STMicroelectronics

About: STMicroelectronics is a company organization based out in Geneva, Switzerland. It is known for research contribution in the topics: Transistor & Signal. The organization has 17172 authors who have published 29543 publications receiving 300766 citations. The organization is also known as: SGS-Thomson & STM.

Capacitive fingerprint sensor with protective coating containing a conductive suspension

Abstract: A capacitive fingerprint sensor includes a polymeric protective coating defining a sensing surface and having conductive particles suspended therein. The conductive particles act as parallel strings of series capacitors to couple the capacitance the fingerprint-bearing skin of a user's finger applied to the sensing surface to capacitive sensing elements beneath the protective coating. The polymeric material of the coating is durable and scratch resistant. The conductive particles enable use of a protective coating of 10 to 20 microns in thickness while providing a high degree of sensitivity and image resolution.

SiOxFy passivation layer in silicon cryoetching

Abstract: The SiOxFy passivation layer created on structure sidewalls during silicon cryoetching is investigated. This SiOxFy passivation layer formation strongly depends on O2 content, temperature and bias. It is a fragile layer, which mostly disappears when the wafer is warmed up to ambient temperature. A mass spectrometer was used to analyze the desorbed species during the warm-up and using this instrument allowed us to find a large signal increase in SiF3+ between −80°C and −50°C. SiF4 etching products can participate in the formation of the passivation layer as it is shown by a series of test experiments. SiF4∕O2 plasmas are used to form a thin SiOxFy layer on a cooled silicon wafer. Thickness and optical index of this thin film can be determined by in situ spectroscopic ellipsometry. It is shown that the passivation layer spontaneously desorbs when the silicon wafer temperature increases in good agreement with the mass spectrometry analysis. Two physical mechanisms are proposed to explain the SiOxFy passivati...

A Framework for Modeling, Simulation and Automatic Code Generation of Sensor Network Application

Abstract: Showing functional correctness by simulation before implementation, and preserving it by automated code generation, is extremely useful to reduce the development time for an embedded application. This is even more true for wireless sensor networks, since their nodes often provide very rudimentary debugging facilities, and sufficiently large networks for realistic analysis may be expensive to deploy. While this approach, also known as model-based design, is becoming quite standard for several domains that have similar constraints as wireless sensor networks, such as automotive electronics, there is a lack of tools for this purpose in the WSN world. In order to fill this gap, in this paper we present a framework (based on Simulink, Stateflow and Embedded Coder) in which an engineer can create sensor network components (both at the application and at the protocol level) that can be used as building blocks to model, simulate and automatically generate code for different underlying platforms and operating systems.

A G/sub m/-C low-pass filter for zero-IF mobile applications with a very wide tuning range

Abstract: A third-order G/sub m/-C Butterworth low-pass filter implementing G/sub m/-tuning and G/sub m/-switching to maximize the tuning range is described. This filter is intended to be used as a channel-selection/anti-aliasing filter in the analog baseband part of a zero-IF radio receiver architecture for multimode mobile communications. Its G/sub m/-switching feature allows extending the tuning range and adapting the power consumption. The filter's cutoff frequency ranges from 50 kHz to 2.2 MHz. An Input IP3 of up to +18 dBV/sub p/ is achieved, for a total worst-case power consumption of 7.3 mW for both I and Q paths, and an effective area of less than 0.5 mm/sup 2/ in a 0.25-/spl mu/m SiGe BiCMOS process. A new figure of merit is introduced for comparison of published low-pass tunable filters including noise, linearity, and tuning range.

Integrated waveguide PIN photodiodes exploiting lateral Si/Ge/Si heterojunction.

Abstract: Germanium photodetectors are considered to be mature components in the silicon photonics device library. They are critical for applications in sensing, communications, or optical interconnects. In this work, we report on design, fabrication, and experimental demonstration of an integrated waveguide PIN photodiode architecture that calls upon lateral double Silicon/Germanium/Silicon (Si/Ge/Si) heterojunctions. This photodiode configuration takes advantage of the compatibility with contact process steps of silicon modulators, yielding reduced fabrication complexity for transmitters and offering high-performance optical characteristics, viable for high-speed and efficient operation near 1.55 μm wavelengths. More specifically, we experimentally obtained at a reverse voltage of 1V a dark current lower than 10 nA, a responsivity higher than 1.1 A/W, and a 3 dB opto-electrical cut-off frequency over 50 GHz. The combined benefits of decreased process complexity and high-performance device operation pave the way towards attractive integration strategies to deploy cost-effective photonic transceivers on silicon-on-insulator substrates.