RH sensors have been made using porous polysilicon and porous SiC, both of which can also be made porous by electrochemical anodisation in HF, similarly to single crystal silicon. We show that polysilicon can be incorporated into a humidity sensor enabling a reduction (compared to single-crystal porous Si) of the effect of temperature on humidity measurements. We show that also porous SiC can a...

In this paper, we present the effect of varying humidity levels on the electrical parameters and the multi frequency response of the electrical parameters of an organic-inorganic composite (PEPC+NiPc+Cu2O)-based humidity sensor. Silver thin films (thickness ~200 nm) were primarily deposited on plasma cleaned glass substrates by the physical vapor deposition (PVD) technique. A pair of rectangula...

Ionic polymer-metal composites (IPMCs) exhibit humidity-dependent sensing behavior when operating in air, which weakens the reliability of the IPMC sensors. To better understand the underlying physics of this behavior and capture the humiditydependence analytically, in this paper the influence of the ambient humidity on IPMC sensors is characterized and modeled from a physical perspective. In p...

RFID, as a low cost technology with a long life time, provides great potential for transmitting sensor data in combination with the ordinary ID number. The sensor can, for example, be integrated either in the chip or in the antenna of an RFID tag. This thesis focuses on the design of antenna-based UHF RFID sensor tags as wireless sensors at the lowest possible cost level compatible with standar...

Sensor nodes are increasingly deployed in many environments. Most of these nodes feature onboard sensor chips to measure environmental data such as humidity, temperature and light. In this paper, we show that seemingly innocuous and non-sensitive data such as humidity measurements can disclose private information such as human presence. We conduct several experiments using Telos motes running T...

The synthesis parameters and results of investigation of gas sensing properties of tin oxide nanoparticles produced by spark ablation are presented. The nanoparticles have sizes below 30 nm and their specific surface area is about 40 m2/g. In order to study the gas sensing properties, a special structure comprising heater, barrier layers and contact pads was utilized. The resistance of the sens...