Integrated Circuits Based on 300 GHz fT Metamorphic HEMT Technology for Millimeter-Wave and Mixed-Signal Applications

Advanced circuits based on metamorphic HEMT (MHEMT)technologies on 4 ”GaAs substrates for both millimeter-wave,and mixed- signal applications are presented.Extrinsic cut-off frequencies of ft =293 GHz and fmax =337 GHz were achieved for a 70 nm gate length metamorphic HEMT echnology.The MMIC process obtains high yield on transistor and circuit level.Single-stage low-noise amplifiers demonstrate a small signal gain of 13 dB and a noise figure of 2.8 dB at 94 GHz.An amplifier MMIC developed for D-Band operation features a gain of 15 dB at 160 GHz.The achieved results are comparable to state- of-the-art InP-based HEMT technologies.In order to realize 80 Gbit/s digital circuits,a process with 100 nm gate length enhancement type HEMTs with a transit frequency of 200 GHz is used.Three metalization layers are available for interconnects.The parasitic capacitance of the interconnects is kept low by using BCB and plated air bridge technology.Based on this process,static and dynamic frequency dividers achieve a maximu toggle frequency of 70 GHz and 108 GHz,respectively

Low noise amplifiers for MetOp-SG

We present low-noise amplifiers (LNA) that have been developed in the framework of two pre-qualification ESA projects for frequencies between 54 and 229 GHz for the METOP-SG satellite program. The main goal of these satellites is water vapor detection in atmospheric science and weather forecasting which advances the current state of the art for the metamorphic high electron mobility transistor (mHEMT) technology. The MMIC amplifiers are based on the In0.52Al0.48As/In0.8Ga0.2As/In0.53Ga0.47As heterostructure and utilize transistors with a gate length of 50 nm. On-wafer measurements will be presented for all frequency bands as well as results of packaged LNAs

Wireless THz link with optoelectronic transmitter and receiver

Photonics might play a key role in future wireless communication systems that operate at terahertz (THz) carrier frequencies. A prime example is the generation of THz data streams by mixing optical signals in high-speed photodetectors. Over previous years, this concept has enabled a series of wireless transmission experiments at record-high data rates. Reception of THz signals in these experiments, however, still relied on electronic circuits. In this paper, we show that wireless THz receivers can also greatly benefit from optoelectronic signal processing techniques, in particular when carrier frequencies beyond 0.1 THz and wideband tunability over more than an octave is required. Our approach relies on a high-speed photoconductor and a photonic local oscillator for optoelectronic downconversion of THz data signals to an intermediate frequency band that is easily accessible by conventional microelectronics. By tuning the frequency of the photonic local oscillator, we can cover a wide range of carrier frequencies between 0.03 and 0.34 THz. We demonstrate line rates of up to 10 Gbit/s on a single channel and up to 30 Gbit/s on multiple channels transmitted over a distance of 58 m. To the best of our knowledge, our experiments represent the first demonstration of a THz communication link that exploits optoelectronic signal processing techniques both at the transmitter and the receiver

Wireless THz link with optoelectronic transmitter and receiver

Photonics might play a key role in future wireless communication systems that operate at terahertz (THz) carrier frequencies. A prime example is the generation of THz data streams by mixing optical signals in high-speed photodetectors. Over previous years, this concept has enabled a series of wireless transmission experiments at record-high data rates. Reception of THz signals in these experiments, however, still relied on electronic circuits. In this paper, we show that wireless THz receivers can also greatly benefit from optoelectronic signal processing techniques, in particular when carrier frequencies beyond 0.1 THz and wideband tunability over more than an octave is required. Our approach relies on a high-speed photoconductor and a photonic local oscillator for optoelectronic downconversion of THz data signals to an intermediate frequency band that is easily accessible by conventional microelectronics. By tuning the frequency of the photonic local oscillator, we can cover a wide range of carrier frequencies between 0.03 and 0.34 THz. We demonstrate line rates of up to 10 Gbit/s on a single channel and up to 30 Gbit/s on multiple channels transmitted over a distance of 58 m. To the best of our knowledge, our experiments represent the first demonstration of a THz communication link that exploits optoelectronic signal processing techniques both at the transmitter and the receiver

Monolithisch integrierte Millimeterwellenverstärker für bildgebende Systeme

Im Rahmen der vorliegenden Arbeit wurden monolithisch integrierte Millimeterwellenverstärker für den Einsatz in aktiven und passiven bildgebenden Systemen im Frequenzbereich der atmosphärischen Fenster bei 94 GHz, 140 GHz und 220 GHz entwickelt. Ziel ist eine umfassende Untersuchung geeigneter Schaltungskonzepte sowie der erfolgreiche Aufbau der koplanaren Sende- und Empfangsschaltkreise innerhalb von Millimeterwellenmodulen in Hohlleitertechnik

Monolithisch integrierte Millimeterwellenverstärker für bildgebende Systeme

Im Rahmen der vorliegenden Arbeit wurden monolithisch integrierte Millimeterwellenverstärker für den Einsatz in aktiven und passiven bildgebenden Systemen im Frequenzbereich der atmosphärischen Fenster bei 94 GHz, 140 GHz und 220 GHz entwickelt. Ziel ist eine umfassende Untersuchung geeigneter Schaltungskonzepte sowie der erfolgreiche Aufbau der koplanaren Sende- und Empfangsschaltkreise innerhalb von Millimeterwellenmodulen in Hohlleitertechnik

Monolithisch integrierte Millimeterwellenverstärker für bildgebende Systeme

Im Rahmen der vorliegenden Arbeit wurden monolithisch integrierte Millimeterwellenverstärker für den Einsatz in aktiven und passiven bildgebenden Systemen im Frequenzbereich der atmosphärischen Fenster bei 94 GHz, 140 GHz und 220 GHz entwickelt.Ziel ist eine umfassende Untersuchung geeigneter Schaltungskonzepte sowie der erfolgreiche Aufbau der koplanaren Sende- und Empfangsschaltkreise innerhalb von Millimeterwellenmodulen in Hohlleitertechnik

Flip-Chip Integration of Power HEMTs: A Step Towards a GaN MMIC Technology

In this paper, flip-chip integration is demon-stratedas a method for faster progress towards a GaN MMIC technology by separating the development of active devices and passive matching circuits. This approach offers distinct advantages in the verification of passive components realized on a 2” SiC substrate. A proven 0 .3 µm GaAs PHEMT technology was used for the transistors that allowed to reproducibly verify both, the flip-chip transitions and the behaviour of the coplanar SiC structures. As an example, three X-band amplifiers in flip-chip technology are presented that demonstrate the feasibility of the technology

On-chip post-production tuning of I/Q frequency converters using adjustable coupler terminations

This paper presents a broadband integrated double balanced I/Q-upconverter at 73.5GHz in a 50nm InGaAs based metamorphic high electron mobility transistor technology including Lange couplers with voltage-controlled variable termination resistance. The variable resistance is implemented by using resistive FETs. This MMIC is designed for broad band communication with controllable LO suppression at the output. Introducing Lange couplers with voltage-controlled termination resistance offers a post-production measure to optimize MMICs with respect to I/Q-imbalance and LO isolation. In comparison to conventional 50 termination resistances the LO isolation could be improved by up to 12 dB over a bandwidth of 20 GHz while maintaining near constant conversion gain