公开(公告)号：EP0983609A1

公开(公告)日：2000-03-08

申请号：EP98925745.6

申请日：1998-05-19

Applicant: THOMSON-CSF SEXTANT

Inventor： LEFORT, OlivierThomson-CSF Protection & Conseil ,  THOMAS, IsabelleThomson-CSF Protection & Conseil

IPC: H01L21/00 ,  G01P15/08

CPC classification number: B81C1/0015 ,  B81B2201/0235 ,  B81C2201/053 ,  G01P15/0802 ,  G01P15/125

Abstract: The invention concerns the production of machined silicon micro-sensors, in particular accelerometers for assistance to navigation in aircraft, and pressure sensors. In order to improve the production of certain active parts of the sensor, and particularly of a beam (32) forming a resonator, whereof the width and thickness characteristics should be well controlled, the method consists in: producing, by micro-machining the silicon on a first plate (30), a beam with thickness equal to the required final thickness, said beam being coated on its top surface with a mask defining the required final width; assembling the plate (30) with another (10); oxidising the two surfaces of the beam to coat them with a thin protective layer; removing, by vertical directional etching, said thin protective layer on the top surface without removing the mask already there; working on the silicon in the zone exposed by the previous operation, using vertical directional etching on the top surface, until all the part of the beam not protected by the mask is eliminated thereby producing the beam with the required width.