Excess noise in YBa2Cu3O7 epitaxial films and antenna-type microbolometersbased on them

Monte Carlo modelled anneals of YBa2Cu3O7 epitaxial films have been carried out, and the excess flicker noise in the operating frequency and temperatu re ranges were shown to be dominated by oxygen migration near small-angle b lock boundaries. Optimization of film and planar-microstructure fabrication permitted reaching a record-low Hooge noise parameter (1.8x10(-4) at 93 K) for test structures, which can be used to prepare high-performance antenna -type strip microbolometers. Calculations show that the reduction of the mi crostrip size to 1x0.7 mu m(2) and of the flicker noise made possible detec tion of radiation within the spectral range from 3 mm to 300 mu m (100-1000 GHz) at 90 K, with a nanosecond response and a noise-equivalent power of 1 .5x10(-12) W/Hz(1/2) at frequencies from 30 to 10(7) Hz, which is close to the limitations imposed by phonon noise. (C) 1999 American Institute of Phy sics. [S1063-7834(99)00411-6].