Performance evaluation of a lead-titanate (PbTiO3) pyroelectric thin-film infrared sensor with temperature isolation improvement structure by microelectromechanical system (MEMS) technologies

Abstract

An IR sensor with the lead-titanate thin-film using the technology of micro-electro-mechanical systems to achieve a better thermal isolation structure has been fabricated and developed. The major IR-sensing part on the cantilever beam with dimensions of 200 X 100 X 2 micrometers <SUP>3</SUP> consists of a 500-angstrom lead-titanate layer deposited by RF sputtering, and an evaporated bismuth layer. This thermal isolation improved structure exhibits a much superior performance to that of a traditional IR-sensing bulk structure on the experimental results, which show a 200 percent and 300 percent improvement in current gain under the incident optical power 500 (mu) W and 6V applied bias at room temperature and 77 degrees K, respectively.