Great Enhancement Of Pyroelectric Properties For Ba_(0.65)sr_(0.35)tio_3 Films On Pt-si Substrates By Inserting A Self-buffered Layer

摘要

(100)-Ba_(0.65)Sr_(0.35)TiO_3 (BST) films were deposited on Pt/Ti/SiO_2/Si substrates using a low-temperature self-buffered layer. X-ray diffraction and atomic force microscope investigations show that the microstructure of BST films strongly depends on surface morphology of annealed self-buffered layer. The mechanism of nucleus formation and the growth initiation of BST films on self-buffered layers were proposed. It was found that the pyroelectric properties of BST films can be greatly enhanced. The pyroelectric coefficient and material merit figure of (100)-BST films are 1.16×10~4 μC m~(-2) K~(-1) and 2.18 ×10~(-4) Pa~(-1/2), respectively. The detectivity of 9.4 × 10~7 cm Hz~(1/2) W~(-1) was obtained in the (100)-BST film capacitors thermally isolated by 500 nm SiO_2 films.