Circuit module, and electronic device using the module

Abstract

Provided is a circuit module comprising a circuit substrate, a plurality of electronic parts mounted on one face of the circuit substrate, a cylindrical member so erected from that face as to enclose the electronic parts, a folded portion folded inward at a predetermined height position of the cylindrical member, and a resin portion constituted of such a sealing resin to cover the electronic parts at least partially in the cylindrical member as is filled to a level to reach the leading end of the folded portion. This constitution joins the sealing resin and the two faces of the folded portion so that it can provide the circuit module which has an increased strength and which is thin but has a high strength. Moreover, through holes are formed in such a region of the folded portion as is exposed from the sealing resin. As a result, it is possible not only to eliminate the cavity, which might otherwise be formed in the folded portion (or the C-shaped portion) by the expansion of the residual gas, but also to suppress the bulge, as might otherwise be created on the upper resin face by the cavity which is formed by the gas moved from the inside of the folded portion to the resin, or the crater-shaped undulations, as might otherwise be created in the upper face of the resin portion when the gas in the frame goes to the upper face of the resin.

Description

technical field [0001] The present invention relates to a circuit module and an electronic device using the circuit module, and more particularly, to a circuit board in which a plurality of electronic parts are mounted (attached) on a circuit formed with wiring conductors It also relates to an electronic device (with portability) using the circuit board, such as a cellular phone and a portable communication terminal. Background technique [0002] A circuit board used in a portable terminal such as a cellular phone includes a substrate on which a circuit pattern is formed and a plurality of electronic components mounted such that terminal portions thereof are fixed to the circuit pattern by solder. [0003] Furthermore, in recent years, among such circuit boards, a structure has been proposed in which the IC package is fixed to the motherboard by providing a reinforcement frame that covers the periphery of the upper surface of the IC package and can be filled with resin. wit...

AI Technical Summary

Problems solved by technology

[0004] In the above structure, the resin can be filled from all sides of the perimeter with respect to the solder balls at the lower surface of the package (to be connected to the motherboard), so the resin directly fills and seals the connection between the solder balls and the motherboard , where poor connections due to peeling become a problem in BGA type IC packages

[0005] In the above structure, there is a limit to the viscosity of the resin that can be used, unless the resin has a certain viscosity, it will cause the resin to flow out from the resin pouring hole, which becomes the cause of flash

On the other hand, when the viscosity is high, the smoothness after curing decreases, so that there is a problem of poor appearance

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