화학공학소재연구정보센터
학회 한국재료학회
학술대회 2016년 가을 (11/16 ~ 11/18, 경주 현대호텔)
권호 22권 2호
발표분야 A. 전자/반도체 재료 분과
제목 Individual piezoelectricity of component layers in ferroelectric/semiconducting superlattice
초록 Ferroelectric/semiconducting superlattice has been shown versatile change of functional properties different from bulk ferroelectric material. Interaction between ferroelectric polarization and semiconductor charge carrier at interface of each component layer affects to functional properties of superlattice. However, contribution of semiconducting layer to electromechanical properties to ferroelectric/semiconducting superlattice has not been fully understood yet. In this study, we performed time resolved x-ray microdiffraction experiment while applying external electric field. We could resolve the contribution of each component layer to piezoelectricity of ferroelectric/semiconducting superlattice.

A 400 nm-thick superlattice film consisting of 30 periods of the BiFeO3 (12.8 nm)/La0.75Ce0.25MnO3 (0.2 nm) repeating unit was deposited on top of 50 nm-thick La0.7Sr0.3MnO3 bottom electrode layer grown on (001)-oriented SrTiO3 substrate using a pulsed laser deposition technique. Pt top electrodes with a diameter of 100 um were deposited to form capacitor structure. The piezoelectric response was investigated using time-resolved x-ray microdiffrction in combination with triangular voltage pulses with maximum voltage of +20 V. The overall piezoelectric coefficient of superlattice was around 35 pm/V. The individual piezoelectric coefficient of each component layer will be discussed based on computational simulation using the intensity of superlattice diffraction.
저자 Seung Hyun Hwang1, Hyeon Jun Lee2, Jeong Hun Kwak1, Sejun Yoon2, Sanghan Lee1, Ji Young Jo2
소속 1School of Materials Science and Engineering, 2Gwangju Institute of Science and Technology
키워드 <P>superlattice; x ray diffraction; BiFeO<SUB>3</SUB>; piezoelectricity</P>
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