JP2001189405A - High-frequency input/output terminal and package housing high-frequency semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-frequency input/output terminal having less loss over a wide frequency band of tens of GHz which is satisfactory in transmission characteristics. SOLUTION: There are provided a dielectric substrate 1, where there is a recess 3 on the lower surface and a ground conductor 4 is formed on the lower surface around the recess 3, dielectrics so bonded on the upper surface of the dielectric substrate 1 as to face the central part of the recess 3 or a wall member 2 comprising the dielectrics, a pair of line conductors 5 and 5 formed to be in a straight to each other on both sides of the wall member 2 on the upper surface of the dielectrics substrate 1, which each of tip parts face each other at both side parts of the recess 3, a ground conductor 6 in identical plane formed on both sides of the line conductors 5 and 5, and a lower surface side line conductor 8 which is so formed on the bottom surface of the recess 3 of the dielectric substrate 1 as straight with the pair of line conductors 5 and 5, while being in parallel and connected electrically to the each tip part of the pair of line conductors 5 and 5 by both ends with through-conductors 7 and 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-frequency input / output terminal used for a high-frequency input / output section of a high-frequency semiconductor element storage package and a high-frequency semiconductor element storage package using the high-frequency input / output terminal. It is.

[0002]

2. Description of the Related Art In a signal input / output portion of a high-frequency semiconductor element housing package for hermetically sealing and housing a high-frequency semiconductor element using a high-frequency signal in a microwave band or a millimeter wave band, a high-frequency transmission line is used. A structure that joins a microstrip line formed on a dielectric substrate and a strip line of a hermetic seal portion is generally used,
Through the high frequency input / output terminal having such a structure, the high frequency semiconductor element hermetically sealed and housed in the package is connected to an external electric circuit.

As such a high frequency input / output terminal, for example, Japanese Patent Application Laid-Open No. 5-183301 discloses that a line portion forming a hermetic seal portion of a package is connected to both ends of the line portion and to the outside of the package. It has an external line portion for connection and an internal line portion for connection to an internal circuit, and the length of the line portion forming the hermetic seal portion is selected to be ｎn (n is a natural number) of the signal wavelength λ. A package input / output unit for a microwave band has been proposed.

According to this, since the length of the line portion such as the strip line portion forming the hermetic seal portion is selected to be 1 / 2n of the signal wavelength λ, the external line portion and the line portion, and the internal line portion and the line portion are selected. It is possible to prevent reflection caused by the difference in the propagation mode due to the difference in shape from the part, and reflection in the case where the manufacturing accuracy is not sufficient and the dimensions are different from the design values and the characteristic impedances are different, so that the manufacturing is easy. The cost can be reduced, and reflection can be prevented to improve characteristics in the ultrahigh frequency band.

In the conventional high frequency input / output terminal having such a configuration, each line portion is formed by a metallized metal layer made of tungsten, molybdenum, or the like on a dielectric substrate made of alumina ceramic or the like, and a hermetic metal layer is formed thereon. It has been manufactured by joining an upper dielectric material constituting a seal portion, or applying a dielectric coating on a line portion of the hermetic seal portion and mounting a cap formed of the dielectric material.

However, in the conventional high frequency input / output terminal proposed in Japanese Patent Laid-Open No. 5-183301,
Since it is necessary to select the length of the strip line portion constituting the hermetic seal portion to be 1 / 2n of the signal wavelength λ, the frequency is high, for example, in a high frequency region exceeding 30 GHz (millimeter wave band). The shorter the length of the hermetic seal, the shorter the length of the hermetic seal. If the adhesive strength between the bodies is significantly reduced and delamination occurs, or if thermal stress is applied during semiconductor device mounting, cap sealing, or secondary mounting when used in a semiconductor device housing package, hermetic There is a problem that the seal of the seal portion is damaged.

In a high-frequency region such as a millimeter-wave band, the impedance of the strip line portion and the impedance of the microstrip line portion are matched, and the difference in the propagation mode of the high-frequency signal is eliminated to reduce the reflection loss. In order to suppress this, it is assumed that the width of the line conductor in the strip line portion becomes extremely small and becomes unstable, and that the length of the line conductor in the hermetic seal portion is designed to be ｎn of the signal wavelength λ. Also, since the shape of the input / output terminals is complicated when viewed three-dimensionally, the propagation mode in the strip line section and the propagation mode in the microstrip line section before and after the strip line section are likely to be substantially different due to manufacturing variations. In addition, there has been a problem that the reflection loss and the insertion loss are increased and the transmission characteristics of the high-frequency signal are likely to be deteriorated.

In order to solve such a problem of the prior art, Japanese Unexamined Patent Application Publication No. 11-74396 discloses an exploded perspective view in FIG. 8 and a sectional view in FIG. A dielectric substrate 41 made of two layers 41b and having a ground conductor 43 on the lower surface.
And a wall member 42 joined to the upper surface of the dielectric substrate 41 and made of a dielectric or a conductor, and a pair of line conductors 44 formed on both sides of the wall member 42 on the upper surface of the dielectric substrate 41 in a straight line with each other. A pair of line conductors 44, 44 are formed below and in parallel with the pair of line conductors 44, 44 between the dielectric layer 41a, 41b and the dielectric layers 41a, 41b, and both ends of the wall member 42 of the pair of line conductors 44, 44 are formed. And the inner layer line conductor 45 electrically connected by the through conductors 47, 47, respectively. The interval between the through conductors 47, 47 is selected to be one quarter of the wavelength λ of the used high frequency signal. An input / output terminal and a high-frequency semiconductor element housing package using the high-frequency input / output terminal have been proposed.

According to the input / output terminal for high frequency, the line conductor is not interposed between the dielectric substrate 41 and the wall member 42 unlike the conventional input / output terminal for high frequency. The bonding strength with 42 can be increased and the bond can be strengthened, causing delamination or when mounting the semiconductor element, cap sealing, or secondary mounting when used in a semiconductor element storage package. A high frequency input / output terminal having a highly reliable hermetically sealed structure as a hermetic seal portion is obtained, without the seal of the hermetic seal portion being damaged even when thermal stress is applied to the hermetic seal portion.

In addition, even in a high frequency region such as a millimeter wave band, since a capacitance component exists between the inner layer line conductor 45 and the ground conductor 43 and an inductance component exists in the through conductors 47, 47, inner line conductor with respect to the width W ₃ of the line conductors 44, 44 on the dielectric substrate 41 in order to match the characteristic impedance of the line conductors 44, 44 and the inner line conductor 45 on the dielectric substrate 41 suppress reflection loss 45 need not be very small as in the conventional width W ₄ of, and since the shape of the line conductor 44, 44 and the inner line conductor 45, through conductor 47 also does not complex, propagation mode due to variations in manufacturing And the transmission loss for the used high-frequency signal can be obtained.

Further, even in a high frequency region such as a millimeter wave band, by setting the interval between the two through conductors 47 to ４ of the wavelength λ of the high frequency signal to be used, one of the apparent open ends penetrates. Since it is possible to propagate the maximum power to the other line conductor 44 via the conductor 47 and the inner layer line conductor 45, the transmission characteristic of the used high-frequency signal is not deteriorated.

As a result, the adhesive strength of the wall member 42, which is a hermetic seal portion, can be improved to prevent the occurrence of delamination and damage to the seal due to thermal stress. Thus, a highly reliable high frequency input / output terminal having excellent transmission characteristics can be provided.

[0013]

However, according to the high frequency input / output terminal described in Japanese Patent Application Laid-Open No. H11-74396, the distance between the penetrating conductors 47 is four minutes of the wavelength λ of the high frequency signal used. By setting the length and width of the line conductor 44, the width of the inner layer line conductor 45, and the diameters and lengths of the through conductors 47 and 47 to optimal values, a desired specific frequency can be used. Although excellent transmission characteristics can be obtained for signals,
In a high frequency region such as a millimeter wave band, when a high-frequency signal propagates through a line conductor, the propagation of a high-frequency signal at a specific frequency (cutoff frequency) in which a mode generally called a “higher mode” occurs. Since the phenomenon of interference occurs, there is a problem that it is not possible to obtain excellent transmission characteristics over a wide frequency range, for example, a frequency band of several tens of GHz.

In a strip line or a microstrip line used in a conventional high frequency input / output terminal, such a cutoff frequency ranges from a specific frequency determined mainly by a distance between a line conductor and a ground conductor to a high frequency. It is known that the line conductor 44, the inner layer line conductor 45, and the ground conductor
In the case where the distance to the dielectric substrate 41, that is, the thickness of the dielectric substrate 41 / dielectric layer 41a is about 0.5 to 2 mm,
The cutoff frequency caused by the frequency range from several tens of GHz to a high frequency band.

In order to move the cut-off frequency to a frequency band higher than the frequency band of the used high-frequency signal, a method of shortening the distance between the line conductor and the ground conductor is generally performed. In the structure of the input / output terminal, the dielectric layer is sandwiched between the line conductor 44 / inner layer line conductor 45 and the ground conductor 43, so that it is difficult to reduce the distance. Had.

According to the conventional high frequency input / output terminal, the through conductors 47 connecting the pair of line conductors 44 on the upper surface of the dielectric substrate 41 and the inner layer line conductor 45 are formed of a pair of line conductors.
Since they are formed so as to be orthogonal to 44 and 44 and the inner-layer line conductor 45, the propagated high-frequency signal is propagated with its traveling direction changed by 90 ° at each connection part. However, the direction of the high-frequency signal
When propagating after being changed by 90 °, a part of the high-frequency signal leaks from the transmission line without changing its traveling direction by 90 ° as shown by arrows D and E in FIG. The connection between the line conductors 44 and 44 and the through conductors 47 and 47 that are exposed to the air layer with a relative dielectric constant of 1.0 is easier to propagate a substance with a higher relative dielectric constant than a substance with a low relative dielectric constant. More high frequency signals from the connection between the inner layer line conductor 45 and the through conductors 47 and 47 formed inside the dielectric substrate 41 made of alumina ceramics and the like whose relative dielectric constant is much higher than that of the air layer. Leakage has occurred, and as a result, there has been a problem that the transmission characteristics of high-frequency signals are deteriorated.

The present invention has been devised in view of the above-mentioned problems of the prior art, and has an object to achieve a low incidence loss and a low reflection loss over a wide frequency band of several tens GHz in a high frequency signal of a millimeter wave band. An object of the present invention is to provide a high-frequency input / output terminal having good transmission characteristics.

[0018]

According to the present invention, there is provided a high frequency input / output terminal comprising a dielectric substrate having a concave portion on a lower surface and a ground conductor formed on a lower surface around the concave portion, and an upper surface of the dielectric substrate. A wall member made of a dielectric or a conductor joined so as to face the central portion of the concave portion, and both ends of the wall member on the upper surface of the dielectric substrate are linearly aligned with each other. A pair of line conductors formed so as to form a ground conductor formed on both sides of each line conductor, and a pair of line conductors are formed on the bottom surface of the concave portion of the dielectric substrate in a straight line and in parallel with the pair of line conductors. It is characterized by comprising each end portion of a pair of line conductors and a lower surface side line conductor electrically connected by a through conductor.

A package for storing a high-frequency semiconductor element according to the present invention includes a substrate having a mounting portion for mounting the high-frequency semiconductor element on an upper surface, a frame joined to the substrate so as to surround the mounting portion, An input / output terminal mounting portion formed by cutting out the frame body and having a conductive bottom surface, and a high-frequency input / output terminal having the above configuration fitted to the input / output terminal mounting portion. Things.

The high-frequency semiconductor element housing package of the present invention has a concave portion on the lower surface, a ground conductor formed on the lower surface around the concave portion, and a mounting portion for mounting the high-frequency semiconductor element on the upper surface. A dielectric substrate having
A frame made of a dielectric or a conductor joined to the upper surface of the dielectric substrate so as to surround the mounting portion and partially face the center of the concave portion, and a frame made of a dielectric or a conductor on both sides of the frame on the upper surface of the dielectric substrate. In a straight line, a pair of line conductors each formed so that each end portion is opposed to both side portions of the concave portion, the same plane ground conductor formed on both sides of each line conductor, and the bottom surface of the concave portion of the dielectric substrate. It is characterized by being formed in a straight line and parallel with the pair of line conductors, and having both ends at both ends and a lower surface side line conductor electrically connected by a through conductor, respectively, at both ends. .

According to the high frequency input / output terminal of the present invention, ground conductors on the same plane are formed on both sides of a pair of line conductors on the upper surface of the dielectric substrate, and the degree of freedom in designing the distance between the line conductor and the ground conductor is increased. By increasing the distance, it is possible to shift the cutoff frequency generated due to the “higher mode” to a frequency higher than the frequency of the high-frequency signal used by shortening the distance between the line conductor and the ground conductor on the same plane. There is little loss over a wide frequency band of several tens of GHz, and the high frequency input / output terminal has good transmission characteristics.

Further, according to the high frequency input / output terminal of the present invention, the lower surface side line conductor is formed on the bottom surface of the concave portion provided on the lower surface of the dielectric substrate, so that the traveling direction of the high frequency signal is changed by 90 °. The connection between the side line conductor and the through conductor is exposed to the air layer, whose relative dielectric constant is much lower than that of the dielectric substrate, making it difficult for high-frequency signals to propagate. Leakage can be greatly reduced, and as a result, a high frequency input / output terminal with low incidence loss and low reflection loss and little deterioration in transmission characteristics can be obtained.

According to the package for accommodating a high-frequency semiconductor element of the present invention, the high-frequency input / output terminal is fitted to the input / output mounting portion of the package to form an input / output terminal, or the package is mounted on the dielectric substrate of the package. Since this high frequency input / output terminal is integrally formed as an input / output terminal, a loss is small over a wide frequency band of several tens of GHz, and a high frequency semiconductor element housing package having good transmission characteristics is provided. Can be.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a sectional view showing an example of an embodiment of a high frequency input / output terminal according to the present invention. In FIG. 1, reference numeral 1 denotes a dielectric substrate, and 2 denotes a wall member. These components constitute a hermetic seal portion (airtight seal portion) of a signal input / output portion of the high-frequency semiconductor element storage package. FIG. 2 is an exploded perspective view of the high frequency input / output terminal shown in FIG.

The dielectric substrate 1 in this embodiment is formed by laminating two dielectric layers 1a and 1b,
The lower surface has a concave portion 3.

The dielectric substrate 1 is made of a ceramic material such as an aluminum oxide sintered body or a mullite sintered body, or a resin-based material such as Teflon (PTFE), glass epoxy, or polyimide, having a size of several mm. It is in the shape of a substantially square plate with corners. For example, if it is made of an aluminum oxide-based sintered body, a suitable organic binder and solvent are added to and mixed with raw material powders of aluminum oxide, silicon oxide, magnesium oxide, calcium oxide, and the like. It is formed into a ceramic green sheet by adopting a well-known doctor blade method, and then the ceramic green sheet is appropriately punched, laminated, and fired at a high temperature. Is done.

On the upper surface of the dielectric substrate 1, a wall member 2 made of a dielectric or a conductor is adhered and fixed so as to face the central portion of the concave portion 3. When the wall member 2 is made of a dielectric material, a ceramic green sheet is obtained by the same method using the same material as the dielectric substrate 1 and the ceramic green sheet is subjected to an appropriate punching process and the dielectric substrate 1 It is laminated and fired with the ceramic green sheet to be bonded to the upper surface of the dielectric substrate 1. When the wall member 2 is made of a conductor, an Fe-Ni-Co alloy, an Fe-Ni alloy such as an Fe-Ni42 alloy, oxygen-free copper, aluminum, stainless steel, a Cu-W alloy, a Cu-Mo alloy, etc. Is formed into a predetermined shape by applying a conventionally known metal working method such as a rolling process or a punching method to the ingot (a lump), and an adhesive such as brazing material, resin, glass or the like is formed on the upper surface of the dielectric substrate 1. To be fixed.

Further, on the dielectric substrate 1, a ground conductor 4 is formed on the lower surface around the recess 3, and on the upper surface, a pair of line conductors 5 Ground conductors 6.6 on the same side on both sides of a pair of line conductors 5.5
Are formed on the bottom surface of the concave portion 3 in a straight line and in parallel with the pair of line conductors 5.
7, a lower surface side line conductor 8 electrically connected to the lower surface side conductor 8 is formed.

The line conductor 5 and the through conductor 7
A transmission line of a high-frequency input / output terminal is formed by the lower-side line conductor 8, the through conductor 7, and the line conductor 5, and an electrode of a high-frequency semiconductor element (not shown) is connected to one of the line conductors 5 via a bonding wire, for example. Connected electrically
The other line conductor 5 is electrically connected to a wiring conductor of an external electric circuit board (not shown) via, for example, a bonding wire.

In this embodiment, the same plane ground conductor 6 is used.
Are formed continuously and integrally so as to surround the pair of line conductors 5, 5, so that a better grounding state can be obtained. And is adhesively fixed to the upper surface of the dielectric substrate 1 through the substrate.

The ground conductor 4, the line conductor 5, the same plane ground conductor 6, the through conductor 7, and the lower line conductor 8 are made of a metal material for a high-frequency line conductor, for example, Cu or MoMn + Ni + A.
u, W + Ni + Au, Cr + Cu, Cr + Cu + Ni +
Au, Ta ₂ N + NiCr + Au, Ti + Pd + Au,
It is made of NiCr + Pd + Au or the like, and is formed by a conventionally known thick film printing / metallizing method or various thin film forming methods or plating methods. The tungsten paste obtained by the addition and mixing is printed and coated in a predetermined pattern on a ceramic green sheet serving as the dielectric substrate 1 by a conventionally known screen printing method, and then fired together with the ceramic green sheet serving as the dielectric substrate 1. Thus, a predetermined pattern is formed. In order to prevent the metallized layer from being oxidized and corroded and to improve the bonding property with the bonding wire, the exposed surface is usually plated with nickel having a thickness of about 1 to 20 μm and 0.1 to 0.1 μm.
Gold plating having a thickness of about 3 μm is sequentially applied.

It should be noted that these thicknesses and widths, for example line width W ₁ of the conductor 5, diameter of the width W ₂ of, through conductors 7 length, through conductors 7 of the lower surface side line conductor 8, the frequency of the use frequency signal It is appropriately set in consideration of the impedance and characteristic impedance matching.

The width W _{1 of the} pair of line conductors 5 and the width W ₂ of the lower-side line conductor 8 are determined in accordance with the required specifications so that the width W ₂ matches the ideal characteristic impedance. Usually, it is appropriately set as W ₁ ≧ W ₂ .

The through conductor 7 is preferably a so-called via-hole conductor whose inside is filled with a conductor in view of high-frequency characteristics, but may be a so-called through-hole conductor whose inside is not completely filled. The shape may be rectangular or elliptical in addition to circular.

In the present invention, the dielectric substrate 1
Are formed on both sides of the pair of line conductors 5 on the upper surface of the line conductor 5, the same plane ground conductor 6 as the line conductor 5 is formed.
The degree of freedom in designing the distance between the line conductor 5 and the ground conductor 6 on the same plane is shortened by increasing the degree of freedom in design.
It is possible to shift the cut-off frequency generated due to the frequency to a frequency higher than the frequency of the used high-frequency signal, reduce loss over a wide frequency band of several tens of GHz in the millimeter wave band, and obtain a high-frequency signal having good transmission characteristics. Input / output terminals can be obtained.

When the distance between the line conductor 5 and the ground conductor 6 is less than 0.05 mm, the distance between the adjacent line conductors 5 and the ground conductor 6 is extremely small. Insufficient electrical insulation and short circuits are likely to occur. Therefore, the distance between the line conductor 5 and the same-plane ground conductor 6 is preferably 0.05 mm or more.

In the present invention, the lower-side line conductor 8 is formed on the bottom surface of the concave portion 3 provided on the lower surface of the dielectric substrate 1 so that the traveling direction of the high-frequency signal can be changed by 90 °. And the through conductor 7 is exposed to an air layer whose relative dielectric constant is much lower than that of the dielectric substrate 1 and in which a high-frequency signal is difficult to propagate. Leakage can be greatly reduced, and as a result, a high frequency input / output terminal with low incidence loss and low reflection loss and little deterioration in transmission characteristics can be obtained.

The concave portion 3 has a shape of approximately square, circular, elliptical, oval, or the like having a size of several mm square, and exposes the inner layer line conductor 8 to the air layer on the lower surface side of the dielectric substrate 1. It is provided for the purpose. If the distance between the side wall of the concave portion 3 and the inner layer line conductor 8 is less than 0.1 mm, the high-frequency signal leaked from the transmission line tends to flow to the dielectric substrate 1. There is a tendency that the thickness of the thin region increases and the strength of the dielectric substrate 1 decreases. Therefore, the distance between the side wall of the concave portion 3 and the inner layer line conductor 8 is preferably in the range of 0.1 to 2 mm.

Thus, according to the high-frequency input / output terminal of the present invention, the high-frequency input / output terminal of the millimeter wave high-frequency signal has low incidence loss and low reflection loss over a wide frequency band of several tens of GHz, and has good transmission characteristics. Terminals can be provided.

In the present invention, a cap made of a dielectric or a conductor also serving as a lid of the package may be used as the wall member 2, and the structure constituting the hermetic seal portion of the package is shown in FIGS. As shown in FIG. 2, in addition to the structure in which the wall member 2 for forming the hermetic seal portion is joined between the pair of line conductors 5 and 5, the structure using a dielectric wall when a multilayer structure is required, and the like. By a dielectric wall having a metallized metal layer for attaching a metal member thereon, by a substrate-like terminal structure having no dielectric wall on the surface of one layer or a similar wall, instead of a dielectric wall A dielectric coating, for example, an alumina coating may be applied.

Next, the package for storing a high-frequency semiconductor device of the present invention will be described in detail with reference to the accompanying drawings.

FIGS. 3 and 4 are perspective views showing an example of the embodiment of the package for housing a high-frequency semiconductor element according to the present invention.

In these figures, reference numeral 21 denotes a substrate made of a dielectric or a conductor, and has on its upper surface a mounting portion 21a for mounting a high-frequency semiconductor element (not shown). FIG. 3 shows an example in which the mounting portion 21a has a flat surface.
Is an example in which a concave portion is formed in the mounting portion 21a. Reference numeral 22 denotes a frame joined on the substrate 21 so as to surround the mounting portion 21a.
Like 21, it is made of a dielectric or a conductor.

The frame 23 is formed by cutting the frame 22.
This is an input / output terminal mounting portion whose bottom surface is made conductive. In the example of FIG. 4, the input / output terminal mounting portion 23 is formed by providing a similar notch in the substrate 21. The bottom surface of the input / output terminal mounting portion 23 is conductive when the substrate 21 and the frame 22 are made of a conductive material, but is formed by applying a conductive layer when the substrate 21 and the frame 22 are made of a dielectric material. To make it conductive. This bottom surface is grounded via the substrate 21 and the frame 22 or a ground conductor layer (not shown) formed on the substrate 21 and the frame 22.

Reference numeral 19 denotes a high-frequency input / output terminal according to the present invention having the above-mentioned structure fitted to the input / output terminal mounting portion 23, 11 being a dielectric substrate, and 12 being joined to the upper surface of the dielectric substrate 11. A wall member made of a dielectric or a conductor, 14 is a ground conductor on the lower surface of the dielectric substrate 11, 15 is a pair of line conductors formed on both sides of the wall member 12 on the upper surface of the dielectric substrate 11, Reference numeral 16 denotes a ground conductor on the same plane formed on both sides of the line conductors 15. Reference numeral 17 denotes a through conductor that electrically connects both ends of the lower-side line conductor (not shown) and both ends of the pair of line conductors 15 on both sides of the wall member 12. The ground conductor 14
Is connected to the conductive bottom surface of the input / output terminal mounting portion 23 and is grounded. FIG. 4 shows an example in which the frame 22 also serves as a wall member of the high frequency input / output terminal.

According to such a package for accommodating a high-frequency semiconductor element of the present invention, the high-frequency input / output terminal according to the present invention having the above-described structure as the structure of the high-frequency input / output terminal portion.
As a result, the semiconductor device package for high-frequency devices has a small loss over a wide frequency band of several tens of GHz and has good transmission characteristics.

Then, the line conductor 15 is connected to the terminal electrode of the high-frequency semiconductor element mounted on the mounting portion 21a and the wiring conductor of the external electric circuit via a wire, a ribbon, or the like to connect the high-frequency semiconductor element inside the package to the outside. An electric circuit is electrically connected, and an Fe-Ni-Co alloy or an Fe-Ni alloy such as an Fe-Ni42 alloy, oxygen-free copper, aluminum, stainless steel, Cu-W alloy, Cu-Mo A high-frequency semiconductor element is hermetically sealed and housed in a package by attaching a lid made of an alloy or the like with a high-melting-point metal solder such as solder, AuSn wax, or AuGe wax, or seam welding (welding). As a high-frequency semiconductor device.

The substrate 21 and the frame 22 are made of the same dielectric material as the dielectric substrate 11 of the high frequency input / output terminal 19 or the same metal as the above-mentioned frame 12 according to the specifications of the package. In this case, at least the bottom surface of the input / output terminal mounting portion 23 is made conductive.

The substrate 21 and the frame 22 are made of AgCu solder.
It is joined by a high melting point metal brazing such as AuSn brazing or AuGe brazing. Further, the high frequency input / output terminal 19 and the input / output terminal mounting portion 23 are fitted and joined by the same high melting point metal brazing.

In the present invention, the high frequency input / output terminals 19 are mounted on both sides of the substrate 21 one by one. However, if necessary, a plurality of terminals may be mounted at other positions or on one side. In this case, a plurality of input / output terminal mounting portions 23 may be provided, and a plurality of high frequency input / output terminals 19 may be mounted in parallel.

Further, the high frequency input / output terminal 19 and the wall member 22
Ground conductors may be provided on the upper surface of the wall member 22 and the side surfaces of the dielectric substrate 21 respectively.
Each ground conductor becomes an ideal ground (potential 0) and can be a shield for high-frequency signals.

FIGS. 5A and 5B are a perspective view and a sectional view showing another embodiment of the high frequency semiconductor element housing package of the present invention.

In the figure, reference numeral 30 denotes a dielectric substrate, which is made of the same material as the above-mentioned dielectric substrate 11, and has a mounting portion 30a for mounting a high-frequency semiconductor element (not shown) on its upper surface. Have. In this example, the case where the mounting portion 30a is formed in a flat shape is shown, but the mounting portion 30a may be formed in a concave shape. 33
Is a concave portion formed on the lower surface of the dielectric substrate 30, 32 is a frame body made of a dielectric or a conductive member partially joined to the upper surface of the dielectric substrate 30 so as to face the central portion of the concave portion 33, 35 is A pair of line conductors are formed on both sides of the frame 32 on the upper surface of the dielectric substrate 30 so as to be linear with each other, and each end portion is opposed to both side portions of the concave portion 33, and 36 is both sides of the line conductors 35, 35 And a high-frequency input / output terminal 39 of the dielectric substrate 30 indicated by a dotted line in FIG.
A ground conductor provided around the concave portion 33 on the lower surface of the dielectric substrate 31 that constitutes the lower surface side line conductor 40 formed on the bottom surface of the concave portion 33 in a straight line and parallel to the line conductors 35, 35, 37 Both ends of the lower-side line conductor 40 and a frame of a pair of line conductors 35
It is a through conductor that electrically connects each end of both sides of a portion corresponding to the wall member 38 constituting the high frequency input / output terminal 39 among the 32.

With such a configuration, a high-frequency wave including the dielectric substrate 31, the wall member 38, the pair of line conductors 35, 35, the same-plane ground conductor 36, the ground conductor 34, the lower-side line conductor 40, and the through conductors 37, 37 is provided. The input / output terminals 39 are integrally formed to constitute a high-frequency semiconductor element housing package of the present invention.

According to the package for housing a high-frequency semiconductor element of the present invention having the above structure, the ground conductors 36 on the same plane are formed on both sides of the pair of line conductors 35 on the upper surface of the dielectric substrate 31. The design flexibility of the distance between the line conductor 35 and the same-plane ground conductor 36 is large, and the cut-off frequency generated due to the “higher-order mode” can be reduced by shortening the distance between the line conductor 35 and the same-plane ground conductor 36. It is possible to move to a frequency higher than the frequency of the used high-frequency signal, and the loss is small over a wide frequency band of several tens of GHz in the millimeter wave band,
A high-frequency semiconductor element housing package having good transmission characteristics can be obtained.

Further, the lower surface side line conductor 40 is formed on the bottom surface of the concave portion 33 provided on the lower surface of the dielectric substrate 31 so that the traveling direction of the high-frequency signal is changed by 90 ° and the lower surface side line conductor 40 and the through conductor 37.
Since the connection portion with 37 is exposed to an air layer whose relative dielectric constant is much lower than that of the dielectric substrate 31 and does not easily transmit high-frequency signals, leakage of high-frequency signals from the transmission line is prevented. As a result, it is possible to obtain a package for housing a high-frequency semiconductor element that has low incidence loss and low reflection loss and has little deterioration in transmission characteristics.

Then, the line conductor 35 is connected to the terminal electrode of the high-frequency semiconductor element mounted on the mounting portion 30a and the wiring conductor of the external electric circuit via a wire, a ribbon, or the like to connect the high-frequency semiconductor element inside the package to the outside. An electric circuit is electrically connected, and a lid made of FeNi alloy such as FeNiCo alloy or FeNi42 alloy, oxygen-free copper, aluminum, stainless steel, CuW alloy, CuMo alloy, etc. is provided on the upper surface of the frame 32. Solder body, AuSu wax or AuGe
A high-frequency semiconductor element is hermetically sealed and accommodated in a package by being attached with a high-melting point metal such as brazing, seam welding (welding), and the like, thereby forming a semiconductor device as a product.

The dielectric substrate 30 is formed using the same dielectric as the dielectric substrate 31 of the high frequency input / output terminals 39 according to the specifications of the package. It is desirable that a ground conductor be formed on almost the entire lower surface of the dielectric substrate 30 in the same manner as the ground conductor 34 from the viewpoint that the ground conductor 34 needs to be in an ideal ground state.

The dielectric substrate 30 is formed, for example, on a ceramic green sheet that becomes the dielectric substrate 30 after firing by line conductors 35.
35, ground conductor 34, lower side line conductor 40, through conductor 37, 37
It is manufactured by printing or embedding a conductor paste serving as the same-surface ground conductor 36 in a predetermined pattern, and firing and integrating it with the dielectric substrate 30.

If the frame 32 is made of a conductor, a ceramic green sheet is formed using the same material as the dielectric substrate 30 and formed into a frame by punching.
The ceramic green sheet serving as the dielectric substrate 30 is laminated, fired, and integrated to be fixed to the dielectric substrate 30.

In the case where the frame 32 is made of a conductive material, a well-known metal working such as rolling or punching is applied to an ingot made of the same conductive material as the lid. After being formed into a predetermined shape, it is bonded and fixed to the dielectric substrate 30 via an adhesive such as brazing material, resin, glass, or the like.

In this embodiment, the portion corresponding to the wall member 38 of the high frequency input / output terminal 39 of the frame 32 is integrated with the frame 32 so that the upper surface thereof is flush with the upper surface of the frame 32. However, in this case, a lid (not shown) is provided on these upper surfaces.
Is mounted directly or via a frame-shaped metal seal or the like, so that the high-frequency semiconductor element mounted on the mounting portion 30a can be easily hermetically sealed and accommodated therein.

In this embodiment, one high frequency input / output terminal 39 is provided on each side of the dielectric substrate 30. However, if necessary, a plurality of high frequency input / output terminals may be provided at other positions or on one side. An output 39 may be provided.

Further, in the high frequency semiconductor element housing package of the present invention, the upper surface of the frame 32 corresponding to the wall member 38 of the high frequency input / output terminal 39 and the side surfaces of the wall member 32 and the dielectric substrate 30 are respectively provided. A ground conductor may be provided,
When these are provided, each ground conductor becomes an ideal ground (potential 0), and can be used as a shield for high-frequency signals.

Thus, according to the package for storing a high-frequency semiconductor element of the present invention, in the ultra-high frequency band, especially in the millimeter wave band of 30 GHz or more, the loss is small over a wide frequency band of several tens of GHz, and the high-frequency wave having good transmission characteristics is obtained. A semiconductor device housing package.

[0067]

Hereinafter, examples of the present invention will be described.

Example 1 In order to compare the present invention with a conventional high frequency input / output terminal, an analysis model having the following configuration was created, and a three-dimensional electromagnetic field simulation was performed.

The material of the dielectric substrates 1 and 41 and the wall members 2 and 42 is aluminum oxide (relative permittivity ε _r = 8.8), and the thickness of the dielectric substrates 1 and 41 is 1.0 mm (the thickness of the dielectric layer 1a is 0.
15 mm, thickness of 1b is 0.85 mm), penetrating conductors 7 and 47
The distance between peers is 1.7mm, and the diameter of through conductor 7.47 is 0.15m
m, the width of the line conductor 5.45 is 0.15 mm, and the lower side line conductor 8
Is 0.15 mm, the width of the inner layer line conductor 45 is 0.08 mm, the distance between the line conductor 5 and the ground conductor 6 is 0.075 mm, and the width and length of the concave portion 3 of the dielectric substrate 1 are 0.4 mm and 2.2 mm. Set to.

For these high frequency input / output terminals, input ports are set, and a simulation is performed for a high frequency band of 40 to 85 GHz, and a return loss (Return Lo) is performed.
ss) and insertion loss (Insertion Loss) frequency characteristics were obtained.

Regarding these results, first, the frequency characteristics of the reflection loss and the frequency characteristics of the insertion loss of the high-frequency input / output terminal according to the present invention are shown in FIGS. 6A and 6B, respectively. In these figures, the horizontal axis represents the frequency in the range of 30 to 90 GHz (unit: GHz), and the vertical axis represents the reflection loss or insertion loss (unit: dB).

From the results shown in FIG. 6, it can be seen that the high frequency input / output terminal of the present invention has good transmission characteristics with little characteristic deterioration (loss) in the high frequency band of 40 to 70 GHz.

Next, comparison of the frequency characteristics of the reflection loss and the insertion loss with respect to the conventional high-frequency input / output terminal of the comparative example is shown in FIGS. 7A and 7B, respectively.

From the results shown in FIG. 7, in this conventional high-frequency input / output terminal, characteristic deterioration (loss) occurs in a frequency band of more than 40 GHz, and good transmission characteristics are obtained over a frequency band of several tens GHz. Can not be obtained.

As described above, according to the high frequency input / output terminal of the present invention, the high frequency input / output terminal has excellent transmission characteristics with little characteristic deterioration (loss) for a high frequency signal of 40 to 80 GHz. It could be confirmed.

[0076]

According to the high frequency input / output terminal of the present invention,
A ground conductor on the same plane is formed on both sides of a pair of line conductors on the top surface of the dielectric substrate to increase the degree of freedom in designing the distance between the line conductor and the ground conductor. , It is possible to shift the cut-off frequency generated due to the “higher-order mode” to a frequency higher than the frequency of the used high-frequency signal.
It is a high frequency input / output terminal with low loss over a wide frequency band with good transmission characteristics.

According to the high frequency input / output terminal of the present invention, the lower surface side line conductor is formed on the bottom surface of the concave portion provided on the lower surface of the dielectric substrate, and the traveling direction of the high frequency signal is changed by 90 °. The connection between the side line conductor and the through conductor is exposed to the air layer, whose relative dielectric constant is much lower than that of the dielectric substrate, making it difficult for high-frequency signals to propagate. Leakage can be greatly reduced, and as a result, a high frequency input / output terminal with low incidence loss and low reflection loss and little deterioration in transmission characteristics can be obtained.

According to the high frequency semiconductor element storage package of the present invention, the high frequency input / output terminal is fitted to the input / output mounting portion of the package to form an input / output terminal, or the package is mounted on the dielectric substrate of the package. Since this high frequency input / output terminal is integrally formed as an input / output terminal, a loss is small over a wide frequency band of several tens of GHz, and a high frequency semiconductor element housing package having good transmission characteristics is provided. Can be.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of an embodiment of a high frequency input / output terminal of the present invention.

FIG. 2 is an exploded perspective view showing one example of an embodiment of a high frequency input / output terminal of the present invention.

FIG. 3 is a cross-sectional view illustrating an example of an embodiment of a high frequency input / output terminal of the present invention.

FIG. 4 is a perspective view showing an example of an embodiment of a high-frequency semiconductor element housing package according to the present invention.

FIGS. 5A and 5B are a perspective view and a sectional view, respectively, showing an example of an embodiment of a high-frequency semiconductor element housing package according to the present invention.

FIGS. 6A and 6B are diagrams showing frequency characteristics of reflection loss and insertion loss of the high frequency input / output terminal of the present invention, respectively.

FIGS. 7A and 7B are diagrams showing frequency characteristics of reflection loss and insertion loss of a high frequency input / output terminal of a comparative example, respectively.

FIG. 8 is an exploded perspective view showing an example of an embodiment of a conventional high frequency input / output terminal.

FIG. 9 is a cross-sectional view showing an example of an embodiment of a conventional high frequency input / output terminal.

[Explanation of symbols]

 1 · 11 · 31 · · · dielectric substrate 2 · 12 · 38 · · · wall member 3 · 33 · · · · · concave section 4 · 14 · 34 · · · ground conductor 5 · 15 · 35 · · · line conductor 6 ・ 16 ・ 36 ・ ・ ・ Grounding conductors on the same plane 7.17 ・ 37 ・ ・ ・ Through conductors 8 ・ 40 ・ ・ ・ ・ ・ ・ Line conductors on the bottom side 19 ・ 39 ・ ・ ・ ・ ・ ・ High frequency input / output terminals 21 ・ ・・ ・ ・ ・ ・ Substrate 22 ・ 32 ・ ・ ・ ・ ・ ・ ・ Frame 23 ・ ・ ・ ・ ・ ・ ・ I / O terminal mounting part 30 ・ ・ ・ ・ ・ ・ ・ Dielectric substrate

Claims (3)

[Claims] 1. A dielectric substrate having a concave portion on a lower surface and a ground conductor formed on a lower surface around the concave portion, and a dielectric bonded to an upper surface of the dielectric substrate so as to face a central portion of the concave portion. A wall member made of a body or a conductor, and a pair of line conductors formed on both sides of the wall member on the upper surface of the dielectric substrate in a straight line with each other so that each of the tip portions faces both side portions of the concave portion, respectively. Ground conductors formed on both sides of each line conductor, and formed on the bottom surface of the concave portion of the dielectric substrate in a straight line and parallel with the pair of line conductors, and both ends of each of the pair of line conductors are formed. A high-frequency input / output terminal comprising a tip portion and a lower-side line conductor electrically connected to each other by a through conductor. 2. A substrate having a mounting portion for mounting a high-frequency semiconductor element on an upper surface, a frame joined to the substrate so as to surround the mounting portion, and a frame formed by cutting out the frame. A package for accommodating a high frequency semiconductor element, comprising: an input / output terminal mounting portion having a conductive bottom surface; and the high frequency input / output terminal according to claim 1 fitted to said input / output terminal mounting portion. . 3. A dielectric substrate having a concave portion on the lower surface, a ground conductor formed on the lower surface around the concave portion, and a mounting portion for mounting a high-frequency semiconductor element on the upper surface, and an upper surface of the dielectric substrate A frame made of a dielectric or a conductor that is joined so as to surround the mounting portion and a part thereof faces the center portion of the concave portion, and a straight line is formed on both sides of the frame on the upper surface of the dielectric substrate. A pair of line conductors each formed so that each tip portion is opposed to both side portions of the concave portion, a same-plane ground conductor formed on both sides of each line conductor, and a bottom surface of the concave portion of the dielectric substrate A lower surface side line conductor formed in a straight line and parallel with the pair of line conductors, and both ends of which are electrically connected to each end portion of the pair of line conductors and through conductors, respectively. Semiconductor Package for element storage.