IR detector system based on high-Tc superconducting bolometer on Si membrane

摘要

Abstract: An infrared detector system based on high-T$-c$/ superconducting (HTS) membrane bolometer is reported. Superconducting transition-edge bolometer has been manufactured by silicon micromachining using an epitaxial GdBa$-2$/Cu$-3$/O$-7$MIN@x$/ film on an epitaxial yttria- stabilized zirconia buffer layer on silicon. The active area of the element is 0.85 $MUL 0.85 mm$+2$/. The membrane thickness is 1 $mu@m, those of the buffer layer and HTS films are 50 nm. The detectivity of bolometer, D$+*$/, is 3.8 $MUL 10$+9$/ cm Hz$+$HLF$/ W$+$MIN@1$/ at 84.5 K and within the frequency regime 100 $LS f $LS 300 Hz. The optical response is 580 V/W at time constant 0.4 ms. This is one of the fastest composite type HTS-bolometer ever reported. The bolometer is mounted on a metal N$-2$/-liquid cryostat, which fits the preamplifier. With the volume of N$-2$/-reservoir being 0.1 liter, the cryostat holds nitrogen for about 8 hours. Using only wire heater with constant current, the temperature stability of about 0.03 K/h is achieved. The detector system can be used in IR- Fourier spectroscopy at wavelengths longer than the typical operating range of semiconductor detectors (wavelength greater than about 20 $mu@m).!12