The big and small CMUTs are designed to have a center frequency of 3 MHz and 30 MHz respectively, a bandwidth of 100 % and a coupling coefficient of 0.5. The CMUT array contains an infinite number of elements, each consisting of Digital Object Identifier: 10.1109/ULTSYM.2008.0520 Keywords; CMUT, receive amplifiers, neighbor coupling Figure 1. Illustration of the CMUT design. Membrane stack: 200 nm PECVD Si 3 N 4 30 nm Aluminum 100 nm LPCVD Si 3 N 4 60 nm cavity depth Silicon substrate μ μ m