J. ChenX. ChengI-M. ShenJ.-H. LiuPAI-CHI LIM. Wang2018-09-102018-09-102007-1010577157http://scholars.lib.ntu.edu.tw/handle/123456789/334060https://www.scopus.com/inward/record.uri?eid=2-s2.0-34948862204&doi=10.1109%2fJMEMS.2007.902449&partnerID=40&md5=c3735f604f3d4b6ff78aee6f20d4621fThis paper presents the first monolithic multidirection-looking ultrasonic imager for minimally invasive medical diagnosis. In contrast to the traditional planar ultrasonic imagers that can only view in one direction, this 3-D array is able to view in multiple directions by using seven planar imagers integrated on a hexagonal silicon prism. Each facet on the prism is integrated with a planar 1- or 2-D capacitive-micromachined ultrasonic-transducer imager array for viewing in a specific direction. Each facet is connected by a flexible dielectric membrane, which is monolithically fabricated with the transducers. The dielectric membranes also support the thin-film electrical interconnects between the arrays on different facets. The substrate is folded into a hexagonal prism after completion of the transducer microfabrication process. With this architecture, a one flip-chip bonded or monolithically integrated front-end electronic circuit will be able to manage all the imagers on the 3-D array. The number of bonding wires for a connection to external electronics can therefore be reduced. Imager prisms, which are ranging from 1 to 4 mm in diameter and 2 to 4 mm in length, and positioned to view in seven directions, have been prototyped. Preliminary testing shows that the imager transducers behaved consistently before and after the assembly process. Applications of this 3-D imager array include capsule ultrasound endoscope, intravascular ultrasound, and other internal imaging needs. © 2007 IEEE.Acoustic transducersFlip chip devices; Microfabrication; Monolithic integrated circuits; Ultrasonic imaging; Ultrasonic transducers; Dielectric membranes; Imager prisms; Transducer microfabrication; Medical imagingjournal article10.1109/JMEMS.2007.9024492-s2.0-34948862204WOS:000250068400003