摘要
锆钛酸铅(PZT)是一种优良的铁电材料,具有耦合系数和压电系数大、居
里点高及可通过变更配比度和掺杂在很大范围内调整性能以满足多种不同需要
等优点。把PZT制成薄膜状,并保持其优良的电学特性,能大大缩小器件的体
积,提高器件的性能;此外,还能利用二维材料的特有性能,使PZT在传感器
等多方面的应用获得更广阔的前景。
本文以降低PZT薄膜退火温度,提高电学特性为目的,研究了RF溅射法制
取PZT铁电薄膜的制备工艺和电学特性。改进了靶材的制备工艺。比较了Au、
Ag、Pt三种底电极上PZT薄膜晶化成钙钛矿结构的退火温度和电学特性。对比
了锆钛配比度为30/70、53/47、70/30的PZT铁电薄膜各方面不同的特点。比较
了用预烧粉末、块状陶瓷作为靶在PZT铁电薄膜的制备中的不同情况。与此同
时,研究了真空蒸镀法制备Ag、Au、Pt三种底电极的制备工艺。
研究结果发现:用冷压、不加粘合剂成型的办法可以制备合格的PZT块状
靶材;用真空蒸镀法可以制取蒸发温度很高的Pt底电极,尽管薄膜淀积速率较
低;当Ag膜达到一定厚度时,可以解决Ag膜退火后球化带来的电极作用失效
的问题;相对于Au、Pt而言,Ag电极能有效降低PZT薄膜的晶化温度100-200
℃,Pt底电极能使PZT薄膜的电学性能达到最佳;配比度为30/70的情况下,薄
膜的淀积速率最大,完全晶化成钙钛矿结构所需的退火温度最低。与块状靶相比,
用预烧粉末靶制取的薄膜能有效地降低晶化温度达200℃,但对于预烧粉末靶,
薄膜的淀积速率较低。
Pb(Zr,Ti)Os (PZT) is a kind of ferroelectric materials, which
eXhibits high value of dielectfic constant, spofltaneous polariZtion ps,
moduli dij of piezoelectricity and electromechanical couPling
coefficient .If the electric properties of PZT ferroelectric can be kept
When PZT is made in the form of thin film,we can downsize the
electronic components and PZT thin films will be used extensively in
many aPplications (e.g. actuators, sensors ).
This paPer investigates the fabricating process and electric
properties of PZT thin films deposited by r. f sputtering for the purpose
of decreasing the annealing temperature and improving the electric
properties. The whole work includes f improving fabricating technique of
target; investigating different annealing temperature and electfic
properties of PZT thin film on the condition that the films are deposited
on the three kinds of electrode (incIuding Ag, Au, Pt) and on the
condition that the Zr:Ti concefltration ratios are
different(30f70,53 f47,70f30) and on the condition thdt the ceramics target
is changed into powder target, investigating fabricating technique of
bottom electrodes (including Ag, An, Pt) formed by evaPoraton.
The result indicates f PZT target can be fabricated not using the
method of hot-press and not adding bond, Pt electrode can be made by
evaporation, the annealing temperature of PZT thin film on Ag electrode
is lower than on Au and on Pt electrode, when the Zr;Ti concefltfation
ratio is 30f70, the crystal temperature is the lowest, PZT thin film made
by powder target can decrease the annealing temPerthee effectively.
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