IOSR-JAP   Volume-1 ~ Issue-4 ~ July–August 2012

Paper Type	:	Research Paper
Title	:	Promising Application of Neodymium Oxide Nano Films in Microelectronics
Country	:	India
Authors	:	Arun Chandra Sarmah
	:	10.9790/4861-0140103

Abstract: The AC conduction mechanism of vacuum deposited Neodymium Oxide (Nd2O3) nano films with Aluminium top and counter electrodes were investigated at temperature range 302-528 K and within the thickness range 90-175 nm. The variations of capacitance (C) with frequency (0.06-50 kHz) at different temperatures were also observed. It was found that the capacitance was frequency dependent at all temperatures but almost independent in the high frequency range beyond 1 kHz. From the variation of dielectric loss (tanδ) with frequency it was seen that tanδ values decrease rapidly with frequency and attains a minimum value. The variation of C with T at various frequencies was also studied and was found that C almost remain constant almost upto 440 K and then increases sharply with temperature. At low frequencies C increases sharply with temperature. From the tanδ versus T characteristics at different frequencies it was observed that in the temperature range upto 460 K. tanδ almost remained constant but increased sharply with T at frequencies below 1 kHz or below. A non-linear variation of 1/C2 with voltage did not indicate the presence of Schottky barriers. Nd2O3 nano films show low capacitance density 0.0021 μF cm-2 and low dielectric loss 0.008 at 1 kHz and at 300 K. On account of stable properties, low dielectric loss and high dielectric constant the application of Nd2O3 nano films in electronic microcircuits will give promising result.
Keywords: AC conduction, activation energy, capacitance density, dielectric loss, dielectric constant

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Paper Type	:	Research Paper
Title	:	Preliminary Measurements of Radon Radiations in "Bare Mode" In Rampur District of Western U.P. (India)
Country	:	India
Authors	:	M.S.A. Khan, M. Tariq, R.B.S.Rawat
	:	10.9790/4861-0140407

Abstract: Measurement of radon, thoron concentration and their daughter products in a dwelling of Rampur city and in the surrounding villages were carried out by using Solid-state nuclear track detectors (LR-115 type II) in a bare mode. The detectors were distributed over 32 houses. The indoor radon concentration was found to vary with building material, ventilation condition, occupant's behaviour and mode of constructions of houses. The radon value was found to be lower than recommended value under normal ventilation condition. The indoor radon concentrations were found to vary from 30 Bqm-3 to 85.36Bqm-3 with an average value of 62.36 Bq/m3.This value is lower than the ICRP recommended values of 200Bqm-and thus are within safe limits. The outdoor radon concentration is usually low and less than average indoor levels. It is also found that, in general, the radon level in lower floors is higher than that in upper ones in all houses.
Key Words: Indoor radon concentration, SSNTD's, Annual Effective Dose, Uttar Pradesh, environment.

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Paper Type	:	Research Paper
Title	:	Design of OTA-C Active Low Pass Filter Using Multiple OTA's
Country	:	India
Authors	:	Rajeshwari S. Mathad, M. M. Mutsaddi, S. V. Halse
	:	10.9790/4861-0140812

Abstract: The studies are carried out on OTA-C active filter using single OTA-C and multiple OTA-C filter . The multiple OTA-C filters have the advantage of tuning the floating inductor resulting in enhancement of gain and increase in cut-off frequency with increase in bias current. Different cases of tuning transconductance gm1, gm1, gm , and gm2 by changing the bias currents of multiple OTA 's are studied and results are discussed. The only one method of setting of gm1 gm1 greater than gmgm2 is an innovative in changing the cut off frequency as we have flexible tuning transconductances of gm1, gm1, gm and gm2 . Results are consistent and are encouraging in respect of tuning of transconductance with bias current under the condition of gm1 gm1 greater than gmgm2 . However an OTA-C active filter other than the studied criteria has the limitations in designing of filters.
Keywords: OTA Operational Transconductance Amplifier OTA-C Operational Transconductance Amplifier – Capacitance

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