Diodes As Ionizing Radiation Detectors and Temperature Measurements

Exploring the Characteristics of Diodes as Radiation Detectors and Temperature Sensors

by Remya Balakrishnan*, Dr. Radhey Shyam Jha,

- Published in Journal of Advances in Science and Technology, E-ISSN: 2230-9659

Volume 3, Issue No. 6, Aug 2012, Pages 0 - 0 (0)

Published by: Ignited Minds Journals

ABSTRACT

Fromthe Shockley ideal diode equation it might appear that the voltage has a positive temperature coefficient (at a constant current),but usually the variation of thereverse saturation current term is moresignificant than the variation in the thermal voltage term. Most diodestherefore have a negative temperaturecoefficient, typically −2 mV/˚C for silicon diodes at room temperature. This isapproximately linear for temperatures above about 20 kelvins. Some graphsare given for: 1N400x series, and CY7 cryogenic temperaturesensor. In electronics, cosmic rays and other sources ofionizing radiation cause noise pulses and single and multiple biterrors. This effect is sometimes exploited by particle detectors todetect radiation. A single particle of radiation, with thousands or millions ofelectron volts of energy, generates many charge carrier pairs, as itsenergy is deposited in the semiconductor material. If the depletion layer islarge enough to catch the whole shower or to stop a heavy particle, a fairlyaccurate measurement of the particle's energy can be made, simply by measuringthe charge conducted and without the complexity of a magnetic spectrometer,etc. These semiconductor radiation detectors need efficient and uniform chargecollection and low leakage current

KEYWORD

diodes, ionizing radiation detectors, temperature measurements, Shockley ideal diode equation, voltage coefficient, reverse saturation current, thermal voltage term, negative temperature coefficient, silicon diodes, room temperature, linear, 20 kelvins, 1N400x series, CY7 cryogenic temperature sensor, electronics, cosmic rays, noise pulses, bit errors, particle detectors, charge carrier pairs, depletion layer, particle's energy, semiconductor material, efficient charge collection, low leakage current