KR20060020498A - Embedable antenna of fem - Google Patents

Abstract

The present invention includes the steps of: forming a ground wall on a second front end module stacked by removing foot pads in a front end module manufacturing process; Forming a ground wall in a state in which a space slightly larger than a size of an antenna to be embedded is excluded; Mounting the antenna in the center of the portion where the ground wall is not formed; A front end module capable of embedding an antenna, characterized in that a via is formed in a bottom portion of an antenna to be connected to a signal terminal, and a conventional antenna, a ceramic antenna, a planar antenna, etc. The difference overcomes the difficulty of integrating into a module such as a front end module (FEM).

Front end module (FEM), built-in antenna, ground wall

Description

Front end module with built-in antenna {Embedable antenna of FEM}             

1 is a cross-sectional view of a conventional front end module.

2 is a view showing a front end module manufacturing method according to an embodiment of the present invention.

3 is a diagram illustrating a method for embedding an antenna according to an exemplary embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

200 wafer 216 third dielectric layer

202: first front end module 218: fourth dielectric layer

204: second front end module 220: casting

206ab: 1st and 2nd chip 222: trace

208: ceramic layer 226: wire

210: foot pad 228: ball bonder

212: first dielectric layer 300: ground wall

214: second dielectric layer 302: antenna

The present invention relates to a front end module capable of embedding an antenna.

As wireless mobile technology advances, many products using handsets, wireless PDAs, and LANs are emerging, and antennas are the key communication components that determine the performance of these wireless communication products.

Antennas applied to existing wireless communication terminals mainly use external dipoles and helical antennas, but if the external antennas are not fixed, their characteristics may be modified by the user, and they are limited in various designs of wireless communication terminals. There are a number of disadvantages, including a bad look.

In order to make up for the shortcomings of such an external antenna, the selection of an internal antenna is essential.

The built-in antenna for LAN has a small interference constraint in space, so the grounding effect of adjacent circuits and cases is small, so various built-in antennas are applied to laptops, smart displays, and Internet refrigerators, but handset and wireless PDAs are limited in space. Because of this severe application of the built-in antenna is very difficult situation.

Hereinafter, an antenna mounting method of a conventional front end module will be described with reference to the accompanying drawings.

1 is a view showing a conventional front end module.                         

Referring to FIG. 1, the front end module includes a chip 100 serving as a filter, a ceramic layer part 102, a wire 120 connecting the chip 100 and the ceramic layer part 102, and a lead 122. .

The ceramic layer 102 has a ground terminal, a signal terminal, and a lower ground pattern formed on the lower side, that is, the foot pad 104.

The first dielectric 106 forming and stacking a signal pattern on the upper side, the second dielectric 108 forming and stacking an upper ground pattern on the first dielectric 106 on which the signal pattern is formed, and the second layer. Stacked on the dielectric 108.

In addition, a third dielectric 110 including a bonding pad connected to the chip 100 and a wire 120, and a fourth dielectric 112 stacked on the third dielectric 110 and having a ground pattern formed thereon. It is formed on the outside of the dielectrics.

In addition, the front end module includes a cast 114 formed between the ground pattern of the fourth dielectric 112 and the ground and signal terminals of the foot pad 104.

Here, an antenna pad is present in the foot pad 104. Therefore, the antenna is mounted by connecting the antenna input terminal to the antenna pad.

Here, the signal pattern is implemented as a stripline, and the phase shifter includes the upper and lower ground patterns and the signal pattern, that is, the trace 116.

The upper and lower ground patterns are wider to cover the trace 116 range, thereby preventing signal loss.                         

The castration 114 is formed between the top layer ground pattern of the ceramic layer portion 102 and the terminals of the lower foot pad 104 to electrically connect the electrode pattern and the plurality of terminals (ground / signal) in the ground pattern as necessary. It acts as a link.

The lead 122 serves to protect the chip in the cavity of the ceramic layer 102 from the external environment, and to remove and remove the parasitic bonds between the wires to the ground.

Accordingly, the lead 122 is electrically connected to the top ground pattern of the ceramic layer portion 102, and the connection between the top ground pattern and the ground pattern of the foot pad 104 establishes the castration 114. Is done through.

That is, the casting 114 is used as a means for connecting the ground electrode of the top layer of the ceramic layer portion 102 and the ground electrode of the foot pad 104.

However, the conventional built-in antenna as described above has a disadvantage in that it is difficult to integrate in a module such as a FEM due to the difference in method.

In addition, in the case of ceramic antennas, due to deterioration of characteristics, it is difficult to implement performance in multiple layers and externally, which is difficult to embed in modules such as FEM.

In addition, the planar antenna is difficult to apply to the FEM due to the structural problem of the planar type.

Accordingly, it is an object of the present invention to provide a front end module capable of embedding an antenna that can embed an antenna in the front end module so that a handset and a wireless PDA can perform smooth communication.

In order to achieve the above object, according to a preferred aspect of the present invention, a wafer consisting of a first front end module and a second front end module is diced to view the second front end module on the first front end module. In front end modules stacked with

Forming a ground wall while leaving a predetermined space in the foot pad portions of the stacked second front end modules;

It provides a front end module capable of embedding the antenna, comprising the step of mounting the antenna in the center of the portion where the ground wall is not formed.

The via is connected to the signal terminal by drilling a via at the bottom of the mounted antenna.

The space surrounding the built-in antenna is an empty space.

A ground wall surrounds the empty space surrounding the built-in antenna.

The outermost line of the ground wall is a ground line.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2A to 2F are diagrams illustrating a method of manufacturing a front end module according to an exemplary embodiment of the present invention.

2A illustrates a top view of a wafer 200 previously fabricated in accordance with an embodiment of the invention.

The wafer 200 is composed of a first front end module 202 and a second front end module 204.

A plate shape in which chips and wires are not mounted on the first front end module 202 and the second front end module 204 is referred to as an LTCC substrate.

The LTCC substrate may be manufactured by determining the size of the module or the number of chips to be mounted in the module according to the manufacturer's intention.

FIG. 2B shows the side view of FIG. 2A.

Referring to FIG. 2B, the LTCC substrate is composed of a ceramic layer portion 208, and the first chip 206a and the second chip 206b are mounted in two cavity regions of the ceramic layer portion 208 to wire 226. To form an LTCC module.

The ceramic layer 208 has a ground terminal, a signal terminal, and a lower ground pattern formed on the lower side, that is, the foot pad 210.

In addition, a first dielectric 212 for forming and stacking a signal pattern on the upper side, a second dielectric 214 for forming and stacking an upper ground pattern on the first dielectric 212 on which the signal pattern is formed, and the second A third dielectric 216 and a third dielectric 216 including a bonding pad stacked on the dielectric 214 and connecting the first chip 206a and the second chip 206b through a wire 226. And a fourth dielectric 218 stacked on and having a ground pattern formed thereon.

In addition, the front end module includes a cast 220 formed outside the dielectrics and between the ground pattern of the fourth dielectric 218 and the ground and signal terminals of the foot pad 210.

Here, the signal pattern is implemented as a stripline, and the phase shifter includes the upper and lower ground patterns and the signal pattern, that is, the trace 222.

The upper and lower ground patterns are wider to cover the trace 222 range, thereby preventing signal loss.

The casting 220 is formed between the top ground pattern of the ceramic layer 208 and the terminals of the lower foot pad 210 to electrically connect the electrode pattern and the plurality of terminals (ground / signal) in the ground pattern as necessary. It acts as a link.

In addition, the castillation 220 is used as a means for connecting the ground electrode of the top layer of the ceramic layer portion 208 and the ground electrode of the foot pad 210.

Here, the first front end module 202 and the second front end module 204 are different in the manufacturing process, the second front end module 204 has a foot to facilitate the attachment of the antenna, signal line connection, etc. The pad 210 is not formed.

2C illustrates a process of dicing the front end module in units of chips after completing the above process. In the dicing process, the front end module is divided into a first front end module 202 and a second front end module 204.

In this case, as described with reference to FIG. 2A, since the LTCC substrate is a wafer 200 that is prefabricated with the first front end module 202 and the second front end module 204, the ceramic layer part 208 may be formed due to dicing. ) Is not damaged.

Then, as shown in FIG. 2D, the ball bonder 228 is attached to the upper portion of the first front end module 202.

The ball bonder usually uses silver (Au) or copper (Cu).

Then, as shown in FIG. 2E, the module is placed on top of the first front end module 202 to which the ball bonder 228 is attached to face each other, and then the cut second front end module 204 is attached. make someone do.

The process of FIG. 2E requires a lead that functions to protect the first chip 206a and the second chip 206b in the cavity of the ceramic layer portion 208 from the external environment in a normal front end module process. There will be no.

Therefore, no molding or shielding process to be performed on the top layer of the module is required, and thus the efficiency of the process can be increased in time and economy.

Then, as shown in FIG. 2F, the first front end module 202 to which the ball bonder is attached and the second front end module 204 positioned to face each other with the top of the second front end module 204 are pressed to be completely pressed. Once attached, the front end module manufacturing process is complete.

Therefore, the completed front end module can reduce the size of the conventional module in half and contribute to the miniaturization of the mobile communication system.

3A and 3B illustrate a method of embedding an antenna in a completed front end module according to an exemplary embodiment of the present invention of FIG.

3A illustrates a process for creating a ground wall 300 on the bottom surface of a second front end module 204 made of a sieve with the foot pad 210 removed in a completed front end module in accordance with an embodiment of the present invention. Drawing.

Referring to FIG. 3A, the ground wall 300 is formed to a thickness sufficient to allow an antenna to be built in the bottom surface of the second front end module 204 made of the sieve from which the foot pad has been removed.

When the ground wall 300 is formed, it is formed in a state in which the space is somewhat larger than the size of the antenna to be embedded while maintaining the shape in consideration of the shape of the antenna to be built in advance.

Figure 3b is a view showing a front end module capable of embedding a completed antenna according to an embodiment of the present invention.

After the process of FIG. 3a, if the antenna is correctly positioned in the center of the empty space in which the ground wall 300 is not formed, the front end module capable of embedding the antenna according to the present invention is completed.

At this time, it is obvious to form a via at the bottom of the antenna and connect it to the signal terminal using an inductor, a capacitor, or the like.

3C is a top view when the antenna 302 is mounted on the formed ground wall 300.

Referring to FIG. 3C, the antenna 302 is accurately positioned at the center of the portion where the ground wall 300 is not formed, and the antenna circumference is left as an empty space 304.

When the antenna 302 is positioned as described above, an empty space 304 is formed at the periphery of the antenna 302, and the empty space 304 is again surrounded by the ground wall 300.

The line 308 where the ground wall 304 ends is a ground line.

Although the present invention has been described with reference to the embodiments illustrated in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible.

Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

As described above, the built-in antenna according to the present invention overcomes the disadvantage of being difficult to integrate into a module such as a front end module (FEM) due to a difference in the method of the existing built-in antenna, ceramic antenna, planar antenna, or the like. can do

Claims (5)

In a front end module in which a wafer consisting of a first front end module and a second front end module is diced to stack the second front end module in a ball bonder on the first front end module, Forming a ground wall while leaving a predetermined space in the foot pad portions of the stacked second front end modules; And mounting an antenna in the center of a portion where the ground wall is not formed. The front end module of claim 1, wherein a via is connected to a signal terminal through a via at a bottom of the mounted antenna. The front end module of claim 1, wherein the space surrounding the embedded antenna is an empty space. The front end module according to claim 2, wherein a ground wall surrounds an empty space surrounding the embedded antenna. The front end module according to claim 3, wherein the outermost line of the ground wall is a ground line.

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