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Silicate glass - Wikipedia, the free encyclopedia Silicate glasses have been commonly used in the field of semiconductor device fabrication as an insulator between active layers of the semiconductor device. There will typically be contact holes or vias etched into the glass layers using wet etching or dry etching, and the silicate glasses can then be reflowed by heating in order to make smoother tops to the contact holes or vias, which makes the metal connections into the contact holes or vias more durable. The silicate glasses are typically formed of phosphosilicate glass (PSG) or borophosphosilicate glass (BPSG). en.wikipedia.org /wiki/Silicate_glass   (210 words)

Measurement of Electrical Conductivity of Glass Melts   (Site not responding. Last check: 2007-10-26) For accurate measurements of the electrical resistivity of glass melts several details have to be considered: At the beginning of measurements, relatively low potential barriers occur for some conducting ions due to a broad potential barrier distribution based on polarization effects in the electric field ("ionic polarization"). The conducting ions in the glass melt are discharged at the electrode surfaces and insulating layers are formed ("electrode polarization"). The applied voltage during resistivity measurements of glass melts is not reported in several papers unfortunately, despite its influence on the resistivity at high voltages due to various ionization potentials of the conducting ions [10, 11]. glassproperties.com /resistivity/ElectrResistMeasurement.htm   (1851 words)

British Glass - Types of Glass Glass with even higher lead oxide contents (typically 65%) may be used as radiation shielding because of the well-known ability of lead to absorb gamma rays and other forms of harmful radiation. Borosilicate glass, the third major group, is made mainly of silica (70-80%) and boric oxide (7-13%) with smaller amounts of the alkalis (sodium and potassium oxides) and aluminium oxide. Sodium borosilicate glasses may be used for sealing to molybdenum and the iron-nickel-cobalt (Fernico) alloys are frequently employed as a substitute, the amount of sodium oxide permissible depending on the degree of electrical resistance required. www.britglass.org.uk /AboutGlass/TypesofGlass.html   (1653 words)

Corning Museum of Glass | Resource on Glass | Glass and the Space Orbiter Ninety-six percent silica glass is the designation given to a type of glass made by a proprietary up to 900° C makes this glass the choice for industrial items such as furnace sight glasses and for outer windows on space vehicles where the glass must withstand the heat of reentry into earth's atmosphere. Fused silica is the most expensive of all glasses and shows the maximum resistance to heat shock as well as the highest permissible operating temperature (900° C for extended periods, 1200° C for short periods). The difference between a glass that is intended to remain a glass and a glass-ceramic in the glassy state lies in the nucleating agent which is included in the glass-ceramic batch and the proper ingredients for forming crystals. www.cmog.org /index.asp?pageId=749   (695 words)

Glass Glass is widely used for windows, bottles, glasses for drinking, transfer piping and recepticles for highly corrosive liquids, optical glasses, windows for nuclear applications etc. etc. Treating the glass thermally or chemically such that the outer surfaces are compressively stressed at relatively high levels, the middle region between the surfaces being under tensile stress. Glass fibres are made very small diameter and have a low ratio of surface cracks which are the main cause of the brittle property of glass. www.roymech.co.uk /Useful_Tables/Matter/Glass.html   (1516 words)

Glass - An Overview   (Site not responding. Last check: 2007-10-26) Glass is not one material but a term describing a large group of generic types of material displaying the properties which lead to them being described as glasses. Glass is an amorphous (non-crystalline) solid usually formed by the solidification of a melt without crystallisation. Glasses are not stoichiometric compounds but are variable compounds of substances, which can form glasses in isolation, with those that can not, thus leading to the great variety of possible compositions available to the technologist. www.azom.com /details.asp?ArticleID=1021   (1371 words)

Composite restorations and cements Glass ionomer restorations, like silicates also leach fluoride into the tooth structure throughout the life of the restoration and thus tend to reduce the likelihood of recurrent decay around the margins. Glass Ionomers are excellent fillings on the front surfaces of front teeth, but should not be used to rebuild top edges of these teeth due to their inherent weakness. The glass particles are mixed with the acrylic and then when the dentist is ready to place the restoration in the tooth he or she mixes a catalyst into the paste and this causes the acrylic to harden around the glass particles. www.doctorspiller.com /dental_materials.htm   (7036 words)

Quantitative Analysis of Silicate glass in Ceramic Materials by the Rietveld Method In the traditional ceramic field it is well known as the amorphous fraction, and in particular the silicate glass content, influences the thermomechanical properties of the manufacts. This is one constant characteristic of this model; the silica glass model is very sensible to the diffraction spectra and especially the Carnegieite structure donÕt require a wide d-range for his determination if starting from an already tested model. The procedure can be applied virtually to any type of amorphous content; we have presented here the case of silicate glass but any amorphous phase can be used in the procedure after identifying or refining its "nanocrystalline structure" approximation as was done for the crystalline compounds in the past and presently [1]. www.ing.unitn.it /~luttero/Publications/EPDIC_V/silicate_glass.html   (2380 words)

Mayflower Glass Lead glass is commonly used for the funnel and neck of the TV tube, while glass containing barium is usually used for the screen. Some of these "Glass ceramics", formed typically from lithium aluminosilicate glass, are extremely resistant to thermal stock and have found several applications where this property is important, including cooker hobs, cooking ware, windows for gas or coal fires, mirror substrates for astronomical telescopes and missile nose cones. Here the available glasses may be grouped according to their thermal expansion which must be matched with the thermal expansions of the respective metals so that sealing is possible without excessive strain being induced by the expansion differences. www.mayflowerglass.co.uk /xcart/skin1/site/typesofglass.htm   (1602 words)

Glasses Glasses are no more disordered than are liquids; which is to say, glasses are semi-ordered (or semi-disordered for you pessimists). Glasses are usually formed by melting crystalline materials at very high temperatures and then cooling them "quickly" before the atoms get a chance to settle into a nice, well-ordered arrangement. Lead glass is commonly used for the funnel and neck of the TV tube, while glass containing barium is usually used for the screen." From British Glass. hypertextbook.com /physics/matter/glass   (1733 words)

Method for forming semiconductor structure using modulation doped silicate glasses - Patent 5770469 It is known that the melting point of a silicate glass may be decreased by increasing the concentration of dopants in it. The modulation doped silicate glass structure may be used, for example, as an insulating structure between a device layer and a subsequently deposited metallization layer. C., the lightly doped borophosphorous silicate glass that results essentially bypasses its liquid phase and condenses directly from its vapor phase to its solid phase by the time the material is deposited onto the surface of layer 202. www.freepatentsonline.com /5770469.html   (7282 words)

Thick film copper conductor inks - Patent 4880567 The zinc-magnesium-barium-aluminum-silicate glass frit of the conductive ink of this invention is similar to a glass frit employed in the dielectric ink of commonly assigned copending U.S. patent application Ser. A further advantage of the glass frits used in the copper conductor inks of the present invention is that their thermal coefficients of expansion are close to that of alumina. In all of the formulations the devitrifying glass frit comprised, on a weight basis: 21.81 percent zinc oxide; 19.25 percent magnesium oxide; 5.88 percent barium oxide; 9.38 percent of aluminum oxide; 39.68 percent silicon dioxide; 2.00 percent phosphorus pentoxide; and 2.00 percent zirconium silicate. www.freepatentsonline.com /4880567.html   (3529 words)

Pat Owens Glass   (Site not responding. Last check: 2007-10-26) The dimensions of the sheet glass are determined at this stage, as are the details of the mechanical fastenings and mode of hanging. Before the plate glass is painted, I drill the holes to be used later for the mounting hardware. The glass rods that will be used in making the figures in one session at the torch are selected and placed in a torch-side computer controlled annealing oven and slowly brought up to a temperature that will allow them to be brought to the torch flame without shattering. www.patowensglass.com /pages/process.html   (2296 words)

All-Pak's Glass Container Glossary   (Site not responding. Last check: 2007-10-26) Blanks – The mold parts used in all glass container machines for preliminary formation of glass in preparation for the most efficient completion of glass containers in the finish molds where bottles are blown. Lug Finish – A glass container finish identified by horizontal tapering protruding ridges of glass that permit the specially shaped edges of the closure to slide between the protruding lugs and fasten securely with a partial turn. Press and Blow Process – A method of glass container manufacturing of large diameter finish containers in which the parison is shaped by pressing the glass against a blank mold with a metal plunger. www.all-pak.com /glassgloss.asp?navid=40   (1279 words)

New glass allows spectral hole burning Also, because it is a transparent glass (and not a crystal) it should be easy to manufacture in the shape of, for example, a disk. The same Eu -doped glass can either be used for spectral hole burning, or not, depending, respectively, on whether the sol-gel or melt fabrication method is used. Initially they used Sm ions to dope silicate glasses, but found that the materials they produced, though high temperature, could be inefficient and were difficult to make. www.spie.org /web/oer/march/mar98/newglass.html   (751 words)

Schreiber's Research (VMI) Develop in situ electrochemical procedures in soda-lime-silica glass melts (as well as model aqueous systems and sodium silicate glass melts) to understand and control the melt's redox state. Understanding the redox chemistry of glass melts; that is, what redox ions and how much of each are present at any time during glass processing when all redox components are simultaneously present in the melt. The purpose of this research effort is to correlate the redox and coordination chemistry of multivalent or transition elements in these ionic glasses to that in silicate glasses. academics.vmi.edu /chemistry/hds_research.htm   (1026 words)

Lead glass - Wikipedia, the free encyclopedia Lead glass is potassium silicate glass which has been impregnated with lead oxide (from 12% to 28% by weight) in its fabrication. The lead is not intended to affect the glass's ability to transmit light; depending on what the end use is to be, the goal is either to allow the glass to transmit visible light but to block x-rays, or to increase the refractive index of the glass, and thus its lustre, or sparkle. Unfortunately, the amount of lead glass finding its way into landfills as a result of discarded electronic equipment may be more of a hazard than the radiation it is designed to block. en.wikipedia.org /wiki/Lead_glass   (355 words)

Silicate glass glazing for aviation The glazing is a three-layer or multilayer composition which consists of high-strength glass, conductive and adhesive films. The heating systems working in two modes eliminate outer glass icing or overheating due to the electroconductive films and reliable control system for the regulation of voltage being applied. Glass materials produced in Russia, modern electroconductive and adhesive materials are used for glazing. technologiya.ru /tech/glasse/t0101.html   (212 words)

Sodium Silicate - Search Results - MSN Encarta   (Site not responding. Last check: 2007-10-26) Sodium silicate is formed when sodium carbonate (Na) and silicon... Aluminium is the most abundant metallic constituent in the crust of the Earth; only the non-metals oxygen and silicon are more abundant. - silicate glass compound: a compound of sodium and silica, often in solution. uk.encarta.msn.com /Sodium_Silicate.html   (119 words)

Corning Museum of Glass | Resource on Glass | Types of Glass Soda-lime glass is the most common (90% of glass made), and least expensive form of glass. Borosilicate glass is any silicate glass having at least 5% of boric oxide in its composition. Ninety-six percent silica glass is a borosilicate glass, melted and formed by conventional means, then processed to remove almost all the non-silicate elements from the piece. www.cmog.org /index.asp?pageId=739   (361 words)

Fireproofing Wood Buildings Sodium silicate is caustic and will etch glass eventually, so it may be that you should not wear expensive prescription glasses when working with it. Sodium silicate is not toxic, although it is possible that breathing the spray could be conceivably harmful. If termites are a problem, by mixing some borate (borax) with the silicates, it should make the wood even more resistant to termites (isoptera), and borate itself tends to make wood fireproof. www.angelfire.com /nc/isoptera/index.html   (1739 words)

MFA - CAMEO - Material Description Sodium silicate is made by fusing silicon dioxide (from sand) and sodium oxide (from soda ash). Water glass was also used in the Ransome process of stone preservation. This procedure used alternating solutions of an alkaline silicate and calcium chloride to form insoluble calcium silicate in the pores of the stone. www.mfa.org /_CAMEO/FRONTEND/fullrecord.asp?name=sodium+silicate   (252 words)

Science/Glass Flow/glass science cite   (Site not responding. Last check: 2007-10-26) Glass coatings are deposited from the vapor or liquid solution, sometimes with chemical reactions. Thus sodium silicate glass can be made by evaporating an aqueous solution of sodium silicate (water glass) and baking the deposit to remove water. The product of this process is indistinguishable from sodium silicate glass of the same composition made by cooling from the liquid." (p. tafkac.org /science/glass.flow/glass_science_cite.html   (216 words)

Borophosphosilicate glass - Wikipedia, the free encyclopedia Borophosphosilicate glass, commonly known as BPSG, is a type of silicate glass that includes impurities of both boron and phosphorus. Silicate glasses such as PSG and borophosphosilicate glass are commonly used in semiconductor device fabrication for intermetal layers, i.e., insulating layers deposited between succeedingly higher metal or conducting layers. BPSG has been implicated in increasing a device's susceptibility to soft errors - the Boron-10 isotope is good at capturing thermal neutrons from cosmic radiation. en.wikipedia.org /wiki/Borophosphosilicate_glass   (186 words)

Tech Specs/Data Glass in building - Determination of luminous and solar characteristics of glazing (light transmission, direct solar transmission, total solar energy transmission and ultraviolet transmission; corresponding characteristics of glazing). Glass in building - Laminated glass and laminated safety glass - Definition and description of component parts. Glass in building - Laminated glass and laminated safety glass - Test methods for durability. www.vanceva.com /design/pages/techspecs/default.asp?lang=en   (667 words)

NA-35/NA-40: LCD Display - Alumino Silicate Glass from HOYA OPTICS: Leading supplier of advanced optical materials & ... It displays minimal surface cloudiness from contact with fluoric acid and is ideal for device substrates requiring high deposition temperature or fine patterning, such as poly-Si TFT and EL. A polished glass test piece is immersed in a well-mixed solution of 5% HF at 25L C for 1 hour. Powdered glass particle size 420-590µ at a weight equal to the specific gravity is placed in a platinum net basket and soaked in 80 ml pure water (pH6.5-7.5) contained in a fused silica flask. www.hoyaoptics.com /specialty_glass/flat_panel.htm   (531 words)

Electrical Conductivity Calculation of Glass Melts   (Site not responding. Last check: 2007-10-26) The relation between the chemical composition and the electrical conductivity / resistivity of silicate glass melts at temperatures of 1000 The 95% confidence interval of the model prediction for industrial glasses in mass production largely depends on the composition of interest and the composition uncertainty, which can be quantified through a electrical conductivity calculation program based on Microsoft Excel derived from this work (Download Excel Calculator, 0.5 MB). Mazurin, O. Prokhorenko: "Electrical conductivity of glass melts"; Chapter 9 in: "Properties of Glass-Forming Melts" ed. glassproperties.com /resistivity   (940 words)

(WO/1997/024755) SEMICONDUCTOR STRUCTURE USING MODULATION DOPED SILICATE GLASSES   (Site not responding. Last check: 2007-10-26) The modulation doped silicate glass structure is formed by depositing at least two alternating layers of heavily-doped silicate glass (206) and lightly-doped silicate glass (204) over the first layer. On réalise la structure de verre au silicate à dopage modulé par dépôt sur la première couche d'au moins deux couches alternées: du verre au silicate fortement dopé (206) et du verre au silicate légèrement dopé (204). Le verre au silicate fortement dopé ainsi que le verre au silicate légèrement dopé peuvent être dopés aussi bien par un premier dopant que par un second dopant, le premier dopant pouvant être constitué, par exemple, par le phosphore, et le second dopant, par exemple, par le bore. www.wipo.int /pctdb/en/wo.jsp?KEY=97/24755.970710   (345 words)

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