Showing papers on "Field effect published in 1971"
TL;DR: In this paper, the effect of surface states on the semiconductor is considered and it is shown that the band bending is exponentially dependent on distance from the surface and the modulation of the surface conductance as a function of transverse field, geometry, and surface state density is calculated.
Abstract: The Cohen–Fritzsche–Ovshinsky model for amorphous covalently bonded semiconductors is used to calculate the electrical characteristics of a field-effect structure utilizing an amorphous covalent film as the semiconductor. The effect of surface states on the semiconductor is considered. The analysis shows that the band bending is exponentially dependent on distance from the surface. The modulation of the surface conductance as a function of transverse field, geometry, and surface-state density is calculated. These calculations indicate that the field effect should be measurable for surface-state densities up to 1.5×1014 cm−2 (eV)−1. The results of these calculations should be used in the design of field-effect experiments in order to achieve the maximum sensitivity.
25 citations
TL;DR: In this paper, a strong magnetic field dependence was found for the conductivity of n-type InSb in the temperature range 0.27-4.2 K and in magnetic fields up to 10 kG.
Abstract: Electrical conductivity measurements on n-type InSb in the temperature range 0.27-4.2 K and in magnetic fields up to 10 kG have been made. The results indicate a strong magnetic field dependence for the conductivity, with an activation energy depending on magnetic field. These results are discussed in the light of the recently proposed wigner transition which is appropriate to the highly compensated samples used in this work. The magnitude of the activation energy and the role of the first excited state of the impurity centre are also briefly considered.
21 citations
TL;DR: GaAs single crystals real surface electrical characteristics, using pulsed field effect techniques, were used in this paper to evaluate the electrical properties of GaAs single-crystal single crystals.
21 citations
Patent•
28 Dec 1971TL;DR: In this paper, a field effect semiconductor switching device of high breakdown voltage and large current capacity having negative resistance characteristics which are controllable by an electric field is presented, which can be used as a switching device.
Abstract: A field effect semiconductor switching device of high breakdown voltage and large current capacity having negative resistance characteristics which are controllable by an electric field.
20 citations
TL;DR: In this article, conductivity modulation was observed in thin films of chalcogenide glass by applying an electric field through the (mica or plastic) substrate, in agreement with the Seebeck coefficient.
Abstract: Conductivity modulation was observed in thin films of chalcogenide glass by applying an electric field through the (mica or plastic) substrate. At room temperature, the surface potential could be varied through ± 3kT, the surface being always p type, in agreement with the Seebeck coefficient. Comparison of the field‐effect curves with equilibrium space‐charge theory suggests a bulk density of localized states in the range from 1019 to 2 × 1020 cm−3 eV−1 within ± 0.1 eV of the Fermi level.
19 citations
Patent•
21 Dec 1971
TL;DR: In this paper, an electron gun uses a field effect emitter in a vacuum tube, providing the advantages of cold cathode emission at atmospheric temperature in addition to a simplified control system.
Abstract: An electron gun uses a field effect emitter in a vacuum tube, providing the advantages of cold cathode emission at atmospheric temperature in addition to a simplified control system. Temperature independent emission is achieved by using an oxidemetal composite emitter for releasing electrons. The anode and emitter can be shaped to produce a desirable electric field and current path for special electron tubes.
18 citations
Patent•
24 May 1971
TL;DR: In this article, a potential extremum is generated in the channel by illumination and its shift is used as vehicle for minority carrier transport, where photo-sensitive field effect transistors are integrated with minority carrier sensors.
Abstract: The invention concerns improved semiconducting light sensors based on field effect transistor structures. A potential extremum is generated in the channel by illumination and its shift is used as vehicle for minority carrier transport. Photosensitive field effect transistors are integrated with minority carrier sensors.
18 citations
Patent•
17 Dec 1971
TL;DR: A unique electron source comprises an oxide-metal composite capable of emitting electrons at ambient temperatures when subjected to an electric field and thermionic emission is not employed during any stage of emission as mentioned in this paper.
Abstract: A unique electron source comprises an oxide-metal composite capable of emitting electrons at ambient temperatures when subjected to an electric field. The quantity of electrons emitted depends on the electric field provided for the emitter and thermionic emission is not employed during any stage of emission. The electron source, a field effect emitter, can have more than a million metal fibers for each square centimeter of emitter surface area. The metal fibers are normally less than one micron in diameter and are uniformly embedded within an oxide insulator for emitting electrons from the ends of the metal fibers.
17 citations
Patent•
25 Jun 1971TL;DR: In this article, an insulated gate type field effect transistor with a source, drain and a clamping diode region of P conductivity type formed in an N conductivity types silicon substrate and a low resistivity region of N conductivities in the substrate surface except in the channel region.
Abstract: An insulated gate type field effect transistor having a source, a drain and a clamping diode region of P conductivity type formed in an N conductivity type silicon substrate and a low resistivity region of N conductivity type formed in the substrate surface except in the channel region so as to bridge the source region and the clamping diode region.
14 citations
TL;DR: Inversion of the surface conductance from a p-type accumulation layer was achieved with external fields of about 10 6 V/cm as discussed by the authors, where the density and energy of surface states were estimated.
13 citations
TL;DR: In this paper, the anomalous term becomes twice as large as the Aslamazov-Larkin term independenct of the dimensionality of the system and independent of the pair-breaking parameter iJ.
Abstract: The nonlinear field dependence of the so-called anomalous term in the electric conduc tivity due to the fluctuation of the superconducting order parameter is studied theoretically. It is found that in the limit of a large electric field E (i.e. E'J:>Ec= y3/D s0(T)312je where c0 (T) =8/n(T-Tc) and D is the diffusion constant), the anomalous term becomes twice as large as the Aslamazov-Larkin term independenct of the dimensionality of the system and independ~nt of the pair-breaking parameter iJ.
TL;DR: In this article, the electronic surface properties of as-grown or cleaved single crystals of cadmium selenide have been studied using surface conductivity, field effect and Volta potential difference measurements carried out under vacuum and under a controlled oxygen pressure.
Patent•
27 Sep 1971
TL;DR: In this article, a distribution of charges is accumulated over a leaky dielectric layer in response to electrons from a microchannel plate, which amplifies the output of a photocathode layer stimulated by optical image information.
Abstract: A distribution of charges is accumulated over a leaky dielectric layer in response to electrons from a microchannel plate, which amplifies the output of a photocathode layer stimulated by optical image information. Each respective element of an array of field-effect elements, coextensive with the charged dielectric and adjacent to the surface of the dielectric opposite the microchannel plate, is differently modulated in conductivity by the local field due to the local charge on the portion of the dielectric adjacent the respective element. Readout by periodic scanning of the level of conductivity of each such element results in a modulated output signal suitable for the reproduction of the optical image information in amplified form.
Patent•
17 Jan 1971
TL;DR: In this article, the authors proposed a method of interfacing between bipolar and field effect devices utilized complementarily in logic circuits, which provides compatibility virtually at all times between the switching levels for the bipolar and FET devices and accomplishes this by providing source bias to the field effect transistor deriving input from the bipolar device, thereby effectively raising the turn-on voltage of the FET.
Abstract: The invention relates to a method of interfacing between bipolar and field effect devices utilized complementarily in logic circuits. The invention provides compatibility virtually at all times between the switching levels for the bipolar and field effect devices and accomplishes this by providing source bias to the field effect transistor deriving input from the bipolar device, thereby effectively raising the turn-on voltage of the field effect transistor.
TL;DR: In this paper, a transient and steady-state electric field effect was observed at a freshly cleaved ab-surface of a single crystal, where naphthacene was removed from the crystal surface to suppress the field effect.
TL;DR: In this article, electric charges were induced in thin bismuth films by an electric field applied normal to the sample surface and the change in the electrical conductivity due to the field effect was interpreted using the Fuchs-Sondheimer and McIrvine theories.
TL;DR: In this paper, a new technique was described for determining the surface barrier height in large-gap semi-conductors, which was picked up by superimposed surface photovoltage measurements.
Patent•
11 Feb 1971TL;DR: In this article, a technique for the fabrication of a self-registered gallium arsenide field effect structure including at least one semi-insulating surface layer is described, which involves forming a semiinsulating layer including a surface coating on a conductive material upon the surface of n-type gallium arsenicide, generating a pair of windows in such layer and introducing either a p-type or n -type material through the windows.
Abstract: A technique is described for the fabrication of a self-registered gallium arsenide field effect structure including at least one semi-insulating surface layer. The technique involves forming a semi-insulating layer including a surface coating on a conductive material upon the surface of n-type gallium arsenide, generating a pair of windows in such layer and introducing either a p-type or n-type material through the windows.
TL;DR: In this paper, the changes of the conductivity, the Hall coefficient, and the transverse magnetoresistance due to the field effect are measured on thin InSb samples between 78 and 295° K.
TL;DR: In this article, a new and highly sensitive strain transducer was developed using a thin-film semiconductor deposited on a polished piezoelectric ceramic substrate, where the number of mobile carriers in the semiconductor is dependent on the electric-displacement vector of the substrate.
Abstract: A new and highly sensitive strain transducer has been developed using a thin-film semiconductor deposited on a polished piezoelectric ceramic substrate. Field-effect coupling has been found to exist between the substrate and film in which the number of mobile carriers in the semiconductor is dependent on the electric-displacement vector of the substrate. Therefore, the conductivity of the semiconducting film can be altered by piezoelectric charge due to a strain applied to the substrate material. An effective gage constant has been calculated in terms of the piezoelectric and elastic constants of the substrate and electronic properties of the film. Experimental devices were constructed by depositingp type tellurium on polished lead-zirconate-titanate ceramic resulting in experimentally observed gage factors as high as 5800 compared to 100–200 for conventional semiconductor gages. The semiconductor film exhibits an electronic instability that limits its use, at present, to transient measurements with frequencies above 1 Hz. Data will also be presented to show that the gage constant is continuously variable between a positive and negative maximum value by altering the magnitude and direction of the substrate-polarization vector. It is believed that these gages will be useful in those cases where extremely small strains (∼10−7) are to be measured or when moderate strains (∼10−4) are to be determined in an electrically noisy background.
TL;DR: In this paper, the surface conductivity and effective mobility were studied as functions of the surface potential on CdSe single-crystal films having a conductivity of 1−10−5 Ω.
Abstract: The surface conductivity and effective mobility were studied as functions of the surface potential on CdSe single-crystal films having a conductivity of 1–10−5 Ω.cm−1. The surface potential was varied by a constant external field. The formation of a conducting channel at the film surface is governed primarily by the change in the trapping factor as volume traps near the surface are filled. Field-effect data are used to evaluate the parameters of the exponential distribution of volume traps with respect to energy, the effective concentration of small donors, and the absolute values of the surface potential.