Revised proposal Nano-composite Matching Layer

Huang, Yuhong

Abstract

? The goal of proposed research is to develop a novel matching materials based on nano-composite materials and to develop spin-on coating process to facilitate fabrication of precisely controlled matching layer. Current technology for making matching layer is difficult in the control of thickness and thus the uniformity of thickness. An increase of acoustic loss was often observed in the system from the adhesion of a matching layer to the transducer. These problems will be much more severe for high frequency ultrasound transducers. In this proposed research, Chemat is planning to develop organic/inorganic hybrid nano-composite Sol-gel system matching materials and coating techniques to overcome these disadvantages of current matching layer technology. Due to nanostructure of the coating, matching layer with extreme low attenuation and wide range of impedance can be achieved. Using this hybrid Sol-gel coating process, uniform coating with thickness varying from submicron to 100 micron can be easily deposited at low temperature. Coating process provides better interface between transducer and matching layer than adhesive bonding process. This eliminates the loss due to the interface defects. In our previous work, Chemat has successfully developed technology for the fabrication of nanosized crystalline powder, its colloidal solution and spin-on process. By working closely with one of the leading research laboratory on diagnostic ultrasonic transducer research lead by Prof. K. Kirk Shung at the Department of Biomedical Engineering, University of Southern California, modeling of the effect of the matching layers developed under this effort on transducer performance will be conducted. The matching layer developed will be incorporated into the fabrication of transducers and tested. Success of this research will result in a new generation of matching layer materials which are easier to fabricate. ? ?