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:
Sep. 11, 1990
Filed:
Sep. 30, 1988
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A microwave monolithic integrated circuit comprising a GaAs substrate having upper and lower opposed surfaces, an active region and at least one passive region produced on the upper surface of the substrate, and a heat sink produced on the lower surface of the substrate, wherein the substrate thickness beneath the active region is smaller than the substrate thickness beneath at least one passive region, thereby disposing the heat sink near the active region to improve heat dissipation therefrom. The active region and the passive regions are separated by intermediate areas and the substrate thickness beneath the intermediate areas is smaller than the substrate thickness beneath the active region such that the heat sink at least partially surrounds the substrate beneath the active region. Each passive region is associated with a respective microwave transmission line having a predetermined width and a desired characteristic impedance and the thickness of the substrate beneath each of the passive regions is established individually based on the width and the desired characteristic impedance of each respective microwave transmission line.