Patent ID: 6756316
Filing Date: 2004-06-29
Classification: B81B,B81C,G01L

Abstract:
A method for making an air capacitive hole for pressure transducer structure, the air capacitive hole lying between a bottom metallization feature and a top metallization feature, the system for making the air capacitive hole comprising:a plasma etcher for plasma etching a bottom metallization layer to form the bottom metallization feature that is not in electrical contact with a substrate; a deposition chamber for depositing a dielectric layer over the bottom metallization feature, the dielectric layer having a tungsten plug that is in contact with the bottom metallization feature; the plasma etcher being configured to etch a top metallization layer to form a top metallization feature that substantially overlies the tungsten plug, but leaves an opening down to the tungsten plug; and a bath for submersing the pressure transducer structure into a basic solution, such that the tungsten plug comes in direct contact with the basic solution and causes the tungsten plug to erode and define the air capacitive hole.