DEVELOPMENT OF SMART NANO-SENSORS BY HYBRID INTEGRATION OF CSD-DERIVED THIN FILMS

锆钛酸铅（PZT）薄膜在探索其潜在性质[1-3]或其在准同型相界（MPB）附近的优异介电、铁电和压电性质的起源[4-6]方面吸引了全世界的兴趣。PZT薄膜具有上级的铁电、热释电、压电和电子发射等特性，有望应用于存储器件、微电子机械系统（MEMS）和显示器等领域，本文通过控制前驱体、晶种层和薄膜中的残余应力等因素，影响CSD制备的PZT薄膜电学性能的其他因素包括薄膜成分、薄膜电极和薄膜中的残余应力，而残余应力的大小主要取决于包括薄膜电极的衬底、退火工艺以及薄膜厚度。如果使用分子设计的前体溶液，则膜组成易于控制。本论文主要制备了组成接近准同型相界的PZT前驱体溶液（MPB ; Pb：Zr：Ti = 120：53：47），并采用Pt/Ti/SiO_2/Si作为衬底，因为衬底与半导体材料相容。因此，我们在本文中关注的最后一个重要因素是薄膜中的残余应力，因为铁电性和压电性应该受到薄膜中的残余应力的强烈影响，而薄膜中的残余应力受到薄膜加工的强烈影响。

Lead zirconate titanate (PZT) thin films have been attracting worldwide interests in exploring their potential properties [1-3] or the origins [4-6] of their excellent dielectic, ferroelectric and piezoelectric properties near the morphotropic phase boundary (MPB). PZT thin films are expected to apply to the memory devices, micro electro mechanical systems (MEMS), and display because of their superior ferroelectric, pyroelectric, piezoelectric and electron emission properties.In this study, high-performance piezoelectric PZT thin films for actuated mirror array and optical scanner were developed by controlling the several factors, such as molecular-designed precursor, seeding layer and the residual stress in films, by a chemical solution deposition (CSD).The other factors that affect the electrical properties of the CSD-derived PZT thin films are composition, thin film electrode and the residual stress in the resultant films which strongly depends on the substrate including thin film electrode and the annealing processes as well as the film thickness. The film composition is easy to control if the molecular-designed precursor solution is used. In this paper, we mainly prepared PZT precursor solution with a composition near morphotropic phase boundary (MPB ; Pb : Zr : Ti = 120:53:47) and used Pt/Ti/SiO_2/Si substrate because of the compatibility with the semiconductor. Therefore, the last important factor we focused in this paper is the residual stress in the films because ferroelectricity and piezoelectricity should be strongly affected by the residual stress in the films which is strongly affected by the thin film processing.