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Showing papers on "Thin-film transistor published in 1976"


Journal ArticleDOI
TL;DR: In this article, the volt-ampere characteristics for a thin film transistor fabricated with vacuum-deposition amorphous silicon as the semiconductor are presented and experimentally verified using the Cohen-Fritzsche-Ovshinsky model.
Abstract: The volt-ampere characteristics for a thin film transistor fabricated with vacuum deposited amorphous silicon as the semiconductor is presented. The substrate is single crystalline silicon with a 3000 A layer of thermally grown silicon dioxide as the insulator. The gate is a buried N+ phosphorus diffused region while the source and drain contacts are interdigited fingers of aluminum. By using the Cohen-Fritzsche-Ovshinsky model for the density of localized states in the mobility gap, the VG vs ID characteristic at small values of VD is predicted and experimentally verified. This characteristic is used to theoretically predict the family of ID curves for the TFT over a range of VG and VD. The theory and experiment agree exceptionally well below the gate-drain pinch-off, thereby verifying the theory of a TFT with a uniform distribution of traps in the band-gap.

46 citations


Patent
20 Aug 1976
TL;DR: In this paper, a double gated thin film field effect transistor (DGFET) was proposed, in which a thin layer of indium is provided on either side of the cadmium selenide conducting channel and after annealing enhances the transconductance of the device and reduces trapping of charge in the semiconductor.
Abstract: A double gated thin film field effect transistor in which cadmium selenide is the semiconductor material. A thin layer of indium is provided on either side of the cadmium selenide conducting channel and after annealing enhances the transconductance of the device and reduces trapping of charge in the semiconductor. The source and drain contacts of the device are a combination of an indium layer and a copper layer which improve the performance of the device.

44 citations


Journal ArticleDOI
TL;DR: The thin-film field effect transistor (t.f.t) as discussed by the authors can be formed on inexpensive substrates, such as glass and paper, and its future could lie in its use as a really cheap device of moderate performance, made with plant of low capital cost.

29 citations


Journal ArticleDOI
TL;DR: In this paper, a theoretical model for a polycrystalline film is proposed which takes account of the potential barriers at the intergrain boundaries and the band bending at the semiconductor/insulator interface.

29 citations


Patent
01 Jun 1976
TL;DR: In this article, a vertical transistor is formed in an N-type epitaxial layer overlying an N+ substrate by implanting P-type impurity in a location spaced apart from the surfaces of the epitaxia layer.
Abstract: An integrated transistor circuit arrangement provides a multicollector transistor with Schottky diodes and ohmic connections selectively formed at the collector terminals. In the illustrative example, a vertical transistor is formed in an N-type epitaxial layer overlying an N+ substrate. A through-extending region of P+ material encircles the region of the epitaxial layer in which the vertical transistor is formed. The base of the vertical transistor is formed by the implanting of P-type impurity in a location spaced apart from the surfaces of the epitaxial layer. The resulting base has a symmetrical profile relative to the faces of the epitaxial layer. Therefore, the transistor may be operated with the collector at the surface without penalty of electrical operation. In the illustrative example, a PNP lateral transistor is utilized as a current source for the vertical transistor.

22 citations


Patent
30 Dec 1976
TL;DR: In this paper, a method of making an improved aluminum oxide (sapphire) gate field effect transistor was proposed, wherein the capacitance-voltage characteristic of the transistor was improved by annealing the aluminum oxide at a temperature less than the growth temperature of the aluminum dioxide.
Abstract: A method of making an improved aluminum oxide (sapphire) gate field effect transistor wherein the capacitance-voltage characteristic of the transistor is improved by annealing the aluminum oxide at a temperature less than the growth temperature of the aluminum oxide. A transistor annealed at a temperature less than the growth temperature is provided wherein the threshold voltage is the same as if the transistor were annealed at a temperature greater than the growth temperature; the capacitance-voltage characteristic of the transistor exhibiting markedly diminished hysteresis by annealing at a temperature less than the growth temperature.

20 citations


Journal ArticleDOI
TL;DR: In this paper, a simple model for barrier-limited conductivity in a thin semiconductor film is extended to take account of the band bending at the semiconductor-insulator interface in thin-film transistor structures.

15 citations


Patent
09 Aug 1976
TL;DR: In this paper, a deep diode transistor includes at least one of the emitter, collector and base regions comprising recrystallized material of the semiconductor substrate embodying the transistor.
Abstract: A deep diode transistor includes at least one of the emitter, the collector and the base regions comprising recrystallized material of the semiconductor substrate embodying the transistor. Each region of recrystallized material is formed in situ by the migration of a melt of a metal-rich semiconductor material through the material of the substrate at a predetermined elevated temperature along a thermal gradient established in the substrate.

10 citations


Patent
29 Oct 1976
TL;DR: In this article, the vertical transistor is formed by auto-doping an epitaxial silicon layer for an improved transistor doping profile, which is achieved by the incorporation of Schottky diodes into the circuit.
Abstract: Merged transistor logic integrated circuit wherein the vertical transistor is formed by auto-doping an epitaxial silicon layer for an improved transistor doping profile. Further device improvements are achieved by the incorporation of Schottky diodes into the circuit.

10 citations


Journal ArticleDOI
TL;DR: In this article, an MOS transistor is described in which the source and drain areas are obtained by diffusion from doped polycrystalline silicon, and polysilicon tracks form the interconnect with the diffusion areas without the need for contact windows.
Abstract: An MOS transistor is described in which the source and drain areas are obtained by diffusion from doped polycrystalline silicon. Polysilicon tracks form the interconnect with the diffusion areas without the need for contact windows. As a result transistor and junction sizes are reduced by a factor 2 or 3 over a normal structure. Polycrystalline silicon tracks in this new technique are of greater advantage as interconnect layers than in the silicon gate tecgnique.

9 citations


Patent
24 Aug 1976
TL;DR: In this paper, a plurality of discrete transistor devices are produced on a semiconductor wafer and isolated from one another by moat etching, and a passivation layer is then deposited in the moats separating the discrete transistor device.
Abstract: A plurality of discrete transistor devices are produced on a semiconductor wafer and isolated from one another by moat etching. A passivation layer is then deposited in the moats separating the discrete transistor devices. The semiconductor wafer is then scribed and broken along lines delineated by the moats. The disclosed method permits testing of each discrete transistor device prior to separation from the wafer.


Patent
26 Nov 1976
TL;DR: An improved field effect transistor structure which reduces a leakage phenomenon, termed the "sidewalk" effect, between the semiconductor substrate and a conductive silicon dioxide layer disposed over the substrate is proposed in this article.
Abstract: An improved field effect transistor structure which reduces a leakage phenomenon, termed the "sidewalk" effect, between the semiconductor substrate and a conductive silicon dioxide layer disposed over the substrate. The improvement comprises forming a layer of highly resistive, silicon dioxide or silicon oxynitride, which is between the conductive oxide and the silicon nitride layer which forms a portion of the gate insulator for the field effect transistor.

Proceedings Article
01 Jan 1976

Journal ArticleDOI
TL;DR: In this paper, a thin-film field effect transistor (TFT) made in a laboratory using vacuum evaporation and photolithography is reported, and the different parameters are calculated.
Abstract: In this paper, Thin-Film Field Effect Transistor (TFT) made in our laboratory using vacuum evaporation and photolithography is reported. The different parameters are calculated. When two gates cover the same source and drain electrodes, the device with the gate near the connecting pads shows saturated characteristics, but the other device fails to saturate. A simple explanation based on surface states is given for this behaviour.

Journal ArticleDOI
TL;DR: In this article, the effect of flatbandvoltage variation along the channel as caused by the presence of mobile ions in the insulator and of slow surface traps in the semiconductor-insulator interface is investigated.
Abstract: The theoretical model for a thin film transistor (TFT) is extended to include the effect of a flatband-voltage variation along the channel as caused by the presence of mobile ions in the insulator and of slow surface traps in the semiconductor-insulator interface. The parameters determining the flatband-voltage in a common experimental situation are discussed. Finally, some approximations are given, resulting in a very simple model for the influence of mobile ions on the drain characteristics.

Book ChapterDOI
01 Jan 1976
TL;DR: Thin films of elemental semiconductors such as Si, and of passive dielectrics as discussed by the authors have already found widespread applications in solid state component technology and in high-density microelectronics.
Abstract: Thin films of elemental semiconductors such as Si, and of passive dielectrics, such as SiO2 and Si3N4, have already found widespread applications in solid state component technology and in high- density microelectronics. As preparative techniques develop, films of more complex semiconducting and insulating materials are receiving increased study and are gradually being incorporated in a variety of novel devices, both passive-and active. Many of these devices cannot yet be considered as part of the standard range of microelectronic components, and in fact their hybrid organization, and final structural form and function are still the subject of speculation and experimental development. The numerous innovations occuring in thin film devices are amply illustrated by recent work in fields such as microwave diodes and transistors, thin film transistors, infrared detectors, magnetic bubble memories, photovoltaic solar cells, microwave acoustics, capacitors and solid state imaging and display systems.

Journal ArticleDOI
01 Nov 1976
TL;DR: In this article, the expression for source-drain characteristics of a thin-film transister with linearly graded channel thickness is presented based on a depletion-type operating in an enhancement mode.
Abstract: The expression for source-drain characteristics of a thin-film transister with linearly graded channel thickness is presented based on a depletion-type operating in an enhancement mode. The saturation voltage derived from the I-V expression was found to decrease significantly, as compared to uniform channel having comparable semiconductor film thickness as the source end of the graded channel.