High-performance InGaAs-InAlAs-AlAs heterostructure barrier varactors (HBV's) have been designed, fabricated, and RF tested in a 250-GHz tripler block The devices with two barriers stacked on the same epitaxy are planar integrated with coaxial-, coplanar-, and strip-type configurations They exhibit state-of-the-art capacitance voltage characteristics with a zero-bias capacitance C/sub 3//sup 0/ of 1 fF//spl mu/m/sup 2/ and a capacitance ratio of 6:1 Experiments in a waveguide tripler mount show a 98-dBm (955-mW) output power for 107% conversion efficiency at 2475 GHz This is the highest output power and efficiency reported from an HBV device at J-band (220-325 GHz)

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Fabrication and performance of InP-based heterostructure barrier varactors in a 250-GHz waveguide tripler

Design and test data for a full waveguide band MMIC tripler using anti-parallel Schottky diodes are reported in this paper. The circuit outputs between -3.7 dBm and +2.0 dBm from 75 to 110 GHz. When tuned for power flatness, the output is between -4.6 dBm and -1.3 dBm across the band. The conversion efficiency is about 1.5% in both cases. To the authors' knowledge, this is the first reported MMIC frequency tripler to cover the entire W-band.

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A full waveguide band MMIC tripler for 75-110 GHz

This letter presents an optimized single-stage MMIC tripler with W-band output frequency (76.5 GHz). The circuit is based on an 0.15 /spl mu/m gate-length AlGaAs/InGaAs/GaAs PHEMT. By using a class AB transistor bias point and carefully selecting its input and output terminations, a high conversion gain of -4.3 dB for an 8.5 dBm input signal and a saturated output power of 7 dBm have been obtained. To our knowledge, these results represent the best performance reported up to date for an active frequency tripler with W-band output frequency.

An optimized 25.5-76.5 GHz PHEMT-based coplanar frequency tripler

We present a high-power InAlAs/InGaAs/InP heterostructure barrier varactor (HBV) frequency tripler. The HBV device topology was designed for efficient thermal dissipation and high efficiency. To verify simulations, the device was flip-chip soldered onto embedding microstrip circuitry on an aluminum nitride substrate. This hybrid circuit was then mounted in a waveguide block without any movable tuners. From the resulting RF measurements, the maximum output power was 195 mW at 113 GHz, with a conversion efficiency of 15%. The measured 3-dB bandwidth was 1.5%

https://publications.lib.chalmers.se/records/fulltext/local_40853.pdf

A 0.2-W Heterostructure Barrier Varactor Frequency Tripler at 113 GHz

Single (SHBV) and dual (DHBV) heterostructure barrier varactors with AlAs/In0.52Al0.48As bolocking conductionlayers have been fabricated and characterized. The devices, whose electrical properties scale with layer complexity, exhibit, for a DHBV scheme, leakage currents as low as 10 A/cm² at 12V, a zero bias capacitance of 1 fF/micro m², and capacitance ratio of 5:1.

High performance InP-based heterostructure barrier varactors in single and stack configuration

Conventional multi-stack quantum barrier varactor (MSQBV) diodes on GaAs suffer from leaky barriers and low breakdown voltage, which limits their performance in high-power applications. Using a lattice-matched InGaAs/InAlAs/InGaAs barriers on InP we have grown a new 10-stack device. Measurement results are presented that demonstrate low series resistance, large capacitance modulation, and significantly higher breakdown voltage than previously reported devices. The power capability of this new device has been investigated by simulations and measurements. An experiment in a waveguide tripler circuit shows a 19.6 dBm output power at 93 GHz. This is the highest output power reported from a single QBV device at W-band. >

A W-band medium power multi-stack quantum barrier varactor frequency tripler

The authors report a planar W-band frequency tripler based on a symmetrical multi-stack quantum barrier varactor (MSQBV). The circuit is realised using a standard hybrid circuit fabrication procedure. A prototype is fabricated and tested, a +3 dBm of output power is obtained at 90 GHz.

A. Rahal

Papers

A W-band medium power multi-stack quantum barrier varactor frequency tripler

Planar multi-stack quantum barrier varactor tripler evaluation at W-band