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:
Oct. 29, 2002
Filed:
Nov. 21, 2000
Yasuhiko Sugiyama, Chiba, JP;
Masamichi Oi, Chiba, JP;
Seiko Instruments Inc., , JP;
Abstract
A liquid metal ion source has an emitter electrode for emitting ions, an extraction electrode, proximate the emitter electrode for generating a focused electric field at a tip of the emitter electrode, and a suppression electrode proximate the extraction electrode for adjusting the strength of the focused electric field generated at the tip of the emitter electrode so that metal ions are extracted from liquid metal covering the tip of the emitter electrode at a desired emission current value. A storage device stores a function defining a relationship between variation (&Dgr;Ie) in current of the emitter electrode and variation (&Dgr;Vsup) in voltage of the suppression electrode as a function &Dgr;Ie=F(&Dgr;Vsup), with the voltage (Vext) of the extraction electrode being at a fixed value. A control apparatus controls voltages of the extraction and suppression electrodes and the emission current, detects the variation &Dgr;Vsup in the voltage (Vsup) of the suppression electrode when a voltage (Vext) of the extraction electrode is made to vary by only &Dgr;Vext with the current of the emitter electrode being held to a fixed value, and calculates flow impedance &Dgr;Vext/&Dgr;Ie using the voltage variation amounts &Dgr;Vext and &Dgr;Vsup and the function acquired form the storage device.