JP2009207060A - High-frequency semiconductor amplifier - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-efficiency and wide-band high-frequency semiconductor amplifier capable of performing higher harmonic wave processing by adjusting higher harmonic wave impedance without using a stub. <P>SOLUTION: A high-frequency semiconductor amplifier comprises: a semiconductor amplifying element 5; a first impedance transformer 1 formed with a length that is a 1/4 wavelength of a microwave; a second impedance transformer 2 formed with a length that is the 1/4 wavelength of the microwave; a higher harmonic wave impedance adjustment line 3 for matching with impedance transformed by the first and second impedance transformers; and an element neighborhood matching circuit 4 for performing impedance transformation using an induced reactance component. The higher harmonic wave impedance adjustment line 3 impedance-converts a higher harmonic wave, and the element neighborhood matching circuit 4 impedance-converts and settles a fundamental wave so as to be matched with impedance of the semiconductor amplifying element 5, or impedance-converts and settles a higher harmonic wave so as to be close to open impedance. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a high frequency semiconductor amplifier including a semiconductor element such as a field effect transistor and a matching circuit.

  A high-efficiency amplifier can be obtained by short-circuiting or opening the harmonic impedance as means for performing efficient harmonic processing over a wide band. Generally, a method using an open-ended line or a short-circuited line (hereinafter referred to as a stub) is used. As a circuit configuration using a stub, for example, Japanese Patent Application Laid-Open No. 6-204764, FIG. 1 (see Patent Document 1) relates to a matching circuit of a high-frequency power amplifier using a semiconductor device. A harmonic processing circuit that performs the opening process is described. That is, a transmission line 4 having a 1/8 wavelength of the fundamental wave is connected to the output terminal A point 21 of the transistor 1, and a transmission line having a wavelength of 1/8 wavelength of the fundamental wave is connected in parallel to the output terminal A point. 5 is connected, and one or more types of open-end transmission lines having a quarter wavelength of odd-order harmonics are connected to the tip B thereof.

  FIG. 1 (see Patent Document 2) of Japanese Patent Laid-Open No. 2002-76802 discloses a matching circuit 141A formed on a circuit board 14A by connecting the gate pad 131 of the semiconductor element 13 and the circuit board 14A with wires 133B to 133D. Discloses a semiconductor amplifier having a pattern of a λ / 2 open stub (a short stub for a half-wave) with respect to the fundamental wave.

Japanese Patent Laid-Open No. 6-204764 (FIG. 1)

Japanese Patent Laid-Open No. 2002-76802 (FIG. 1)

  However, in the thing of patent document 1, since the matching circuit is provided via the stub in the output side of the high frequency power amplifier, the stub for harmonic processing of various electric lengths is needed, and it is in the board | substrate in a package. When installing, the package must be large enough to accommodate the stub and matching circuit, and because of the limitation of the stub placement position, a large number of stubs cannot be installed at the optimal position due to the storage space. There was a problem that it was difficult.

  Moreover, although the thing of patent document 2 provides an open stub for every cell of the gate pad 131 of the semiconductor element 13, since there exists an advantage which falls the gain of 1/2 frequency of all the cells, many open stubs are provided. There was a problem of requiring.

  The present invention has been made to solve the above-described problems, and provides a high-efficiency and wide-band high-frequency semiconductor amplifier capable of performing harmonic processing by adjusting harmonic impedance without using a stub. Objective.

  A high-frequency semiconductor amplifier according to claim 1 is disposed on the output terminal side of a semiconductor amplifying element that amplifies a microwave input from an input terminal with a predetermined microwave frequency bandwidth, and is a quarter wavelength of the microwave frequency. A first impedance transformer having a microstrip line configuration formed by the length of the first impedance transformer and the first impedance transformer disposed in front of the first impedance transformer and formed by a length of a quarter wavelength of the microwave frequency. A second impedance transformer having a microstrip line configuration wider than the impedance transformer, and a microstrip wider than the second impedance transformer that matches the impedance transformed by the second impedance transformer and the first impedance transformer. Harmonic impedance adjustment line in strip line configuration and this harmonic impedance adjustment line The output side is connected to the output side of the semiconductor amplifying element and the input side is connected to an element matching circuit for impedance conversion with an inductive reactance component, and the harmonic impedance adjustment line maintains the impedance with respect to the fundamental wave, Impedance conversion for harmonics is performed, and the near-element matching circuit performs impedance conversion so as to match the characteristic impedance of the semiconductor amplifying element for the fundamental wave and converges it, and near the open impedance for the harmonics Thus, the impedance is converted and converged.

  The high-frequency semiconductor amplifier according to claim 2 is the high-frequency semiconductor amplifier according to claim 1, wherein the inductive reactance component of the near-element matching circuit includes inductances of wires of different line types that are electrically connected via the relay plate.

  According to the high-frequency semiconductor amplifier according to claim 1, the harmonics are converged to an optimum point near the open impedance by using the transformer, the harmonic impedance adjustment line, and the element vicinity matching circuit without using the open stub or the short-circuit stub. Thus, both fundamental wave matching and harmonic processing are performed over a wide band, and a high-frequency semiconductor amplifier having a wide bandwidth and high efficiency can be configured.

  According to the high-frequency semiconductor amplifier of the second aspect, since different types of wires are used via the relay plate as the inductive reactance component of the element vicinity matching circuit, the desired inductance due to the wires is not affected by the shape of the electrode pad of the semiconductor amplifying device. Thus, there is an effect that the impedance conversion can be easily adjusted.

Embodiment 1 FIG.
The high frequency semiconductor amplifier according to the first embodiment of the present invention will be described below. FIG. 1 is a block configuration diagram of the high-frequency semiconductor amplifier according to the first embodiment. In FIG. 1, 1 is a first impedance transformer of line impedance Z1, 2 is a second impedance transformer of line impedance Z2, 3 is a harmonic impedance adjustment line of line impedance Z3, and 4 is a near-element matching having an open impedance Z4. A circuit 5 is a high-frequency amplification element for power amplification using an FET or the like.

  6 has a ground conductor (not shown) on which the first impedance transformer 1, the second impedance transformer 2, and the harmonic impedance adjustment line 3 are mounted, and one end of the element vicinity matching circuit 4 is disposed at the end. An external substrate, 7 is a semiconductor chip (element chip) as the high-frequency amplifying element 5, and 8 is a package (high-frequency package) in which the semiconductor chip 7 is accommodated and the other end of the element vicinity matching circuit 4 is disposed at the end. Reference numeral 9 denotes an input terminal (high frequency input terminal) of the high frequency package 8, and 10 denotes an output terminal (high frequency output terminal) of the external substrate 6. The first impedance transformer 1, the second impedance transformer 2, the harmonic impedance adjustment line 3, and the element vicinity matching circuit 4 are collectively referred to as an output matching circuit. In the drawings, the same reference numerals indicate the same or corresponding parts.

  Next, the line impedance will be described with reference to FIG. FIG. 2 is a diagram for explaining the line impedance and circuit impedance of the block configuration diagram of the high-frequency semiconductor amplifier shown in FIG. In FIG. 2, Γ is a circuit impedance when the output side is viewed from the high frequency amplifying element 5, Γ ′ is a circuit impedance when the output side is viewed from the harmonic impedance adjustment line 3, and Z1 to Z4 are line impedances. A reference characteristic impedance as a terminal load of the high-frequency output terminal 10 is Z0. With respect to Z0, there is a reactance component in a line formed by two types of transmission lines, a first impedance transformer 1 installed on the output terminal 10 side and a second impedance transformer 2 placed in front of the first impedance transformer 1. Impedance conversion is performed so that the circuit impedance (Γ ′) becomes Z3 when there is no change in real impedance.

  Next, in the harmonic impedance adjustment line 3 placed in front of the first impedance transformer 1 and the second impedance transformer 2, the impedance and the fundamental wave transformed by the first impedance transformer 1 and the second impedance transformer 2 are compared. Are matched as the same characteristic impedance (Z3). In this case, the impedance fluctuates because the harmonics are not matched.

  Next, the element vicinity matching circuit 4 is disposed across the external substrate 6 and the high-frequency package 8 in the first embodiment. That is, one end of the element vicinity matching circuit 4 is connected to the input of the harmonic impedance adjustment line 3, and the other end on the input side of the element vicinity matching circuit 4 is connected to the drain (D) output of the high frequency amplification element 5.

  FIG. 3 is a schematic plan view of the high-frequency semiconductor amplifier according to the first embodiment. In FIG. 3, 21 is a pattern of the first impedance transformer 1 region (microstrip pattern), 22 is a pattern of the second impedance transformer 2 region (microstrip pattern), and 23 is a pattern of the harmonic impedance adjustment line 3 region (microstrip pattern). Microstrip pattern) 24 is a pattern of the element vicinity matching circuit 4 region. 31 is a wire using an aluminum wire or a gold wire having a diameter of 15 to 20 μm that connects the drain of the semiconductor chip 7 and the other end of the element vicinity matching circuit, and 32 is a multipolar pattern or a fine wire with a hermetic seal around the terminal. A feedthrough portion on the high frequency package 8 side having high inductance using a conductor lead or the like, 33 is a connection lead formed by a thin line or pattern, and 34 is a pad region portion on the external substrate 6 side electrically connected to the lead 33. The element vicinity matching circuit 4 includes the wire 31, the feedthrough portion 32, the lead 33, and the pad region portion 34.

  The pattern length of the pattern 21 in the first impedance transformer 1 region is set to an electrical length that is ¼ of the center wavelength of the amplification band of the high-frequency amplification element 5. The pattern length of the pattern 22 in the second impedance transformer 2 region is also set to ¼ the electrical length of the center wavelength of the amplification band of the high-frequency amplification element 5, but the pattern width is the pattern of the pattern 21 in the first impedance transformer 1 region. It is set wider than the width. On the other hand, the pattern length of the pattern 23 in the high-frequency impedance adjustment circuit 3 region is set to be 1/2 electric length or longer than the center wavelength of the amplification band of the high-frequency amplification element 5, and the pattern width is the pattern of the second impedance transformer 2 region. It is set to be wider than the pattern width of 22, and the fundamental wave impedance of this transmission line is set to Z3.

  FIG. 4 is an impedance chart for explaining the loci of the fundamental wave and the harmonic impedance of the high-frequency semiconductor amplifier according to the first embodiment. In FIG. 4, numerical values 1 to 4 in the circles indicate the impedances of the first impedance transformer 1 line, the second impedance transformer 2 line, the harmonic impedance adjustment line 3, and the element vicinity matching circuit 4 line in order. The solid line arrow indicates the locus of fundamental wave impedance, and the broken line arrow indicates the locus of harmonic impedance.

  Next, the operation will be described. When the wavelength of the harmonic wave is a second harmonic wave of the fundamental wave, for example, the center frequency of the amplification band of the high frequency amplifying element 5 is the fundamental wave frequency (f0), and the second harmonic wave is the harmonic frequency (2f0), the first impedance transformer 1 Since the fundamental wave impedance transformed by the second impedance transformer 2 and the impedance of the harmonic impedance adjustment line 3 are the same, the harmonic impedance adjustment line 3 is matched to the fundamental wave and the impedance of the fundamental wave varies. Although the impedance of the harmonics is not matched, it fluctuates.

  In addition, the impedance of the second harmonic (2f0), which is the main harmonic among the harmonics, has a large spread due to the frequency of the harmonic impedance as indicated by a circle 3 in FIG.

  The wire 31, the feedthrough portion 32, the lead 33, and the pad region portion 34 of the element vicinity matching circuit 4 basically form an inductive reactance circuit, and the fundamental wave impedance converges near the optimum point regardless of the frequency. Further, the harmonic impedance converges near the optimum point near the open impedance regardless of the frequency. That is, the matching circuit impedance converges near the optimum point where the maximum efficiency of the high-frequency amplifying element 5 is obtained.

  Next, the optimum points of the fundamental wave and harmonics of the matching circuit will be described. FIG. 5 is an impedance chart for explaining details of the optimum points of the impedance chart shown in FIG. In FIG. 5, part A is the optimum point region for the fundamental wave, part B is the optimum point region for the harmonics, and Γ is the matching circuit impedance when the output side is viewed at each frequency. FL is a band lower limit frequency of the high frequency amplifying element 5, and FH is a band upper limit frequency of the high frequency amplifying element 5. FIG. 6 is a diagram for explaining the frequency characteristics of the high-frequency semiconductor element 5 as an amplifier. 5 and 6, in the vicinity of the optimum point, the matching circuit impedance changes from the low frequency to the high frequency direction as indicated by the solid arrow in the enlarged view of part A, and the optimum point also moves as indicated by the broken line arrow. To do.

  . Similarly, the matching circuit impedance changes from the low frequency to the high frequency direction as indicated by the solid line arrow in the enlarged view of part B, and the optimum point moves as indicated by the broken line arrow.

  As described above, according to the first embodiment of the present invention, the transformer, the harmonic impedance adjustment line 3 and the vicinity of the element are provided corresponding to the impedance of the high-frequency semiconductor element 5 near the optimum point impedance without using an open stub or a short-circuit stub. Harmonic processing can be performed using the matching circuit 4. In particular, since the impedance to harmonics becomes high, it becomes possible to converge harmonics near the optimum point near open impedance, and both fundamental wave matching and harmonic processing are performed in a wide band, so that high efficiency can be achieved over a wide band. A high-frequency semiconductor amplifier can be configured.

Embodiment 2. FIG.
In the first embodiment, the wire 31 is directly connected to the feed-through portion 32 in the element vicinity matching circuit 4, but in the second embodiment, a case where the wire 31 is indirectly connected will be described with reference to FIG. 7. FIG. 7 is a schematic plan view of the high-frequency semiconductor amplifier according to the second embodiment. In FIG. 7, reference numeral 35 denotes a small relay board (relay plate) that relays the wire 31, and 36 denotes a wire that has a high inductance by reducing the pitch connecting the small relay board 35 and the feedthrough portion 32. Other configurations are the same as those described in the first embodiment. In the figure, the same reference numerals as those in FIG. 3 denote the same or corresponding parts.

  According to the second embodiment, since the wire 31 and the wire 36 are connected to the feedthrough portion 32 via the small relay board 35, the inductive reactance component in the element vicinity matching circuit 4 is set higher than that in the first embodiment. The harmonic impedance can be adjusted even in the semiconductor chip 7 having a relatively high characteristic impedance such as a wide band gap (WBG) element.

Embodiment 3 FIG.
In the first and second embodiments, the semiconductor chip 7 is accommodated in the package 8 and the drain output thereof is connected to the external substrate 6. However, in the third embodiment, the semiconductor chip 7 and the matching circuit are accommodated in the package. Will be described with reference to FIG.

  FIG. 8 is a block diagram of a high-frequency semiconductor amplifier according to the third embodiment. In FIG. 8, reference numeral 80 denotes a package, and 90 denotes an internal substrate housed in a package 80 having a ground conductor by contacting the back surface with the package. The first impedance transformer 1 and the second impedance transformer other than the semiconductor chip 7 are shown. And an output matching circuit that houses the harmonic impedance adjusting line 3 and the element vicinity matching circuit 4. The operation / action is similar to that described in the first embodiment. In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding parts.

  According to the third embodiment, since the output matching circuit is configured on the internal substrate 90 side including the element vicinity matching circuit 4, it is possible to form a line impedance that matches the characteristic impedance of the semiconductor chip 7 and suppress harmonics. Is possible.

Embodiment 4 FIG.
In the third embodiment, the semiconductor chip 7 and the internal substrate 90 are separated from each other in the package 80. In the fourth embodiment, the semiconductor chip 7 and the output matching circuit are integrated and housed in the package. 9 will be used for explanation.

FIG. 9 is a block diagram of a high-frequency semiconductor amplifier according to the fourth embodiment. In FIG. 9, 81 is a package, 100 is a semiconductor chip 7 mounted in the package 81, the first impedance transformer 1, the second impedance transformer 2, the harmonic impedance adjustment line 3, and the element vicinity matching circuit 4 are integrated. An MMIC (monolithic microwave integrated circuit) integrated on a semiconductor substrate. The operation / action is similar to that described in the first embodiment. In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding parts.

  According to the fourth embodiment, since the MMIC is mounted in the package 81 including the semiconductor chip 7, an ultra-small high-frequency semiconductor amplifier can be configured.

It is a block block diagram of the high frequency semiconductor amplifier by Embodiment 1 of this invention. It is a figure explaining the line impedance and circuit impedance of the high frequency semiconductor amplifier by Embodiment 1 of this invention. 1 is a plan view of a schematic pattern of a high-frequency semiconductor amplifier according to Embodiment 1 of the present invention. It is an impedance chart explaining the locus | trajectory of the fundamental wave and harmonic impedance of the high frequency semiconductor amplifier by Embodiment 1 of this invention. It is an impedance chart of the high frequency semiconductor amplifier by Embodiment 1 of this invention. It is a figure explaining the frequency characteristic of the high frequency semiconductor amplifier by Embodiment 1 of this invention. It is the top view which carried out the pattern pattern of the high frequency semiconductor amplifier by Embodiment 2 of this invention. It is a block block diagram of the high frequency semiconductor amplifier by Embodiment 3 of this invention. It is a block block diagram of the high frequency semiconductor amplifier by Embodiment 4 of this invention.

Explanation of symbols

1 .. First impedance transformer 2.. Second impedance transformer 3. Harmonic impedance adjustment line 4 .. Element vicinity matching circuit 5 .. Semiconductor amplification element (amplification element) 6 .. External substrate 7. Chip (semiconductor chip) 8. Package (PKG)
9. ・ Input terminal (high frequency input terminal) 10. ・ Output terminal (high frequency output terminal)
21.. First impedance transformer region pattern 22. Second impedance transformer region pattern 23. Harmonic impedance adjustment line region pattern 24... Element near matching circuit region pattern 31. Feedthrough part 33 ·· Lead 34 · · Pad area 35 on the external substrate side · · Small relay board (relay plate) 36 · · Wire (high inductance wire)
80..Package (PKG) 81..Package (PKG) 90..Internal substrate 100..MMIC

Claims (2)

A semiconductor amplifying element that amplifies a microwave input from an input terminal with a predetermined microwave frequency bandwidth, and a microstrip line configuration that is arranged on the output terminal side and has a length of ¼ wavelength of the microwave frequency First impedance transformer, and a microstrip line configuration arranged in front of the first impedance transformer and wider than the first impedance transformer formed with a length of ¼ wavelength of the microwave frequency A second impedance transformer, and a harmonic impedance adjustment line having a microstrip line configuration wider than the second impedance transformer that matches the impedance transformed by the second impedance transformer and the first impedance transformer; The output side is connected to the harmonic impedance adjustment line and the input side is An element proximity matching circuit connected to the output of the semiconductor amplifying element and impedance-converting with an inductive reactance component, the harmonic impedance adjustment line maintains impedance for the fundamental wave, performs impedance conversion for the harmonic, The near-element matching circuit impedance-converts the fundamental wave so as to match the characteristic impedance of the semiconductor amplifying element and converges it, and converts the high-frequency wave to impedance and converge so that it is close to the open impedance. Semiconductor amplifier. The high frequency semiconductor amplifier according to claim 1, wherein the inductive reactance component of the near-element matching circuit includes an inductance of a wire of a different line type that is electrically connected via a relay plate.

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