STRONG PYROELECTRIC RESPONSE IN SEMICONDUCTING Y-BA-CU-O AND ITS APPLICATION TO UNCOOLED INFRARED DETECTION

A pyroelectric infrared detector operating at room temperature and bas ed on semiconducting Y-Ba-Cu-O was fabricated. The capacitor structure consisting of semiconducting Y-Ba-Cu-O layer sandwiched between two N b electrodes was fabricated on top of a thermally isolated SiO2 bridge . The polycrystalline Y-Ba-Cu-O layer was deposited by ambient-tempera ture sputtering while standard Si micromachining techniques were used to etch the silicon under the oxide bridge. The pyroelectric response of the material is characterized by the temperature coefficient of pol arization (p=dP/dT) which was measured to be as high as 65 nC/K cm(2) without an externally applied electric field. The pyroelectric figure of merit F-d for the material was estimated to be 0.032 (cm(3)/J)(1/2) . Employing a radiometric infrared source, the room-temperature voltag e responsivity R-V and specific detectivity D of the unbiased detecto r were measured to be over 10(3) V/W and 10(8) cm Hz(1/2)/W, respectiv ely. This letter discusses the characteristics of this complementary m etal-oxide semiconductor-compatible pyroelectric detector and suggests methods for the improvement for its figures of performance. (C) 1997 American Institute of Physics.