The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
a and 1b are cross-sectional views illustrating a conventional shielding structure;
a is a perspective view illustrating a high frequency module with a metal wall structure according to an embodiment of the invention and
a is an exploded perspective view illustrating a high frequency module according to another embodiment of the invention and
a to 4d are views sequentially illustrating a method for manufacturing a high frequency module according to the invention.
Exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings.
a is a perspective view illustrating a high frequency module using a metal wall according to an embodiment of the invention.
Referring to
A ground (not illustrated) is formed inside or on a surface of the substrate.
The devices 22 mounted on the substrate 21 are connected to one another by a circuit (not illustrated) on the substrate 21, performing various functions.
Also, the resin molding 24 hermetically seals a high frequency device or electronic product, thereby improving moisture-resistant or impact-resistant characteristics over a conventional metal cap. Moreover, the metal cap necessitates a soldering process but an insulating resin precludes a need for such a soldering process. A material for the molding 24 is not particularly limited unless departing from a scope of the invention. The molding 24 can be made of a thermosetting resin such as an epoxy resin.
A method for forming the molding 24 is not particularly limited either, and includes examples of transfer molding, printing and injection molding. Since the metal wall has an indentation formed therein according to the invention, preferably, the molding is formed by injecting a liquid molding material.
A metal film 25 formed on the molding 24 can be formed by various methods such as deposition, sputtering and plating. The metal film 25 is made of one selected from a group consisting of gold, silver, copper and nickel. The metal film may be of a single layer, but a multi-layer without being limited thereto. In
The metal wall 26 has both ends extending to edges of the substrate 21. Furthermore, the metal wall 26 is disposed to transverse the substrate, thereby spatially separating some (or one) of the surface mounted devices 22 from the others. This blocks cross-interference from electromagnetic waves radiated from the semiconductor devices 22.
The metal wall 26 features a lightning rod structure having a planar main board in a lower part thereof and a plurality of fingers in an upper part thereof, which define a plurality of indentations. These indentations work beneficially when the liquid molding material is injected, after the metal wall 26 is disposed, to mold the semiconductor devices. That is, the molding material can flow through the indentations, thereby assuring the molding material to be evenly distributed on the substrate 21 regardless of from where the molding material is injected.
Preferably, the metal wall 26 is disposed on the substrate 21 to spatially separate some of the surface mounted devices from the others, thereby serving as a separation screen. The indentations may be formed in an upper part of the metal wall 26 at a height greater than a mounting height of the surface mounted devices. This maximizes effects of shielding electromagnetic waves resulting from the metal wall 26, also enabling the molding material to flow.
b is a front elevation view illustrating the metal wall 26 in the high frequency module of
Referring to
The lower part 26b of the metal wall 26 is connected to the ground of the substrate 21. The upper part 26a of the metal wall 26 has a top surface in contact with the metal film 25 so that the metal film 25 is electrically connected to the ground.
The metal wall 26 itself can be improved in effects of shielding electromagnetic wave from the mounting devices. Here, preferably, the metal wall 26 has a width L in excess of that of the surface mounted devices 22 and the lower part 26b of metal wall has a height h2 in excess of that H of the surface mounted devices.
Moreover, the indentations in the upper part 26a of the metal wall may be variously configured.
a is an exploded perspective view illustrating a high frequency module according to another embodiment of the invention and
Referring to
Also, according to this embodiment, a resin molding is necessarily formed to seal mounting devices 32 on a substrate 31, but not depicted in
The metal wall 36 with such a bending further ensures some of the surface mounted devices 32 to be isolated from the others, thereby elevating effects of shielding electromagnetic wave of the mounting devices.
As described above, the metal wall disposed on the substrate can be variously configured.
a to 4d are views sequentially illustrating a method for manufacturing a high frequency module according to an embodiment of the invention.
Referring to
Referring to
The metal wall 46 may be disposed on the substrate 41 to spatially separate some of the surface mounted devices from the others. This allows the metal wall 46 to block interference from electromagnetic waves radiated from the surface mounted devices.
Preferably, the metal wall 46 has both ends extending to edges of the substrate and may have a bending depending on a mounting position of the surface mounted devices 42.
Furthermore, the metal wall 46 may have indentations for serving as a pathway of a liquid material. This enables the molding resin to be evenly distributed regardless of from where the liquid molding resin is injected during molding.
Preferably, the indentations are located in an upper part of the metal wall at a height greater than a mounting height of the surface mounted devices 42. This allows the molding resin to flow without any interference and maximizes effects of shielding electromagnetic waves among the surface mounted devices.
Referring to
Here, a top surface of the metal wall 46 is exposed in a top surface of the molding 44. Preferably, the liquid molding material is injected into the mold frames 47 to be cured, and the liquid molding material cured is polished so that the top surface of the metal wall 46 is exposed in the top surface of the molding 44.
Referring to
As set forth above, according to exemplary embodiments of the invention, a high frequency module has a metal wall formed inside a molding to connect a metal film formed on the molding to a ground of a substrate, thereby further ensuring the metal film to shield electromagnetic waves.
In addition, the metal wall is disposed on the substrate to spatially separate some of surface mounted devices from the others, thereby shielding electromagnetic waves from the mounting devices. In addition, indentations are formed in the metal wall disposed inside the molding so that the metal wall can be a minimal hindrance to a molding process.
While the present invention has been shown and described in connection with the preferred embodiments, it will be apparent to those skilled in the art that modifications and variations can be made without departing from the spirit and scope of the invention as defined by the appended claims.
Number | Date | Country | Kind |
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10-2006-0036110 | Apr 2006 | KR | national |