Temperature-Dependent Resistive Properties of Vanadium Pentoxide/Vanadium Multi-Layer Thin Films for Microbolometer & Antenna-Coupled Microbolometer Applications

Abstract

In this study, vanadium oxide (VxOy) semiconducting resistive thermometer thin films were developed, and their temperature-dependent resistive behavior was examined. Multilayers of 5-nm-thick vanadium pentoxide (V2O5) and 5-nm-thick vanadium (V) films were alternately sputter-deposited, at room temperature, to form 105-nm-thick VxOy films, which were post-deposition annealed at 300 °C in O2 and N2 atmospheres for 30 and 40 min. The synthesized VxOy thin films were then patterned into resistive thermometer structures, and their resistance versus temperature (R-T) characteristics were measured. Samples annealed in O2 achieved temperature coefficients of resistance (TCRs) of −3.0036 and −2.4964%/K at resistivity values of 0.01477 and 0.00819 Ω·cm, respectively. Samples annealed in N2 achieved TCRs of −3.18 and −1.1181%/K at resistivity values of 0.04718 and 0.002527 Ω·cm, respectively. The developed thermometer thin films had TCR/resistivity properties suitable for microbolometer and antenna-coupled microbolometer applications. The employed multilayer synthesis technique was shown to be effective in tuning the TCR/resistivity properties of the thin films by varying the annealing conditions.

Semiconducting Carbon Nanotubes Embedded in a Metallic Film for a Thermistor Device with an Adjustable Temperature Coefficient and Reduced Noise Source Activities

“…For instance, our hybrid film with sSWCNTs and 10 nm thick Au film had a resistivity of 4.73 × 10 −6 Ω cm, while that of vanadium oxide, which has been extensively used in negative temperature coefficient thermistors, is usually larger than 10 −1 Ω cm. [ 29–31 ]…”

“…For instance, our hybrid film with sSWCNTs and 10 nm thick Au film had a resistivity of 4.73 × 10 −6 Ω cm, while that of vanadium oxide, which has been extensively used in negative temperature coefficient thermistors, is usually larger than 10 −1 Ω cm. [29][30][31] Since our system included an fast Fourier transform network analyzer (SR770, Stanford Research Systems), we could place a conducting AFM probe on a specific location of our sample surface to measure the noise spectra. Figure 4e shows the graph of the current-normalized power spectral density (PSD) versus frequency f, which was measured at two different positions: i) Au region and ii) sSWCNT/Au region.…”

Electro-Optical Characterization of Amorphous Germanium-Tin (Ge1-XSnx) Microbolometer

“…Two main temperature sensing mechanisms are employed in commercial microbolometers: silicon on insulator (SOI) diode-based [2] and resistive-based [3] sensing. In SOI diode-based sensing, the wellknown dependency of the pn junction diode's saturation current on temperature is utilized for temperature sensing [4].…”

Amorphous SiSn Alloy: Another Candidate Material for Temperature Sensing Layers in Uncooled Microbolometers

“…Various materials have been utilized as active temperature sensing layers in microbolometers. These materials include thin films made of vanadium oxide (VO x ) (1.1-4% K À1 ), [8][9][10][11][12][13][14][15][16][17] hydrogenated amorphous Herein, the prospect of using amorphous Si 1-x Sn x alloys as alternative temperature-sensing active materials in microbolometers is evaluated by studying their temperature-dependent resistive properties along with their infrared optical properties. Si 1-x Sn x thin films (200 nm thick), with varying Sn concentrations, are prepared at room temperature by cosputtering from Si and Sn targets using simultaneous radio frequency and DC magnetron sputter deposition.…”

“…Various materials have been utilized as active temperature sensing layers in microbolometers. These materials include thin films made of vanadium oxide (VO x ) (1.1–4% K −1 ), [ 8–17 ] hydrogenated amorphous silicon (a‐Si:H) (2–5% K −1 ), [ 18–20 ] silicon germanium (Si x Ge 1– x ) (≈4.5% K −1 ), [ 21,22 ] germanium tin (Ge 1– x Sn x ) (≈4% K −1 ), [ 23 ] amorphous germanium silicon oxide (Ge x Si y O 1– x – y ) (≈5% K −1 ), [ 24 ] and semiconducting phase of yttrium barium copper oxide (YaBaCuO) (2.5–4% K −1 ), [ 25 ] and others have exhibited high TCR values and have been explored as temperature sensing layers in microbolometers.…”