Yongsik Jeong

A Novel High-Speed Multiplexing IC Based on Resonant Tunneling Diodes

A new multiplexing IC based on the resonant tunneling diode (RTD) is proposed. The unique negative differential resistance characteristics arising from quantum effects of the RTD enable us to develop a new functional low-power digital circuit. The proposed multiplexing IC consists of two current-mode-logic monostable-bistable transition logic elements (CML-MOBILEs) based on the RTD and a low-power selector circuit block. The proposed circuit has been fabricated by using an InP RTD/ heterojunction bipolar transistor monolithic microwave integrated circuit technology. The multiplexing operation of the fabricated quantum effect IC has been confirmed up to 45 Gb/s for the first time as a monolithic technology based on the quantum effect devices. The dc power consumption is only 23 mW, which is found to be one-fourth of the current state-of-the-art conventional transistor-based multiplexing IC.

Low DC-power ku-band differential VCO based on an RTD/HBT MMIC technology

This letter presents the design and fabrication of a Ku-band differential-mode voltage-controlled oscillator (VCO) with extremely low power consumption and good phase noise characteristics based on a monolithic InP-based resonant tunneling diode/heterojunction bipolar transistor (RTD)/(HBT) technology. In order to reduce the power consumption, an InP-based RTD is used for microwave power generation, which shows the negative resistance characteristics at a low voltage. The fabricated VCO shows an extremely low dc power consumption of 1.42mW and fairly good phase noise performance of -112 dBc/Hz at 1-MHz frequency offset. The figure-of-merit (FOM), which is used for comparing the performance of the fabricated oscillator with the previously reported results, was obtained to be -195 dBc/Hz. The obtained FOM is one of the best values among Ku-band differential VCOs reported so far.

Performance Improvement of InP-based Differential HBT VCO using the Resonant Tunneling Diode

A new InP-based RTD/HBT VCO, which has two RTDs at the nodes of resonators to increase the total negative gm in the conventional HBT VCO circuit, has been proposed for the first time. The output power and phase noise of the proposed VCO have been found to be enhanced by 3.3 dBm and 8.7 dBc/Hz, respectively, compared to the conventional one.

A Sub-100

This letter presents the microwave performance of a sub-100 ¿W Ku-band differential-mode resonant tunneling diode (RTD)-based voltage controlled oscillator (VCO) with an extremely low power consumption of 87 ¿W using an InP-based RTD/HBT MMIC technology. In order to achieve the extremely low-power Ku-band RTD VCO, the device size of RTD is scaled down to 0.6 × 0.6 ¿m2. The obtained dc power consumption of 87 ¿W is found to be only 1/18 of the conventional-type MMIC VCOs reported in the Ku-band. The fabricated RTD VCO has a phase noise of -100.3 dBc/Hz at 1 MHz offset frequency and a tuning range of 140 MHz with the figure-of-merit (FOM) of -194.3 dBc/Hz.

\mu{\rm W}

A new resonant tunneling diode (RTD) microwave oscillator operating at extremely low dc-power consumption is proposed, which utilizes the antiphase-coupled quantum-effect RTD oscillations for efficient ac-power generation at a summing node of output based on a push-push principle. The fabricated integrated circuit of the RTD microwave oscillator by using an InP-based RTD/HBT quantum-effect IC technology shows an extremely low total dc-power consumption of 85 ¿W at an oscillation frequency of 29.1 GHz. In order to achieve the extremely low dc-power consumption, the device size of RTD has been scaled down to 0.7 × 0.7 ¿m2. The obtained total dc-power consumption of 85 ¿W at an applied bias of 0.49 V is found to be the lowest reported up to date, corresponding to about 1/170 of that in the conventional-type low-power oscillators in the related frequency range.

Ku-Band RTD VCO for Extremely Low Power Applications

This paper presents the performance characteristics of 14 GHz InP-based RTD MMIC voltage-controlled oscillators with the extremely low DC power consumption. In order to further reduce the DC power consumption of RTD based VCOs, RTDs with a small emitter size, such as 1.5 times 1 mum2 and 1 times 1 mum2 , are used for the negative resistance generator of the VCOs. Each VCO is implemented by using the same resonator and output buffer except the RTD size to investigate the performance of the VCOs with the variation of RTD size. The fabricated VCOs showed the sub-mW DC power consumption which is suitable for wireless sensor applications

Novel Antiphase-Coupled RTD Microwave Oscillator Operating at Extremely Low DC-Power Consumption

A new lateral reverse-etching technique, developed for the InP DHBTs with emitters aligned to the [011~] direction which is well known to be more reliable than the other directions, is proposed and demonstrated. Two highly doped InGaAs and InP layers are utilized to alleviate the difficulty of lateral etching due to very little lateral etch rate along this direction. The DHBT with a 1.5/spl times/10 /spl mu/m/sup 2/ emitter size fabricated using this new method shows greatly improved peak f/sub max/ of 172 GHz and peak f/sub T/ of 120 GHz. From comparisons of microwave performance of the two devices which are fabricated with and without the new method, a 41% increase of f/sub max/ and a 45% reduction of base-collector junction capacitance have been achieved. Therefore, it has been verified that the proposed new method is very effective to considerably improve f/sub max/ by reducing the base-collector junction capacitance.

14 GHz InP-based RTD MMIC VCOs with Ultra Low DC Power Consumption

A Low DC-Power Multiplexer IC using an InP-based CML (current mode logic) -MOBILE (Monostable bistable transition logic element) RTD/HBT Technology has been proposed and fabricated. The proposed multiplexer topology is composed of two differential CML-MOBILE ICs and a newly proposed RZ-to-NRZ selector IC. By using the NDR (negative differential resistance) - based new topology, the DC power consumption has been significantly reduced compared to the conventional topology. The operation speed of the IC is confirmed up to 15 Gb/s. The power consumption of the multiplexer IC was measured to be as low as 34 mW at a supply voltage of -2V.

F/sub max/ enhancement in InP-based DHBTs using a new lateral reverse-etching technique

The DC and AC characteristics of InP/InGaAs PIN diodes have been investigated based on theoretical and experimental approaches. The switch performance of the PIN diode has been studied using a 2-D CAD simulator (Silvaco). Experimental data from a fabricated InP/InGaAs PIN diode was compared to the theoretical results. The developed InP/InGaAs PIN diode has demonstrated a 0.39 V turn on voltage, a 34 V breakdown voltage and a 5.23 THz cutoff frequency.

A Low DC-Power Multiplexer IC using an InP-based CML-MOBILE RTD/HBT Technology

A low-power RTD/HBT MOBILE (monostable-bistable transition logic element)-based D-flip flop is proposed and implemented using an InP-based monolithic RTD/HBT IC technology. The proposed MOBILE-based D-flip flop consists of a current mode logic (CML) type MOBILE core with complementary outputs and a CML-type SET/RESET latch, and has several advantages of the reduced device count and low-power consumption over the conventional D-flip flop based on a master/slave configuration. In addition, by using the CML-type SET/RESET latch in the proposed MOBILE-based D-flip flop, the high-speed operation and the compatibility with the conventional ECL interface have been achieved. The operation of the fabricated D-flip flop has been confirmed up to 32 Gb/s with a low-power consumption of 45 mW