Showing papers on "Substrate (electronics) published in 1976"

Epitaxial structures with alternate‐atomic‐layer composition modulation

Abstract: Epitaxial structures grown by alternate monolayer depositions of GaAs and AlAs are reported. As many as 104 alternate (100) layers of GaAs and AlAs as thin as 1.0±0.1 and 1.0±0.1 monolayers, respectively, were deposited by sequential molecular beam epitaxial growth on a (100)GaAs substrate. Transmission electron microscopy showed the resultant films to be perfectly epitaxial with layered composition modulation of the expected periodicity. Their electronic properties were studied by optical absorption and luminescence.

Zinc-oxide thin-film surface-wave transducers

Abstract: The piezoelectric film layer transducer represents the most efficient method for generating and detecting surface acoustic waves on nonpiezoelectric substrates. ZnO, which has a strong piezoelectric effect and can readily be sputtered as an oriented crystalline composite on a wide variety of substrates, is a natural choice as the piezoelectric film layer. This paper summarizes a body of knowledge which has been developed on the characteristics of transducer quality ZnO film layers, and focuses attention on those sputtering parameters and microstructural properties which characterize a superior surface-wave transducer film. Requisite sputtering conditions are high substrate temperatures (150-300°C), modest deposition rates (0.5-1.0 µm/h), low background vapor pressures (<5 µm Hg) and an ultraclean vacuum system. Transducer quality surface-wave films are characterized by their optical clarity, high density, smooth surface, small crystallite size, and well-oriented crystallite axes. Such ZnO films will play an important role in future surface acoustic wave device technology.

Single crystals of germanium and silicon&#8212;Basic to the transistor and integrated circuit

Abstract: HEN the transistor was discovered at Bell Laboratories there were few even within the Labs who knew about it for some months due to a decision of management to maintain close security for a period. John Bardeen and Walter Brattain [l], [2] made their earthshaki:ng observations on December 23,1947; the first public demo’nstration of the invention and announcement of the discovery was not made until June 30,1948. In the interim period only those who were assigned to the project by research management were told the facts. I was at Bell Labs at this time and had been there for many years. Though I was not in the physics semiconductor group, I learned a bit about the invention in the early part of 1948, due to my having deposited pyrolytically. silicon, germanium, and germanium-silicon alloy films on ceramic tubes during World War 11. Some of these experimental samples turned out to be of interest to Shockley in trying some of his ideas of how to make a field-effect tramistor. Bardeen and Brattain’s discovery was very exciting news, perhaps even more so for me than for many others because I had long nourished an interest in germanium. that had started with my undertaking graduate study a t Brown University under Prof. Charles A. Kraus, American Chemical Society president, and Willard Gibbs, Franklin and Priestley Medalist, who was one of the two outstanding U. S. experts on germanium at that ime. My master’s and doctor’s theses were on germanium. It was a material studied only for its scientific interest; its complete uselessness fascinated’ and challenged me. My concentration on this shiny metallic-appearing material during my graduate school days resulted in a continuing personal sentimental attachment for germanium, which, to me, a t least, was and is an exotic element. This deep but little known personal attachment influenced me from time to time over an eighteen-year period after leaving Brown University to seek some way of capitalizing on this knowledge and interest acquired years before. The opportunity to enter a career of creative research and innovation, concerned particularly with electronic materials, I owe to Dr. Robert R. Williams and Dr. Robert M. Burns, who headed Bell Labs chemical research. When they invited me to come to work at Bell Laboratories, I accepted and went there in 1930. M.y initial studies a t Bell began as a member of the Chemical Research Department. In 1933 I transferred to the Electro-Optical Department reporting to its head,

Duplex coating for thermal and corrosion protection

Abstract: A duplex coating and method for making same wherein a primary layer of metals or metal alloys is deposited on a superalloy substrate to seal the substrate against oxidation. A second layer of low density oxide is deposited on the surface of the primary layer. The primary layer has a rough surface so as to provide an adherent surface for the oxide layer.

Morphological and electrical properties of rf sputtered Y2O3‐doped ZrO2 thin films

Abstract: The structural, compositional, and electrical properties of rf sputter‐deposited Y2O3‐doped ZrO2 films have been investigated as a function of sputtering conditions. The results show that the application of an rf substrate bias during deposition has a large effect on both the morphological and electrical properties of the films. Auger electron spectroscopy, electron diffraction, and scanning‐electron‐fractography results show that films deposited at P=20 mTorr (2.67 Pa), VT=−500 V, and VS=−40 V are nearly stoichiometric, have a cubic crystal structure, and a relatively equiaxed microstructure. The results of electrical measurements indicate that films grown under these sputtering conditions have an ionic transference number which is nearly zero below 100 °C and rises to approximately 0.4 at 200 °C.

Process for forming monocrystalline silicon carbide on silicon substrates

Abstract: A method for forming monocrystalline silicon carbide on a silicon substrate by converting a portion of the monocrystalline silicon substrate into a porous silicon substance by anodic treatment carried out in an aqueous solution of hydrofluoric acid, heating the resultant substrate to a temperature in the range of 1050° C to 1250° C in an atmosphere that includes a hydrocarbon gas for a time sufficient to react the porous silicon and the gas, thereby forming a layer of monocrystalline silicon carbide on the silicon substrate.

MIS semiconductor device and method of manufacturing the same

Abstract: A metal-insulator semiconductor (MIS) device is manufactured by initially forming, on a semiconductor substrate, an insulating film having a hole therethrough and depositing silicon on the substrate to form a first monocrystalline silicon film in the hole and a polycrystalline silicon film on the insulating film. Then, a further insulating film is formed on the first silicon film, and a second silicon film is formed on the further insulating film. The second silicon film and the further insulating film are removed, so that the monocrystalline and polycrystalline parts of the first silicon film are exposed at both sides of the remaining part of the second silicon film and the further insulating film. Finally, an impurity is diffused to form a source and a drain region in the monocrystalline silicon film and conductive layers of polycrystalline silicon are disposed contiguous to the source and drain regions.

Transparent conductive Sn‐doped indium oxide coatings deposited by reactive sputtering with a post cathode

Abstract: A dc post‐cathode sputtering apparatus with magnetic plasma containment that (1) minimizes substrate plasma bombardment, (2) is operable over a wide working‐gas pressure range, and (3) is scalable to large areas was used to reactively sputter indium–tin oxide coatings (3000–15 000 A thick) onto glass and quartz substrates at various substrate temperatures (20° to 400 °C) and oxygen pressures (0.04–4 Pa). Resistivity, optical transmission and reflection, refractive index, surface topography (by SEM), and crystal structure (by x‐ray diffraction) determinations were made both for as‐deposited coatings, and also as a function of heat treatment in air and forming gas. X‐ray diffraction measurements on coatings approximately 10 000 A thick yielded crystalline structures in the as‐deposited and heat‐treated states. The as‐deposited coatings exhibited relatively high resistivities. Coatings deposited at moderate pressures and then heat treated yielded electrical and optical properties similar to those reported by...

Laser for integrated optical circuits

Abstract: Semiconductor laser of electrically pumped type comprising a substrate of III-V compound semiconductor material or mixed ternary III-V semiconductor composition having a mesa structure provided with a p-n junction between regions of opposite conductivity therein. An electrical power source is connected to the mesa and upon activation causes the injection of minority carriers across the p-n junction, such that laser radiation is produced from the p-n junction.

Method of manufacturing a semi-insulating silicon layer

Abstract: Silicon ions are implanted in a silicon dioxide layer on a silicon substrate so that the dioxide layer is converted into a semi-insulating layer having an improved passivation property.

Metalorganic chemical vapor deposition of IVA-IVA compounds and composite

Abstract: A composite comprising a monocrystalline substrate and one or more layers or films of monocrystalline IVA-VIA compounds and/or alloys formed thereon by a chemical vapor deposition process. The composite is formed at a preferred temperature range of approximately 450°-650° C. The IVA-VIA layer(s) are produced by the pyrolysis of a gas mixture containing metalorganic compounds. Where single crystal metallic oxide substrates of rhombohedral structure, such as sapphire, (α-Al 2 O 3 ), or of cubic structure, such as magnesium aluminate (spinel), are used for the growth of monocrystalline lead-containing films such as Pb 1-x Sn x Te, a nucleation layer of lead is preferably formed on the substrate prior to the pyrolysis of the mixed gaseous reactants. Using the present process, epitaxial monocrystalline IVA-VIA compounds and/or alloys can be grown on inorganic metal oxide substrates, such as cubic and rhombohedral oxides, on alkali halides and IIA fluorides, and on II-VI and III-V compounds. The compositions of the films can be varied without removing the composites from the deposition apparatus by changing the ratio of the reactant gases and the reaction temperature. The conductivity type (n-type or p-type) of the films also can be controlled without removing the composites from the deposition apparatus by varying the reactant gas compositions and by incorporating a dopant into the reactant mixtures prior to pyrolysis.

Silicon carbide filaments and method

Abstract: A refractory substrate, which generally is graphite or carbon is overcoated with silicon carbide by chemical vapor deposition from gaseous sources of silicon and carbon. The deposition generally takes place in combination with hydrogen and the coating on the substrate generally has a thickness at least equal to the diameter of the substrate itself. A silicon carbide filament containing an inner and outer surface layer of carbon rich silicon carbide, together with a method of making the same, is described.

Substrate Current due to Impact Ionization in MOS-FET

Abstract: The substrate leakage current vs. gate voltage characteristics of MOS-FET was examined over a wide range of device parameters and measurement conditions. With the increase in the gate voltage, the substrate current increases until it reaches a maximum value. Then it decreases to the value of the generation-recombination current. The substrate current has a high value at low measurement temperatures, high drain voltages, high impurity concentrations of silicon substrates, thin gate-oxide thicknesses and a large drain current. These experimental results were semi-quantitatively explained on the basis of a model in which the substrate current is caused by the first-order impact ionization of the carriers within the pinched-off region. The observed increase of the substrate current is mainly dominated by an increase of the drain current, and the decrease of the substrate current is mainly dominated by a decrease of the impact ionization coefficient.

Superintegrated v-groove isolated bipolar and vmos transistors

Abstract: The invention concerns a semiconductor structure having a compatible mixture of bipolar and unipolar transistors. In that structure a monocrystalline p-type silicon substrate is employed which has its 1-0-0 crystallographic planes at a face on which an n epitaxial layer was grown. The epitaxial layer is divided into electrically isolated parts by V-grooves that extend down through the epitaxial layer and have their apices terminating in the substrate. A thin silicon dioxide film coats the V-grooves and those grooves are filled with polycrystallie silicon. Where it is desired to use the polycrystalline silicon as the insulated gate of a field effect transistor, the polycrystalline silicon is electrically conductive. Bases for bipolar transistors are formed by diffusion of an appropriate impurity into selected areas of the epitaxial layer. The emitters, drains, and sources are formed by diffusion of a different impurity. Each field effect transistor has its drain and source on adjacent parts of the epitaxial layer which are separated by the V-groove in which the gate is situated. The base and emitter of a bipolar transistor may be situated on one isolated part and the collector may be situated on an adjacent part separated by a V-groove having an electrically conductive polycrystalline filler.

Growth of vacuum‐deposited tellurium films on glass substrates and some of their transport properties

Abstract: The influence is investigated of film thickness, substrate temperature, and evaporation rate on preferred orientation and degree of crystallite order of tellurium thin films deposited in vacuum on glass substrates. Based on these dependences together with the determination of critical film thickness dependence and relative condensation coefficient on substrate temperature, the growth model of tellurium thin films is described. The preferred orientation of (hk0)-type is found to be mainly influenced especially by the substrate temperature and deposition rate. The results are compared with those obtained by electron microscope observation of Te-film surfaces. The results of the structure and growth investigations of Te films are supplemented by measuring some of their transport properties. [Russian Text Ignored]

Chemical vapor deposition methods of depositing zinc boro-silicated glasses

Abstract: An alkyl compound of zinc is reacted with alkyl compounds or alkoxyl compounds of boron and silicon in the presence of oxygen, thereby to deposit on a substrate zinc borosilicate glass film through a chemical vapor deposition process. The outlet nozzle of a raw material supply conduit for introducing the raw material compounds into a reaction zone is opened in the direction substantially in parallel with a surface of the substrate on which the glass film is to be deposited so that raw materials may be well mixed at the reaction zone. The glass film thus produced has a uniform thickness and a homogeneous composition of the constituents over an area at least of 40 mm extending from the nozzle and is suited for use as protection films for semiconductor devices and dielectric layer for a thin film capacitor on an industrial base.

Process for producing large-size, self-supporting plates of silicon

Abstract: Process for producing large-size, self-supporting plates of silicon deposd from the gaseous phase on a substrate body, which comprises heating a graphite substrate to deposition temperature of silicon, which is deposited on the substrate from a gaseous compound to which a dopant has been added until a layer of about 200 to 650 μm has formed, subsequently melting 40-100% of this layer from the free surface downward, resolidifying the molten silicon by adjustment of a temperature gradient from the substrate body upward, and finally separating the silicon therefrom. The plates so formed are used primarily for making solar cells.

Multitarget sputtering using decoupled plasmas

Abstract: A method is developed for quantitatively predicting the chemical composition and thickness distributions of alloy films deposited by decoupled‐plasma multitarget rf sputtering in which the substrates rotate at a variable rate through separate glow discharges. The film thickness distributions deposited from each target are expressed in terms of deposition variables such as applied target voltage, target radius, sputtering pressure, substrate rotation radius, rotation rate, and target‐substrate separation. Predicted films thickness distributions were found to be in agreement with experimental results in which β backscattering was used to measure the thickness of InSb films deposited on both stationary and rotating substrates. Using deposition parameters determined from the model presented in this paper, single‐phase In1−xGaxSb alloy films were grown whose experimentally determined compositions agreed with predicted values. Intercalated films with layer thicknesses of less than 100 A and films which were che...

Molecular Beam Epitaxy of GaP and GaAs1-xPx

Abstract: GaP and GaAs1-xPx single crystal thin films were successfully grown on (100)-oriented GaP substrates by molecular beam epitaxy. At lower substrate temperatures these materials have a tendency to grow in pyramidal forms. However, at substrate temperatures of 560~600°C, single crystalline films with high crystallographic quality and flat surfaces are grown at the intensity ratio of molecular beams, P/Ga, of about 100. The composition ratio x of GaAs1-xPx is dependent on the substrate temperature, Ts, and the intensity ratio P/As. The rate of decrease, -dx/dTs, is found to be 0.003°C-1 for the entire composition-ratio range.

Method for forming a narrow channel length MOS field effect transistor

Abstract: A method for fabricating an N-channel silicon MOS field effect transistor on a P-type substrate. The structure retains the natural isolation between devices and the consequent higher device density in an integrated circuit structure than conventional double diffused MOS field effect transistor devices. The device is fabricated by using ion implantation to create an N-type surface layer in the channel and then overcompensating this layer to create a P-type region near the source by ion implanting P-type ions into the source junction region. The source to substrate capacitance is considerably less than that of conventional double diffused MOS devices which provides an improved circuit performance.

Fabricating high performance integrated bipolar and complementary field effect transistors

Abstract: FABRICATING HIGH PERFORMANCE INTEGRATED BIPOLAR AND COMPLEMENTARY FIELD EFFECT TRANSISTORS ABSTRACT A method for making dielectrically isolated bipolar and field effect transistors in the same substrate and a semiconductor integrated circuit so-made. The method consists of forming a first region of one conductivity type in a monocrystalline semiconductor substrate on a first type, forming second and third regions having different diffusion rates in the substrate, forming a monocrystalline layer of the other conductivity type, adding impurity to the second region, depositing a dielectric layer over the monocrystalline layer, forming openings in the dielectric layer over the first and third regions and another location in the monocrystalline layer, and depositing a layer of silicon over the dielectric layer and the openings. The impurities in the third region are outdiffused into the monocrystalline region over it to form the channel region of a Field Effect transistor. The regions of the layer of silicon are dielectrically isolated from one another and emitter and base regions of a bipolar transistor are selec-tively formed in the monocrystalline region over subcollector regions. Source and drain regions for a field effect transistor are formed over the third region and the another location to form both channel types of field effect transistors.

Method for depositing continuous pinhole free silicon nitride films and products produced thereby

Abstract: A substrate article coated with a pinhole free film of silicon nitride produced by reacting silane with a nitrogen containing compound which upon decomposition produces nascent nitrogen and sufficient amounts of a carrier gas that is inert to the reactants and heating said substrate to a temperature above about 500° C to cause the deposition of silicon nitride film on said substrate.

Semiconductor device having a hetero junction

Abstract: A semiconductor device comprising a silicon substrate with an oxygen doped polycrystalline or amorphous silicon layer formed on the substrate so as to form a hetero junction therewith. A transistor formed according to the invention has an emitter-base hetero junction and has a high current gain.

Method of manufacturing apertured aluminum oxide substrates

Abstract: A method for making an apertured aluminum oxide substrate by selectively masking a sapphire wafer, depositing aluminum oxide adjacent the wafer and the mask, and removing the aluminum oxide deposited adjacent the mask and the mask, whereby an aperture is formed in the aluminum oxide. A composite is thus formed of an insulating substrate of monocrystalline sapphire with an insulating epitaxial layer of aluminum oxide apposed thereto, the epitaxial layer having an aperture therein which may be filled with an island of epitaxial silicon.

Method for making schottky barrier diodes

Abstract: A plurality of Schottky barrier devices are produced by a method which uses a relationship between barrier height, surface concentration of impurities, and alloying time valid when a thin layer of oxide is present on a device substrate and includes the steps of preselecting an impurity concentration for the principal surface of a plurality of silicon substrates and using a predetermined alloying time for each substrate to achieve a preselected barrier height.

Si3 N4 Coated crucible and die means for growing single crystalline silicon sheets

Abstract: Mechanical components, e.g. die and/or crucible or the like structures with which single silicon crystals are grown from the melt as shaped articles in thin sheet or ribbon geometry, are advantageously comprised, for their material of construction, of a suitable thermally stable and inert foundation substrate coated or provided on at least the silicon-contacting surface(s) thereof with a thin, uniform, integral surface layer deposit of pyrolitic silicon nitride (Si3 N4) obtained by the chemical vapor deposition (i.e., "CVD") technique.

Integrated optical silicon photodiode array

Abstract: We consider device design, fabrication, and operation of integrated optical photodiode arrays in which p-i-n junction photodiodes are formed in silicon. A SiO2 layer on silicon serves as the effective substrate for a KPR waveguide. Light is coupled from the waveguide at the detector region either through the evanescent field or by multiple refraction into the detector. The waveguide–photodiode structure is designed so that nearly 100% of the incident optical energy can be absorbed in the photodiode junction depletion region. A device quantum efficiency of 80% is measured compared to a theoretical value of 93%.