High Tc superconducting thin film YBa2Cu3O7-δ (YBCO) bolometers have been fabricated on various substrates such as MgO, LaAlO3, YSZ and Si using laser ablation technique. Performance of these IR bolometers operating with a Joule-Thomson refrigerator has been investigated. Measurements of the responsivity and low frequency noise near Tc in the current biased YBCO bolometers show that reliable devices can be fabricated. Measured noise equivalent power (NEP), for YBCO/YSZ bolometer, reaches 6 × 10-10W/Hz 1 2 at 165 Hz and has a responsivity of 60 V/W with a blackbody source. This performance is comparable to that of the optimized pyroelectric detectors. The characteristics of YBCO films deposited on Si substrates reveal that superconducting thin film multi-elements or focal plane array with silicon integrated readout circuit are feasible. Such bolometers exhibit NEP of 7 × 10-9W/Hz 1 2, and significant improvement appears possible. Electrical measurements show no noticeable film degradation after the bolometer is exposed to atmosphere for three months.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics