A novel technique for in-line monitoring of micro-contamination andprocess induced damage

The use of a simple, rapid and nondestructive technique for inline monitoring of electrically active impurities introduced during wafer fabrication is reported. This AC surface photovoltage-based technique can determine the substrate doping type, doping concentration, oxide charge, and energy distribution of interface traps on both bare and oxidized silicon wafers without the formation of gate electrodes and substrate contacts. The technique is shown to have good reproducibility and resolution for quantifying the electrically active impurities, on the order of 1×10¹⁰ q/cm². Detection of contaminants and static charges by this technique is shown to correlate well with the electrical performance of thin dielectrics. The use of this technique for inline monitoring of very low levels of plasma-induced damage in the SiO₂/Si system is also discussed as is the potential for this tool in reducing furnace downtimes and in prompt identification of the source of contamination     

Wiki Technology as A “Free” Collaborative Tool within an Organizational Setting

This article provides a brief tutorial of Wiki technology as a collaborative tool. A case example from a university administration context suggests that - like many other end-user technologies - training and support needs should be carefully considered before the potential value of using this “free” technology to support knowledge management efforts can be satisfactorily realized.     

Bandpass solar exoatmospheric irradiance and Rayleigh opticalthickness of sensors on board Indian Remote Sensing Satellites-1B, -1C,-1D, and P4

This paper reports the bandpass solar exoatmospheric irradiance and Rayleigh optical thickness for six categories of sensors, namely, the linear imaging self scanning sensor (LISS)-I, -II, -III, the wide field sensor (WiFS), the panchromatic (PAN), and the ocean color monitor (OCM) which have been flown on Indian Remote Sensing Satellites (IRS)-1B, -1C, -1D, and -P4 platforms, based on laboratory measurements of relative spectral response (RSR) of each band. These estimates have been compared with similar contemporary international sensors     

Synthesis of (R,S)-muscone from 10-undecenoic acid

Muscone (3-methylcyclopentadecanone) is a major macrocyclic ketone found in the solid secretion, commonly known as musk, from the pouch ofMoschus moschiferus. Herein, we report its synthesis from 10-undecenoic acid, which is the major product of castor oil pyrolysis. Methyl 14-oxotetradecanoate was prepared by radical addition of methyl 10-undecenoate to acrolein. The terminal oxo group was protected as an acetal, and the ester group was treated with the anion of dimethyl methylphosphonate (CH₃-(O)P(OMe)₂, DMMP) to give 2-(15-dimethoxyphosphynil-14-oxo-pentadecane)-1,3-dioxolane. The acetal protection was removed and the Emmons-Horner reaction was carried out in K₂CO₃-t-butanol to give 2-cyclopenta-decenone. The addition of MeMgI in the presence of Cu₂Cl₂ gave muscone. IICT Communication No. 2930.     

Design of a Multibus-compatible colour graphics subsystem

Colour graphics subsystems can be used in a variety of applications such as high-end business graphics, low-end scientific computations, and for realtime display of process control diagrams. The design of such a subsystem is shown. This subsystem can be added to any Multibus-compatible microcomputer system. The use of an NEC 7220 graphics display controller chip has simplified the design to a considerable extent. CGRAM (CORE graphics on Multibus), a comprehensive subset of the CORE graphics standard package, is supported on the subsystem.     

Synthesis of 18-octadecanolide,a major constituent of dufour’s gland secretion ofColletes bees

18-Octadecanolide, a major constituent of Dufour’s gland secretion ofColletes bees, was synthesized by polymerization followed by depolymerization of 18-hydroxyoctadecanoic acid which in turn was obtained by hydrogenation of kamlolenic acid (18-hydroxy, 9-cis, 11-trans, 13-trans-octadecatrienoic acid) isolated fromMallotus philippinensis seed oil. The structures of the intermediates as well as the final lactone were established by infrared, proton nuclear magnetic resonance and mass spectrometric methods.     

Scaling relations for the performance of passive systems

From the correlation curves of the monthly solar heating fraction (SHF) as a function of monthly solar load ratio (SLR) for six different passive systems, it is empirically demonstrated that the annual SHF is well correlated with January SHF; this correlation is essentially independent of the passive type but dependent on location (climate). It is then shown mathematically that this is equivalent to the following scaling relation: the monthly SHF as a function of the monthly SLR is the same for all passive systems up to a scale factor of SLR. This scale factor depends on the passive system and has important physical relevance. The approximate validity of this scaling law is discussed. The simplification of performance prediction resulting from such a scaling law, as well as from the correlation of annual versus January performances, is pointed out.     

Crystal structure of Taq DNA polymerase in complex with an inhibitory Fab: the Fab is directed against an intermediate in the helix-coil dynamics of the enzyme

We report the crystal structure of Thermus aquaticus DNA polymerase I in complex with an inhibitory Fab, TP7, directed against the native enzyme. Some of the residues present in a helical conformation in the native enzyme have adopted a gamma turn conformation in the complex. Taken together, structural information that describes alteration of helical structure and solution studies that demonstrate the ability of TP7 to inhibit 100% of the polymerase activity of the enzyme suggest that the change in conformation is probably caused by trapping of an intermediate in the helix-coil dynamics of this helix by the Fab. Antibodies directed against modified helices in proteins have long been anticipated. The present structure provides direct crystallographic evidence. The Fab binds within the DNA binding cleft of the polymerase domain, interacting with several residues that are used by the enzyme in binding the primer:template complex. This result unequivocally corroborates inferences drawn from binding experiments and modeling calculations that the inhibitory activity of this Fab is directly attributable to its interference with DNA binding by the polymerase domain of the enzyme. The combination of interactions made by the Fab residues in both the polymerase and the vestigial editing nuclease domain of the enzyme reveal the structural basis of its preference for binding to DNA polymerases of the Thermus species. The orientation of the structure-specific nuclease domain with respect to the polymerase domain is significantly different from that seen in other structures of this polymerase. This reorientation does not appear to be antibody-induced and implies remarkably high relative mobility between these two domains.     

Improved convergence performance of RSER algorithms with modified gradient filtering

A modified gradient filtering technique is applied to a class of recursive sequential regression (RSER) algorithms, in order to improve the convergence performance. The performance behaviour of the new class of algorithms is studied using both all-pole and pole-zero examples.