Domain Engineered Magnetoelectric Thin Films for High Sensitivity Resonant Magnetic Field Sensors
Abstract
Sol-gel deposition and RF sputtering process was developed for deposition of PZT on Pt/Ti/Si02/Si (hereafter, referred to as platinized Si) substrates. Target preparation was perfected for Zr/Ti ratios of 60/40 and 52/48 with excess Pb to compensate for Pb loss during post deposition annealing. As deposited PZT RF (henceforth, RF refers to "RF sputtering" in this report) thin films were not well textured (i.e. with preferred crystalline orientation). To texture and obtain crack-free thick PZT RF films, we employed pretreated substrates and post-deposition annealing. One pre-treatment was the use of seed layer of textured PZT sol-gel thin film of thickness 65-85nm. A detailed study was conducted to determine the conditions for obtaining preferred crystallite orientations (referred as textured). The results of this study were summarized in Temperature-Time-Transformation (TTT) diagrams. These diagrams provide two-dimensional relationships of crystalline orientation to pyrolysis and annealing conditions. To augment our understanding of the thermal budgets required for the texturing of the PZT sol-gel thin films, we further developed relationships between each phase and the experimental conditions. In addition, the optical band gap, morphology and composition of highly textured sol-gel thin films were evaluated using Variable Angle Spectroscopic Ellipsometry (VASE), Raman scattering, piezoresponse force microscopy (PFM) and X-ray photoelectron spectroscopy (XPS). RF sputter deposition operating space was explored using statistically designed experiments (using Design Expert software) and ANOVA (Analysis of Variance) models were formulated. The responses were thickness, refractive index and absorption coefficient from ellipsometric data and the elemental compositions from energy dispersive X-ray analysis of the PZT thin films. These models were then utilized to predict and optimize the process conditions necessary to obtain the preferred responses.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 2011
- Accession Number
- AD1010726
Entities
People
- Shashank Priya