Patent · US Expired

Process for forming a buried cavity in a semiconductor material wafer and a buried cavity

US6693039B2 · kind B2 · utility

11Cited by
5References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 27, 2001
Grant dateFeb 17, 2004
Priority date
Expiry dateMay 19, 2021

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB81C1/00404
  • WIPO fieldMicro-structural and nano-technology
  • WIPO sectorChemistry

Abstract

The process comprises the steps of forming, on top of a semiconductor material wafer, a holed mask having a lattice structure and comprising a plurality of openings each having a substantially square shape and a side with an inclination of 45° with respect to the flat of the wafer; carrying out an anisotropic etch in TMAH of the wafer, using said holed mask, thus forming a cavity, the cross section of which has the shape of an upside-down isosceles trapezium; and carrying out a chemical vapor deposition using TEOS, thus forming a TEOS layer which completely closes the openings of the holed mask and defines a diaphragm overlying the cavity and on which a suspended integrated structure can subsequently be manufactured.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.