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:
Feb. 19, 2002
Filed:
Aug. 10, 1999
Yoshihiro Hirota, Kyoto, JP;
Toshiyuki Matsumoto, Hyogo-ken, JP;
Sumitomo Metal Industries Limited, Osaka, JP;
Abstract
There is provided a probing and measurement system for measuring a capacitance value of a capacitance to be measured, by removing any influence made by a parasitic capacitance and a fluctuation thereof within a shield box . The probing and measurement system comprises a prober , a signal line having one end to be in contact with a sample to be measured, a shield line surrounding the signal line, and a capacitance measurement circuit . The capacitance measurement circuit comprises an operational amplifier having an inverting input terminal connected to the other end of the signal line and a non-inverting input terminal connected to the shield line, wherein an imaginary short state exists between the inverting input terminal and the non-inverting input terminal, and wherein a signal having a value corresponding to an electrostatic capacitance of the sample to be measured is outputted when an AC signal is applied to the non-inverting input terminal. Conductive portions of the shield box , conductive portions of a stand , a surface of the stand which contacts with the sample to be measured, and the shield line are placed at the same electric potential.