The Experts below are selected from a list of 6378 Experts worldwide ranked by ideXlab platform

M. Rodder - One of the best experts on this subject based on the ideXlab platform.

  • Modeling of nonhyperbolic sine I-V characteristics in poly-Si resistors
    IEEE Electron Device Letters, 1992
    Co-Authors: M. Rodder
    Abstract:

    Poly-Si resistors with an unimplanted channel region (and with n-type source/Drain regions) can exhibit a nonhyperbolic sine (non-sinh) I-V characteristic at low V/sub DS/ and an activation energy which is not simply decreasing monotonically with increasing V/sub DS/. These phenomena are not explained by conventional poly-Si resistor models. To describe these characteristics, a self-consistent model which includes the effects of a reverse-biased diode at the Drain End is presented. Numerical simulation results show excellent agreement with experiment in regard to the shape of the I-V characteristic and of the effective activation energy as a function of V/sub DS/. >

  • Increased resistance in p-type poly-Si resistors by thermal anneal reduction interface charge
    IEEE Electron Device Letters, 1991
    Co-Authors: M. Rodder
    Abstract:

    The effect of thermal annealing on characteristics of p-type poly-Si thin-film resistors was investigated. A significant increase was observed as the source/Drain anneal temperature or anneal time was increased. The increased resistance is due to a reduction in current component arising from field-enhanced current via grain-boundary trap states at the Drain End of the resistor. The reduction is this field-enhanced current arises primarily from a reduction of positive charge density at the top and bottom oxide/poly-Si interfaces of the thin-film resistor (and thus a reduction in the magnitude of the Drain electric field) with increased annealing temperature and time. >

  • Effects of channel width and parasitic bipolar action on p-type poly-Si resistor characteristics
    IEEE Electron Device Letters, 1991
    Co-Authors: M. Rodder
    Abstract:

    The effects of channel width on I-V characteristics of thin-film p-type poly-Si resistors are discussed, in particular for the case in which the resistor current is mainly due to field-enhanced generation of carriers at the Drain End (as can be common at high Drain electric field). A significant decrease in current per unit width (microamperes per micrometer) is observed as the channel width is reduced from 3 to 0.6 mu m. This decrease in current per unit width is due to the influence of fixed positive charge along the channel edges, which decreases the beta value associated with parasitic bipolar action in this regime of device operation. >

Ed Gerstner - One of the best experts on this subject based on the ideXlab platform.

  • source gated transistors in hydrogenated amorphous silicon
    Solid-state Electronics, 2004
    Co-Authors: J.m. Shannon, Ed Gerstner
    Abstract:

    Abstract Source-gated transistors form a new class of transistors in which the current is controlled entirely by the source. As such, they have properties that are fundamentally different from their nearest relative the field-effect transistor. Instead of using the field-effect to modulate the conductance of a channel it is used to change to electric field at a reverse biased source barrier thereby changing the source current. Saturation of the current occurs when the source is depleted of carriers by the reverse biased barrier. This feature contrasts markedly with saturation in a standard field-effect transistor that occurs when the Drain End of the channel is depleted of charge. A model describing the characteristics of a source-gated transistor is outlined and compared with characteristics measured on transistors made using hydrogenated amorphous silicon. Good agreement is found between theory and experiment. It is shown that the saturation voltage of the SGT can be very much smaller than it is in a FET leading to lower voltage operation and power dissipation. Furthermore, the output impedance of the SGT can exceed that of an FET. Transistors covering a wide range of currents have been made by modifying a Schottky barrier source using ion implantation.

  • Source-gated thin-film transistors
    IEEE Electron Device Letters, 2003
    Co-Authors: J.m. Shannon, Ed Gerstner
    Abstract:

    The thin-film transistor is one of a family of field-effect transistors. They all operate in the same way: a gate modulates the conductance of a channel and the current saturates when the Drain End is depleted of carriers. The authors introduce a source-gated transistor that overcomes some of the fundamental limitations of the field-effect transistor. The gate controls the supply of carriers and the current saturates when the source is depleted of carriers. The result is a thin-film transistor that can operate at lower voltages with larger gains and lower power dissipation. It should also preserve its characteristics with smaller dimensions.

M. Valdinoci - One of the best experts on this subject based on the ideXlab platform.

  • floating body effects in polysilicon thin film transistors
    IEEE Transactions on Electron Devices, 1997
    Co-Authors: M. Valdinoci, Guglielmo Fortunato, L. Colalongo, G Baccarani, Alessandro Pecora, I Policicchio
    Abstract:

    Floating body effects in polycrystalline silicon thin film transistors (poly-TFTs) are investigated by means of numerical simulations. The current increase in the output characteristics at large V/sub DS/, usually referred to as the "kink effect" is explained by impact ionization occurring in the high-field region at the Drain End of the channel. Its effect is enhanced by the action of a parasitic bipolar transistor in the back-channel region, whose base current arises from the impact generated holes. The depEndence of the kink on the recombination kinetics is also investigated.

  • High-electric-field phenomena in polycrystalline silicon thin film transistors
    Active Matrix Liquid Crystal Displays Technology and Applications, 1997
    Co-Authors: Guglielmo Fortunato, R. Carluccio, L. Colalongo, S. Giovannini, Luigi Mariucci, F. Massussi, M. Valdinoci
    Abstract:

    Polysilicon thin-film transistors are of great interest for their application in large area microelectronics and especially for their circuit applications. A successful circuit design requires a proper understanding of the electrical characteristics and in the present work some specific aspects related to the presence of high electric fields at the Drain End of the channel are presented.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

I Policicchio - One of the best experts on this subject based on the ideXlab platform.

  • floating body effects in polysilicon thin film transistors
    IEEE Transactions on Electron Devices, 1997
    Co-Authors: M. Valdinoci, Guglielmo Fortunato, L. Colalongo, G Baccarani, Alessandro Pecora, I Policicchio
    Abstract:

    Floating body effects in polycrystalline silicon thin film transistors (poly-TFTs) are investigated by means of numerical simulations. The current increase in the output characteristics at large V/sub DS/, usually referred to as the "kink effect" is explained by impact ionization occurring in the high-field region at the Drain End of the channel. Its effect is enhanced by the action of a parasitic bipolar transistor in the back-channel region, whose base current arises from the impact generated holes. The depEndence of the kink on the recombination kinetics is also investigated.

N. A. Economou - One of the best experts on this subject based on the ideXlab platform.

  • Leakage current of undoped LPCVD polycrystalline silicon thin-film transistors
    IEEE Transactions on Electron Devices, 1995
    Co-Authors: Charalabos A. Dimitriadis, P. A. Coxon, N. A. Economou
    Abstract:

    The leakage current of thin-film transistors on undoped polycrystalline silicon layers, deposited by low-pressure chemical vapor deposition, is investigated in relation to the deposition pressure. For films deposited at pressure 40 mTorr, the leakage current I/sub L/ is controlled by the intrinsic resistivity of the film. The increase of the current I/sub L/ with increasing gate and Drain bias voltages is due to the Joule-induced-heating effect. For films deposited at pressures below 40 mTorr, the leakage current is controlled by the reverse-biased junction at the Drain End. In this case, the minimum leakage current is modeled as thermal generation current arising from midgap Coulombic defect trap states. When the gate and Drain bias voltages are increased, the thermally generated current is enhanced by the Poole-Frenkel effect due to high electric fields at the Drain junction. Such high electric fields at the Drain End can arise from doping inhomogeneities because of fast diffusion through the grain boundaries of the implanted Drain dopant. At high bias voltages, a deviation from linearity of the Poole-Frenkel current-voltage characteristics is observed due to the hot carrier effect. >