Bassam Khamaisi

A 210–227 GHz Transmitter With Integrated On-Chip Antenna in 90 nm CMOS Technology

This paper presents a transmitter operating in the 210-227 GHz in 90 nm CMOS, based on a Colpitts VCO. The third harmonic of the generated VCO fundamental signal is coupled to an on-chip dipole antenna. A simplified model is presented for the operation and the design of the circuit, which compares well with simulated and measured results. The transmitter achieves an EIRP of +1.8 dBm at 217 GHz and directivity of about +10 dBi. The circuit consumes 128 mW of DC power and an area of 0.53 mm2.

A 209–233 GHz Frequency Source in 90 nm CMOS Technology

This letter presents a J-band signal source based on a third harmonic generation of a differential Colpitts voltage controlled oscillator (VCO). The source covers a frequency range from 209.3 to 233.3 GHz, which corresponds to a 10.8% total tuning range. This is the widest tuning range in a J-band source signal reported to date. The VCO was fabricated using a 90 nm Mixed-Mode/RF CMOS process; it provides - 6.2 Bm output power at 228 GHz, while consuming 48 mA from a 1.8 V supply, and an estimated phase noise of - 90.5 dBc/Hz at 1 MHz offset from the carrier.

Electrical performance of silicon-on-insulator field-effect transistors with multiple top-gate organic layers in electrolyte solution.

The utilization of field-effect transistor (FET) devices in biosensing applications have been extensively studied in recent years. Qualitative and quantitative understanding of the contribution of the organic layers constructed on the device gate, and the electrolyte media, on the behavior of the device is thus crucial. In this work we analyze the contribution of different organic layers on the pH sensitivity, threshold voltage, and gain of a silicon-on-insulator based FET device. We further monitor how these properties change as function of the electrolyte screening length. Our results show that in addition to electrostatic effects, changes in the amphoteric nature of the surface also affect the device threshold voltage. These effects were found to be additive for the first (3-aminopropyl)trimethoxysilane linker layer and second biotin receptor layer. For the top streptavidin protein layer, these two effects cancel each other. The number and nature of amphoteric groups on the surface, which changes upon the formation of the layers, was shown also to affect the pH sensitivity of the device. The pH sensitivity reduces with the construction of the first two layers. However, after the formation of the streptavidin protein layer, the proteins multiple charged side chains induce an increase in the sensitivity at low ionic strengths. Furthermore, the organic layers were found to influence the device gain due to their dielectric properties, reducing the gain with the successive construction of each layer. These results demonstrate the multilevel influence of organic layers on the behavior of the FET devices.

130-320-GHz CMOS Harmonic Down-Converters Around and Above the Cutoff Frequency

We present an analytical model, design, and measurement results on fundamental, harmonic, and subharmonic down conversion mixing approaches in 65-nm CMOS around and above the transistor cutoff frequency fmax, targeting submillimeter-wave operation. Analytical expressions for the mixing approaches are derived and compared with the simulation and measurement results. To investigate how to improve the performance of a passive mixer around and beyond fmax, the relation between local oscillator (LO) harmonics (including both the harmonic amplitude and phase), mixer gate bias, and conversion gain is studied. To demonstrate mixing approaches, we present integrated 160- and 280-GHz down-converters with integrated LO manufactured in 65-nm CMOS process with fmax= 210 GHz. The LO in both down-converters is based on exploiting higher harmonics of a differential Colpitts topology voltage-controlled oscillator (VCO). Passive conversion losses of 22 and 25.5 dB are obtained over the 150-180-GHz and the 230-290-GHz frequency range, respectively. Two additional versions of the down converter at 170 and 280 GHz, respectively, without integrated VCO are also presented to examine the mixer performance in the 110-325-GHz range.

THz Sensing and Imaging with Silicon Field-effect Transistors up to 9 THz

The detection of THz radiation is linked with mainstream silicon technology using plasmonic mixing in MOSFETs. We report imaging in heterodyne and sub¬harmonic-mixing mode for enhanced dynamic range, and present a 220-GHz all-silicon imager.

A +6dBm 128GHz source module with full F-band waveguide package and wirebonded CMOS chip

In this paper, a packaged F-band transmitter in CMOS 65 nm technology is presented. The integrated circuit is based is based on a x9 active multiplying chain from Ku-band to F-band. The circuit was packaged and connectorized demonstrating the possibility of using wire-bonds around 130 GHz with low insertion loss. The microstrip-to-waveguide transition developed introduces insertion loss below 1 dB from 85 to 145 GHz. On-chip probing of the circuit showed a maximum output power of +8 dBm at 124 GHz with a 3 dB bandwidth of 9.8 % (117-129 GHz). The packaged circuit showed a maximum output power of +6 dBm at 128 GHz resulting in a package RF path insertion loss of 2 dB in average through the circuit -3 dB frequency bandwidth (117-133 GHz).

On-chip transmitter with an EIRP of +2.8 dBm at 217 GHz in 90 nm CMOS

In this paper, we present a transmitter operating in the 210-227 GHz in 90-nm CMOS, based on a Colpitts VCO. The third harmonic of the generated VCO fundamental signal is coupled to an on-chip dipole antenna. The silicon substrate of the CMOS chip is thinned from 280 μm to 80 μm in order to improve the performance of the transmitter in terms of effective isotropic radiated power (EIRP) and directivity. The transmitter achieves an EIRP of +2.8 dBm at 217 GHz and a directivity of about +13.1 dBi with a total power radiated of -10.3 dBm. The circuit consumes 134 mW of DC power and an area of 0.53 mm2.