公开(公告)号：US20170291192A1

公开(公告)日：2017-10-12

申请号：US15513588

申请日：2015-04-21

Applicant: Hitachi, Ltd.

Inventor： Shuntaro MACHIDA ,  Daisuke RYUZAKI ,  Tatsuya NAGATA ,  Naoaki YAMASHITA ,  Yuko HANAOKA ,  Yasuhiro YOSHIMURA

IPC: B06B1/06

CPC classification number: B06B1/06 ,  A61B8/4461 ,  A61B8/4494 ,  B06B1/0292 ,  B06B1/0607 ,  B06B1/0644 ,  G01N29/043 ,  G01N29/24 ,  G01N29/2406 ,  G01N2291/0232 ,  G01N2291/106 ,  H04R19/005 ,  H04R31/00

Abstract: A structure that prevents a substrate from being warped is provided on a region or a location other than a membrane that determines the characteristics of a CMUT. In a CMUT in a structure in which a first conductive layer and a second conductive layer are provided sandwiching a cavity on a substrate, for example, as a warpage prevention structure, a warpage prevention layer that prevents the substrate from being warped is provided between the substrate and the first conductive film. When the insulating film disposed between the cavity and the first conductive film and the insulating film disposed between the cavity and the second conductive film are silicon oxide films, the warpage prevention layer includes a silicon nitride film.