KR102585867B1 - Power amplifier circuit and communication apparatus - Google Patents

Abstract

[Project] Provide a power amplifier circuit that suppresses parasitic capacitance between the emitter and collector and suppresses heat rise even when outputting high power at high frequency.
[Solution] Provided with a lower layer metal on which an emitter or collector is wired, and an upper layer metal on which a collector or emitter is wired, the upper layer metal is thinned out in area, and the lower layer metal is placed in the area where the upper layer metal is thinned. A high-frequency amplification circuit is provided, characterized in that wiring is led out to the height of the upper metal layer.

Description

Power amplifier circuit and communication device {POWER AMPLIFIER CIRCUIT AND COMMUNICATION APPARATUS}

[0001]

The present invention relates to power amplifier circuits and communication devices.

[0002]

A semiconductor integrated circuit that integrates semiconductor devices such as diodes, transistors, and MOS-FETs (metal-oxide-semiconductor field-effect transistors), and the driving control circuits of these semiconductor devices on a single silicon substrate. ((Integrated Circuit; IC) has been developed.

[0003]

The transistor of a power amplifier connected to an antenna that performs wireless communication, such as in a mobile phone, requires high frequency and high power output. In semiconductor ICs for realizing high-frequency, high-power output, high-power output is often achieved by arranging a plurality of bipolar transistors of the same layout pattern with small dimensions. When the bipolar transistor outputs high power, a large amount of heat is generated. It is known that the heat becomes uneven among a plurality of bipolar transistors, causing operational instability such as thermal oscillation of only some transistors.

[0004]

Accordingly, a technology has been proposed to equalize the heat generated in bipolar transistors among the bipolar transistors. For example, in Non-Patent Document 1, a thick metal layer is formed on the uppermost layer of the emitter wiring of the bipolar transistor immediately above the pattern area of the bipolar transistor, thereby thermally forming a group of uniformly arranged bipolar transistors. A technology for uniformity and suppressing heat has been disclosed.

[0005] [Non-patent Document 1] Microwave Symposium Digest, 1997., IEEE MTT-S International, pp949-952 vol.2, Power performance of thermally-shunted heterojunction bipolar transistors, Jenkins, T. et.al.,

[0006]

However, even if the prior art disclosed in Non-Patent Document 1 is used, the transistor density must be increased in order to reduce the size of the semiconductor IC due to cost and packaging requirements, and with the increase in transistor density, heat increase must be suppressed. There was a problem that it was difficult to do. Additionally, in a power amplifier realized using an integrated circuit of bipolar transistors, when outputting high power, a large current flows through the emitter and collector, so the emitter and collector need to be wired with relatively thick wires. However, there was also the problem that by using thick wiring between the emitter and the collector, a large parasitic capacitance was generated between the emitter and the collector.

[0007]

Accordingly, the present invention was made in consideration of the above problems, and the purpose of the present invention is to suppress the parasitic capacitance between the emitter and the collector and to suppress heat rise even when outputting high power at high frequency. The goal is to provide new and improved power amplifier circuits and communication devices whenever possible.

[0008]

In order to solve the above problem, according to one aspect of the present invention, a lower layer metal on which an emitter or a collector is wired and an upper layer metal on which a collector or an emitter are wired are provided, and the upper metal is thinned out in area, A high-frequency amplifier circuit is provided, characterized in that the wiring of the lower layer metal is drawn from the area where the upper layer metal has been thinned.

[0009]

The wiring drawn out from the lower metal may be located on the ground back via.

[0010]

The wiring drawn out from the lower layer metal may be arranged in an area surrounded by at least three sides of the thinned upper layer metal.

[0011]

The wiring extending from the lower metal may be extended to the height of the upper metal.

[0012]

Pads may be formed on wiring extending from the lower metal layer, and the pads may be connected with wire bonds.

[0013]

Pads may be formed on the wiring extending from the lower metal layer, and the pads may be connected with metal wiring.

[0014]

In addition, in order to solve the above problem, according to another aspect of the present invention, a communication device is provided, characterized by comprising the high-frequency amplification circuit.

[0015]

As explained above, according to the present invention, a new and improved power amplifier circuit and communication device are provided that can suppress the parasitic capacitance between the emitter and the collector and suppress heat rise even when outputting high power at high frequency. can do.

[0016]
[Figure 1] is an explanatory diagram showing a high-frequency power amplifier 10 according to an embodiment of the present invention in a plan view.
[Figure 2] is an explanatory diagram showing the high-frequency power amplifier 100 according to an embodiment of the present invention in a plan view.
[FIG. 3] is an explanatory diagram schematically showing the cross section of the high-frequency power amplifier 100 shown in FIG. 2.
[Figure 4] is an explanatory diagram schematically showing the cross section of the high-frequency power amplifier 100.
[Figure 5] is an explanatory diagram schematically showing the cross section of the high-frequency power amplifier 100.
[FIG. 6] is an explanatory diagram showing an example of the configuration of a wireless communication device 1000 including a high-frequency power amplifier 100 according to an embodiment of the present invention.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, in this specification and drawings, components having substantially the same functional configuration are assigned the same reference numerals to omit redundant description.

[0018]

<1. Background>

First, before explaining the embodiment of the present invention in detail, the background of the embodiment of the present invention will be explained.

[0019]

As described above, the transistor of a power amplifier connected to an antenna that performs wireless communication in a mobile phone or the like requires high frequency and high power output. In semiconductor ICs for realizing high-frequency, high-power output, high-power output is obtained by arranging a plurality of bipolar transistors with the same layout pattern in small dimensions.

[0020]

In a power amplifier realized using an integrated circuit of bipolar transistors, a circuit in which a plurality of bipolar transistors that output high frequency and high power are arranged in the same layout pattern, when outputting high power, a large current flows through the emitter and collector. . In order to pass a large current through the emitter and collector, the emitter and collector need to be wired with relatively thick wires.

[0021]

However, by making the emitter and collector wiring thick, a large parasitic capacitance is generated between the emitter and the collector. When deriving power characteristics by optimizing the impedance of the output matching circuit, the power characteristics may be limited due to the parasitic capacitance between the emitter and collector.

[0022]

Additionally, in semiconductor ICs for realizing high-frequency, high-power output, high-power output is often obtained by arranging a plurality of bipolar transistors with the same layout pattern in small dimensions. When the bipolar transistor outputs high power, a large amount of heat is generated. It is known that the heat becomes non-uniform among a plurality of bipolar transistors, causing operational instability, such as only some transistors thermally oscillating.

[0023]

As a technology for equalizing the heat generated by bipolar transistors among the bipolar transistors, even if the prior art disclosed in Non-Patent Document 1 is used, the density of transistors must be increased to reduce the size of the semiconductor IC due to cost and packaging requirements. Therefore, there was a problem that it was difficult to suppress the heat rise.

[0024]

Accordingly, in order to realize high-frequency and high-power output, the inventor of the present invention, when arranging a plurality of bipolar transistors of the same layout pattern with small dimensions, suppresses heat increase in a specific bipolar transistor by uniformizing heat among the bipolar transistors. , a detailed study was conducted on high-frequency amplification circuit technology that can improve power characteristics such as maximum output power and power efficiency by suppressing parasitic capacitance between the emitter and collector.

[0025]

As a result, the inventor of the present invention arranged a plurality of bipolar transistors of the same layout pattern with small dimensions in order to realize high frequency and high power output by thinning the upper layer metal of the collector within a predetermined range, as described below. High-frequency amplification that can improve power characteristics such as maximum output power and power efficiency by suppressing the heat rise of specific bipolar transistors by equalizing heat between bipolar transistors and suppressing parasitic capacitance between emitter and collector. I ended up devising a circuit.

[0026]

Above, the background of the embodiment of the present invention has been described. Next, embodiments of the present invention will be described in detail.

[0027]

<2. One embodiment of the present invention>

Below, an example of a high-frequency amplifier circuit according to an embodiment of the present invention will be described. First, when multiple bipolar transistors of the same layout pattern are arranged, by simply thinning the upper layer metal of the collector into a rectangular shape, it is possible to suppress parasitic capacitance between the emitter and collector and equalize heat among the bipolar transistors. An example of a high-frequency amplifier circuit is shown.

[0028]

Figure 1 is an explanatory diagram showing a high-frequency power amplifier 10 according to an embodiment of the present invention in a plan view. Shown in FIG. 1 is a high-frequency power amplifier 10 in which a lower layer metal 11 is formed on a semiconductor substrate such as silicon, and an upper layer metal 12 is formed on top of the lower layer metal 11. The high-frequency power amplifier 10 shown in FIG. 1 uses the lower layer metal 11 as the emitter wiring of a bipolar transistor, and the upper layer metal 12 as the collector wiring.

[0029]

Also, Figure 1 shows a bipolar transistor pattern area 13 consisting of an emitter and base 14 made of lower layer metal 11 and a collector made of upper layer metal 12.

[0030]

In the high-frequency power amplifier 10 shown in FIG. 1, the upper layer metal 12 is not entirely covered on the lower layer metal 11, but the upper layer metal 12 is thinned out to a predetermined range. In the example shown in FIG. 1, the upper layer metal 12 is thinned out so that the shape is rectangular. Of course, the size of each metal shown in the drawing and the shape and area when the upper metal 12 is thinned are not limited to the example shown in FIG. 1.

[0031]

In the plurality of bipolar transistors formed in the bipolar transistor pattern area 13, a large amount of heat is generated when high power is output. This heat does not generate much at both ends (top and bottom of the drawing) of the high-frequency power amplifier 10, but generates more heat toward the center.

[0032]

When thinning the upper layer metal 12, as shown in FIG. 1, it is preferable to thin out the area so that the thinned area and the non-thinned area appear alternately in the vertical direction of the drawing. By thinning the upper metal layer 12 in this way, it becomes possible to equalize heat between bipolar transistors formed in the bipolar transistor pattern region 13. Additionally, as shown in FIG. 1, by thinning the upper metal layer 12, parasitic capacitance between the emitter and the collector can be suppressed.

[0033]

In addition, Figure 1 shows a high-frequency power amplifier 10 provided with a bipolar transistor pattern area 13 on the right side of the drawing, but on the left side of the drawing, not shown, similarly, an emitter and a base ( 14) and a collector formed by the upper metal layer 12, a bipolar transistor pattern area may be provided.

[0034]

As shown in FIG. 1, by thinning the upper layer metal 12 within a predetermined range, the high-frequency power amplifier 10 shown in FIG. 1 can suppress parasitic capacitance between the emitter and the collector. Even in the high-frequency power amplifier 10 as shown in FIG. 1 in which the upper layer metal 12 is thinned out to a predetermined range, it is important to equalize heat between bipolar transistors and suppress parasitic capacitance between the emitter and collector. It becomes possible.

[0035]

Shows examples of other high-frequency amplifier circuits. Figure 2 is an explanatory diagram showing a high frequency power amplifier 100 according to an embodiment of the present invention in a plan view. Shown in FIG. 2 is a high-frequency power amplifier 100 in which a lower layer metal 101 is formed on a semiconductor substrate such as silicon, and an upper layer metal 102 is formed on top of the lower layer metal 101. The high-frequency power amplifier 100 shown in FIG. 2 uses the lower layer metal 101 as the emitter wiring of a bipolar transistor, and the upper layer metal 102 as the collector wiring.

[0036]

Additionally, FIG. 2 shows a bipolar transistor pattern area 103 consisting of an emitter and a base 104 made of the lower layer metal 101 and a collector made of the upper layer metal 102.

[0037]

In the high-frequency power amplifier 100 shown in FIG. 2, the upper layer metal 102 is not entirely covered on the lower layer metal 101, but the upper layer metal 102 is thinned out to a predetermined range. In the example shown in FIG. 2, the upper layer metal 102 is thinned out so that the shape is rectangular. Of course, the size of each metal shown in the drawing and the shape and area when the upper metal 102 is thinned are not limited to the example shown in FIG. 2.

[0038]

Furthermore, in the high-frequency power amplifier 100 shown in FIG. 2, the emitter wiring is led out from the lower layer metal 101 to the height of the upper layer metal 102 in the area where the upper layer metal 102 has been thinned. In this way, by drawing the emitter wiring from the lower layer metal 101 to the height of the upper metal 102, the heat generated by the bipolar transistor formed in the bipolar transistor pattern region 103 is transferred to the high frequency power amplifier 10 shown in FIG. ), it becomes possible to release it to the outside more efficiently.

[0039]

Additionally, in the example shown in FIG. 2, the emitter wiring extending to the height of the upper metal 102 is surrounded on all sides by the collector wiring of the upper metal 102, but the emitter wiring is surrounded on at least three sides by the collector wiring. It may be in the same form as it is.

[0040]

In addition, the high-frequency power amplifier 100 shown in FIG. 2 leads the emitter wiring from the lower metal 101 to the height of the upper metal 102 in the area where the upper metal 102 has been thinned, but the upper metal 102 is thinned out. The emitter wiring leading out to the height of (102) is led out so as to be directly above the back via (105).

[0041]

FIG. 3 is an explanatory diagram schematically showing a cross section of the high-frequency power amplifier 100 shown in FIG. 2. As shown in FIG. 3, in the high-frequency power amplifier 100, the upper layer metal 102 is thinned out in a predetermined range, and the emitter wiring is connected from the lower layer metal 101 to the area where the upper layer metal 102 is thinned. is pulled out to the height of the upper metal 102. Of course, the size and width of each metal shown in the drawings are not limited to those shown in the drawings.

[0042]

Furthermore, as shown in FIG. 3, in the high-frequency power amplifier 100, the emitter wiring that is drawn out to the height of the upper metal 102 is drawn out so that it is directly above the back via 105 formed in the semiconductor substrate 110. It is done.

[0043]

2 and 3, the upper layer metal 102 is thinned out to a predetermined range, and an emitter wiring is connected from the lower layer metal 101 to the area where the upper layer metal 102 has been thinned out. By drawing up to the height of 102), the high-frequency power amplifier 100 shown in FIGS. 2 and 3 can suppress the parasitic capacitance between the emitter and the collector.

[0044]

Then, the high-frequency power amplifier 100 shown in FIGS. 2 and 3 thins out the upper layer metal 102 within a predetermined range, and supplies power from the lower layer metal 101 to the area where the upper layer metal 102 has been thinned out. By leading the emitter wiring to the height of the upper metal 102, the heat generated by the bipolar transistor formed in the bipolar transistor pattern area 103 is more efficiently dissipated compared to the high frequency power amplifier 10 shown in FIG. It becomes possible to release it to the outside.

[0045]

Furthermore, the high-frequency power amplifier 100 shown in FIGS. 2 and 3 forms an emitter wiring that extends to the height of the upper metal 102 so that it is located directly above the back via 105 formed on the semiconductor substrate 110. I'm doing it. By forming the emitter wiring in this way, the high frequency power amplifier 100 shown in FIGS. 2 and 3 can emit heat generated by the bipolar transistor formed in the bipolar transistor pattern area 103 to the back via 105. It becomes.

[0046]

Therefore, the high-frequency power amplifier 100 shown in FIGS. 2 and 3 is more efficient in dissipating heat generated by the bipolar transistor formed in the bipolar transistor pattern area 103 when compared to the high-frequency power amplifier 10 shown in FIG. 1. This makes it possible to release it to the outside.

[0047]

Shows another example of a high-frequency power amplifier. FIG. 4 is an explanatory diagram schematically showing a cross section of the high-frequency power amplifier 100. Shown in FIG. 4 is a pad 111 disposed on the emitter wiring of the high-frequency power amplifier 100 shown in FIG. 3, which extends to the height of the upper metal 102. Of course, the size and width of each metal shown in the drawings are not limited to those shown in the drawings.

[0048]

The high-frequency power amplifier 100 shown in FIG. 4 connects a plurality of pads 111 formed on the emitter wiring extending to the height of the upper metal 102 with, for example, a wire bond 112, Compared to the high-frequency power amplifier 100 shown in FIG. 3, it can operate in a more thermally stable manner.

[0049]

Shows another example of a high-frequency power amplifier. FIG. 5 is an explanatory diagram schematically showing a cross section of the high-frequency power amplifier 100. Shown in FIG. 5 is a metal wiring 121 disposed further above the emitter wiring of the high-frequency power amplifier 100 shown in FIG. 3, which is extended to the height of the upper metal 102. Of course, the size and width of each metal shown in the drawings are not limited to those shown in the drawings.

[0050]

The high-frequency power amplifier 100 shown in FIG. 5 is compared with the high-frequency power amplifier 100 shown in FIG. 3 by connecting emitter wires drawn out to the height of the upper metal 102 through metal wires 121. When this is done, it can operate in a more thermally stable manner.

[0051]

Next, a configuration example of a wireless communication device including the high-frequency power amplifier 100 according to an embodiment of the present invention will be described. FIG. 6 is an explanatory diagram showing an example of the configuration of a wireless communication device 1000 including a high-frequency power amplifier 100 according to an embodiment of the present invention.

[0052]

The wireless communication device 1000 shown in FIG. 6 includes a synthesizer 1010, a modulation circuit 1020, a high-frequency amplifier (1030, 1070), a filter (1040, 1080), an isolator (1050), a duplexer (1060), and a demodulation circuit. It is composed of a furnace 1090 and an antenna 1100. As the high-frequency amplifiers 1030 and 1070, the high-frequency power amplifier 100 according to an embodiment of the present invention is provided.

[0053]

The synthesizer 1010 outputs a signal used for modulation of a transmission signal in the modulation circuit 1020 and demodulation of a reception signal in the demodulation circuit 1090. The modulation circuit converts the supplied transmission signal into a transmission signal with a predetermined transmission frequency. The high frequency amplifier 1030 amplifies the output signal of the modulation circuit 1020. The filter 1040 is composed of, for example, a band-pass filter and extracts a signal in the transmission wave band from the high-frequency signal amplified by the high-frequency amplifier 1030. The isolator 1050 supplies the output signal of the filter 1040 to the duplexer 1060 in one direction.

[0054]

The duplexer 1060 has three terminals: a terminal connected to the output terminal of the isolator 1050, a terminal connected to the input terminal of the high-frequency amplifier 1070, and a terminal connected to the antenna 1100.

[0055]

The high-frequency amplifier 1070 amplifies the signal received by the antenna 1100 and output from the duplexer 1060. The filter 1080 is composed of, for example, a band-pass filter and extracts a signal in the transmission wave band from the output signal of the high-frequency amplifier 1070. The demodulation circuit 1090 demodulates the signal by mixing the signal extracted by the filter 1080 with the local oscillation signal supplied from the synthesizer 1010.

[0056]

The wireless communication device including the high-frequency power amplifier 100 according to an embodiment of the present invention is not limited to this example. If a high-frequency power amplifier that amplifies signals in the microwave band is used, applications other than those shown in FIG. 6 are possible. A wireless communication device equipped with a high-frequency power amplifier 100 according to an embodiment of the present invention can operate at low voltage, improve efficiency, and achieve miniaturization and weight reduction.

[0057]

<3. Summary>

As described above, according to one embodiment of the present invention, the upper layer metal 102 is thinned out to a predetermined range, and an emitter wiring is connected from the lower layer metal 101 to the area where the upper layer metal 102 is thinned. A high frequency power amplifier (100) is provided that extends to the height of the upper metal (102).

[0058]

The high-frequency power amplifier 100 according to an embodiment of the present invention thins out the upper layer metal 102 within a predetermined range and adds the lower layer metal 101 to the area where the upper layer metal 102 has been thinned out. By leading the emitter wiring from there to the height of the upper metal 102, it becomes possible to efficiently dissipate heat generated by the bipolar transistor formed in the bipolar transistor pattern region 103 to the outside.

[0059]

In addition, in the above embodiment, an example is shown in which the emitter wiring is a lower layer metal and the collector wiring is an upper layer metal, but the present invention is not limited to this example. The collector wiring may be a lower metal layer, and the emitter wiring may be an upper metal layer.

[0060]

Although preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that those skilled in the art in the technical field to which the present invention pertains can imagine various changes or modifications within the scope of the technical idea described in the patent claims, and these are also: Naturally, it is understood to fall within the technical scope of the present invention.

[0061]
10: High frequency power amplifier
11: Lower metal
12: Upper metal
13: Bipolar transistor pattern area
14: base
100: High frequency power amplifier
101: Lower metal
102: Upper metal
103: Bipolar transistor pattern area
104: base
105: Back Beer
110: Semiconductor substrate
111: pad
112: wire bond
121: metal wiring
1000: wireless communication device
1010: synthesizer
1020: Modulation circuit
1030: High frequency amplifier
1040: Filter
1050: Isolator
1060: Duplexer
1070: High frequency amplifier
1080: Filter
1090: demodulation circuit
1100: Antenna

Claims (7)

A lower metal layer on which the emitter or collector is wired,
An upper metal layer is formed on the lower metal layer and a collector or emitter is wired,
The upper layer metal is thinned out in area, and the wiring of the lower layer metal is drawn into the area where the upper layer metal was thinned,
A high-frequency amplifier circuit characterized in that pads are formed on wiring extending from the lower metal layer, and the pads are connected to each other. According to paragraph 1,
A high-frequency amplifier circuit, characterized in that the wiring drawn from the lower metal is located on the ground back via. According to paragraph 1,
A high-frequency amplifier circuit, characterized in that the wiring drawn from the lower layer metal is arranged in an area surrounded at least three ways by the thinned upper layer metal. According to paragraph 1,
A high-frequency amplifier circuit, characterized in that the wiring drawn from the lower metal layer extends to the height of the upper metal layer. According to paragraph 1,
A high-frequency amplifier circuit characterized in that the pads are connected by wire bonds. According to paragraph 1,
A high-frequency amplifier circuit characterized in that the pads are connected with metal wiring. A communication device comprising the high-frequency amplifying circuit according to any one of claims 1 to 6.

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