Uncooled bolometer based on Mn1.56Co0.96Ni0.48O4 thin films for infrared detection and thermal imaging

Abstract

Polycrystalline films of Mn1.56Co0.96Ni0.48O4 (MCN) were evaluated for uncooled bolometric applications grown by chemical solution deposition on amorphous Al2O3 substrate. The microstructural characterizations showed that the films were of excellent crystallization and compact surface morphology. Electrical results showed that the temperature coefficient of resistance reached −3.8%/K at 295 K. Low excess noise (normalized Hooge parameter αH/n of 7.6 × 10−28 m3) was achieved owing to the good epitaxial quality of the prepared films. Infrared bolometers were fabricated to evaluate the performance on infrared detection. It exhibited a noise equivalent temperature as low as 2.1 × 10−7 K/Hz1/2, responsivity of 330 V/W, detectivity of 0.6 × 108 cm Hz1/2/W, and noise equivalent power of 3.7 × 10−10 W/Hz1/2 at 30 Hz. The feasibility of the MCN films was demonstrated to be used for uncooled bolometric applications by thermal imaging. One can expect to get a responsivity of about 1 × 103 V/W and detectivity higher than 6 × 108 cm Hz1/2/W at 30 Hz for thermally isolated MCN film bolometer. The results of MCN showed its great potentiality for future room-temperature detection.