Two photon absorption coefficients and processing parameters for photoresists

The two photon absorption (TPA) process is currently used to write high resolution microstructures for a variety of applications. Key parameters required to predict the final structure formation for this process are experimentally determined and reported in this article for two commercially available resists, Ormocore and SU-8. The measured TPA coefficients measured at 800 nm for Ormocore and SU-8 are 27 ± 6 and 28 ± 6 cm TW⁻¹, respectively. For Ormocore and SU-8 the dose required to write 35 and 50 μm high structures, respectively, were 54 ± 8 and 3.5 ± 0.5 J cm⁻³, respectively, and the measured contrasts were 15 ± 2 μm per decade J⁻¹ cm³ and 55 ± 8 μm per decade J⁻¹ cm³, respectively.     

Physical insights on electron mobility in contemporary FinFETs

Calibration of a physics/process-based model for double-gate (DG) MOSFETs to contemporary nanoscale undoped n-channel DG FinFETs reveals that 1) significant densities of source/drain donor dopants readily diffuse to the ultrathin (fin) body/channel, even with relatively long fin extensions, degrading electron mobility at low/moderate levels of inversion-carrier density (N/sub inv/), 2) surface-roughness scattering of electrons is less severe at the {110} silicon-fin surfaces than anticipated, and 3) strong-inversion electron mobility is quite high (e.g., /spl cong/290 cm/sup 2//V/spl middot/s at N/sub inv/=10/sup 13/ cm/sup -2/), being about three times higher than that in contemporary bulk-Si MOSFETs.     

Real time estimation of task specific self-confidence level based on brain signals

Multimedia Tools and Applications - Self-confidence is one’s own belief of success with respect to a specific task. Cognitive tasks like decision making, problem solving etc. are influenced a...     

Manufacturing batch size and ordering policy for products with shelf lives

This paper determines an optimum production schedule and raw material ordering policy for a family of products that share a common piece of production facility, and the inventory operates under a shelf life constraint. The problem of manufacturing a family of products under shelf life is addressed here mainly under three major issues: adjusted production rate, adjusted cycle time, and simultaneous adjustment of production rate and cycle time. This research addressed the issues in two major parts: the first part comprises planning an optimum production schedule and material ordering policy for a family of products with a constant production cost for operating the machines. The second part of the research considers a generalized production cost of operation where the cost of operation may increase or decrease depending on the production system. Results are demonstrated to show the computational mechanics and incremental advantages over the other models. A sensitivity analysis is performed to study the effect of variability of some parameters that play important roles in the models. An empirical test has also been conducted to show the relative performance of the models.     

Landslide hazard assessment: summary review and new perspectives

This paper deals with several aspects of the assessment of hazard and risk of landsliding. In recent years the interest in this topic has increased greatly and there are many technical papers dealing with this subject in the literature. This article presents a summary review and a classification of the main approaches that have been developed world-wide. The first step is the subdivision between qualitative and quantitative methods. The first group is mainly based on the site-specific experience of experts with the susceptibility/hazard determined directly in the field or by combining different index maps. The approaches of the second group are formally more rigorous. It is possible to distinguish between statistical analyses (bivariate or multivariate) and deterministic methods that involve the analysis of specific sites or slopes based on geo-engineering models. Such analyses can be deterministic or probabilistic. Among the quantitative methods discussed is the Neural Networks approach which has only recently been applied to engineering geology problems. Finally several considerations concerning the concept of acceptable risk and risk management are presented. Received: 30 November 1998 · Accepted: 2 April 1999     

Synthesis and mechanical wear studies of ultra smooth nanostructured diamond (USND) coatings deposited by microwave plasma chemical vapor deposition with He/H2/CH4/N2 mixtures

Ultra smooth nanostructured diamond (USND) coatings were deposited by microwave plasma chemical vapor deposition (MPCVD) technique using He/H₂/CH₄/N₂ gas mixture. The RMS surface roughness as low as 4 nm (2 micron square area) and grain size of 5–6 nm diamond coatings were achieved on medical grade titanium alloy. Previously it was demonstrated that the C₂ species in the plasma is responsible for the production of nanocrystalline diamond coatings in the Ar/H₂/CH₄ gas mixture. In this work we have found that CN species is responsible for the production of USND coatings in He/H₂/CH₄/N₂ plasma. It was found that diamond coatings deposited with higher CN species concentration (normalized by Balmer H_α line) in the plasma produced smoother and highly nanostructured diamond coatings. The correlation between CN/H_α ratios with the coating roughness and grain size were also confirmed with different set of gas flows/ plasma parameters. It is suggested that the presence of CN species could be responsible for producing nanocrystallinity in the growth of USND coatings using He/H₂/CH₄/N₂ gas mixture. The RMS roughness of 4 nm and grain size of 5–6 nm were calculated from the deposited diamond coatings using the gas mixture which produced the highest CN/H_α species in the plasma. Wear tests were performed on the OrthoPOD®, a six station pin-on-disk apparatus with ultra-high molecular weight polyethylene (UHMWPE) pins articulating on USND disks and CoCrMo alloy disk. Wear of the UHMWPE was found to be lower for the polyethylene on USND than that of polyethylene on CoCrMo alloy.