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:
Mar. 26, 1991
Filed:
Jul. 03, 1990
Shunji Kashiwagi, Yokohama, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A high frequency and high power semiconductor device comprising unit cells of the same shape, connected in parallel and fabricated on a chip. The thermal resistance of the chip is reduced by arranging the unit cells in a zigzag pattern. The zigzag arrangement of the unit cells is such that each unit cell in a line is offset by approximately one-half pitch from the unit cells in neighboring lines. As a result of the zigzag arrangement of the unit cells, the temperature of each unit cell is less influenced by heat from the unit cells in neighboring lines than are unit cells in an orthogonal matrix. In addition, the thermal distribution of the unit cells is improved to prevent hot spots. Using the zigzag arrangement, a single transistor can output over 100 watts C.W. at more than 900 MHz.