P4M-2 A Linear CMUT Air-Coupled Array For NDE Based on MUMPS

In this paper, the design and characterization of a linear cMUT array based on MUMPS technology is presented. The array has 33 elements having each element 68times2 cMUT cells electrically connected in parallel. The single cell consists of a 130 mum square shaped polysilicon membrane, a gold top electrode, silicon nitride as the isolation layer between conductors and heavily doped silicon which works as the bottom electrode. The central frequency is 720 kHz. Electrical and optical measurements were performed and compared with FEM calculations. These results were used to study the mechanical and electrical behaviour of the device.