitaxy (HVPE) on metalorganic chemical vapor deposition GaN templates using an anodized aluminum oxide mask. High-resolution X-ray diffraction, scanning electron microscopy, and cathod-oluminescence were used to highlight the excellent crystalline quality of the films, and the optical properties at different positions of the as-grown layers. The optical properties of the GaN films improved with increased film thickness. The PL peak position indicates stress relaxation by the AAO mask.

GaN films were deposited by hydride vapor phase epitaxy with and without adopting growth interruption modulation (GIM). The surface morphologies of these samples were observed by atomic force microscopy. After chemical etching, the surface morphology of GaN film grown directly on sapphire changed greatly and turned out to be N-polarity, which could be changed into Ga-polarity when growing via interruption modulation. Photoluminescence spectra showed that optical property of Ga-polar film was better than that of N-polar film. High resolution X-ray diffraction revealed the high crystalline quality GaN film grown by using the GIM method. The polarity conversion was the result of surface reconstruction when adopting GIM method.