Showing papers on "Silicon oxide published in 1981"

Mos type semiconductor device

Abstract: PURPOSE:To eliminate the insulating breakdown of an insulating oxidized film layer due to high frequency surge by increasing the thickness of the film layer of an input unit larger than the other part in response to the peak value of the surge. CONSTITUTION:An Si3N4 11 is grown on the overall surface of a P type silicon wafer 1, an Si3N4 of a region 10 is removed, a window is opened (a), and a silicon oxidize layer 2a is formed on the opened region 10 (b). Then, a silicon oxide layer 2b and further a silicon oxide layer 2c are formed based on similar LOCOS method (a silicon local oxidizing method) (c) and (d). Thereafter, polycrystalline silicons 5, 5a are formed on silicon oxide layers 2a, 2c (e), and then or simultaneously a gate 8 is formed by diffusion (f). Metal wirings 3, 5 are eventually formed by the deposition of aluminum (g).

Oxygen impurity effects at metal/silicide interfaces: Formation of silicon oxide and suboxides in the Ni/Si system

Abstract: The effect of oxygen impurities on the Ni/Ni2Si interface has been investigated via ion implantation using x-ray photoelectron spectroscopy (XPS), 4He + backscattering, and 16O(d,alpha)14N nuclear reactions. Oxygen dosages corresponding to peak concentrations of 1, 2, and 3 atomic percent were implanted into Ni films evaporated on Si (100) substrates. The oxygen, nickel, and silicon core lines were monitored as a function of time during in situ growth of the Ni silicide to determine the chemical nature of the diffusion barrier known to form in the presence of oxygen impurities. It is shown that neither Ni oxide or mixed compounds such as Ni2SiO4 are involved in the barrier formation. The data demonstrate that as the advancing Ni/Ni2Si interface encounters oxygen in the Ni film, silicon suboxides (Si2O3, Si2O, and SiO) are formed. As more oxygen is encountered, Si takes on a full coordination of oxygen, forming SiO2. When a sufficient layer of SiO2 has formed, Ni metal is no longer able to diffuse through to the Si/Ni2Si interface to continue the solid phase reaction. It has been determined under UHV annealing conditions that the amount of oxygen necessary to stop the Ni diffusion is 2.2×10^16 O/cm^2. These experiments also provide a novel approach for synthesizing Si oxides and suboxides in a metallic matrix for examining relaxation effects in XPS as well as providing model compounds for Si/SiO2 interfacial studies.

Insulation process for integrated circuits

Abstract: Capacitors or dual layer metalization interconnects are formed in an integrated circuit utilizing two layers of polycrystalline silicon (22, 24) separated by a thin insulation region (23). The insulation region formed between the two polycrystalline silicon regions has substantially fewer defects than the insulation regions used in prior art techniques due to the use of a unique process wherein the polycrystalline silicon layer (24) overlying the insulation layer (23) protects the insulation layer from attack during subsequent processing. An improved dielectric strength is provided by forming the insulation region (23) utilizing composite layers of silicon oxide (23a, 23c) and silicon nitride (23b).

Process of preparing silicon tetrafluoride by using hydrogen fluoride gas

Abstract: A process of preparing silicon tetrafluoride by introducing hydrogen fluoride gas into a dispersion of powdery silicon oxide material, which needs not to be pure SiO2, in sulfuric acid not lower than 65% in the concentration of H2 SO4. The reaction takes place even at room temperature. By using amorphous silicon oxide material, the rate of reaction can be enhanced with better yield. Preferably, the concentration of H2 SO4 in the liquid phase of the reaction system is maintained above 80% to obtain SiF4 containing little (SiF3)2 O.

Thin film piezoelectric oscillator

Abstract: PURPOSE:To facilitate impedance matching with an external circuit by forming two partial electrodes opposing to a floating partial electrode through a piezoelectric thin film in between, and then leading electric terminals out of those partial electrodes. CONSTITUTION:On a subtrate 21 of silicone, crystal, etc., having a hole 22 by etching, a thin film 23 of a semiconductor such as silicon oxide, silicon nitride, and silicon doped with boron or an insulator is formed, and then a piezoelectric thin film 24 of zinc oxide, aluminum nitride, etc., is formed thereupon. On the thin film 23, a floating electrode 25 is formed and the partial electrodes 26 and 27 are provided on the piezoelectric thin film 23 opposing to the floating electrode 25. Then when electric terminals are led out of the partial electrodes 26 and 27 and energized electrically, oscillation is performed in such a way that when the overlap between the electrodes 26 and 25 extends in the thickness direction, the overlap between the electrodes 27 and 25 contracts in the thickness direction.

Coating process using alkoxy substituted silicon-bearing reactant

Abstract: An improved process for chemical vapor deposition of coatings of the type bearing silicon oxide or silicon oxide/tin oxide mixtures. The process involves the use of mono- or di-alkoxy terminated permethylpolysilanes, preferably monomethoxypentamethyldisilane, as a silicon-donating reactant. Also disclosed are novel transparent silicon-bearing coating compositions which can be formed by the improved process to have any desired refractive index value from about 1.44 to about 2.0.

Process for tapering openings in ternary glass coatings

Abstract: A process for defining improved tapered openings in glass coatings requires that passivating layers be formed of a doped silicon oxide having a relatively low flow temperature formed on a layer of undoped silicon oxide. After the contact openings are formed, both oxide layers are heated to a temperature below the flow temperature of the doped layer for a period of time sufficient to only soften and partially reflow the doped layer, the temperature being insufficient to form a significant oxide growth on the exposed portion of the semiconductor body.

Plasma etching method

Abstract: PURPOSE:To adequately remove the defect layer of the etched surface by plasma- etching the film of the surface of a semiconductor substrate then subjecting the same repeatedly to oxidation, oxide removal and heavy metal removal treatments. CONSTITUTION:A silicon oxide film, a silicon nitride film for selective oxidation and a resist mask are formed on a silicon substrate or the like, and the silicon nitride film and silicon oxide film are etched by using a CF4+H2 gas etc. This etched surface is subjected to oxidation treatment by using sulfuric acid + hydrogen peroxide solution or the like, thence the thus formed oxide film is removed by using a dilute hydrofluoric acid or the like. In succession to this, the remained heavy metals are removed by using aqua regia. This operation is repeated several times. The induction of huge crystal defects called ''stacking fault'' in the semiconductor production process is decreased by this treatment.

Polycide electrodes for integrated circuits

Abstract: A semiconductor integrated circuit has electrodes, contacts and interconnects composed of a multilayer structure including a layer of polycrystalline silicon with an overlying layer of a refractory metal silicide such as MoSi 2 or WSi 2 . Adhesion of the metal silicide to the polysilicon is enhanced by forming a thin silicon oxide coating on the polysilicon before sputtering the metal silicide. The resulting structure has low resistance but retains the advantages of polysilicon on silicon.

Manufacture of semiconductor device

Abstract: PURPOSE:To prevent the partial etching of a gate metal, and to reduce the generation of leakage currents between a gate-source and a gate-drain by breaking the gate metal at a stepped section by using an eave section generated between first and second insulating films, thinly growing a third insulating film and forming a photo-resist pattern on the third insulating film CONSTITUTION:A third insulating film 8 is grown on the whole surface of a substrate, in which a gate metal is broken at a stepped section by using an eave section generated between a silicon oxide film and a silicon nitride film through a normal method, in several hundred Angstrom A silicon oxide film, a silicon nitride film, etc are used as the insulating film, and thickness is brought to approximately 300-600Angstrom The surface of the substrate is coated with a photo-resist 6, a photo-resist pattern is formed so as to completely coat a gate opening section, and unnecessary regions of the third insulating film 8, the gate metal 5, the second insulating film 3 and the first insulating film 2 are removed through etching in succession while using the pattern as a mask The photo-resist 6 on the substrate is removed, and an insulating film 7 for protecting the surface is grown newly, thus completing a device

Manufacture of semiconductor integrated circuit

Abstract: PURPOSE:To enable to perform a high density integration by a method wherein a polycrystalline semiconductor film and an insulating film are superposed in a self- matching manner. CONSTITUTION:After the double-layer film, consisting of a single crystal or polycrystalline silicon film 22 and a silicon nitride film 23, has been formed on the upper surface of a silicon semiconductor substrate 21, the double-layer film is selectively removed and a channel region 24 is formed. Then, a silicon oxide film 25 is formed and after the silicon nitride film 23 has been removed, a silicon oxide film 26 is formed and then an aperture section 27 is provided. A silicon oxide film 28 is formed and then a source and drain diffusing regions 29 and 30 are formed. Then, aperture sections 31 and 32 are provided on the silicon oxide film 26 and the electrodes 34 and 35, to be used for a gate electrode 33 and a source and drain, are formed.

Method for preparing an abrasive lapping disc

Abstract: A method for preparing a plastic lapping disc overcoated with an abrasive silicon oxide layer. The method comprises the steps of introducing the silicon oxide precursors into an evacuated chamber containing the plastic lapping disc wherein a first major surface of the plastic disc is substantially covered during the glow deposition. The precursors are then subjected to a glow discharge. An abrasive silicon oxide layer is deposited on a second major surface of the disc opposite the first major surface.

Surfaces of Vacuum-Deposited Silicon Oxide Films Studied by Auger Electron Spectroscopy

Abstract: Silicon oxide films were deposited at a rate of 10–20 A/min by heating commercial SiO powder in vacuums of 10-5 and 10-7 Torr and were analyzed by Auger electron spectroscopy (AES). To assign the Auger spectra with the energy range 50–100 eV from the film surfaces, AES was carried out on air-fractured and electron-irradiated surfaces of quartz. The spectra are attributed to a three-dimensional network of Si(–O–)4 tetrahedra; no spectra due to networks of Si(–Si–)4 tetrahedra were observed. These results were supported by low-energy electron energy-loss spectra observations. The Auger spectrum associated with oxygen vacancies was also observed, the intensity of this being higher for the films prepared in the higher vacuum. Thus the silicon oxide film surfaces are presumed to consist of a three-dimensional network of Si(–O–)4 tetrahedra with some oxygen vacancies.

Preparation of composite material by thermite reaction

Abstract: PURPOSE:To obtain the composite material with low porosity and a uniform layer thickness, in forming a ceramic layer by the thermite reaction and the action of a centrifugal force to an inner side of a metal hollow body, by adding a silicon compound or a metal compound as the third component to thermite reaction components CONSTITUTION:A mixture prepared by mixing an aluminum powder (78g), Fe3O4 (250g), silicon oxide (15g) and the like is deposited under pressure to an inner wall of a carbon steel pipe in an equal thickness Subsequently, said carbon steel pipe is rotated and ignited while a centrifugal force of 50G or more is applied and, after the operation is carried out for about 10min, the production is completed Further, in place of a silicon oxide, a silicon compound such as silicon nitride or the like or a metal compound such as aluminum oxide, tungsten oxide or the like is used in a ratio of 50wt% or less

Dry Processing for Fabrication of VLSI Devices

Abstract: Publisher Summary The process of changing a flat silicon wafer into a functioning electron device makes use of several different structure-forming techniques. The more commonly recognized are: chemical conversion of silicon into silicon oxide; film deposition by evaporation, sputtering, chemical vapor deposition (CVD), plasma-activated CVD, and mechanical processes such as spinning and spraying; diffusion; ion implantation; pulsed annealing; and selective removal of material by etching or lift-off. Except for mechanical deposition, which frequently involves the use of solvents, and selective removal processes, for which liquids are also required, most of the processes may be classified as dry. The use of dry etch techniques has already become commonplace at some stages in the manufacture of state of the art integrated circuits and it is generally believed that the successful approach to the manufacture of micrometer and submicrometer devices will have to make extensive use of dry etching.

Method of producing semiconductor device

Abstract: Disclosed is a method of producing a semiconductor device, comprising forming an oxidation-resistive insulating film having one or more openings on a semiconductor substrate, forming an impurity-doped polysilicon pattern in at least the opening of the insulating film by using a mask substantially equal in size to the opening, forming a silicon oxide film on the exposed surface of the polysilicon pattern by thermal oxidation, removing the insulating film, and depositing a conductive material and, then, patterning said conductive material layer for forming an interconnection electrode layer insulated from the polysilicon pattern by the silicon oxide film.

Manufacture of micro-cantilever onto silicon wafer

Abstract: PURPOSE:To form the micro-cantilever, which has a metallic specular surface conducting switching operation and is made of silicon oxide, by using a silicon oxide layer in place of a conventional P layer and employing a polycrystal silicon layer shaped through a CVD method, etc. in place of a silicon layer. CONSTITUTION:A silicon wafer 11 mirror-ground is oxidized, and the silicon oxide layer 12 with approximately 1mum thickness is formed onto the wafer. The polycrystal silicon layer 13 is shaped onto the surface of the layer 12 by approximately 20mum thickness through the CVD method, etc., the surface is mirror-ground, and the polycrystal silicon layer 13 is changed into the polycrystal silicon layer with approximately 10mum thickness. A silicon oxide layer 14 with approximately 1mum thickness and a metallic thin-film 15 are shaped onto the surface of the polycrystal silicon layer 13 in succession. The silicon oxide layer 14 is romoved in concave form, and opening sections 16 are moded. The polycrystal silicon layer 13 is chemically etched. The silicon oxide layer 14 of a section surrounded by the opening sections 16 is used as the micro-cantilever 17.

Ink jet nozzle plate

Abstract: PURPOSE:To obtain a nozzle plate of high mechanical strength having a high-precision nozzle by forming a groove which becomes a nozzle on one side of a silicon monocrystal substrate and overlapping another silicon substrate on the side where the said groove is formed to be joined together. CONSTITUTION:An SiO2 film 24 is formed on the upper surface of a silicon monocrystal substrate 21 whose face bearing A is (100). Then this silicon oxide film 24 is selectively etched and removed to form an opening 25. If the silicon substrate 21 is anisotropically etched through the opening 25, an etched face 26 having theta inclined at approximately 55 deg. with the surface of the silicon substrate 21 and a face bearing B at (111), is formed. The etching automatically comes to the end, forming a V- shaped groove 22 without any overetching. Later, the silicon oxide film 24 is removed and a silicon substrate 23 of te same size as the silicon substrate 21 is overlapped and then joined together. The precision of the width (dp) of the opening 25 depends on the printing accuracy of a mask, thus enabling the availability of an extremely high precision nozzle.

Glass body provided with alkali diffusion preventing silicon oxide film

Abstract: PURPOSE: To obtain a glass body having increased power of hindering the diffusion of alkali from the glass by forming an alkali diffusion preventing silicon oxide film contg. hydrogen bonded to silicon on the surface of glass contg. alkali. CONSTITUTION: On the surface of glass contg. alkali an alkali diffusion preventing silicon oxide film inhibiting the diffusion of alkali from the glass is formed. At this time, to the silicon oxide film is added hydrogen bonded to silicon. The reason that the glass is provided with increased power of hindering the diffusion of alkali from the glass by the silicon oxide film is considered to be that -Si-H bond is introduced into part of -O-Si-O- bond in the silicon oxide film to make the network structure of the film dense, terminal H is positively charged to prevent the transfer of alkali ions such as Na + and K + , and the density difference between the glass and the material of the film coated on the glass surface or an electrical factor is caused, whereby the effusion of alkali ions to the glass surface is prevented. COPYRIGHT: (C)1983,JPO&Japio

Purifying method for alpha-type silicon nitride

Abstract: PURPOSE: To remove iron, calcium, silicon and silicon oxide as impurities from fine α-type silicon nitride powder by treating the powder with a mineral acid having a prescribed concn. or by further treating the treated powder with a mixed acid consisting of hydrofluoric acid and nitric acid under heating. CONSTITUTION: An aqueous soln. of a mineral acid having ≥5% concn. is added to fine α-type silicon nitride powder, and the powder is treated under heating. The soln. is then separated from the treated powder. After further adding an aqueous soln. of a mixed acid consisting of hydrofluoric acid and nitric acid to the powder, the powder may be treated again under heating. Thus, iron, calcium, silicon and silicon oxide as impurities are removed from the α-type silicon nitride. COPYRIGHT: (C)1983,JPO&Japio

Ortho-methylation of phenolic compound

Abstract: PURPOSE:To carry out the ortho-methylation reaction of a phenol compound with methanol using a highly active, highly selective and long-life catalyst containing vanadium oxide, molybdenum oxide and silicon oxide CONSTITUTION:A phenol compound, having a hydrogen atom at the ortho-position, of the formula (R1-R4 are H or alkyl) and methanol are subjected to the vapor phase catalytic reaction at 250-500 degC using a catalyst containing vanadium oxide, molybdenum oxide and silicon oxide, to give a phenol compound methylated at the ortho-position The atomic ratios in the catalyst are preferably V:Mo:Si= 100:(0-2):(1-70) The catalyst is prepared from vanadium oxide, chloride, etc, a molybdenum oxide, chloride, etc, and sodium silicate, etc by mixing, precipitation or evaporation to dryness etc followed by calcination at 300-600 degC USE:For example, raw material of a heat-resistant polymer, polyphenylene oxide

Semiconductor mesa contact with low parasitic capacitance and resistance

Abstract: Method of manufacturing silicon mesa diodes from a wafer of silicon. The surface of the wafer is coated with a first layer of silicon nitride and a second layer of silicon oxide. By masking and etching procedures, silicon nitride is left only on the portions of the surface defining the mesas to be formed. The wafer is etched to form the mesas and then treated to form a passivating silicon oxide coating at all the exposed surfaces of the wafer. The silicon nitride is removed from the upper surfaces of the mesas and metal contacts are applied to these upper surfaces. The wafer is subsequently divided into discrete dice, each containing a mesa, and the dice are mounted in suitable enclosures.

Method for manufacture of orthomethylated phenol compounds

Abstract: Manufacture of orthomethylated phenol compounds by the reaction of phenol compounds having a hydrogen atom at the ortho position and methanol is accomplished advantageously by a method which effects the reaction by use of a catalyst comprising (A) iron oxide, (B) indium oxide, and (C) at least one member selected from the group consisting of chromium oxide and silicon oxide According to this method, the reaction permits the orthomethylated phenol compound to be produced in high yields for a long time because of the catalyst's excellent activity-retaining property Since the ortho-position selectivity and the utilization ratio of methanol are high and, consequently, the utilization efficiency of raw materials is high, the method of this invention produces the orthomethylated phenol compound with high efficiency from the phenol compounds

Compound etching method

Abstract: PURPOSE:To prevent a side-etching as well as to smoothen corner sections by a method wherein an isotropic etching processing and a non-isotropic processing are cojointly performed as a compound etching method. CONSTITUTION:A silicon nitride film 2 of approximately 1.2mum is formed on the surface of a silicon substrate 3 using a vapor-phase growing method and the like, and a silicon oxide film 1 of 0.2mum or thereabouts is formed on the surface of the film 2. Then, a prescribed photoresist film is formed on the surface of the silicon oxide film 1, and a master pattern is obtained by performing an etching on the silicon oxide film 1. The silicon nitride film 2 is etched to the middle part using thermal phosphoric acid, and then the remaining part of the silicon nitride film 2 is removed by performing a reactive etching using CF gas. Accordingly, the silicon nitride film 2 can be etched as per master pattern, the corner of the pattern edge is steppingly formed, and a smooth sectional form can be obtained.

Preparation of phenol, derivative thereof or the like

Abstract: PURPOSE:To obtain a phenol, biphenyl, bibenzyl, aromatic aldehyde and ketone compound under ordinary temperature and pressure by the photochemical reaction of a compound having an aromatic ring in the presence of O2 and water and a specific semiconductor as a catalyst with irradiation of light. CONSTITUTION:A semiconductor having a band gap <=0.5lV as a catalyst is dispersed in water, and a compound having an aromatic ring expressed by formulaIor II (A1-A6 are substituent groups, e.g. OH, and alkyl such as CH3 or C2H5 or vinyl, allyl, phenyl, etc. having an unsaturated bond, OCH3, NO, halogen, etc.; the groups adjacent to A1-A6 are linked to form a polycyclic compound) is added thereto. The resultant mixture is then irradiated with light in the presence of oxygen to carry out the photochemical reaction and give the aimed compound. Titanium, oxide, barium titanate, zinc oxide, silicon oxide, etc. may be used alone as the semiconductor; however, palladium oxide, ruthenium oxide, Pt, Ni, etc. may be present for enhancing the oxidation reduction ability.

Effect of Ion Irradiation on the Formation of Ni, Cr and Pt Silicide

Abstract: The influence of Xe+, As+ and Si+ irradiation on the Ni, Cr and Pt-silicide formed upon subsequent thermal annealings has been investigated. Helium MeV backscattering spectrometry and x-ray diffraction have been used to analyze the samples. The effect of silicon-metal interface contamination has been observed using an intentionally formed thin silicon oxide layer. The oxide layer was thick enough to prevent thermal suicide formation in unirradiated samples. In irradiated samples, the suicide forms thermally in spite of the presence of this oxide layer for Ni and Cr, but not for Pt. Similar results were obtained for Xe+, As+ and Si+ irradiations. We attribute this effect to ion mixing of the interfacial layer. The differences between results obtained with Ni, Cr and Pt are discussed. These results demonstrate that a low-dose irradiation can render the process of suicide formation upon thermal annealing tolerant to interfacial impurities. On the other hand, we also show that ion irradition can inhibit Pt and Ni suicide formation.

Method of making strain sensor in fragile web

Abstract: A method of making a strain gauge in a fragile web wherein the improvement resides in making the web after the gauge is substantially completely formed. This reverse sequence is made possible by a unique combination of plasma deposited silicon oxide and plasma deposited silicon nitride on top of the completed device to protect it from attack during silicon substrate etching to form the diaphragm.

Method for obtaining an abrasive coating

Abstract: A method of preparing an abrasive silicon oxide coating on a substrate which includes glow discharging silane and N 2 O in the presence of a substrate whereby a first silicon oxide layer having a refractive index of between about 1.0 and 1.2 as measured by ellipsometry is deposited. A second silicon oxide layer having a refractive index of between about 1.30 and 1.48 as measured by ellipsometry is glow discharge deposited onto the first layer.