Electron beam measuring instrument
Patent 4963823 Issued on October 16, 1990. Estimated Expiration Date: 
May 9, 2009. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
May 9, 2009. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesCorpuscular beam microscope for ring segment focusing Electron beam integrated circuit tester Patent #: 4779046 InventorsAssigneeApplicationNo. 349432 filed on 05/09/1989US Classes:324/751, Using electron beam probe250/311Electron microscope typeExaminersPrimary: Karlsen, Ernest F.Attorney, Agent or FirmInternational ClassG01R 031/28Foreign Application Priority Data1988-06-27 DEAbstractConventional beam blanking system generate electron pulses having a minimum width of about 100 through 200 ps. Although a reduction of the pulse width to a few tens of picoseconds is fundamentally possible, the reduction of the probe current accompanying this would result to a considerable lengthening of the measuring times. In the invention a photo-cathode (PK) is charged by a pulsed laser beam (LA) which is attached to the column of an electron beam measuring instrument and the photo-electron source is stigmatically imaged onto the beam axis (OA1) using a focusing deflection unit (SFM). A sector field magnet is used as a focusing deflection unit (SFM). | |
