JPH11243306A - High freqeuncy module and communication device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high frequency module which is capable of reducing a parasitic component of a concentrated constant element and miniaturizing a distributed constant element at the same time. SOLUTION: In this high frequency module 10, a ground electrode is formed on almost the entire plane of one principal plane 2a of a dielectric substrate 2 of a high dielectric constant, dielectric layers 11 of a low dielectric constant are partially formed on the other principal plane 2b, spiral inductors 4 that are concentrated constant elements, MIM capacitors 5 and a resistance are formed on the layers 11 and micro strip lines 7 that are distributed constant elements are formed in areas where the layers 11 of a low dielectric constant of the plane 2b of the substrate 2 of a high dielectric constant are not formed. According to this configuration, it is possible to improve a characteristic and miniaturize the lines 7 which are distributed constant elements due to a large wavelength compaction ratio, thereby miniaturizing the module 10, by reducing electrostatic capacity that is formed as parasitic component among the inductors 4 which are concentrated constant elements, capacitors 5, the resistance 6 and the ground electrode.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-frequency module and a communication device using the same, and more particularly to an RF of a mobile communication device.
The present invention relates to a high-frequency module used in a high-frequency band such as a step and a communication device using the same.

[0002]

2. Description of the Related Art With the recent miniaturization of mobile communication devices, especially mobile phones, there is a demand for further miniaturization of high-frequency modules used in high-frequency bands such as RF stages.

FIG. 6 shows a plan view of a high-frequency module in which a conventional passive element is formed. 6, a high-frequency module 1 has a ground electrode (not shown) formed on one main surface 2a of a dielectric substrate 2, and several ground electrodes 3, a spiral inductor 4, MIM capacitors 5 and 5a on the other main surface 2b. , A resistor 6, a microstrip line 7, and an input / output pad 8 are formed. The ground electrode 3 is formed on one main surface 2a of the dielectric substrate 2 by a through hole or the like.
Is electrically connected to a ground electrode formed at

[0004] The above MIM is a Metal Ins
It is an abbreviation of "ultra Metal" and means a structure in which two electrode layers are stacked with one insulator layer interposed therebetween. A capacitor formed with such a structure is called an MIM capacitor. Further, only the MIM capacitor 5a is a capacitor formed between the MIM capacitor 5a and the ground electrode 3.

[0005]

In the high-frequency module 1 described above, the spiral inductor 4, the MIM capacitor 5, and the resistor 6 are lumped elements, and these are connected to the ground electrode formed on one main surface 2a of the dielectric substrate 2. Is formed as a parasitic component and causes deterioration of the characteristics of the lumped element, so that it is better to be as small as possible. In particular, the higher the frequency, the stronger the tendency. In order to avoid the characteristic deterioration of the lumped element, it is effective to reduce the dielectric constant or increase the thickness of the dielectric substrate 2.

On the other hand, the microstrip line 7 is a distributed constant element, and the capacitance formed between the microstrip line 7 and the ground electrode formed on one main surface 2a of the dielectric substrate 2 is one of the factors that determine the characteristics of the element. It is one. The length of the microstrip line 7 can be shortened by increasing the wavelength shortening rate as the dielectric constant of the dielectric substrate 2 increases, so that the dielectric constant of the dielectric substrate 2 is increased to reduce the size of the high-frequency module 1. Or reducing the thickness is effective.

As described above, in the case where a lumped element and a distributed element are mixed in one high-frequency module, mutually contradictory conditions are required in terms of miniaturization, and there is a problem that realization becomes difficult. there were.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and to provide a high-frequency module and a communication device using the same, which can simultaneously reduce the parasitic component of the lumped constant element and downsize the distributed constant element. provide.

[0009]

In order to achieve the above object, a high-frequency module according to the present invention comprises a dielectric substrate having a high dielectric constant and a ground electrode formed on substantially the entire one main surface of the dielectric substrate. A low dielectric constant dielectric layer partially formed on the other main surface of the dielectric substrate; a lumped element formed on the dielectric layer; and a lumped element formed on the other main surface of the dielectric substrate. A high-frequency module comprising a distributed constant element formed in a region where the dielectric layer is not formed.

The high-frequency module according to the present invention also includes a dielectric substrate having a low dielectric constant, a ground electrode formed on substantially the entirety of one main surface of the dielectric substrate, and a partial electrode on the other main surface of the dielectric substrate. A high dielectric constant dielectric layer, a distributed constant element formed on the dielectric layer, and a dielectric layer formed on the other main surface of the dielectric substrate in a region where the dielectric layer is not formed. It is characterized by comprising lumped constant elements.

Further, the high-frequency module of the present invention has a dielectric substrate, a ground electrode formed on almost the entirety of one main surface of the dielectric substrate, and a partial electrode formed on the other main surface of the dielectric substrate. A low dielectric constant dielectric layer, a lumped element formed on the low dielectric constant dielectric layer, and a high dielectric constant dielectric partially formed on the other main surface of the dielectric substrate. Layers and
It is characterized by comprising a distributed constant element formed on the high dielectric constant dielectric layer.

According to another aspect of the present invention, there is provided a communication apparatus comprising the high-frequency module according to any one of the above aspects. , And reduction in the size of the distributed constant element can be realized at the same time. Further, in the communication device of the present invention, downsizing can be realized.

[0013]

FIG. 1 is a plan view showing one embodiment of a high-frequency module according to the present invention. FIG. 2 is a cross-sectional view of the high-frequency module shown in FIG. 1 and 2
Here, the same or equivalent parts as those in FIG. 6 are denoted by the same reference numerals, and description thereof will be omitted.

1 and 2, the dielectric substrate 2 of the high-frequency module 10 is made of a dielectric having a high dielectric constant of about 40, and a ground electrode 9 is provided on one main surface 2a of the dielectric substrate 2. Is formed. The spiral inductor 4, the MIM capacitor 5, and the resistor 6, which are lumped constant elements, have a dielectric constant of about 4 and a low dielectric constant of about 10 μm formed on the other main surface 2 b of the dielectric substrate 2. It is formed on the body layer 11.

The high-frequency module 1 constructed as described above
As a manufacturing method of 0, first, a low dielectric constant dielectric layer having a relative dielectric constant of 4 is formed on the entire other main surface 2b of the dielectric substrate 2 by spin coating or the like. Next, the dielectric layer is subjected to photo-etching or RIE (Reactive Ion).
It is partially removed by physical etching such as etching. What is left becomes the dielectric layer 11 having a low dielectric constant. Then, the spiral inductor 4, the MIM capacitor 5, the resistor 6, and the dielectric layer 11 were removed from the dielectric layer 11 by vapor deposition or plating using a metal having high conductivity such as Cu, Ag, or Au. The ground electrodes 3 and 9, the MIM capacitor 5a, the microstrip line 7, and the input / output pad 8 are formed in the portion. Since the MIM capacitor 5a is an element for forming a capacitance between the MIM capacitor 5a and the ground electrode 3, there is no need to consider a parasitic component, and the other main surface 2b of the dielectric substrate 2 does not pass through the dielectric layer 11.
Is formed directly.

As described above, by forming the spiral inductor 4, the MIM capacitor 5, and the resistor 6, which are lumped constant elements, on the dielectric layer 11 having a low dielectric constant, an effective effect between each element and the ground electrode 9 is obtained. The dielectric constant becomes smaller,
The capacitance as a parasitic component formed there is also reduced, and deterioration of the characteristics of the element can be prevented. By forming the microstrip line 7 which is a distributed constant element in a portion where the low dielectric constant dielectric layer 11 is not formed, it is possible to obtain a large wavelength reduction rate by the high dielectric constant dielectric substrate 2. The size of the high-frequency module can be reduced.

By the way, the dielectric substrate has a certain degree of irregularities on its surface unless subjected to lapping or the like. In particular, lumped-constant elements such as spiral inductors and MIM capacitors require fine processing and have very thin films. Therefore, the unevenness on the surface of the dielectric substrate causes a decrease in yield due to disconnection or short circuit. Even in such a case, since the lumped element is formed on the low dielectric constant dielectric layer, the low dielectric constant dielectric layer has an effect of flattening the irregularities on the surface of the dielectric substrate. The effect of improving the yield of the high-frequency module can also be obtained.

FIG. 3 shows another embodiment of the high-frequency module according to the present invention. 3, the same or equivalent parts as those in FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted.

In FIG. 3, the dielectric substrate 2 of the high-frequency module 20 is made of a dielectric material having a low dielectric constant of about 10 and a ground electrode (not shown) is provided on one main surface 2a of the dielectric substrate 2. Are formed. The microstrip line 7 as a distributed constant element is formed on the dielectric layer 21 having a relative dielectric constant of about 40 and a high dielectric constant of about 10 μm and formed on the other main surface 2 b of the dielectric substrate 2. Have been. The manufacturing method of the high-frequency module 20 is basically the same as that of the high-frequency module 10 except that the region for forming the dielectric layer having a high dielectric constant is different.

As described above, by forming the microstrip line 7 as a distributed constant element on the dielectric layer 21 having a high dielectric constant, the microstrip line 7 and the one main surface 2a of the dielectric substrate 2 are formed. Since the effective permittivity between the ground electrode and the ground electrode increases, the wavelength reduction ratio also increases, and the microstrip line can be reduced in size. The spiral inductors 4 and MI, which are lumped constant elements, are formed in portions where the high dielectric constant dielectric layer is not formed.
By forming the M capacitor 5 and the resistor 6, the capacitance, which is a parasitic component, can be reduced, and the characteristic deterioration of the element can be prevented.

Since the microstrip line 7 can be formed relatively thick, the high-frequency module 10
Unlike this, there is no particular effect of planarization by the dielectric layer.

FIG. 4 shows another embodiment of the high-frequency module of the present invention. In FIG. 4, the same or equivalent parts as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 4, the dielectric substrate 2 of the high-frequency module 30 is made of a dielectric material having a relative dielectric constant of about 20, and a ground electrode (not shown) is provided on one main surface 2a of the dielectric substrate 2. Are formed. The spiral inductor 4, the MIM capacitor 5, and the resistor 6, which are lumped constant elements, have a dielectric constant of about 4 and a low dielectric constant of about 10 μm formed on the other main surface 2 b of the dielectric substrate 2. It is formed on the body layer 31. The microstrip line 7, which is a distributed constant element, has a relative dielectric constant of about 40 and a thickness of 1 on the other main surface 2b of the dielectric substrate 2.
It is formed on a dielectric layer 32 having a high dielectric constant of about 0 μm. Here, the low dielectric constant dielectric layer 31 and the high dielectric constant dielectric layer 32 are separated from each other. The manufacturing method of the high-frequency module 30 is basically the same as that of the high-frequency module 20 except that the dielectric layer is formed twice.

As described above, by forming the spiral inductor 4, the MIM capacitor 5, and the resistor 6, which are lumped constant elements, on the dielectric layer 31 having a low dielectric constant, each element and one main surface of the dielectric substrate 2 are formed. Since the effective dielectric constant with the ground electrode formed in 2a is reduced, the capacitance as a parasitic component formed there is also reduced, and deterioration of the characteristics of the element can be prevented. Further, by forming the microstrip line 7 which is a distributed constant element on the dielectric layer 32 having a high dielectric constant, the microstrip line 7 and the ground electrode formed on one main surface 2a of the dielectric substrate 2 are connected. Since the effective dielectric constant between them increases, the wavelength reduction ratio also increases, and the microstrip line 7 can be reduced in size.

Further, by flattening the irregularities on the surface of the dielectric substrate 2 by the low dielectric constant dielectric layer 31, the yield of the high frequency module can be improved for the same reason as the high frequency module 10.

FIG. 5 shows a block diagram of an embodiment of a communication device constituted by using the high-frequency module 10 of the present invention. In FIG. 5, the communication device 40 is a high-frequency module 1
0, an IC 41, an antenna 42, and a signal processing circuit 43. The antenna 42 is connected to the high-frequency module 10, and the high-frequency module 10 is connected to the IC 41 by a number of connection lines, for example, wire bonding. The output of the high-frequency module 10 is connected to the signal processing circuit 43.

The IC 41 is an integrated circuit of active elements such as an amplifier, a mixer, and an oscillation circuit. The IC 41 is connected to the high-frequency module 10 so that the lumped-constant element and the distributed-constant In combination with passive elements such as, it functions as an amplifier, a mixer, an oscillation circuit, and the like.

With such a configuration, in the communication device 40, it is possible to reduce the size of the amplifier, the mixer, and the oscillator composed of the high-frequency module 10 and the IC 41, thereby reducing the size of the communication device 40 itself. Can be achieved.

In the communication device 40, the communication device is configured using one high-frequency module and one IC. However, the number of high-frequency modules and ICs is not limited to one. And ICs, and other electronic components. The communication device 40 is configured using the high-frequency module 10 illustrated in FIG. 1. However, the communication device 40 has the same operation and effect even when configured using the high-frequency modules 20 and 30 illustrated in FIGS. 3 and 4. It is.

[0030]

According to the high frequency module of the present invention, a ground electrode is formed on one main surface of a dielectric substrate having a high dielectric constant, and a dielectric layer having a low dielectric constant is formed on the other main surface. By forming a lumped constant element on the top and forming a distributed constant element in a portion where a low dielectric constant dielectric layer is not formed, a static component as a parasitic component formed between the lumped constant element and the ground electrode is formed. The characteristics can be improved by reducing the capacitance, and the size of the distributed constant element can be reduced due to a large wavelength shortening rate, and the size of the high-frequency module can be reduced accordingly.

A ground electrode is formed on one main surface of a low dielectric constant dielectric substrate, a high dielectric constant dielectric layer is formed on the other main surface, and a distributed constant element is formed thereon. The same effect can be obtained by forming a lumped element in a portion where a low dielectric constant dielectric layer is not formed.

Further, a ground electrode is formed on one main surface of a dielectric substrate having an intermediate dielectric constant, a dielectric layer having a low dielectric constant is formed on the other main surface, and a lumped element is formed thereon. The same effect can be obtained by forming a high-permittivity dielectric layer on a portion where a low-permittivity dielectric layer is not formed and then forming a distributed constant element thereon.

Further, according to the communication device of the present invention, downsizing can be realized.

[Brief description of the drawings]

FIG. 1 is a plan view showing one embodiment of a high-frequency module according to the present invention.

FIG. 2 is a sectional view of the high-frequency module of FIG. 1 taken along the line AA.

FIG. 3 is a plan view showing another embodiment of the high-frequency module of the present invention.

FIG. 4 is a plan view showing still another embodiment of the high-frequency module of the present invention.

FIG. 5 is a block diagram showing one embodiment of the communication device of the present invention.

FIG. 6 is a plan view showing a conventional high-frequency module.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 2 ... High dielectric constant dielectric substrate 2a ... One principal surface 2b ... Other principal surface 3 ... Ground electrode 4 ... Spiral inductor 5 ... MIM capacitor 6 ... Resistance 7 ... Microstrip line 8 ... Input / output pad 10 ... High frequency module 11 ... Low dielectric constant dielectric layer

Claims (4)

[Claims] 1. A dielectric substrate having a high dielectric constant, a ground electrode formed on substantially the entirety of one main surface of the dielectric substrate, and a low dielectric material formed partially on the other main surface of the dielectric substrate. And a lumped constant element formed on the dielectric layer, and a distributed constant element formed in a region of the other main surface of the dielectric substrate where the dielectric layer is not formed. High-frequency module featuring. 2. A dielectric substrate having a low dielectric constant, a ground electrode formed on substantially the entirety of one main surface of the dielectric substrate, and a high dielectric material formed partially on the other main surface of the dielectric substrate. A dielectric constant layer, a distributed constant element formed on the dielectric layer, and a lumped constant element formed in a region of the other main surface of the dielectric substrate where the dielectric layer is not formed. High-frequency module featuring. 3. A dielectric substrate, a ground electrode formed on substantially the entirety of one main surface of the dielectric substrate, and a dielectric having a low dielectric constant partially formed on the other main surface of the dielectric substrate. Layers and
A lumped element formed on the low dielectric constant dielectric layer, a high dielectric constant dielectric layer partially formed on the other main surface of the dielectric substrate, and a high dielectric constant dielectric A high-frequency module comprising a distributed constant element formed on a layer. 4. A communication device comprising the high-frequency module according to claim 1.