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This paper investigates the high-temperature thermal response of a Ni/SiC-Schottky diode with a severe degree of contact in homogeneity. Forward characteristics, visibly affected by non-uniform Schottky barrier height in the 25°C-450°C domain are very accurately reproduced using a model based on parallel conduction. Constant sensitivity is established for the analyzed sample in the entire measurement temperature range. The impact of extracted parameters on sensitivity value is discussed. Results show that SiC-Schottky diodes with considerable contact inhomogeneity can be used as wide-range temperature sensors.

A Sense and Control Circuit (SCC) developed for amperometric concentration evaluation is redesigned, based on preliminary experimental investigations. This cost-effective circuit comprises a potentiostat for three-electrode electrochemical cell (biosensor) control and a transimpedance amplifier for cell current sensing. Stability, noise robustness and response time are improved, as demonstrated by experiments and simulations. SCC performances are evaluated in comparison with a professional system, by H2O2 concentration measurements.

A Smart Sensor used for measuring the concentration of chemical compounds in fluids/solutions is designed, implemented and tested. The sensor comprises a potentiostat employed for three-electrode electrochemical cell (biosensor) biasing, a transimpedance amplifier and a digital interfacing system. The stability of the potentiostat and the linearity of the transimpedance amplifier are theoretically and experimentally investigated. Finally, the high performances of the smart sensor are demonstrated by simulations and measurements.

SiC devices' electrical properties used as sensing mechanisms are demonstrated for two types of sensors. A Schottky barrier diode (SBD) is proposed as a temperature sensor while a MOS capacitor is used for gas (hydrogen) detection. A layout with different active contacts, having 200, 300 and 400µm diameters and similar technology is designed and used for fabricating both sensors. An automatic high temperature system is developed to test the sensors up to 450°C. The main electrical parameters of the SiC devices designed to operate as sensors are extracted using dedicated programs. The temperature detection sensitivity of the SBD is in range of 1.52–2.13mV/°C. For the gas sensor, a sensitivity peak of 120% is achieved for a H2 concentration over 1000 ppm. An industrial temperature probe based on SiC SBD was tested to monitor furnace temperature in the 100–400°C range in a cement factory.

In this paper it is described a design technique used to collect and analyse power devices characteristics in high temperatures domain. Following this technique, a complete hardware and software platform is built for thermal characterization of power devices.

A simple technology of 4H-SiC Schottky diode with oxide ramp termination is presented. The ramp is controlled by two undoped layers: an annealed (compact) oxide layer and as deposited layer, respectively.

A temperature probe based on 4H-SiC Schottky diodes is proposed. These diodes have been fabricated and characterized for temperature sensor applications. A conversion circuit to 4–20mA output current for ambient to maximum (400°C) input temperature was designed and tested.

A method for measuring low frequency biosignals is developed. A circuit based on biosignals amplifier for a methanol sensor is designed and simulated. The electrical simulations confirm the good behavior of the system at low currents and very high rejection at frequencies higher than 10Hz. The proposed method does not disturb the sensor behavior.

A compact analytical model of nanoscale MOS transistors which takes into account the effects of velocity saturation and channel length modulation is proven. Equations for the transfer and output characteristics and for the dynamic analogue parameters (transconductance and output resistance) are obtained, in the case of pMOS, as well as nMOS transistors. Experimental transfer and output characteristics of short channel devices match well with calculated curves based on the model, for different transistor geometries. A very good agreement of the new model with the experimental data for transconductance and output resistance is also obtained.

The validation of a new analytical model for the electrical characteristics of deep submicron MOS transistors is accomplished through theory-experiment comparison in this paper. The model is proven to be accurate in all predictions regarding the effect of velocity saturation on the parameters of nanoscale MOSFET: transconductance, transitions currents, etc. Experimental transfer characteristics of short channel devices match well with calculated curves based on the model, for different transistor geometries.

Extensive numerical simulations have been carried out to compare the electrical performance of ideal Schottky diodes on diamond and silicon carbide. The influences of the drift layer parameters on the off-state behaviour of the diodes are presented for both punch-through (PT) and non punch-through (nPT) structures. In PT case breakdown voltage was shown to be constant with the drift doping at low concentrations. Analytical expressions of the breakdown voltage variation with doping for nPT diodes are also included.