JP3750796B2 - Module for mobile communication equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a module used for a mobile communication device such as a mobile phone, a local area network (LAN), or the like.
[0002]
[Prior art]
Japanese Patent No. 2983016 discloses a multiband high-frequency switch module in which a diplexer connected to an antenna and a transmission / reception switching high-frequency switch are configured in one chip to be miniaturized. In the chip, a diplexer is formed by a laminated structure in a laminated substrate produced by laminating and firing green sheets, and a semiconductor chip, a capacitor having a large capacity, and the like are mounted on the substrate.
[0003]
[Problems to be solved by the invention]
In the above-mentioned conventional module, many passive elements are realized by a substrate having a laminated structure, so that the substrate is likely to be warped or cracked when the ceramic is fired, and the dielectric material and the magnetic material are different. If the materials are fired at the same time, warpage and cracks are more likely to occur, resulting in a problem of poor yield.
[0004]
On the other hand, when a resin or a composite material in which a functional material powder such as dielectric powder or magnetic powder is mixed in a laminate substrate is used for the laminate substrate, the resin has high hygroscopicity, so that the characteristics may deteriorate over time. In particular, the diplexer is a portion connected to the antenna, and it is necessary to reduce the loss as much as possible, and since it is required that the deterioration over time is small, the deterioration over time due to the hygroscopic property becomes fatal.
[0005]
In view of the above-mentioned problems of the prior art, the present invention achieves a high yield and a high reliability when realizing a module for a mobile communication device including at least a front-end module of a multiband system, and can be downsized. It aims at providing what can be planned.
[0006]
[Means for Solving the Problems]
The module for a mobile communication device according to claim 1 comprises a substrate configured in a multilayer structure by a resin or a composite material obtained by mixing a resin and a functional material powder, and a semiconductor component built in or mounted on the substrate. A module for a mobile communication device of a multiband system constituting a front end module,
The diplexer connected to the antenna is constituted by one ceramic chip and embedded in the substrate .
[0007]
In this way, if the diplexer connected to the antenna is formed of a ceramic chip, the ceramic chip has low hygroscopicity, and therefore, there is little secular change and the characteristics are stable. In addition, since the substrate is realized with a laminated structure of resin or resin and functional material powder, warpage and cracks are less likely to occur in a laminated structure with many built-in elements and different materials compared to a ceramic laminated sintered body, and the yield is high. improves. In addition, since at least the multiband type front-end module including the diplexer is configured as one chip, the diplexer that is the chip is embedded in the substrate, so that the size can be reduced.
[0008]
The mobile communication device module according to claim 2 is the module according to claim 1,
The module for mobile communication device includes a low dielectric constant layer having a relative dielectric constant of 2.5 to 5.0 and a high dielectric constant layer having a relative dielectric constant higher than that layer, and the diplexer is used as the low dielectric constant layer. It is characterized by being buried .
The mobile communication device module according to claim 3 is the module according to claim 2,
The relative dielectric constant of the high dielectric constant layer is 15.0 to 30.0.
It is characterized by that.
[0009]
Since the diplexer is embedded in the low dielectric constant layer in this way, mutual interference between the diplexer and other elements due to capacitive coupling can be prevented.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is an example of a block circuit for realizing a module for a mobile communication device according to the present invention. This embodiment is used for both the GSM system (900 MHz band) and the DCS system (1.8 GHz band), and shows an example of configuring a front-end module. In FIG. 1, 1 is a front end module, 2 is an antenna, T1 and T5 are GSM transmission circuits and terminal electrodes connected to the reception circuit, and T11 and T7 are connected to DCS transmission and reception circuits, respectively. Terminal electrode. Arrows indicate the signal flow of each method.
[0011]
3 and 4 are low pass filters for removing harmonics contained in DCS and GSM transmission signals, 5 is a DCS transmission / reception switching switch, 6 is a GSM transmission / reception switching switch, and 7 is a DCS transmission switch. It is a diplexer provided as a branching circuit that separates a signal and a GSM signal.
[0012]
FIG. 2 is a circuit diagram illustrating a circuit configuration of the front end module 1. In FIG. 2, T1 to T11 are terminal electrodes provided on the outside of a laminate 8 (see FIG. 3A) described later. The terminal electrode T9 is a terminal electrode to the antenna, and the coils L1, L2, and L11 and the capacitors C1, C11, and C12 constitute the diplexer 7 that is a branching circuit. A circuit (a circuit on the right side in the drawing) from the coil L1 and the capacitor C1 to the terminal electrode T11 is a circuit corresponding to the DCS system. A circuit from the coil L11 and the capacitor C11 to the terminal electrode T1 (the circuit on the left side in the drawing) corresponds to the GSM system.
[0013]
In the circuit corresponding to the DCS system on the right side, T11 is a terminal electrode connected to the DCS system transmission circuit. T7 is a terminal electrode connected to a DCS receiving circuit. T8 and T10 are terminal electrodes to which a control signal for performing DCS transmission / reception switching is applied. The coil L6 and the capacitors C6 to C8 constitute the low-pass filter 3. The diodes D1 and D2, the coils L3 to L5, and the capacitors C2 to C5 and C9 constitute a transmission / reception changeover switch 5.
[0014]
In the left circuit corresponding to the GSM system, T1 is a terminal electrode connected to the GSM transmission circuit. T5 is a terminal electrode connected to a GSM receiving circuit. T2 and T4 are terminal electrodes to which control signals for GSM transmission / reception switching are applied. The coil L14 and the capacitors C17 to C19 constitute the low-pass filter 4. The diodes D11 and D12, the coils L12 and L13, and the capacitors C13 to C16 constitute a transmission / reception changeover switch 6.
[0015]
FIG. 3A is a perspective view showing the overall configuration of the module of the present embodiment, and illustration of terminal electrodes provided on the side surfaces is omitted. FIG. 3B is a layer structure diagram of the module. 4A is a sectional view of the module, FIG. 4B is a perspective view showing a diplexer embedded in the module, and FIG. 4C is a layer structure diagram thereof.
[0016]
The front end module includes a laminated body (base substrate) 8 and semiconductor components 19 such as the diodes D 1 and D 2 mounted on the laminated body 8. As a mounted component, a passive element 19A such as a high-capacitance capacitor, an inductor, or a resistor may be provided. These mounted components may be built in the laminate 8.
[0017]
As shown in FIG. 3 (B) and FIG. 4 (A), the laminated body 8 includes a low dielectric constant layer 9a to 9g in which a dielectric powder is mixed with a resin or resin in which a glass cloth is embedded as necessary. In accordance with the above, a resin in which a glass cloth is embedded or a high dielectric constant layer 10a, 10b in which a dielectric powder is mixed in a resin is formed by laminating the inductor conductors 11, 14 and the capacitor electrodes 12, 15 between the layers. It becomes. Reference numeral 16 denotes a ground electrode formed on the bottom surface of the laminated body 8, and 17 denotes a land to which the semiconductor component 19 is fixed.
[0018]
Reference numeral 20 denotes a cavity provided in the laminate 8, and a diplexer 7 made of a ceramic chip is embedded in the cavity 20. As shown in FIGS. 4B and 4C, the diplexer 7 includes layers 21a to 21f made of ceramic green sheets, and a ground electrode 18, an inductor conductor 22, a capacitor electrode 23, and via holes are formed on these green sheets. The conductor 24 is formed by printing using Ag, Cu, Ag—Pd or the like, and these are stacked, provisionally stacked, integrated by hot pressing, cutting, firing, terminal electrode formation, and a diplexer as a chip 7 is produced. The ceramic chip may be manufactured by a printing method in which a dielectric sheet or a magnetic paste and a conductor are alternately printed to form a layer instead of using a green sheet.
[0019]
FIG. 5 is a diagram showing a process of incorporating the chip-shaped diplexer 7 in the substrate 1. As shown in FIG. 5A, an adhesive sheet 26 is pasted on the copper foil 25, a land 27 for connecting a terminal on the bottom surface of the chip 7 is drilled with a laser, and solder paste is applied to the hole. Form. Next, as shown in FIGS. 5B and 5C, the chip 7 is mounted on the land 27.
[0020]
Further, as shown in FIG. 5C, the three layers serving as the low dielectric constant layers 9b to 9d in which the cavity 20 having the same size as or slightly larger than the chip 7 is formed at the position of the chip 7 are integrated. A core substrate is prepared. As shown in FIG. 5D, the cavity 20 is fitted into the chip 7 and the core substrate is overlaid on the adhesive sheet 26. Here, the thickness of the three-layer core substrate forming the low dielectric constant layers 9b to 9d is substantially the same as or larger than that of the chip 7.
[0021]
Next, as shown in FIG. 5D, the prepreg to be the low dielectric constant layer 9a is stacked on the three-layer core substrate and hot-pressed. As will be described later, the chip 7 is formed by the fluidity of the prepreg. The gap between the upper surface and the side surface of the is filled with prepreg.
[0022]
Next, as shown in FIGS. 5E and 5F, the copper foil 30 is pasted with an adhesive sheet 29.
[0023]
Thereafter, the upper and lower copper foils 25 and 30 are patterned by etching by a general method of printed circuit board. In this case, the land 17 is formed by etching the upper copper foil 30, and a wiring pattern having a role of connecting a chip is formed by etching the lower copper foil 25.
[0024]
The low dielectric constant layers 9a to 9g preferably have a relative dielectric constant of 2.5 to 5.0. The high dielectric constant layers 10a and 10b preferably have a relative dielectric constant of 15.0 to 30.0. In this embodiment, the low dielectric constant layers 9a to 9g are vinyl benzyl resin mixed with a flame retardant and having a glass cloth embedded with a relative dielectric constant of 3.5 and a thickness of 100 μm. The high dielectric constant layers 10a to 10d were made of an epoxy resin in which a dielectric powder made of barium titanate and a flame retardant were mixed and a glass cloth was embedded, having a relative dielectric constant of 20 and a thickness of 60 μm.
[0025]
As the resin, in addition to the above, phenol resin, bismaleimide triazine resin (BT resin), polyphenylene ether resin (PPE) and the like are used. In addition to the above, the dielectric powder mixed with these resins includes, for example, CaTiO ₃ system, SrTiO ₃ system, BaTiO ₃ —BaZrO ₃ system, BaO—TiO ₂ —Nd ₂ O ₃ system, BaO-4TiO ₂ system. Ceramic dielectric powder such as, dielectric single crystal powder, metal powder having a dielectric film, etc. are used. Further, as a material for constituting the low dielectric constant layers 9a to 30g, a mixture of dielectric powder may be used. As the dielectric powder for the low dielectric constant layer, ceramic dielectric powder such as alumina, dielectric Single crystal powder, metal powder having a dielectric film, or the like is used. Of course, the dielectric powder and resin used in the present invention are not limited to these materials.
[0026]
This laminated body is obtained by attaching a copper foil to the prepreg made of the composite material, semi-curing and etching so that a conductor pattern for a plurality of laminated bodies is formed, and then newly adding a prepreg and a copper foil. The process of sticking and etching can be repeated, or a thick film printing method or a thin film forming method can be used for a build-up method or conductor formation without using a glass cloth.
[0027]
In addition, a magnetic layer in which a magnetic powder is mixed with a resin may be formed in the inductor forming portion. Examples of the magnetic powder mixed with the resin include ferrite powders such as Mn—Mg—Zn and Ni—Zn, Metal magnetic powder, magnetic single crystal powder, magnetic metal powder having an insulating film, and the like are used.
[0028]
In addition to copper, silver, nickel, tin, zinc, aluminum, or the like can be used as conductors such as lands 17, wiring patterns, inductor conductors 11 and 14, and capacitor electrodes 12 and 15.
[0029]
As described above, if the diplexer 7 connected to the antenna is formed of a ceramic chip, the ceramic chip has low hygroscopicity, and therefore, there is little secular change and the characteristics are stabilized. In addition, since the substrate is realized with a laminated structure of resin or resin and functional material powder, warpage and cracks are less likely to occur in a laminated structure with many built-in elements and different materials compared to a ceramic laminated sintered body, and the yield is high. improves. In addition, since at least the multiband front-end module including the diplexer is configured as one chip, miniaturization can be achieved. Further, by embedding the diplexer 7 in the laminated body 8, further miniaturization can be achieved. In addition, since the diplexer is embedded in the low dielectric constant layer, mutual interference between the diplexer and other elements due to capacitive coupling can be prevented.
[0030]
When carrying out the present invention, semiconductor components and passive elements other than the diplexer chip 7 may be embedded in the stacked body 8. Further, the module of the present invention may be configured to include other parts such as all or part of a transmission circuit and a reception circuit in addition to a front end module including a diplexer, a switch, and a filter of a mobile communication device. Good.
[0031]
【The invention's effect】
According to the first aspect, the diplexer connected to the antenna is formed of a ceramic chip, and the ceramic chip has low hygroscopicity, and therefore has little secular change and stable characteristics. In addition, since the substrate is realized with a laminated structure of resin or resin and functional material powder, warpage and cracks are less likely to occur in a laminated structure with many built-in elements and different materials compared to a ceramic laminated sintered body, and the yield is high. improves. In addition, since at least the multiband type front-end module including the diplexer is configured as one chip , and the diplexer is embedded in the substrate, miniaturization can be achieved.
[0032]
According to the second and third aspects, since the diplexer is embedded in the low dielectric constant layer, mutual interference between the diplexer and other elements due to capacitive coupling can be prevented .
[Brief description of the drawings]
FIG. 1 is an example of a block circuit for realizing a module for mobile communication equipment according to the present invention.
FIG. 2 is an example of an equivalent circuit that realizes the mobile communication device module of FIG. 1;
FIG. 3A is a perspective view showing the overall configuration of the module of the present embodiment, and FIG. 3B is a layer structure diagram of the module.
4A is a sectional view of the module, FIG. 4B is a perspective view showing a diplexer embedded in the module, and FIG. 4C is a layer structure diagram thereof.
FIGS. 5A to 5F are process diagrams showing a part of the manufacturing process of the present embodiment. FIGS.
[Explanation of symbols]
1: front end module, 2: antenna, 3, 4: low-pass filter, 5, 6: switch, 7: diplexer, 8: laminate, 9a-9g: low dielectric constant layer, 10a, 10b: high dielectric constant layer, DESCRIPTION OF SYMBOLS 11, 14: Inductor conductor, 12, 15: Capacitor electrode, 16: Ground electrode, 17: Land, 18: Ground electrode, 19: Semiconductor component, 19A: Passive element, 20: Cavity, 21a-21f: Layer, 22: Inductor conductor, 23: capacitor electrode, 24: via-hole conductor, 25: copper foil, 26: adhesive sheet, 27: land, 29: adhesive sheet, 30: copper foil

Claims (3)

A multiband moving body comprising at least a front end module comprising a substrate configured in a multilayer structure by a resin or a composite material in which a resin and a functional material powder are mixed, and a semiconductor component built in or mounted on the substrate A communication device module,
A module for a mobile communication device, wherein a diplexer connected to an antenna is constituted by a single ceramic chip and embedded in the substrate . The mobile communication device module according to claim 1,
The module for mobile communication device includes a low dielectric constant layer having a relative dielectric constant of 2.5 to 5.0 and a high dielectric constant layer having a relative dielectric constant higher than that layer, and the diplexer is used as the low dielectric constant layer. A module for a mobile communication device characterized by being embedded . The module for mobile communication equipment according to claim 2,
The relative dielectric constant of the high dielectric constant layer is 15.0 to 30.0.
A module for mobile communication equipment characterized by the above.

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