Mounting device for high frequency microwave devices

• US 7,729,129 B2
• Filed: 10/17/2007
• Issued: 06/01/2010
• Est. Priority Date: 11/12/2002
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Nakazawa, Isao, Shigaki, Masafumi, Yamanaka, Kazunori
• Primary Examiner(s): Levi; Dameon E
• Application Number:
  US11/873,445
• Publication Number:
  US 20080144287A1
• Time in Patent Office: 958 Days
• Field of Search: 361/760, 361/814, 361/808, 174/520, 333/247, 438/15, 438/121
• US Class Current: 361/814
• CPC Class Codes: H01L 2223/6627 Waveguides, e.g. microstrip line, strip line, coplanar line
• CPC Class Codes: H01L 23/66 High-frequency adaptations
• CPC Class Codes: H01L 25/165 Containers
• CPC Class Codes: H01L 2924/1423 Monolithic Microwave Integrated Circuit [MMIC]
• CPC Class Codes: H01L 2924/15153 the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H01L 2924/15165 Monolayer substrate
• CPC Class Codes: H01L 2924/1616 Cavity shape
• CPC Class Codes: H01L 2924/16195 Flat cap [not enclosing an internal cavity]
• CPC Class Codes: H01L 2924/16315 Shape
• CPC Class Codes: H01L 2924/166 Material
• CPC Class Codes: H01L 2924/19032 being a microstrip line type
• CPC Class Codes: H05K 1/0203 Cooling of mounted components H05K1/0272 takes precedence
• CPC Class Codes: H05K 1/021 Components thermally connected to metal substrates or heat-sinks by insert mounting
• CPC Class Codes: H05K 1/0243 Printed circuits associated with mounted high frequency components
• CPC Class Codes: H05K 1/142 Arrangements of planar printed circuit boards in the same plane, e.g. auxiliary printed circuit insert mounted in a main printed circuit
• CPC Class Codes: H05K 1/182 associated with components mounted in the printed circuit board, e.g. insert mounted components [IMC]
• CPC Class Codes: H05K 2201/0323 Carbon
• CPC Class Codes: H05K 2201/09745 Recess in conductor, e.g. in pad or in metallic substrate
• CPC Class Codes: H05K 2201/10166 Transistor
• CPC Class Codes: H05K 2201/10409 Screws
• CPC Class Codes: H05K 3/0061 : onto a metallic substrate, e.g. a heat sink heat sinks for electric apparatus H05K7/20

Abstract

In a package mounting structure for mounting a package on a case, wherein the package internally incorporates at least one of a high-frequency transistor, MIC and MMIC used in the microwave to millimeter-wave band, and a base thereof is formed of metal and serves as ground, an electrically conductive sheet having excellent thermal conductivity and exhibiting restorability and having a size identical with that of the base of the package is laid on the case at a package-bearing location, the package and sheet are fastened together by two or more screws, and the sheet is mounted on the case while it is pressed by a pressing force of 10 N/cm² or greater owing to fastening.

Claims

1. An electronic device having a package internally incorporating at least one of a high-frequency transistor, a microwave integrated circuit (MIC), and a monolithic microwave integrated circuit (MMIC) used in a microwave to millimeter-wave band, a base thereof being formed of metal and serving as ground, and a case on which the package is mounted, comprising:

two circuit boards that are mounted at circuit-board-bearing locations on the case so that the two circuit boards sandwich, a package-bearing location on the case;

a package reception portion, formed at the package-bearing location, which receives the package and has a step on each of four sides, at least one step that is among the four steps and through which microwaves to millimeter-waves do not pass being inclined; and

a graphite sheet that is laid on an entirety of the package reception portion and circuit-board-bearing locations, wherein the package and the graphite sheet are fastened together in the package reception portion and attached to the case by two or more screws.