J.-F. Luy

Active SIMMWIC-antenna for automotive applications

An active SIMMWIC-Antenna (Silicon Monolithic Millimeterwave Integrated Circuit) for vehicular technology in the frequency range around 76.5 GHz is presented. This active antenna acts as a transceiver and is well suited for low-cost integrated sensor systems for automotive applications. The monolithic active antenna embedded in a synchronization network requires only 3.2/spl times/2.6 mm/sup 2/ chip size. Using subharmonic injection locking frequency tuning and stabilization is realized. With an injection power of 0 dBm we measured a tuning range of 300 MHz. To our knowledge, this is the first synchronizable monolithic integrated active antenna suited for automotive applications in the frequency band around 76.5 GHz.

47 GHz SiGe-MMIC oscillator

A 47 GHz MMIC SiGe-HBT oscillator on high-resistivity silicon is presented. An output power of 13.1 dBm and an efficiency of 13.6% is measured. The oscillator exhibits a phase-noise of -99.31 dBc/Hz at 100 kHz off-carrier. These results represent a new record value for SiGe-HBT based oscillators.

A SIMMWIC 76 GHz front-end with high polarization purity

An integrated active antenna with a polarization purity better than 28 dB and a radiated power of 8 dBm at 75.7 GHz is presented. The linearly polarized radiator consists of a planar resonant antenna and a transit-time diode monolithically integrated on a silicon substrate. This active antenna finds various applications in low-cost multi-channel sensor systems, e.g. for object classification. Guidelines for the design are discussed. The characterization of the fabricated SIMMWIC devices includes measurements of output power, polarization purity, and far-field pattern. Moreover, the oscillation frequency of the devices has been successfully stabilized using subharmonic injection locking. The FM noise behavior of the locked oscillator has been characterized. The measured results are presented and compared to theoretical calculations.

Modelling of passive elements for coplanar SiGe MMIC's

As the first step in the development of coplanar SiGe MMICs, modelling and experimental results on passive components are presented. The investigations demonstrate that parasitic effects induced by passivation of high-resistivity silicon substrates play an important role. Efficient CAD tools are developed and verified by comparison with measurements.<<ETX>>

Coplanar Monolithic Silicon Impatt Transmitter

A coplanar W-band transmitter incorporating a monolithically integrated IMPATT diode in a self radiating slot line resonator has been designed and fabricated with molecular beam epitaxy (MBE) on a high resistivity silicon substrate. A pulsed radiated output power of 7 mW at 109 GHz was measured.

Silicon Monolithic Millimeter Wave Impatt Oscillators

The good efficiency of silicon IMPATT diodes in the upper frequency range and the relatively high thermal conductivity of silicon lead to the concept of a monolithically integrated coplanar IMPATT oscillator. This concept is realized in a prototype for W-band frequencies in CW operation. First measurements indicate oscillations at a frequency of 76 GHz with a continuous wave output power of about 1 mW.

Silicon millimeter-wave circuits for receivers and transmitters

Two silicon monolithic circuits, a 90-GHz-band monolithic integrated Schottky diode receiver fabricated on a highly insulating silicon substrate, and a planar W-band oscillator, hybrid integrated on a highly insulating silicon substrate with double drift region IMPATT diodes, are presented. The receiver consists of the monolithic Schottky diode and a planar antenna structure on one silicon chip. The receiver sensitivity is 65 mu W/cm. The receiver antenna half-power beamwidth is 23 degrees and the side-lobe attenuation is 12 dB. The continuous-wave oscillator output power is greater than 20 mW and the efficiency is more than 1%. The hybrid IMPATT oscillators show good characteristics for low current densities. However, for higher current densities bias oscillations occur and the microwave power nearly vanishes.<<ETX>>

Simmwic Capacitive RF Switches

Capacitive RF metal membrane switches have been fabricated on pyrex and high-resistivity silicon wafer using CPW transmission lines and a modified air-bridge technology. Actuation voltage down to 25 V has been achieved. The switches exhibit low loss (<0.4 dB @ 35GHz) with good isolation (35 dB @ 35 GHz).

A Silicon Technology for Active High Frequency Circuits

Monolithic integrated IMPATT diodes are manufactured as millimeter wave power generators in slot line resonator-antennas. Silicon molecular beam epitaxy (Si-MBE) is used for the growth of the active layers. A fabrication process with a self stopping etchant, self aligned contacts, silicon nitride passivation and air-bridge technology is used. The emitted radiation of the millimeter wave transmitter chip is 2.6 mW at 90.6 GHz in cw-operation and 50 mW at 92 GHz in pulsed operation.

Planar 100 GHz Silicon Detector Circuits

On high resistive silicon substrates Schottky barrier diodes have been monolithically integrated with planar antenna structures. The Schottky barrier diodes were fabricated on n+ diffusion regions with thin epitaxial layers grown by molecular beam epitaxy. Low series resistance (≪ 6 ω), ideality factor of less than 1.1 and cut-off frequencies up to 1 THz have been achieved. The maximum sensitivity of the detector-was 90 mV/(mW cm-2) at 94 GHz.