<title>Comparative investigations of the bolometric properties of thin film structures based on vanadium dioxide and amorphous hydrated silicon</title>

Abstract

A choice of sensitive element material for uncooled microbolometric array dependents on the ultimate array parameters to a great extent. This paper presents the results of studies of sandwich and planar bolometric structures based on aSi:H and v02 films accordingly. The aSi:H films were fabricated by plasmachenucal vapor-phase deposition and V02 films were prepared by reactive magnetron ion-plasma sputtering. Sandwich structures with area lOOx 100 pm have a resistance of 20 kf and temperature coefficient of resistance (TCR) of 2°/1K at 25 °C. Planar structures with operating section dimensions of 100x70 tm have TCR of 2.9 %/( at the same resistance. The methods of contact noise reduction are found for both type structures. Sandwiches constructed to act as an optical cavity absorb 80% of radiation at 8 tm wavelength. It is shown that the planar structures absorption of 50-80% can be reached in the 8.5-10 tm band.

Bolometric characteristics of macroporous silicon structures

“…1/f noise is sizable at frequencies less than 10 Hz. Absolute noise values are (25)⋅10 -9 VHz -1/2 for frequencies exceeding 10 Hz, which is more than 10 times lower than the noise level in amorphous and α-Si [2,3]. 10 ms, voltage response of 10 3 V/K [1], and temperature coefficient of resistance of 1%, the detectivity of thermal bolometric elements based on macroporous silicon might be equal to 5⋅10 9 cmHz 1/2 W -1 .…”

“…The important characteristics required of microbolometric matrices are a high temperature coefficient of electrical resistance, low excess noise and good radiation absorption in the operation spectral region. The structures based on amorphous or polycrystalline silicon satisfy such requirements [2,3]. In this work, results of researches of macroporous silicon structures made by photoanodic etching are given.…”

Recent Developments in Wearable NEMS/MEMS-Based Smart Infrared Sensors for Healthcare Applications

“…As a result, combined phases of VO 2 and V 2 O 5 could show a practical resistivity that works with the readout electronics for very sensitive bolometers. 92 As the film's architecture is sensitive to the growing settings, VO x films must be grown cautiously. The two key development factors that regulate the constitution and particle size of the oxide films are typically the substrate temperature and oxygen pressure.…”

“…As a result, combined phases of VO 2 and V 2 O 5 could show a practical resistivity that works with the readout electronics for very sensitive bolometers . As the film’s architecture is sensitive to the growing settings, VO x films must be grown cautiously.…”

Group IV Materials for Low Cost and High Performance Bolometers

“…The typical phases are known as VO, V 2 O 3 , VO 2 (or V 2 O 4 ) and V 2 O 5 (or as a "mixed oxide) (Subrahmanyam et al, 2008 Thus, a mixed phase of VO 2 and V 2 O 5 may demonstrate an appropriate resistivity which is convenient and matches also with the readout electronics for high sensitive bolometers (Malyarov, 1999).…”