Fully Integrated Interferometry-Based Reflectometer for High-Impedance Instrumentation

Abstract

Microwave imaging of nanoelectronic devices has turned a simple reflection coefficient measurement, usually carried out by a 50 Ω vector-network analyzer (VNA), into a high impedance instrumentation challenge. Interferometry-Based Reflectometers (IBR) have been found to be successful solutions in addressing this challenge. However, such solutions do not consider instrumentation of high impedance and high-frequency as well as minimization of environment variations in a comprehensive manner. In this study, these aspects are addressed jointly through the proposal of a fully-integrated IBR in the STMicroelectronics BiCMOS 55 nm technology. Three varactor samples having a capacitance ranging from 0.65 fF to 0.95 fF are measured at 17.6 GHz for demonstration. The fully-integrated IBR achieved a magnitude error below -35 dB, a phase error below 0.03 • , and an accuracy better than 59.7 aF. Moreover, C-V slope measurement error is better than 2.8 aF, which is ten times smaller than found in state-of-the-art IBR. Such betterment is explained by the monolithic integration of IBR and device-under-test (DUT) as implemented in this work.

Neuromorphic analog spiking-modulator for audio signal processing

“…Nevertheless, FS tonic spikes shape remains unchanged, as LTS spike frequency adaptation and the rebound spikes due to the post-inhibitory effect. Using varicap instead of MIM capacitance does not change the circuit behavior because the voltage variation (DV m 200 mV) is negligible if compared to the required bias voltage changes (V C % 2 V) according to measurement results [32]. The varicap of eNeuron circuit remains biased near the membrane rest potential ( $ À 70 mV), and under spike variations, the varicap filters its high-frequency components (short to V SS ).…”

Surface versus Performance Trade-offs: A Review of Layout Techniques

“…Figure 13(a) illustrates a passive LC-tank oscillator, the inductor is a differential coil of 557 pH. The capacitor is implemented using a differential varicap of C min = 1.2 fF and C max = 1.9 fF like the one measured in [38]. Expected oscillation frequency is 19 GHz, which requires a transistor f T ≥ 20 GHz.…”

A Portable Microwave Interferometry Sensor for Permittivity Detection Based on CCMRC

“…However, as a heterodyne transmitter/receiver architecture is used, which comprises of two multiplier stages and two independent signal sources, the high system complexity has not been fully resolved. Later on, the direct-conversion configurations, as well as interferometry reflectometers, were proposed to replace the heterodyne systems, and the corresponding extraction algorisms were updated accordingly [13], [25]- [28].…”