Showing papers on "Equivalent series resistance published in 1988"

Schottky barrier and pn-junction I/V plots — Small signal evaluation

Abstract: This paper proposes and examines three different plots for the determination of the saturation current, the ideality factor, and the series resistance of Schottky diodes and solar cells from the measurement of a single current (I)/voltage(V) curve. All three plots utilize the small signal conductance and avoid the traditional Norde plot completely. A test reveals that the series resistance and the barrier height of a test diode can be determined with an accuracy of better than 1%. Finally it is shown that a numerical agreement between measured and fittedI/V curves is generally insufficient to prove the physical validity of current transport models.

Method of manufacturing integrated circuit containing bipolar and complementary MOS transistors on a common substrate

Abstract: An integrated circuit containing bipolar and complementary MOS transistors wherein the emitter terminals of the bipolar transistors as well as the gate electrodes of the MOS transistors are composed of the same material, consisting of a metal silicide or of a double layer containing a metal silicide and a polysilicon layer. The emitter base terminals are arranged in self-adjusting fashion relative to one another and the collector is formed as a buried zone. The collector terminal is annularly disposed about the transistor. As a result of the alignment in dependent spacing between the emitter and the base contact, the base series resistance is kept low and a reduction of the space requirement is achieved. The doping of the bipolar emitter and of the n-channel source/drain occurs independently. The method for the manufacture of the integrated circuit employs an n-doped gate material of the MOS transistors as a diffusion source and as a terminal for the emitters of the bipolar transistors and does not require an additional photolithography step. Because of the annular, deep collector region, a reduction of the collector series resistance and an increased latch-up hardness are achieved. The integrated semiconductor circuit is employed in VLSI circuits having high switching speeds.

Specific contact resistivity of metal-semiconductor contacts-a new, accurate method linked to spreading resistance

Abstract: A method to determine the specific contact resistivity of metal-semiconductor contacts has been developed. It allows the separation of the total series resistance between two contacts into the contributing component resistances. The principle of the method is the subtraction of the semiconductor spreading resistance from the total two-contact resistance. This requires geometrically well-defined small contacts that are fabricated precisely by lithographic methods. Using this method, accurate values were obtained for the specific contract resistivity of an aluminium-1.5% silicon alloy to p-type silicon wafers having dopant densities from 5*10/sup 14/ to 2*10/sup 20/ cm/sup -3/. The specific contact resistivity values are lower than previously published values obtained using earlier methods in which parasitic and nonideal effects could not be quantified or eliminated. The lower values indicate that contact resistance has a less-limiting effect on the performance of integrated circuits than presently believed. >

High breakdown active device structure with low series resistance

Abstract: Series resistance in the low impurity portion of a high breakdown PN junction of a three or four layer device is reduced by providing an increased impurity region at the junction of the same conductivity type as the low impurity portion and having an impurity profile such that the increased impurity region is depleted under reverse biasing before critical field is reached therein. The three layer device include insulated gate field effect transistors and bipolar devices and the four layer device is an SCR.

Physical equivalent circuit model for planar Schottky varactor diode

Abstract: A physical equivalent circuit model for the planar GaAs Schottky varactor diode is presented. The model takes into account the distributed resistance and capacitance of the active layer, the sidewall capacitance, and the parasitic resistances and accurately accounts for the high series resistance observed near the pinch-off voltage. The dependence of the maximum series resistance on varactor size, frequency, and doping profile has been theoretically investigated, and the results agree well with experimental data. The proposed model can be easily used for optimization of planar Schottky varactor diodes with regard to broadband monolithic VCO constraints. >

Schottky diodes with high series resistance: a simple method of determining the barrier heights

Abstract: The forward I–V characteristic of a Schottky diode is strongly affected by the series resistance. At low barriers and high resistances it is difficult to determine the diode parameters. I–V measurements at extremly low voltages enable the barrier height to be derived. In the case of indium tin oxide or palladium on a-Si:H, consistent results were obtained.

The Series Resistance of Submicron MOSFETs and its Effect on their Characteristics

Abstract: A process-related design formula for the MOSFET series resistances is discussed, assuming a linear doping profile for graded junctions. The main process variable is the lateral doping gradient, whereas the LDD-dose has little effect. Calculated resistance values agree well with measured data, which have been extracted from the parameters of a new MOSFET circuit model. In the latter model the current and saturation voltage are expressed explicitly in terms of the series resistances.

Characterization of Schottky barrier diodes by means of modulation technique

Abstract: On the basis of the ac modulation technique a novel method is developed, which permits the extraction of the key parameters of Schottky diodes, i.e., the ideality factor, the barrier height, and the series resistance. These properties can be derived at any forward bias voltage from the current‐voltage characteristic and its first and second derivative. Limitations to the method arise mainly from the voltage dependence of the effective barrier height, as can be shown by a model calculation. Applicability and exactness are demonstrated by experimental investigations of Ti/n‐Si diodes with high series resistance, Yb/n‐Si junctions, and Ti contacts on n‐type InP, In0.73Ga0.27As0.64P0.36, and In0.53Ga0.47As.

Microwave frequency operation of the heterostructure hot-electron diode

Abstract: The generation of microwave frequencies by the heterostructure hot-electron diode (H/sup 2/ED) is discussed. At 77 K, self-oscillation has been produced over a broad frequency range from direct current to 10.5 GHz, limited by the parasitic series resistance and capacitance. Considerations of the bias polarity required to produce oscillations and of their high-frequency response support a model of switching from tunneling to thermionic emission. >

Paralleled transconductance ultralow‐noise preamplifier

Abstract: A simple NJFET preamplifier was constructed from commercial parts using parallel input devices in a cascode configuration The equivalent input noise resistance was 85 Ω (038 nV/(Hz)1/2) at 1 kHz, and 12 Ω (045 nV/(Hz)1/2) at 100 Hz, measured at room temperature, independent of the source resistance For 50‐Ω sources, a gain of 29 dB was achieved from 3 Hz to 13 MHz The input noise equivalent resistance is verified by measuring the thermal noise of low‐valued wire‐wound resistors Circuit utility is demonstrated by noise measurements performed on GaAs Ohmic contacts at room temperature, under various bias conditions Design considerations for using parallel input devices, the bias criteria for them, and possible design extensions are discussed

Resistive and photoconductive effects in spectral response measurements

Abstract: It is shown that AC spectral response measurements done under DC bias voltage and bias illumination can include nonnegligible modulation effects from the series resistance of the device under test. The modulation effects change both the shape and the magnitude of the spectral response curve as a function of bias voltage and bias illumination. It is shown how high-efficiency CuInSe/sub 2//CdS devices exhibit this kind of behavior and how to correct for it. By analyzing the spectral response of CuInSe/sub 2//CdS devices as a function of voltage bias, a value of the series resistance is extracted which agrees with that derived from I-V measurements. >

Deterioration diagnosis of electrolytic capacitor in a buck-boost converter

Abstract: A method is proposed for diagnosing the deterioration of an electrolytic capacitor with a finite life span used in the active circuit of a buck-boost converter. Such information is needed for preventive maintenance of DC-to-DC converters. The method is based on the fact that the equivalent series resistance (ESR) of the electrolytic capacitor increases as it deteriorates, which causes in turn an increased ripple in direct proportion to the ESR. >

Two-Dimensional Simulations of Current Flow in Amorphous Silicon Thin-Film Transistors

Abstract: Whereas one-dimensional models can adequately predict the current-voltage behavior of ideal thin-film transistors, a detailed study of current flow requires a comprehensive two-dimensional simulation. Such an analysis provides important information regarding effective series resistance, overlap capacitance, and currentcrowding near electrodes. Numerical simulations also allow the rapid development and optimization of new devices. We have developed a two-dimensional finite-element device simulator (MANIFEST) which we have used to study the effect of source-to-gate misalignments on the performance of amorphous-silicon TFTs. We find that submicron source-togate gaps do not seriously impair TFT performance.

Si 太陽電池의 表面再結合 電流가 飽和電流에 미치는 影響

Abstract: The effect of surface recombination current density on the saturation current density in Si solar cell has been studied. Theoretical model for surface recombination current was set up from emitter transparent model of M.A. Shibib, and saturation current of Si solar cell made by ion implantation method was also measured by digital electrometer. The theoretical surface recombination current density which is the same as saturation surface recombination current density in Shibib model was 10-¹¹ [A/㎠] and the measured value was ranged from 8 × 10^(-10) to 2 × 10^(-9) [A/㎠]. Comparing with the ideal p-n junction of Shockley, transparent emitter model shows improved result by 10² order of saturation current density. But there still exists 10² order of difference of saturation current density between theoretical and actual values, which are assumed to be caused by 1) leakage current through solar cell edge, 2) recombination of carriers in the depletion layer, 3) the series resistance effect and 4) the tunneling of carriers between states in the band gap.

Enhancement of current peak‐to‐valley ratio in In0.52Al0.48As/In0.53Ga0.47As ‐based resonant tunneling diodes

Abstract: The electrical characteristics of In052Al048As/In053 Ga 047 As resonant tunneling diodes are reported These devices exhibit current peak‐to‐valley ratios up to 67 at room temperature Differences in the current‐voltage characteristics for devices made from epilayers grown simultaneously on n+ and semi‐insulating InP substrates demonstrate the importance of minimizing the parasitic series resistance The enhanced peak‐to‐valley ratio has been attributed to thick In052Al048 As barriers (50 A) and wide, undoped In053Ga047 As spacer‐layers (400 A)

Quantum well tunnel triode

Abstract: We demonstrate a novel three‐terminal device, the tunnel triode, in which the current within the quantum well is a part of the tunnel current through the p+‐n+ junction. A tunnel‐diode‐like negative differential resistance effect with peak‐to‐valley ratio as high as 20 was observed, the tunnel current being controlled by the gate voltage. We show that tunneling occurs not in the quantum well, but in the heavily doped n+‐Al0.3Ga0.7As layer, and it is preceded by a real‐space hot‐electron transfer from the quantum well into this layer. Logic operation of a bistable switch was obtained in a circuit comprising a tunnel triode and a series resistance.

Series resistance effects in electrochemical carrier concentration profiling

Abstract: The authors present measurements of admittance over four decades of frequency for large-area liquid-electrolyte Schottky contacts to highly-doped semiconductor specimens. An analysis of this data is used to demonstrate that the electrolyte series resistance will give rise to errors in the measurement of electrochemical carrier concentration profiles for highly-doped semiconductors. This problem may be overcome by an alternative method of analysing the data.

Development, testing and performance of HV power capacitors

Abstract: Economic and environmental pressures have stimulated rapid changes in power-capacitor technology. Due to the development of stronger and easier-to-impregnate polypropylene films, together with the successful introduction of a dozen or more new nonPCB impregnating fluids, a new generation of low-loss high-capacitance all-film capacitors are gradually replacing the traditional all-paper and mixed paper-film types. The author discusses the development and improvements of power capacitors and then goes on to discuss the all-film capacitors. In-service performance of power capacitors, testing, and transient overvoltage testing are also discussed.< >

The effect of series resistance in electro-chemical carrier profiling

Abstract: The influence of a series resistance in electrochemical carrier concentration profiling of GaAs is discussed. It is demonstrated that an enhancement of the standard admittance data calculation is beneficial in extending the range of material doping conditions that can be usefully analysed and is especially applicable to certain p-type samples.

A high resonant frequency multilayer ceramic capacitor for use in SMPS applications

Abstract: Multilayer ceramic (MLC) capacitor designs which demonstrate high resonant frequency, exceptionally low effective series resistance, and high retention of effective capacitance up to resonance have been implemented and tested. These characteristics indicate that MLC capacitors can be used in small high switch frequency, modular power supplies. Properly designed and manufactured, MLC capacitors demonstrate megahertz resonant frequency, milliohm ESR, and good capacitance retention. >

Capacitor provided with fuse

Abstract: PURPOSE:To prevent the heat generation of a capacitor element, and reduce its inductance, by a method wherein a lead-wire provided with a fuse is used as one of a plurality of lead-wires, by connecting a fuse to a lead-wire led out from the capacitor element main body, in series with the capacitor element main body. CONSTITUTION:One of two cathode-lead-wires is used as a cathode-lead-wire 2 connected to the side surface of a capacitor element 5. Between the element 5 and a cathode-lead-wire 3 which is not in contact with the element 5, the other lead-wire is connected to a fuse 1 in series with the element 5. Thereby, the resistance component of the fuse 1 itself can be prevented from acting as an equivalent resistance of the capacitance. The inductance component of the fuse 1 itself is, from an equivalent circuit view-point, converted from a series residual inductance of the capacitor to the other function, and the by-pass effect in a high frequency region is improved. Thereby, the heat generation is prevented, and the inductance is reduced.

Selection and characteristics of non-linear capacitors with ferroelectric dielectrics as turn-off snubbers

Abstract: Losses in power electronic switches can be reduced by using nonlinear voltage-dependent capacitors as turn-off snubbers. It has been discovered that distinct voltage-dependent events occur in the dielectric of the capacitors when placed under voltage stress. The authors discuss the use of this phenomenon as a possible criterion for selecting capacitors from components mass-produced for the consumer market. The selected capacitors are then tested in situ in power electronic switches up to frequencies of 30 kHz, and it is found that the capacitors have thus far operated reliably as snubbers. >

Switched capacitor tape filter circuit

Abstract: PURPOSE:To contrive to decrease the circuit current by replacing a resistor into an equivalent resistance block formed by circuits of parallel connection each having two switches whose drive clocks are inverted to each other between the terminal and a ground terminal of a capacitor. CONSTITUTION:A three-stage of low pass filter, for example, consists of an operational amplifier 10 employing resistors RA, RB, an input capacitor C1, a feedback capacitor C2, an input stage capacitor C3, and the 1st - 3rd two- terminal circuit block 11 - 13. The 1st - 3rd two-terminal circuit blocks 11 - 13 are operated by switching 2 parallel capacitors CR1 - CR3 switched alternately by switches S1, S2. The 1st - 3rd blocks 11 - 13 are regarded as a prescribed value of resistance. Thus, the filter characteristic is decided by the capacitance ratio Li/CRi of the capacitors and the clock frequency fs. Moreover, a 2nd order LPF is obtained by eliminating the 3rd block 13 and the capacitor C3 from the configuration stated above.

Electronic wrist watch with power generator

Abstract: A rectifier circuit for an AC generator based upon the electromagnetic conversion and an overcharge-preventing circuit are combined together as shown in (Fig. 5A), in order to obtain, in a small number of diodes, the electric power generating performance equivalent to that of the diode bridge, thus making it possible to reduce both the size of the limiter Tr and the consumption of electric power by the circuit. A resistor is connected in series with a capacitor so that a booster circuit is started with a predetermined capacitor voltage. Using Tr for short-circuiting, furthermore, the Tr for short-circuiting is turned on under the boosting condition, whereby the series resistance component is cancelled to secure charging performance. Further, the booster circuit consists of a multiplicity of stages to enable the watch to be driven over a wide range of voltages. The boosting magnification is changed by detecting the voltages of auxiliary capacitors, thus making it possible to change the setpoint voltage and to expand the booster circuit. By adjusting the sampling timing for voltage detection at the moment the boosting operation is to be started and for voltage detection at the moment the boosting magnification is to be changed, furthermore, it becomes possible to start the booster circuit without fail.

Miniaturization limit of a cloth inductor

Abstract: A cloth‐structured magnetic device was designed, and the optimized relation between amorphous fiber and conductive fiber size was shown. The inductance, equivalent resistance, and quality factor of cloth‐structured magnetic devices were calculated. Furthermore, the stray capacitance of the device was estimated from the analysis of an equivalent circuit. A cloth inductor of only 0.7 mm thickness could be made, which could have an inductance of 100 μH, a rating current of 100 mA, and a quality factor over 60. Regarding the further miniaturization of the device, the magnetic flux distribution established inside the cloth inductor was measured. The miniaturization limit was estimated, which was influenced by the magnetic permeability and the aspect ratio of the fibers.

A New Method for Measurement of MOSFET Channel Length

Abstract: We use the transresistance r≡gm/g2 to measure channel length of MOSFET's with arbitrary parasitic source-drain series resistance. The channel length error due to the bias dependence of series resistance is completely eliminated by extrapolation to zero gate drive. The final accuracy is limited by sourcedrain asymmetry and errors in threshold voltage measurement; measurements on 0.5 µm lightly-doped drain MOSFET's indicate it is about 3 nm and a factor of seven better than previous methods.

GaInAs photodiodes as transfer standards for picosecond measurements

Abstract: GaInAs photodiodes are developed for use as pulsed transfer standards at the optical fibre communications wavelengths. The concept and requirements for a transfer standard photodiode are discussed. The photodiode and mount are theoretically modelled, results indicate that there is an optimum epitaxial layer thickness and diode series resistance for a particular device diameter and mount inductance. Measurements are made of an unoptimised 45 μm diameter device mounted on a prototype reverse terminated coplanar holder. A measured FWHM of 40 ps was obtained at 1146 nm, and the 3 dB frequency response is measured as 10.8 GHz at 1060 nm.

Millimeter-wave monolithic GaAs IMPATT VCO

Abstract: A monolithic voltage-controlled oscillator (VCO) is described that was constructed using a GaAs double-drift Read IMPATT diode as the active element and a similar diode biased below breakdown as the varactor. The chip produced 120-mW peak power over an electronically controlled tuning range between 47 to 48 GHz. A computer analysis based on characterized circuit parameters was used to predict the performance of the chip. The key limiting factor in the power and tuning is the presence of large parasitic series resistance in the varactor. By utilizing a single-drift doping profile, improved performance can be expected. >