Barium strontium titanate(BST) is a pyroelectric material. So it can be used for infrared detector material. In this thesis, BST capacitors are made, and their electrical characteristics and thermal characteristics are measured.
$Ba_0.67$ $Sr_0.33$ $TiO_3$ thin films for uncooled infrared detector are deposited on the bottom electrode(Pt, Ir) by both RF-sputtering and spin-coating. Films deposited by RF-sputtering have better electrical characteristics than those deposited by spin-coating. In case of sputtered films Thermal coefficient of dielectric constants(TCD) are about 0.1%/℃ and in case of spin-coated films TCDs are 0.2%/℃. But they are too small to use pyroelectric material for infrared detectors.
Grain sizes of BST must be larger than 0.12㎛ for BST films to have pyroelectric characteristics. But those in this thesis are about 0.026㎛, so they have poor thermal characteristics.
To overcome this problem, a new deposition method is suggested. After a sputtered BST deposition which has good crystallity, a spin-coated BST which has large grains is deposited. It is expected that BST films which have good crystallity and large grains can be deposited.
