The ability to fabricate Capacitive Micromachined Ultrasonic Transducers (cMUTs) and signal conditioning electronics together on the same silicon substrate offers significant benefits to overall transducer performance, and simplifies connectivity within a dense 2D transducer array. This integration of cMUTs and electronics has been demonstrated utilising a lowtemperature silicon nitride membrane technology, postprocessed onto CMOS-ASIC substrates. Successful results from fabricated arrays of cMUTs and front-end analogue amplifiers confirm the integration to be relatively simple and highly manufacturable. optimum method of integrating transducers and electronics on the same substrate. This paper presents the fabrication of cMUTs using a low-temperature silicon nitride membrane technology, thus enabling transducers to be fabricated directly onto a silicon substrate containing prefabricated electronics. This results in an inherent lowparasitic connectivity to individual transducer elements within an array, whilst retaining full flexibility in controlling the fundamental device properties which determine the transducers' subsequent acoustical performance.

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