THICKNESS-DEPENDENCE OF RESIDUAL STRESS IN LEAD-FREE FERROELECTRIC K_(0.5)Na_(0.5)NbO_(3) FILMS  

作　　者：LINGYAN WANG WEI REN PHOI CHIN GOH KUI YAO PENG SHI XIAOQING WU 

机构地区：[1]Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education and International Center for Dielectric Research Xi'an Jiaotong University,Xi'an 710049,P.R.China [2]Institute of Materials Research and Engineering A*STAR(Agency for Science,Technology and Research)3 Research Link,Singapore 117602

出　　处：《Journal of Advanced Dielectrics》2012年第4期55-61,共7页先进电介质学报（英文）

基　　金：the support from the Natural Science Foundation of China(Grant No.90923001);the International Science and Technology Cooperation Program of China(Grant Nos.2010DFB13640 and 2011DFA51880);the Shaanxi Province International Collaboration Program(Grant Nos.2009KW-12 and 2010KW-09);the Fundamental Research Funds for the Central Universities(Grant No.0105-08143078);supported by the research grant,SERC of A*STAR(Agency for Science,Technology and Research),Singapore(No.0921150112)。

摘　　要：Lead-free ferroelectric K_(0.5)Na_(0.5)NbO_(3)(KNN)films with different thicknesses were prepared by polyvinlypyrrolidone(PVP)-modified chemical solution deposition(CSD)method.Their residual stresses were studied with two methods of X-ray diffraction(XRD)and nanoindentation fracture.It was found that the tensile stress occurs in KNN films with small thickness of 1.3μm after all kinds of stresses were neutralized,which is mainly originated from the interaction across grain boundaries.With increasing the thickness to 2.5μm and above it,the residual stress changed from tensile stresses to compressive stresses,and the compressive stress decreased with the thickness increased.These results could explain why a thicker KNN film can show improved electrical properties and the larger the thickness,the better the ferroelectric and piezoelectric properties.

关 键 词：K_(0.5)Na_(0.5)NbO_(3)films different thicknesses residual stresses XRD method nanoindentation fracture method 

分 类 号：TG1[金属学及工艺—金属学]