in situ removal of native oxide from silicon wafers

in many integrated circuit fabrication steps, it is important to be able to ensure that there is no native oxide on a silicon surface before the next layer is deposited. for example, when tungsten is deposited by chemical vapor deposition (cvd) by silicon/hydrogen reduction of wf/sub 6/, attack of the silicon surface can be extensive (i.e..

evaluation of the transverse flexure test method for composite materials

a preliminary evaluation of the transverse flexure test method was conducted, using unsized au4 and as4, and epoxy-sized as4, carbon fiber/epon 828 epoxy matrix composite materials. the transverse flexure test yielded significantly higher values of the transverse tensile strength of these unidirectional composites than did the standard tr..

chemical and physical properties of laser-treated poly(ethyleneterephthalate)

the effects on chemical and physical properties due to microstructuring of poly(ethyleneterephthalate) (petp) fiber surfaces by uv-laser treatment are investigated. data are given about a slight color change at the irradiated sites of laser-treated fabrics in relation to the amount of debris deposited under ablating conditions. the debris..

multi-analyte microelectronic biosensors

the author describes the use of monolithic silicon technology for the fabrication of multianalyte miniature biosensors for clinical applications. electrochemically generated conducting polymers were used to entrap enzyme at the sensing microelectrode surfaces. this enzyme immobilisation procedure allows precise control of the spatial dist..

lrp equipment characterisation at low temperatures and application to polysilicon bipolar emitter processing

a plasma-stimulated lpcvd rapid thermal processor has been developed. this processor is capable of operation in the limited reaction processing (lrp) regime and offers sequential in situ processes such as silicon deposition, plasma oxidation and interface pre-cleaning. incident power with wavelength greater than 1.1 mu m is absorbed by fr..

chemical modification of silicone elastomers for optics

polysiloxanes with si-h groups were chemically modified using vinyl compounds with phenyl, naphthyl, anthryl, and n-perfluorooctyl side groups by platinum catalysis (hydrosilylation). the introduction of aromatic groups increased the refractive index of poly(dimethyl siloxane) (n=1.403) up to n=1.70 depending on the degree of substitution..

xps study of the carbon fiber matrix interface

x-ray photoelectron spectroscopy (xps) combined with gas phase chemical modification was applied to study the variation of the carbon structure and quantity of functional groups introduced by oxidation of a carbon fiber surface. the amount of functional groups effective for adhesion of the matrix at the interface was correlated to the fra..

formation and behavior of surface layers on electron emission glasses

the thermochemical reduction of thin surface layers on multicomponent lead-silicate glasses is fundamental to their use in electron multiplier and microchannel plate devices. these surface layers can exhibit a specific conductivity as high as 10/sup -2/ ( omega cm)/sup -1/ and secondary electron yields up to 3.5. however, due to the compl..

interaction of organosilanes with glass fibers

systematic reaction of a glass surface with monofunctional organosilanes can be achieved by multiple coat-cure treatments. a gradual decrease in the polarity of the glass surface, measured by its wetting properties, monitors this reaction. a saturated surface results after ten coat-cure treatments, yielding a surface whose hydrogen bond c..

acid-base properties of glass surfaces

the adhesion of polymers to inorganic oxides such as glass is very dependent on acid-base interactions between the acidic or basic surface sites of the glass, and the basic or acidic functional sites of the polymer. this paper reviews the principles of such interactions, methods of measuring the acidity or basicity of surface sites, and t..