Generalized theory and realization of a voltage-controlled negative resistance MOS device (lambda MOSFET)

A generalized theoretical approach used to predict circuits which exhibit the three-terminal negative resistance MOS characteristic is presented. The main structure of the positive feedback circuit is accomplished by connecting the drain and gate terminals of an n-channel enhancement mode MOSFET with the input and output terminals of an inverter circuit. The characteristic parameters such as the peak current, the peak voltage, the negative resistance, and the valley voltage are derived in a generalized form. Based on the theoretical predictions, several high density integrated circuits that give rise to a voltage-controlled negative resistance characteristic were fabricated and are described.     

An accurate voltage-controlled negative resistance circuit

A novel voltage-controlled negative resistance circuit incorporating n-p-n current mirrors is presented. Fully compatible with silicon IC technology, the circuit provides linear negative resistance characteristics that can be set precisely with external resistors. Experimental results are presented for the basic circuit as well as some of its variants.     

A new photo-sensitive voltage-controlled differential negative resistance device—The lambda bipolar photo-transistor

A new photo-sensitive voltage-controlled differential negative resistance device called the LAMBDA bipolar photo-transistor is presented. The basic structure of the Lambda bipolar photo-transistor consists of the simultaneous integration of a bipolar junction transistor and a merged metal-oxide-semiconductor field effect transistor. The IV characteristic of this new device will exhibit a voltage-controlled differential negative resistance when the device is exposed to light. The operational principle of this new device will be described and the characteristics of the fabricated device are discussed.     

A new high-power voltage-controlled differential negative resistance device—The lambda bipolar power transistor

A new high power voltage-controlled differential negative resistance device using the LAMBDA bipolar transistor structure, called the LAMBDA bipolar power transistor, is proposed and studied. The basic structure of this new device consists of the simultaneous integration of an interdigitated bipolar junction transistor and a merged metal-oxide-semiconductor field effect transistor. Two basic interconnection configurations of the integrated devices are also discussed. Several interesting applications based on the fabricated devices are also demonstrated. It is shown that the proposed device can be used as power signal generator and amplitude modulator using very simple circuits.     

A sinusoidal voltage-controlled oscillator for integrated circuits

This article describes an inductorless near-harmonic voltage-controlled oscillator circuit that utilizes a compensated Wien-bridge topology with a voltage-controlled Miller integrator as the tuning element. Suitable for monolithic integrated realization, the VCO offers a two-to-one control range for frequencies up to 10 MHz, with less than a 1-dB amplitude variation and less than a ten percent total harmonic distortion over the entire control range.     

A new Λ-type negative resistance device of integrated complementary FET structure

A new type of negative resistance diode having a Λ-type I-V characteristic is presented. The device is constructed by a functional integration of two complementary FET's of an n- and p-channel depletion mode. The operational principle together with some experimental results are described.     

A new negative resistance oscillator model

A physically justifiable mathematical model is proposed for a class of current-controlled, negative resistance oscillators having terminal characteristics which are poorly represented by the van der Pol, Scott, and Ceschia-Zecchin equations. Such resonators are typified by the monolithic emitter-coupled astable multivibrator (ECAM). A unique, three-parameter equation, based on the inverse hyperbolic tangent, is matched to the ECAM voltage-current curve. Using the method of Kryloff and Bogoliuboff, the transient and steady-state behavior of the ECAM is derived for oscillation with single-mode and double-mode LCR networks under quasi-linear conditions. An expression for the time of amplitude build-up and decay is derived. A phase plane is constructed for the double-mode case, yielding a system apparently free of simultaneous modes. The validity of the model is experimentally verified for quartz-controlled ECAM devices. The analysis results are extendable ton resonant modes and may be generalized to voltage-controlled devices.     

A new negative resistance of semiconductor bulk

An analysis is presented of a new negative resistance that appears when the drift velocity of carriers exceeds the thermal velocity in the ordinary element semiconductor bulk. The theory may offer one explanation for a new current instability recently discovered [1].     

A new long-channel MOSFET model

A new highly accurate long-channel MOSFET model which is valid both in the linear and saturation regions by taking into account two-dimensional effects over the whole channel is presented in this paper. The calculated results are in excellent agreement with the experimental data. Compared with three other long-channel MOSFET models, the double integral model, the charge-sheet model and the single-integral model, our model has some advantages. The results demonstrate that two-dimensional effects are important in the current continuity near the drain end of the channel and cannot be neglected when the MOSFET is operating in saturation.     

A low drift fully integrated MOSFET operational amplifier

A fully integrated MOSFET amplifier with very low drift has been built using standard technology. Input offset voltages as low as 5 /spl mu/V and drift values of this offset voltage less than 0.05 /spl mu/V//spl deg/C are measured.     

Noise associated with distributed resistance of MOSFET gate structures in integrated circuits

The effect of thermal voltage fluctuations in a resistive gate matrix perpendicular to the direction of channel current, in a MOSFET, are treated in detail. A general formula is derived to arrive at channel current fluctuations for an arbitrary gate matrix layout. This formulation is an extension of the analysis done by Thornber and is valid for frequencies at which the distributed RC time constants associated with the gate matrix are not important. The results of this analysis can be used to design low-noise resistive gate structures.     

Planar GaAs MOSFET integrated logic

Selective and multiple ion implantations directly into a semi-insulating GaAs substrate were utilized to fabricate planar integrated circuits with deep-depletion plasma-grown native oxide gate GaAs MOSFET's. 1.2-µm gate 27-stage enhancement/depletion (E/D) type ring oscillators, with the circuit optimized to reduce parasitic capacitance, were fabricated (using conventional photolithography) to assess the speed-power performance in digital applications. A minimum propagation delay of 72 ps with a power-delay product of 139 fJ was obtained, making these devices the fastest among current GaAs and Si logic fabricated by conventional photolithography. A minimum power-delay product of 36 fJ with a propagation delay of 157 ps was obtained. The power-delay product is comparable with that of 1.2-µm gate GaAs E-MESFET logic, and the speed is more than twice as great. This paper includes a comparison of the theoretical cut off frequency of MESFET and MOSFET logic devices operating in depletion mode. Results indicate that MOSFET logic has superior potential for high-speed operation.     

Chip-package codesign of integrated voltage-controlled oscillator in LCP substrate

This paper presents the design and characterization of a negative resistance type 1.9-GHz oscillator using high quality factor (Q) embedded lumped-element LC passives in an organic-based substrate with liquid crystalline polymer (LCP) dielectric material. A design strategy using analytical models is implemented to determine the value of the base inductance subject to the constraints set by power dissipation. Additionally, the effect of component Qs on the phase noise is qualitatively discussed. This paper also addresses the effects of the parasitics of the surface-mount active devices on the noise spectrum of a negative resistance type voltage-controlled oscillator (VCO). The designed VCO is fully embedded in the LCP substrate and uses high Q on-package passive components. The VCO was measured to operate at 1.92 GHz dissipating 14 mW of dc power and measured a phase noise of -118dBc/Hz and -133 dBc/Hz at 600 KHz and 3-MHz offset, respectively. The high Q of the LC tank circuit was utilized to optimize the VCO to operate from a 2-V supply at bias current of 0.9 mA. Finally, the design and implementation issues in a 2.25-GHz Colpitt's oscillator on LCP substrate are shown. The effects of scaling capacitance ratio on VCO phase noise and on power consumption are verified for the Colpitt's oscillator.     

A new edge-defined approach for submicrometer MOSFET fabrication

A novel technique employing vertical (anisotropic) dry etching for fabricating edge-defined submicrometer MOSFETs is described, and preliminary results are presented. Three basic process techniques are employed: formation of an edge-defined submicrometer element, pattern transfer of the element into an underlying doped polysilicon gate layer, and passivation of the FET using a sidewall oxide. The submicrometer element formation technique is limited to linewidths in the 0.1 µm to 0.4 µm range. Characterization of MOSFETs, having physical channel lengths ∼0.1 µm to 0.15 µm and believed to be the world's smallest MOSFET's reported to date, is discussed.     

A new method to determine MOSFET channel length

A new method is proposed to electrically determine MOS transistor channel length with both accuracy and convenience. Based on the linear region relationship between effective channel length Leffand channel resistance Rchanof an MOS transistor, this method determines Leffby applying relatively large but constant gate voltage to eliminate threshold voltage determination and takes into account external resistance. Comparison of this method with SEM measurement shows very good agreement (within ±0.1 µm resolution limit of our SEM technique).     

一种新型的负型激光光致抗蚀剂

用氮分子激光诱导聚甲基丙烯酸甲酯(PMMA)与4,4′-二迭氮二苯基砜(4,4′-DDS)的交联聚合反应,使PMMA由正型转变为负型抗蚀剂。用付立叶变换红外光谱法研究其反应动力学,研究了交联剂4,4′-DDS、敏化剂4-笨氧基二笨甲酮以及防氧剂对一二甲胺苯甲醛对于反应速率、量子产率、转化率以及反应诱导期的影响。     

A bipolar voltage-controlled tunable filter

A complete monolithic state variable filter is described which has been fabricated with bipolar technology. Two-quadrant multipliers are used in a novel fashion to achieve integration time constant large enough for audio purposes. Voltage control of frequency response from 20 Hz to above 20 kHz has been achieved without sacrifice of accuracy (notch depth >50 dB, low-pass and bandpass responses accurate to better than 0.1 dB), dynamic range (>90 dB), power supply rejection (PSRR>40 dB) or frequency drift (<200 ppm//spl deg/C). The design has been shown to be generally useful in the design of self-contained bipolar filters.     

Current divider: a new negative feedback element for integrated amplifiers

A multistage small-signal amplifier is described having, instead of resistors, a current divider in the negative-feedback pad. The current divider is a transistor which has two collectors with very different current gains. In spite of not using any passive components, linear and stable amplification has been achieved, down to input currents of 10?11 A.     

MOSFET thermal noise modeling for analog integrated circuits

The effects of device geometry, oxide thickness, and bias condition on the thermal noise of MOSFET's are investigated. The experimental results show that the conventional MOSFET thermal noise models do not accurately predict the thermal noise of MOSFET's. A model that is capable of predicting the thermal noise of both long and short channel devices in both the triode and saturation regions is presented. This model, which can be easily implemented into existing circuit simulators such as SPICE, has been verified by a wide variety of measurements     

A lambda-type current-controlled negative resistance device

A new structure is presented for the implementation of a λ-type current-controlled negative resistance device in conventional bipolar technology. Expressions for the characteristic parameters, such as: the holding current, the peak current, and the peak voltage, are given.