Please login first
Florin Udrea      
Timeline See timeline
Florin Udrea published an article in March 2019.
Top co-authors See all
Andrea De Luca

43 shared publications

Department of Engineering, University of Cambridge, Cambridge CB3 0FF, UK

Daniel Popa

30 shared publications

Department of Engineering, University of Cambridge, Cambridge CB3 0FA, UK

Syed Zeeshan Ali

9 shared publications

AMS Sensors UK Ltd., Deanland House, 160 Cowley Road, Cambridge CB4 0DL, UK

Ethan Gardner

5 shared publications

Department of Engineering, University of Cambridge, Cambridge CB3 0FF, UK

Gaël Loubet

3 shared publications

LAAS-CNRS, Université de Toulouse, CNRS, INSA, UPS, 31400 Toulouse, France

Publication Record
Distribution of Articles published per year 
(2007 - 2019)
Total number of journals
published in
Publications See all
Article 0 Reads 0 Citations LoRaWAN Battery-Free Wireless Sensors Network Designed for Structural Health Monitoring in the Construction Domain Gaël Loubet, Alexandru Takacs, Ethan Gardner, Andrea De Luca... Published: 28 March 2019
Sensors, doi: 10.3390/s19071510
DOI See at publisher website ABS Show/hide abstract
This paper addresses the practical implementation of a wireless sensors network designed to actualize cyber-physical systems that are dedicated to structural health monitoring applications in the construction domain. This network consists of a mesh grid composed of LoRaWAN battery-free wireless sensing nodes that collect physical data and communicating nodes that interface the sensing nodes with the digital world through the Internet. Two prototypes of sensing nodes were manufactured and are powered wirelessly by using a far-field wireless power transmission technique and only one dedicated RF energy source operating in the ISM 868 MHz frequency band. These sensing nodes can simultaneously perform temperature and relative humidity measurements and can transmit the measured data wirelessly over long-range distances by using the LoRa technology and the LoRaWAN protocol. Experimental results for a simplified network confirm that the periodicity of the measurements and data transmission of the sensing nodes can be controlled by the dedicated RF source (embedded in or just controlled by the associated communicating node), by tuning the radiated power density of the RF waves, and without any modification of the software or the hardware implemented in the sensing nodes.
Article 0 Reads 0 Citations Membrane Deflection and Stress in Thermal Flow Sensors Claudio Falco, Ethan L. W. Gardner, Andrea De Luca, Nicolas ... Published: 11 December 2018
Proceedings, doi: 10.3390/proceedings2131089
DOI See at publisher website ABS Show/hide abstract
The effect of membrane deflection has been investigated for thermal flow sensors. Catastrophic membrane breakage is a common occurrence in membrane based thermal flow sensors due to thermal expansion and internal stresses. This work analyses three sensors comprising a tungsten heater embedded in buried oxide membrane with a silicon nitride passivation layer, the use of back etching creates a cavity underneath to reduce the thermal conduction. The investigation is done using interferometry to measure the membrane shape at room and operating temperature for three membranes of different sizes. As expected, the deflection increases with temperature up to 15 µm at operating temperature and with the reduction of membrane size the deflection is reduced to a minimum of 3 µm for the smallest membrane. The lower deflection measured in devices with a smaller cavity can be related to a reduced internal stress, improving the long term stability.
Article 1 Read 0 Citations On-Chip Thermal Insulation Using Porous GaN Bogdan F. Spiridon, Peter H. Griffin, John C. Jarman, Yingju... Published: 10 December 2018
Proceedings, doi: 10.3390/proceedings2130776
DOI See at publisher website ABS Show/hide abstract
This study focuses on the thermal characterization of porous gallium nitride (GaN) usingan extended 3ω method. Porous semiconductor materials provide a solution to the need for on-chipthermal insulation, a fundamental requirement for low-power, high-speed and high-accuracythermal sensors. Thermal insulation is especially important in GaN devices, due to the intrinsicallyhigh thermal conductivity of the material. The results show one order of magnitude reduction inthermal conductivity, from 130 W/mK to 10 W/mK, in line with theoretical predictions for porousmaterials. This achievement is encouraging in the quest for integrating sensors with opto-, powerandRF-electronics on a single GaN chip.
Article 0 Reads 0 Citations A CMOS-Based Thermopile Array Fabricated on a Single SiO2 Membrane Richard Hopper, Syed Zeeshan Ali, Sophie Boual, Andrea De Lu... Published: 22 November 2018
Proceedings, doi: 10.3390/proceedings2130878
DOI See at publisher website ABS Show/hide abstract
We present a novel thermopile-based infrared (IR) sensor array fabricated on a single CMOS dielectric membrane, comprising of poly-silicon p+ and n+ elements. Processing of the chip is simplified by fabricating the entire array on a single membrane and by using standard CMOS Al metal layers for thermopile cold junction heatsinking. On a chip area of 1.76 mm × 1.76 mm, with a membrane size of 1.2 mm × 1.2 mm, we fabricated IR sensor arrays with 8 × 8 to 100 × 100 pixels. The 8 × 8 pixel device has
Article 0 Reads 0 Citations Evaluation of thin film p-type single crystal silicon for use as a CMOS Resistance Temperature Detector (RTD) Zahid Mehmood, Mohtashim Mansoor, Ibraheem Haneef, S. Zeesha... Published: 01 November 2018
Sensors and Actuators A: Physical, doi: 10.1016/j.sna.2018.09.062
DOI See at publisher website
Article 0 Reads 2 Citations A maskless etching technique for fabrication of 3D MEMS structures in SOI CMOS devices Mohtashim Mansoor, Ibraheem Haneef, Andrea De Luca, John Cou... Published: 09 May 2018
Journal of Micromechanics and Microengineering, doi: 10.1088/1361-6439/aabe0d
DOI See at publisher website