Showing papers by "Chenming Hu published in 1979"
01 Jan 1979
TL;DR: In this paper, a closed-form expression for the gate current has successfully reproduced the dependence on V g,V d and L. The lucky electron model suggests that the channel hot electron effect would be negligible if V d -V s is less than 2.5 volt no matter how small the channel length or junction depth.
Abstract: The lucky electron model proposes that an electron is emitted into SiO 2 by first gaining enough energy without suffering an energy stripping collision in the channel and then being redirected toward the Si/SiO 2 interfact. A closed-form expression for the gate current has successfully reproduced the dependence on V g ,V d and L. This model also suggests a straightforward correlation with the substrate current. By measuring the substrate current one may be able to replace or supplement long-term stress test for studying a component of channel hot electron emission that causes instability but does not show up in the gate current. The lucky electron model suggests that the channel hot electron effect would be negligible if V d -V s is less than 2.5 volt no matter how small the channel length or junction depth.
122 citations
TL;DR: In this article, the authors derived the optimum doping profile of a lightly doped layer that introduces the minimum series resistance and sustains a given junction breakdown voltage, which applies to a one-dimensional Schottky diode and qualitatively to the collector or drain doping profiles of transistors.
Abstract: The optimum doping profile of a lightly doped layer that introduces the minimum series resistance and sustains a given junction breakdown voltage is derived. The theory applies to a one-dimensional Schottky diode and qualitatively to the collector or drain doping profiles of transistors. The minimum series resistance is found to be about 3.7 × 10-9 V\min{B}\max{2.6} Ω.cm2for an n silicon layer. The optimum doping profile can be closely approximated by a conventional uniformly doped n-n+structure.
118 citations
18 Jun 1979
TL;DR: In this paper, the theoretical limitations of V-grooved and double-diffused power MOSFETs are studied using several design parameters as variables, and a new structure is proposed that could raise the power capability by an order of magnitude in very high voltage devices.
Abstract: The theoretical limitations of V-grooved and double-diffused power MOSFETs are studied using several design parameters as variables. The results are used to gauge the performance of currently available power MOSFETs and to project the capabilities of future devices. With proper design, the channel resistance can be negligible so that the on-state resistance is that of the bulk material (~8.3xl0-9 VdsB 2.5 Ω.cm2) plus the lead resistance. A transmission line effect associated with long resistive gate electrodes could limit the speed of certain devices. Devices with the capability of switching 10 kW per cm2 of chip area and hundred kilowatt per package are theoretically possible over a very wide voltage range. A new structure is proposed that could raise the power capability by an order of magnitude in very high voltage devices.
79 citations
TL;DR: In this article, carrier recombination in heavily doped semiconductors via shallow donor or acceptor states is analyzed and the results are in general agreement with experimental lifetime observations including the 1/n20 or 1/P20 dependence, and the insensitivity to temperature and to the dopant used.
Abstract: Carrier recombination in heavily doped semiconductors via shallow donor or acceptor states is analyzed. The results are in general agreement with experimental lifetime observations including the 1/n20 or 1/P20 dependence, and the insensitivity to temperature and to the dopant used. Capture cross sections of about 10−20 cm2 needed to fit the lifetime data are reasonable for neutral traps and are consistent with low‐temperature capture cross sections reported for shallow dopants.
16 citations
TL;DR: In this paper, a new technique determined the J•E characteristics of silicon dioxide grown from polycrystalline silicon with greatly improved sensitivity and the current density was measured over a 10−decade range without the problem of current drift or uncertainty about the field at the cathode surface due to charge trapping in the oxide.
Abstract: A new technique determined the J‐E characteristics of silicon dioxide grown from polycrystalline silicon with greatly improved sensitivity. More importantly, the current density was measured over a 10‐decade range without the problem of current drift or uncertainty about the field at the cathode surface due to charge trapping in the oxide. The apparent barrier height decreased with increasing electric field as if the barrier lowering was due to field enhancement at surface asperities of about 500 A in size. The technique is applicable to other dielectrics where charge trapping presents difficulties to J‐E measurements.
11 citations
01 Jan 1979
TL;DR: In this article, a method of characterizing the N-σ (density -capture-cross-section) distribution of electron traps in insulators is presented, which is consistent with this density-crosssection distribution, first order rate dynamics of trapping, and unnoticeable new trap generation by field or current stressing under the test conditions.
Abstract: This paper presents a method of characterizing the N-σ (density -- "capture-cross-section") distribution of electron traps in insulators. Requiring only voltage-time measurements made at constant currents, this method has found for oxides grown from poly-Si N ∝ σ-1.16. The previously reported absence of saturation in electron trapping in these oxides is explained by the high density of traps with small cross-sections. The trap density and cross-section are insensitive to the oxidation condition. The observed trapping characteristics is consistent with this density-cross-section distribution, first order rate dynamics of trapping, and unnoticeable new trap generation by field or current stressing under the test conditions.
3 citations