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Let M be a smooth manifold and A a Weil algebra. We discuss the differential forms in the Weil bundles MA,π,M, and we established a link between differential forms in MA and M as well as their cohomology. We also discuss the cohomology in.

We revisit the algebra of polynomial integrodifferential operators and we give a generalization of its relations. Generators of prime ideals of height 1, of the maximal ideal, and of the smallest ideal of In are discussed. A technique for obtaining a generating set for a given two-sided ideal of In is also discussed.

Let V be a valuation domain and let A=V+εV be a dual valuation domain. We propose a method for computing a strong Gröbner basis in R=A[x1,…,xn]; given polynomials f1,…,fs∈R, a method for computing a generating set for Syz(f1,…,fs)={(h1,…,hs)∈Rs∣h1f1+⋯+hsfs=0} is given; and, finally, given two ideals I=〈f1,…,fs〉 and J=〈g1,…,gr〉 of R, we propose an algorithm for computing a generating set for I∩J.

The bonding configuration, hydrogen evolution, and defect content of rapid thermally annealed (RTA) SiO[sub x] :H films of different compositions were studied. Infrared absorption measurements showed that all the hydrogen present in the films is lost at annealing temperatures below 600°C without any change in the oxygen to silicon ratio of the films. The activation energy of the hydrogen release is in the 0.21-0.41 eV range independently of film composition, suggesting that the process occurs via network bond reactions. For annealing temperatures higher than 700°C, a change in the Si-O-Si stretching wave number from the initial unannealed value to the 1070-1080 cm[sup -1] range was promoted, independently of the initial film composition. Electron spin resonance measurements showed that all the films contain two type of bulk paramagnetic defects: the E' center (•Si...O[sub 3]) and the silicon dangling bond center (•Si...Si[sub 3]). The RTA process promotes a general decrease of defect concentration for annealing temperatures below 400°C. At higher temperatures, E' center disappears, and the •Si...Si[sub 3] center increases its concentration up to the 10[sup 17]-10[sup 18] cm[sup -3] range. This suggests that the RTA at higher temperatures promotes the formation of a high-quality, almost defect-free, SiO[sub 2] matrix in which highly defective Si nanocrystals are also formed, where the • Si...Si[sub 3] centers are located. [ABSTRACT FROM AUTHOR]

Bulk properties of SiN[sub x]:H thin film dielectrics and interface characteristics of SiN[sub x]:H/Si devices are studied by a combination of electrical measurements (capacitance–voltage and current–voltage characteristics) and defect spectroscopy (electron spin resonance). The SiN[sub x]:H films were deposited by an electron cyclotron resonance plasma method and subjected to rapid thermal annealing postdeposition treatments at temperatures between 300 and 1050 °C for 30 s. It is found that the response of the dielectric to the thermal treatments is strongly affected by its nitrogen to silicon ratio (N/Si=x) being above or below the percolation threshold of the Si–Si bonds in the SiN[sub x]:H lattice, and by the amount and distribution of the hydrogen content. The density of Si dangling bond defects decreases at moderate annealing temperatures (below 600 °C) in one order of magnitude for the compositions above the percolation threshold (nitrogen rich, x=1.55, and near stoichiometric, x=1.43). For the nitrogen rich films, a good correlation exists between the Si dangling bond density and the interface trap density, obtained from the capacitance measurements. This suggests that the observed behavior is mainly determined by the removal of states from the band tails associated to Si–Si weak bonds, because of the thermal relaxation of the bonding strain. At higher annealing temperatures the deterioration of the electrical properties and the increase of the Si dangling bonds seem to be associated with a release of trapped hydrogen from microvoids of the structure. For the silicon rich samples rigidity percolates in the network resulting in a rigid and strained structure for which the degradation phenomena starts at lower temperatures than for the other two types of samples. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

This paper presents the evaluation of a removal method to cancel the thermal convection effect that is generated in vertically positioned metal plates loaded by thermal waves when a lock-in temporal speckle pattern interferometry technique is used to detect hidden flaws. Additionally, the resolution of this technique to detect two nearby flaws is also analyzed. [ABSTRACT FROM AUTHOR]