Patent assignee · JP · COMPANY

Hitachi Electronics Engineering Co., Ltd.

93Patents
2Active
93Granted
40Portfolio score

Filing activity: Nov 18, 1977 → Jun 13, 2008 · 2 expiring within 5 years

Most-cited patents

PatentTitleAreaCited byStatus
US5903342A Inspection method and device of wafer surface Physics 133 Expired
US6411377B1 Optical apparatus for defect and particle size inspection Electricity 92 Expired
US4614427A Automatic contaminants detection apparatus Physics 90 Expired
US6002989A System for quality control where inspection frequency of inspection apparatus is reset to minimize expected total loss based on derived frequency function and loss value Emerging Cross-Sectional Technologies 57 Expired
US6515470B2 Method and apparatus for testing IC device Performing Operations; Transporting 52 Expired
US5694214A Surface inspection method and apparatus Physics 51 Expired
US6366982B1 Raid library apparatus for transportable media and method of controlling the library apparatus Physics 48 Expired
US5290419A Fluorescence detection type electrophoresis apparatus Physics 44 Expired
US6275023A Semiconductor device tester and method for testing semiconductor device Physics 41 Expired
US4613573A Automatic bacterial colony transfer apparatus Emerging Cross-Sectional Technologies 40 Expired
US5245403A Apparatus for detecting extraneous substances on a glass plate Physics 39 Expired
US5092011A Disk washing apparatus Emerging Cross-Sectional Technologies 36 Expired
US5822139A Method of detecting thermal asperity error of MR head and magnetic disk certifier using the same method Physics 35 Expired
US4173073A Track displacement detecting and measuring system Performing Operations; Transporting 33 Expired
US6509966B2 Optical system for detecting surface defect and surface defect tester using the same Physics 33 Expired
US5014143A Data recording disk chuck mechanism Physics 31 Expired
US6617603B2 Surface defect tester Physics 31 Expired
US5976338A DNA analyzer Physics 31 Expired
US5644393A Extraneous substance inspection method and apparatus Physics 30 Expired
US5423111A Magnetic disk tester Emerging Cross-Sectional Technologies 29 Expired
US5898491A Surface defect test method and surface defect tester Electricity 29 Expired
US5851102A Device and method for positioning a notched wafer Emerging Cross-Sectional Technologies 26 Expired
US4685802A Small particle detection system Physics 24 Expired
US5488857A Protrusion sensor for sensing protrusion on a disc Physics 24 Expired
US5879576A Method and apparatus for processing substrates Electricity 23 Expired

Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.