Tunneling Diode Pair Research Articles

Area-Efficient Series-Connected Resonant Tunneling Diode Pair as Binary Neuron in Cellular Neural Network

In this letter, we propose an area-efficient series-connected resonant tunneling diode pair device (SCRTD) to utilize as a binary neuron device in cellular neural networks (CNNs). The proposed SCRTD (P-SCRTD) consists of two RTDs interconnected by a floating metal layer with a high-doped epitaxial layer. The P-SCRTD shows a 48 % reduction in area by eliminating the isolation area in the conventional SCRTD (C-SCRTD) owing to the symmetrical I-V characteristic of the RTD, without any performance penalty on the DC and RF characteristics by means of adopting the floating metal layer, compared to the C-SCRTD. CNN application of the P-SCRTD is investigated, showing inherent threshold operation and high-speed (12.5 Gbps) low-power (21 mW) performance, despite using the $2~\mu \text{m}$ technology node, for a unit cell for edge extraction.

A 24-GHz Low-Power RTD-Based ON–OFF Keying Oscillator With an RTD Pair Configuration

In this letter, an ON–OFF keying (OOK) oscillator that uses a resonant tunneling diode (RTD) pair configuration has been designed and fabricated. To achieve improved RF output power characteristics, the RTD pair topology was utilized in the RTD OOK oscillator design to realize an increased negative differential conductance voltage span. The fabricated IC showed high-speed switching capability of 5 Gb/s with a good phase noise characteristic of −118.17 dBc/Hz at a 1-MHz offset. The maximum RF output power was determined to be −1.76 dBm at a carrier frequency of 24.1 GHz. It consumes 12.5 mW of power, resulting in a good figure of merit value of 2.5 pJ/bit. These results demonstrate its potential as a high-performance ON–OFF mode oscillator for high-data-rate OOK transceiver systems.

Bistable-Body Tunnel SRAM

A one-transistor tunnel static random access memory (SRAM) cell is proposed and analyzed. The new cell uses the bistability of a tunnel diode pair to latch the body voltage of a MOSFET that then shifts the threshold voltage and enables sensing of the state by the measurement of the MOSFET transistor current. Band-to-band tunneling is used to write the cell. This cell offers more than 10 000× reduction in static power compared to the 6-transistor (T) SRAM at the 32-nm technology node. A cell size of 48F2 is shown, which is comparable to a 6-T SRAM. Access times should be similar to high performance a 6-T SRAM given the same transistor technology.

A Third Order Harmonic Oscillator Based on Coupled Resonant Tunneling Diode Pair Oscillators

A third order harmonic oscillator has been proposed based on the resonant tunneling diode pair oscillators. This oscillator has significant advantages, good stability of the oscillation frequency against the load impedance change together with capability to output higher frequencies. Proper circuit operation has been demonstrated using circuit simulations. It has been also shown that the output frequency is stable against the load impedance change.

Improved Bias Stability of the Resonant Tunneling Diode Pair Oscillators Integrated on an AlN Ceramic Substrate

Resonant tunneling diode (RTD) pair oscillators were fabricated on an AlN ceramic substrate employing a novel integration process based on an assembly of small device blocks. By using this process, chip capacitors were mounted close to the oscillator without large parasitic inductance. This can relax the severe condition for bias stability. Stable oscillations were observed in the fabricated circuits at 35–50 GHz. A good single sideband phase noise of -100 dBc/Hz at a 100 kHz offset frequency was also observed for the fabricated circuit.

High-Power Oscillations in Resonant Tunneling Diode Pair Oscillator ICs Fabricated with Metamorphic devices

A high power operation was demonstrated for novel resonant tunneling diode (RTD) oscillator circuits fabricated with metamorphic RTDs. The circuits consisted of series-connected RTDs with a shorted coplanar waveguide resonator. The bias instability problem of conventional RTD oscillators was solved by separating bias nodes from the oscillating node. This made it possible to use a large RTD area of 10 µm2 and to supply a large power of about 400 µW to a 50 Ω resistive load at 23 GHz.

Tri-State Logic Using Vertically Integrated Si–SiGe Resonant Interband Tunneling Diodes With Double NDR

A vertically integrated npnp Si-based resonant interband tunneling diode (RITD) pair is realized with low-temperature molecular beam epitaxy by stacking two RITDs with a connecting backward diode between them. The current-voltage characteristics of the vertically integrated RITD pair demonstrates two sequential negative differential resistance regions in the forward-biasing condition. Tri-state logic is demonstrated by using the vertically integrated RITDs as the drive and an off-chip resistor as the load.

Improved vertically stacked Si∕SiGe resonant interband tunnel diode pair with small peak voltage shift and unequal peak currents

A vertically integrated and serially connected npnp Si-based resonant interband tunnelling diode (RITD) pair is realised with low temperature molecular beam epitaxy (MBE) by monolithically stacking two RITDs with different spacer thicknesses. The asymmetric design manifests as unequal peak current densities that provide for much larger and uniform separation of the holding states for multi-valued logic. A δ-doped backwards diode connects the two serially connected RITDs with a very small series resistance. The I-V characteristic of the improved vertically integrated RITDs demonstrates two negative differential resistance (NDR) regions in the forward biasing condition with a small peak shift and unequal peak currents.

Multivalued SRAM cell using resonant tunneling diodes

A multivalued SRAM cell using a vertically integrated multipeak resonant tunneling diode (RTD) pair is described. Two RTDs in series can have 2N+1 stable states. With this concept, a five-stable-state memory cell has been implemented with two 2-peak RTDs. Several designs are presented for a high-speed static random access multivalued memory using the folding characteristics of RTDs. The different designs are described and studied by comparing their power consumption under different conditions of device parameters and switching speed. The authors show that the proposed memory cell using a pair of multipeak RTDs yields the best result from the standpoint of size, power dissipation, and speed among the RTD memory cells discussed. >

A new mode of operation-a controlled monostable tunnel-diode circuit

A new mode of operation of a tunnel-diode pair circuit has been developed and theory and circuit design are presented. Operation principles are discussed for damped-oscillation mode, unbalanced mode, and balanced mode with overdamping. Since the circuit has a high degree of freedom, several applications are possible, for example, as an inverter, pulse shaper, quasi-stable memory, and time-to-pulse width converter. The test circuit arrangement together with some experimental results are reported and characteristics of the different modes are discussed.

Computer aided analysis of the controlled monostable tunnel diode circuit

A controlled monostable tunnel diode pair circuit, which combines monostable with bistable action, has been simulated with the NET-1 computer program, using a tunnel diode model developed for NET-1. The basic circuit, its composite dc characteristics, and simulated and experimental output pulses are presented. Simulation and experiments show good agreement.

Design of ACP Tunnel-Diode-Coupled Circuits

The performance of the Advanced Circuit Program (ACP) circuits described by D. H. Chung and J. A. Palmieri can be improved by replacing the coupling resistor with a pair of tunnel diodes. The low impedance and power gain properties of the tunnel diode increase the fan-power and provide better control of signal levels. In addition, the improved rise times increase circuit speeds to the extent that delays of less than 1 nsec per logic function have been demonstrated. Since the tunnel diode pair can be designed to perform AND, OR, or majority logic functions, the logic flexibility of these circuits is greater than that of the resistor-coupled circuits. The design techniques which lead to a consistent set of logic circuits and to binary full adders are discussed. The very fast rise times generated by the tunnel diode pair require the use of transmission lines as the interconnection medium. The techniques used to minimize the effects of noise and reflections on circuit performance are discussed.

Video Transmission by Delta Modulation Using Tunnel Diodes

A method is described which enables video signals to be transmitted by the pulse code modulation system known as delta-modulation. A tunnel-diode balanced pair (Goto pair) is used for converting the video signal into a binary signal. With a new and very simple circuit, operating at a bit rate of 100 Mc, a ratio of signal-to-quantizing noise of 42 db is obtained. A more conventional circuit, that combines tunnel-diodes with transistors, makes an even lower quantizing noise possible.

High-Speed Analog-to-Digital Converters Utilizing Tunnel Diodes

Two analog-to-digital sequential converters have been devised which combine in one tunnel-diode pair per bit the functions of an amplitude discriminator and memory. In addition, one of the two schemes utilizes each tunnel-diode pair as a delay network. The conversion duration of one of these six-bit converters, which employs germanium 2N559 transistors and gallium arsenide 1N651 tunnel diodes, has been set to 1 μsec. Shorter conversion times are possible, but are not required in the present application of that converter as an integral part of an electronic high-speed signal processing system. The use of tunnel diodes presents a significant improvement in the art of converter design by virtue of circuit simplicity and performance. The paper describes the principle and operation of the converters and discusses pertinent considerations for their design. Particular emphasis is given to the discriminator property of a series-aiding tunnel-diode pair. A comprehensive bibliography relating to tunnel-diode switching circuits is attached.