The fundamental study of polyvinylidene fluoride (PVDF) and its application in a pyroelectric IR sensor device

The object of this research project was to find fabrication methods of pyroelectric devices for an infrared sensor using poly(vinylidene fluoride) (PVDF) polymer thin films. It is anticipated that such sensors will lead to IR cameras with improved sensitivity and reduced production costs compared to currently available technology. This concept had originated in collaboration with Teltron Technologies, Inc., a display manufacturing company in Pennsylvania. In order to succeed with the predicted polymer application a profound general research study on PVDF was undertaken. Initially the work focused on the preparation of PVDF thin polymer films. Solution deposition from an acetone/N,N-dimethylformamide (DMF) polymer solution was used to manufacture polymer thin films. The influences of the PVDF dissolving temperature and the DMF solvent concentration on the polymer\u27s surface morphology are described. The research project also includes an extensive study of the effect of the relative humidity and solution phase water on the polymer\u27s surface morphology and crystalline modification. For this purpose, a fast, nondestructive and reliable method was developed using IR spectroscopy to quantitatively determine the thickness and the crystalline phase composition in PVDF thin films. Finally, an annealing study of PVDF thin films was performed to determine how thermal treatment effects the polymer\u27s crystalline modification as well as the ordering of crystalline domains. The application of pyroelectric PVDF thin films in IR sensors shows promising results. The assembling technique of the electroactive target used in the sensors turned out to be of significant importance for good ferroelectric response