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In this paper we present a system able to perform thermal treatments on lab-on-chip devices fabricated on glass substrates. The system includes a thin film resistor acting as heater and thin film hydrogenated amorphous silicon diodes acting as temperature sensors. An electronic system controls the lab-on-chip temperature through a Proportional-IntegralDerivative algorithm. In particular, an electronic board infers the system temperature measuring the voltage across the amorphous silicon diodes and drives the heater to achieve the set-point temperature. Taking into account the 16-bit ADC resolution and the sensors sensitivity, which is around 3.6 mV/C, we estimate that our system is able to detect temperature variation as low as 3.5·10-3 C

This paper presents the design, fabrication and characterization of a thin film heater functional for thermal treatments in lab-on-chip system. The spatial temperature distribution determined by different heater geometries has been studied through electro-thermal simulations by using COMSOL Multiphysics. The heater showing the more uniform temperature distribution has been subsequently fabricated and characterized. A very good agreement between modeled and measured data has been attained. Results show a spatial temperature distribution of about ±1°C over an area comparable to the heater area and a directly USB powered heater, demonstrating the suitability of the proposed device for lab-on-chip thermal applications

This work presents the design, fabrication and characterization of a system based on thin film technology for the selective detection of the natural fluorescence of Ochratoxin A. To this aim, the system optically couples an amorphous silicon photosensor with a long pass multi-dielectric filter, deposited on glass substrates. In particular, the filter rejects the wavelengths coming from the excitation source (centered at 340 nm) and transmits the emission spectrum (centered at 465 nm) of the mycotoxin, reducing therefore the background noise.\ud The basic structure of the a-Si:H photosensors is a p- type/intrinsic/n-type stacked junction, deposited by Plasma Enhanced Chemical Vapor Deposition at temperatures ranging from 210 to 300 °C. Its responsivity at 465 nm is equal to 185 mA/W. The long pass filter is an interferential filter, constituted by alternating layers of TiO2 and SiO2. It has been designed by using a freeware software, and deposited by electron beam Physical Vapor Deposition at 250 °C. A very good agreement between modeled and experimental data of transmittance and reflectance has been achieved. In particular, transmittance of the filter varies by almost four orders of magnitude between 360 nm and 400 nm, showing its suitability in rejecting the excitation light