The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 04, 2000
Filed:
Jul. 01, 1998
Nai-Cheng Lu, Hsin-Chu, TW;
Taiwan Semiconductor Manufacturing Company, Hsin-Chu, TW;
Abstract
A micro vacuum tube is described. The process for manufacturing it begins with the deposition of two layers of polysilicon or metal, separated by dielectric layers, topping them with a layer of silicon nitride, and forming these into the shape of a disk. A hole is etched in the silicon nitride and then lined with a spacer, causing the width of the hole to decrease from top to bottom. When the hole is partially filled with a sacrificial layer the latter has a depression at its center which may be used as a mold for a microtip. To allow for easy removal of the sacrificial layer, pole holes are etched in it. These become support poles after the microtip material has been deposited over the sacrificial layer (which gets removed in its entirety). As an alternative to a microtip, a micro razor edge may be used for the cold emitter. A cap deposited over the structure while it is in vacuo serves to keep it under permanent vacuum.