Inventor · Yokkaichi, JP

Kazumasa Hiramatsu

15Patents
10h-index
26Co-inventors
68Inventor score

Filing activity: Jan 26, 1988 → May 2, 2006

Most-cited inventions

PatentTitleAreaCited byStatus
US4911102A Process of vapor growth of gallium nitride and its apparatus Electricity 314 Expired
US5122845A Substrate for growing gallium nitride compound-semiconductor device and light emitting diode Electricity 137 Expired
US6225650A GAN group crystal base member having low dislocation density, use thereof and manufacturing methods thereof Electricity 131 Expired
US5770887A Gan single crystal Electricity 124 Expired
US6503610B2 Group III-V compound semiconductor and method of producing the same Emerging Cross-Sectional Technologies 82 Expired
US5218216A Gallium nitride group semiconductor and light emitting diode comprising it and the process of producing the same Electricity 66 Expired
US5846844A Method for producing group III nitride compound semiconductor substrates using ZnO release layers Emerging Cross-Sectional Technologies 58 Expired
US5370738A Compound semiconductor vapor phase epitaxial device Chemistry; Metallurgy 37 Expired
US5810925A GaN single crystal Electricity 30 Expired
US8053811B2 Group 3-5 nitride semiconductor multilayer substrate, method for manufacturing group 3-5 nitride semiconductor free-standing subtrate, and semiconductor element Electricity 14 Expired
US6756246B2 Method for fabricating III-V group compound semiconductor Electricity 9 Expired
US6734515B1 Semiconductor light receiving element Emerging Cross-Sectional Technologies 7 Expired
US7399687B2 Substrate of gallium nitride single crystal and process for producing the same Electricity 6 Expired
US6844574B1 III-V compound semiconductor Electricity 3 Expired
US6946308B2 Method of manufacturing III-V group compound semiconductor Electricity 3 Expired

Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.