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This paper proposes an integrated layered doped and undoped amorphous silicon thin-film based temperature sensing device. Temperature sensing performance has been measured for thin film p-i-n (p-type- intrinsic-n-type) configuration-based diode. Linear dependency of voltage on the temperature for forward-biased diode at a constant bias current is demonstrated in the temperature range of 30 – 200 °C. Further, the same device has been introduced with double-walled carbon nanotubes (DWCNTs) to improve the linearity of the sensor. Comparative performance of two configurations p-i-n and p-i-n/DWCNTs for temperature sensing application has been studied. Moreover, this paper discussed the effect of the DWCNTs on the sensor parameters such as sensitivity, S and coefficient of determination, R2. The maximum sensitivity of the sensor, 22.34 mV/ °C for p-i-n configured device and 21.06 mV/°C for p-i-n/DWCNTs configuration in a biasing current range of 10– 60 mA have been found. We achieved a maximum value of the coefficient of determination equal to 0.99889 for a p-i-n configuration and 0.99922 for a p-i-n/DWCNTs configured device.

The microcrystalline hydrogenated-silicon (μc-Si: H) (also called polymorphous silicon) consisting a two-phase mixture of amorphous and structured silicon is being used for electronic or optoelectronic based thin-film devices. The μc-Si: H thin films are deposited using radio frequency (13.56 MHz) Plasma Enhanced Chemical Vapour Deposition (RF-PECVD) by varying doping gases (diborane (B2H6) and phosphine (PH3)) flow and hydrogen-silane dilution ratio (R = H2/SiH4) to optimize the crystalline fraction and electrical conductivity. Micro-Raman spectroscopy is used to investigate these effect on the transition fraction regime from amorphous into micro-structured silicon. Qualitative and quantitative properties have been studied by deconvolution of the micro Raman spectra which allows to determine the crystalline fraction in the film and also some investigation regarding the correlation between electrical and structural properties are presented for different annealing temperature (from 300 to 550 °C) and various film thickness ranges (10–100 nm). In this work, we present the characterization of thin films (both doped and undoped) deposited at the temperature of 250 °C on quartz substrate after annealed at 550 °C in N2-ambient, as a result crystallinity percentage up to 90% for p-type, 96% for n-type and 80% for undoped films are achieved. A detailed characterization of the microcrystalline silicon (μc-Si: H) has been demonstrated in this paper: structural properties through Raman spectroscopy, electrical properties through Four-point probe station and optical properties using Ellipsometer.

We generalize the notion of k-radical of Green’s \({\overline{\mathcal{J}}}\)-relation, study the decompositions of semirings and investigate the semirings on which the powers and transitive closures of k-radicals are distributive lattice congruences.