JP2002185068A - Package for storing semiconductor elements - Google Patents

Abstract

(57) [Problem] To reduce reflection loss generated in a transmission line even when the frequency of a high-frequency signal input / output to / from a semiconductor element increases. SOLUTION: A base 1 having a mounting portion 1a on which an optical semiconductor element 7 and a circuit board 9 are mounted via a mounting base 8, is attached on the upper surface so as to surround the mounting portion 1a. Metal frame 2 having through hole 2a formed in side portion, cylindrical outer conductor 3a
And a center conductor 3c disposed substantially at the center axis thereof, and an insulator 3b interposed therebetween so that both ends of the center conductor 3c protrude. A coaxial connector 3 for connecting the center conductor 3c is provided.
The inner tip is substantially flush with the inner surface of the frame 2, the central conductor 3c and the circuit board 9 are electrically connected via a plate-shaped metal piece 10, and the through-hole 2a is formed in the metal piece 10. The width increases from the end to the inner surface of the frame 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device housing package for housing various optical semiconductor devices operating at a high frequency such as optical communication, microwave communication, and millimeter wave communication.

[0002]

2. Description of the Related Art Among conventional semiconductor element housing packages (hereinafter, referred to as semiconductor packages) for housing various semiconductor elements operating at a high frequency such as optical communication, microwave communication or millimeter wave communication, they are used in the optical communication field. FIG. 5 is a cross-sectional view of the optical semiconductor package to be obtained, and FIG. 6 is an enlarged cross-sectional view of the periphery of the coaxial connector.

As shown in these drawings, an optical semiconductor package is generally provided with an optical semiconductor element 107 such as an LD (semiconductor laser) or a PD (photodiode) on a top surface via a mounting base 108. It has a mounting portion 101a and has a base 101 made of a metal material such as an iron (Fe) -nickel (Ni) -cobalt (Co) alloy or a copper (Cu) -tungsten (W) alloy. Further, it is joined to the upper surface of the base 101 via a brazing material such as silver brazing so as to surround the mounting portion 101a, and the optical semiconductor element 10
A through-hole 102a for fitting a coaxial connector 103 (also referred to as a glass bead terminal) for electrically connecting the optical semiconductor device 7 to an external electric circuit (not shown) is formed. There is a frame body 102 made of a metal material such as an Fe-Ni-Co alloy, in which a through-hole 102b as an optical transmission path for coupling is formed.

[0004] The through hole 1 as an optical transmission path of the frame 102 is
02b, an optical isolator 112 for preventing return light and an optical fiber 113 are formed of a metal material such as an Fe-Ni-Co alloy or an Fe-Ni alloy which approximates the thermal expansion coefficient of the frame 102. A cylindrical member for fixing a metal outer conductor 111 bonded with a resin adhesive or the like, and a translucent member 105 made of amorphous glass or the like and functioning as a condenser lens and having a function of closing the inside of the optical semiconductor package. The fixing member 104 is joined with a brazing material such as silver brazing.

The fixing member 104 and the metal outer conductor 111 have their respective end faces fixed by YAG laser welding or the like, while the fixing member 104 and the light transmitting member 105 are fixed.
Is fixed by attaching to a plating layer formed on the inner peripheral surface of the fixing member 104 via a low melting point brazing material such as gold (Au) -tin (Sn) alloy solder.

[0006] The coaxial connector 103 is made of Fe-Ni.
A cylindrical outer conductor (holder) 103a made of a metal material such as a Co alloy and brazed to the inner peripheral surface of the through hole 102a with a low melting point brazing material such as Au-Sn alloy solder; It is composed of a filled insulator 103b such as borosilicate glass and a center conductor (metal terminal) 103c mounted on the center axis of the outer conductor 103a and conducting inside and outside of the optical semiconductor package.

The coaxial connector 103 includes a central conductor 103c through which a high-frequency signal is transmitted, an outer peripheral portion thereof, that is, an outer peripheral conductor 103a made of a metal material, and a through hole 1c.
The inner peripheral surface 02a has a coaxial structure that allows impedance matching when transmitting a high-frequency signal.

The electrical connection between the coaxial connector 103 and the optical semiconductor element 107 is made by connecting the central conductor 103c inside the frame 102, the central conductor 103c and the through hole 1c.
The metallized metal layer 109a, which is a microstrip line formed on the upper surface of the circuit board 109 so as to have the same impedance as the inner peripheral surface of the substrate 02a, is connected to a low melting point brazing material such as tin (Sn) -lead (Pb) solder. And the metallized metal layer 109a and the optical semiconductor element 107 are connected by bonding wires 114.

In such an optical semiconductor package, a mounting base 108 on which an optical semiconductor element 107 and a circuit board 109 for impedance matching and the like are mounted is mounted via an adhesive such as a resin adhesive or a brazing material. After fixing, the center conductor 10
3c and metallized metal layer 1 on the upper surface of circuit board 109
09a with a low melting point brazing material such as Sn-Pb solder, and the optical semiconductor element 107 and the metallized metal layer 109a are electrically connected with a bonding wire 114. Thereafter, the optical isolator 112 and the optical fiber 113 are connected.
Is fixed to the fixing member 104, and the lid 106 is attached to the upper surface of the frame 102 by seam welding, brazing, or the like, whereby an optical semiconductor device as a product is obtained.

In such an optical semiconductor device, for example, the optical semiconductor element 107 is optically excited by a high-frequency signal supplied from the outside, and the excited light such as laser light is transmitted through the light transmitting member 105.
To the optical fiber 113 via the optical fiber 113
By transmitting the signal inside, it functions as a photoelectric conversion device that can transmit a large amount of information at high speed, and is often used in the field of optical communication and the like.

[0011]

However, in the above-mentioned conventional optical semiconductor package, if the frequency of the input / output high-frequency signal becomes high, the central conductor 103c inside the frame 102 does not have a coaxial structure. Is very large, and the through-hole 10
The central conductor 103c and the metallized metal layer 109 inside 2a
The gap of the impedance generated between a and a becomes large. Further, the reflection loss caused by the change in the propagation mode of the high-frequency signal transmitted via the central conductor 103c and the metallized metal layer 109a becomes so large that the operability of the optical semiconductor element 107 cannot be ignored.

Accordingly, the present invention has been completed in view of the above problems, and an object of the present invention is to reduce the impedance gap generated in a transmission line for transmitting a high-frequency signal so as to match the impedance and to reduce the impedance of the high-frequency signal. It is an object of the present invention to improve the operability of an optical semiconductor element by smoothly inputting / outputting a high-frequency signal to / from an optical semiconductor package by extremely reducing reflection loss caused by a sudden change in a propagation mode.

[0013]

According to the present invention, there is provided a semiconductor device housing package, comprising: a base having a mounting portion on which a semiconductor element and a circuit board are mounted via a mounting base; A metal frame attached to surround the mounting portion and having a through hole formed in a side portion thereof, a cylindrical outer conductor, and a center conductor disposed on a substantially central axis of the outer conductor, and A coaxial connector that is interposed therebetween and is made of an insulator provided so that both ends of the center conductor protrude, and is fitted into the through hole to electrically connect the circuit board and the center conductor. In the package for accommodating a semiconductor element described above, the coaxial connector is provided such that a tip of the center conductor inside the frame is substantially flush with an inner surface of the frame, and the center conductor and the circuit board are arranged in a line. Sheet metal It is electrically connected via,
Further, the width of the through hole is increased from a position corresponding to an end of the metal piece to an inner surface of the frame.

According to the present invention, the transmission through the center conductor of the coaxial connector, the metal piece, and the metallized metal layer on the upper surface of the circuit board even if the frequency of the high-frequency signal input / output to / from the optical semiconductor package is increased. The impedance can be matched by suppressing a sudden change in the impedance on the road. In addition, the change in the propagation mode of the high-frequency signal in this transmission path can be moderated. As a result, the reflection loss occurring in the transmission line when transmitting the high-frequency signal can be extremely reduced, and the input and output of the high-frequency signal between the optical semiconductor element and the external electric circuit can be performed smoothly.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An optical semiconductor package, which is a kind of the semiconductor package of the present invention, will be described in detail below. FIG. 1 is a cross-sectional view showing one embodiment of the optical semiconductor package of the present invention, and FIG. 2 is an enlarged cross-sectional view of a principal part of the through-hole and the coaxial connector of FIG.

In these figures, 1 is a base constituting the bottom of the container body, 2 is a frame for the side wall of the container body, 3 is a coaxial connector which is an input / output terminal for high-frequency signals, and 4 is a translucent member 5. And a cylindrical fixing member for mounting and fixing the metal outer conductor 11, 5 is a translucent member, 6 is a lid, 7 is LD, PD
And the like. The base 1, the frame 2, the coaxial connector 3, the fixing member 4, the translucent member 5, and the lid 6 basically constitute a container for housing the optical semiconductor element 7 therein.

As in the prior art, an optical isolator 12 and an optical fiber 13 are provided on the outer end face of the fixing member 4.
Is bonded to the metal outer conductor 11 with a resin adhesive or the like.
It is fixed by AG laser welding or the like.

The substrate 1 of the present invention functions as a support member for supporting the optical semiconductor element 7 and a heat radiating plate for dissipating heat generated from the optical semiconductor element 7. The device 7 has a mounting portion 1 a on which the device 7 is mounted via a mounting base 8. In this mounting portion 1a,
The mounting base 8 is adhered and fixed via a low melting point brazing material such as Sn-Pb solder, and the heat generated from the optical semiconductor element 7 is transmitted through the low melting point brazing material, thereby improving the efficiency to the outside. It is well diffused, and the operability of the optical semiconductor element 7 is improved.

The substrate 1 is made of an Fe—Ni—Co alloy or C
It is made of a metal material such as a u-W alloy, and is manufactured into a predetermined shape by subjecting the ingot to a conventionally known metal working method such as rolling or punching. In addition, a metal having excellent corrosion resistance and excellent wettability with a brazing material on its surface, specifically, a Ni layer having a thickness of 0.5 to 9 μm and a thickness of 0.5 to 9
If a μm Au layer is sequentially deposited by plating,
The substrate 1 can be effectively prevented from being oxidized and corroded, and the optical semiconductor element 7 can be firmly adhered and fixed on the upper surface of the substrate 1 via the mounting base 8. Therefore,
0.5 to 9 μm on the surface of the substrate 1 manufactured in a predetermined shape
It is preferable to apply a metal layer such as a Ni layer or a 0.5 to 9 μm Au layer by a plating method.

The mounting base 8 is made of silicon (S
i) or a metal material with high thermal conductivity such as Cu-W alloy
For transmitting heat from the optical semiconductor element 7 to the base 1
As well as setting its height as appropriate
As a result, the optical axes of the light transmitting member 5 and the optical semiconductor element 7 are aligned.
It has the function of adjusting In addition, on the upper surface,
Metallized metal layer 9a is formed as transmission line for wave signal
Alumina (Al _TwoO_Three) Ceramics and other ceramics
Circuit board 9 for impedance matching etc.
Joined.

The metallized metal layer 9a is a circuit board 9 made of a metal paste obtained by adding an organic solvent and a solvent to a powder of molybdenum (Mo), manganese (Mn), tungsten (W) or the like. It is formed by printing and applying a predetermined pattern on a ceramic green sheet in advance by a conventionally known screen printing method, followed by sintering.

Further, the metallized metal layer 9a is a microstrip line formed so as to have the same impedance as that generated inside the center conductor 3c and the through hole 2a, and is electrically connected by the optical semiconductor element 7 and the bonding wire 14. Connected to. Also, the conventional center conductor 103c
The central conductor 3c inside the frame 2 is formed by using a metal piece 10 that is close to the magnitude of the electric field generated in the metallized metal layer 9a with respect to the electric field generated in a portion protruding inside the frame 102 (FIG. 5). And metallized metal layer 9a are electrically connected. As a result, a connection portion between the center conductor 3c and the metal piece 10,
The change in the electric field generated at the connection between the metal piece 10 and the metallized metal layer 9a is moderated to suppress a rapid change in impedance, thereby reducing the reflection loss of the transmission line for transmitting the high-frequency signal.

The metal piece 10 has a substantially rectangular cross section as viewed from the side or a tapered shape tapering toward the metallized metal layer 9a.
If it is less than 10 μm, manufacturing becomes difficult, and if it exceeds 100 μm, the reflection loss of a high-frequency signal becomes very large.

The metal piece 10 has a substantially rectangular planar shape or a tapered shape tapered toward the metallized metal layer 9a, and the width of the narrowest portion is set to the center conductor 3c, Sn-Pb is applied to the metallized metal layer 9a.
It is sufficient that the width is such that it can be firmly joined with a low melting point brazing material such as solder. On the other hand, it is sufficient that the width of the widest part is equal to or less than the diameter of the center conductor 3c.
When the diameter exceeds c, the reflection loss of the high-frequency signal becomes very large.

The metal piece 10 has an angle θ1 of 0 between the main surface and the extension of the surface of the metallized metal layer 9a.
If the angle is out of the range, the reflection loss of the high-frequency signal becomes very large. More preferably, θ1 is preferably 0 to 30 °, more preferably 10 ° or less, and more preferably 0 °.

When electrically connecting the central conductor 3c and the metallized metal layer 9a, the metal piece 10 has an F coefficient having an approximate coefficient of thermal expansion in order to effectively prevent thermal distortion thereof.
It is preferable to use a metal material such as an e-Ni-Co alloy or an Fe-Ni alloy.

A coaxial connector 3 having a function of electrically connecting the optical semiconductor element 7 to an external electric circuit and hermetically closing the inside of the optical semiconductor package is fitted to one side surface of the frame 2. Is formed, and a through hole 2b having a function of an optical transmission path for optically coupling with the optical semiconductor element 7 is formed on the opposing side surface.

The coaxial connector 3 is made of Fe-Ni-C
o made of a metal material such as an alloy.
A cylindrical outer conductor 3a brazed with a low melting point brazing material such as Sn alloy solder, an insulator 3b made of borosilicate glass or the like filled in the outer conductor 3a, and a substantially central axis of the outer conductor 3a; Center conductor 3 inserted and fixed in insulator 3b so as to be installed in
c. The coaxial connector 3 has a coaxial structure in which the outer conductor 3a made of a metal material, the inner peripheral surface of the through hole 2a, and the center conductor 3c can match the impedance when transmitting a high-frequency signal. Therefore, even if the frequency of the high-frequency signal input / output to / from the optical semiconductor package is increased, there is no portion in the center conductor 3 where impedance matching becomes difficult.

The coaxial connector 3 is fitted into the through hole 2a such that the tip of the center conductor 3c inside the frame 2 is substantially flush with the inner surface of the frame 2. The tip of the center conductor 3c is the frame 2
If it is located inside the through hole 2a from the inner surface, the through hole 2a
a It becomes difficult to match the impedance generated inside due to the shape of the inner peripheral surface. As a result, the reflection loss in the transmission path of the high-frequency signal of the optical semiconductor package cannot be reduced, and it is difficult to smoothly input and output the high-frequency signal.

When the tip of the center conductor 3c inside the frame 2 protrudes from the inner surface of the frame 2, the center conductor 3c inside the through hole 2a having the coaxial structure and the inner surface of the frame 2 not having the coaxial structure are formed. A gap in impedance is generated between the center conductor 3c and the protruding center conductor 3c, which makes impedance matching difficult. As a result, the reflection loss in the transmission path of the high-frequency signal increases, and the input and output of the high-frequency signal between the external electric circuit and the optical semiconductor element 7 are not performed smoothly.

The width of the through hole 2a extends from the position corresponding to the end of the metal piece 10 on the side of the center conductor 3c to the inner surface of the frame 2 as shown in FIG. Is large). As shown in the figure, when the cross section of the through hole 2a is circular and the width gradually increases toward the inner surface of the frame 2, the frame 2 is moved from a position corresponding to the end of the metal piece 10 inside the through hole 2a. D is the distance from the inner surface, that is, the tip of the center conductor 3c, r1 is the shorter distance from the center axis of the coaxial connector 3 to the base 1 or the lid 6, and the center conductor 3c inside the frame 2 to which the metal piece 10 is not connected. The radius of the portion of the through hole 2a surrounding the portion is r2, and the angle between the axial direction of the central conductor 3c and the portion (inclined surface) of the inner peripheral surface of the through hole 2a whose diameter is gradually increased is θ2. In this case, 0 ° <θ2 ≦ tan ^{− 1 1} (r1−r2) /
Preferably, d｝.

With such a configuration, the portion of the center conductor 3c to which the metal piece 10 inside the through hole 2a is not connected,
Impedance can be matched by reducing the change in impedance that occurs at the portion of the central conductor 3c to which the metal piece 10 is connected and the portion of the metal piece 10 that protrudes from the inner surface of the frame 2. As a result, the reflection loss of the transmission path for the high-frequency signal can be reduced, and the input and output of the high-frequency signal to and from the optical semiconductor element 7 can be performed efficiently and smoothly.

Also, when θ2 is θ2> tan ^{− 1 1} (r1-
In the case of r2) / d｝, although the width of the through hole 2a gradually increases from the position corresponding to the end of the metal piece 10 inside the through hole 2a toward the inner surface of the frame 2, the through hole 2a and the base 1 intersect. Otherwise, since the through hole 2a and the lid 6 intersect, it becomes difficult to match the impedance. Therefore, the reflection loss of the high-frequency signal cannot be reduced, and it is difficult to smoothly transmit the high-frequency signal.

Specifically, it is preferable to set θ2 to 30 to 70 °, in which case the reflection loss of the high-frequency signal is effectively reduced.

FIG. 3 shows an example of the embodiment of the present invention in which the width of the through-hole 2a is smaller than that of the metal piece 10 inside the through-hole 2a.
A configuration is shown in which the size gradually increases from the position corresponding to the end toward the inner surface of the frame 2. As shown in the figure, a notch 2c having a substantially uniform width is provided in the through hole 2a from the position corresponding to the end of the metal piece 10 to the inner surface of the frame 2. The width of the notch 2c is determined by the through hole 2a surrounding the portion of the central conductor 3c to which the metal piece 10 is not connected and the portion connecting the central conductor 3c to the metal piece 10 and the metal piece protruding from the inner surface of the frame 2. 1
It can be set so that the impedances respectively generated to zero are matched. As a result, even if the frequency of the high-frequency signal input / output to / from the optical semiconductor package increases, the reflection loss due to the impedance mismatch of the transmission path of the high-frequency signal can be reduced, so that the high-frequency signal can be transmitted smoothly.

Further, as shown in FIG. 4, from the position corresponding to the end of the metal piece 10 inside the through-hole 2a to the inner surface of the frame 2a, a portion where the width of the through-hole 2a gradually increases and a portion where the width becomes constant are shown. Also, the metal piece 10 protruding from the inner surface of the frame 2 and the through hole 2a surrounding the portion of the center conductor 3c to which the metal piece 10 is not connected and the portion where the metal piece 10 is connected to the center conductor 3c can be provided. Can be matched.

In addition, the frame 2 reduces the thermal strain at the time of bonding with the base 1 to strengthen the bonding, and also performs thermal expansion (shielding) of the base 1 to provide electromagnetic shielding (shielding) to the outside of the optical semiconductor package. Fe-Ni approximating coefficient
It is preferable to use a metal material such as a -Co alloy or an Fe-Ni alloy.

The frame 2 is formed into a predetermined shape by subjecting an ingot of the same material to a conventionally known metal working method such as rolling or punching as in the case of the base 1, and the surface thereof has corrosion resistance. A metal having excellent wettability with a brazing material, specifically, a Ni layer having a thickness of 0.5 to 9 μm and a thickness of 0.1 μm.
When a 5 to 9 μm Au layer is sequentially applied by plating, the oxidative corrosion of the frame 2 can be effectively prevented, and the coaxial connector 3 and the translucent member 5 are respectively provided in the through holes 2a and 2b. It can be firmly fitted and joined. Therefore, it is preferable that a metal layer such as a 0.5 to 9 μm Ni layer or a 0.5 to 9 μm Au layer is applied to the surface of the frame 2 manufactured in a predetermined shape by plating.

The outer peripheral portion of the through hole 2b is provided with an Fe—Ni—Co alloy, Fe
A metal outer conductor 1 made of a metal material such as a Ni alloy and having an optical isolator 12 for preventing return light and an optical fiber 13 functioning as an optical transmission path of an optical signal bonded with a resin adhesive;
1, and a cylindrical fixing member 4 for fixing a translucent member 5 which is made of amorphous glass and functions as a condenser lens and has a function of closing the inside of the optical semiconductor package, is joined with a brazing material such as silver brazing. .

A translucent member 5 made of amorphous glass or the like, which functions as a condenser lens and closes the inside of the optical semiconductor package, is formed on the inner peripheral portion of the fixing member 4 on the surface of the joint. 200-40 through the metallization layer
It is joined with a low melting point brazing material such as an Au-Sn alloy solder having a melting point of 0 ° C.

The translucent member 5 has a thermal expansion coefficient of 4 × 1.
^{0 - 6 ~12 × 10 - 6} / ℃ consists of sapphire (single crystal alumina) or an amorphous glass of (room temperature to 400 ° C.), spherical, hemispherical, convex lens, is a rod lens shape or the like, outside of Used as a condensing member for transmitting light such as laser light through the optical fiber 13 and inputting it to the optical semiconductor element 7 or inputting light such as laser light output from the optical semiconductor element 7 to the optical fiber 13. . The translucent member 5 is
For example, in the case of an amorphous glass having no crystal axis, a lead-based material containing silicon oxide (SiO ₂ ) or lead oxide (PbO) as a main component, or a borosilicate-based material containing boric acid or silica sand as a main component is used. Used.

Further, even if the transmissive member 5 has a different coefficient of thermal expansion from that of the frame 2, the fixing member 4 absorbs and relaxes the stress due to the difference in thermal expansion, so that the crystal axis is reduced due to the stress. It is unlikely that the alignment in a certain direction causes a change in the refractive index of light. Therefore, by using such a translucent member 5, the light coupling efficiency between the optical semiconductor element 7 and the optical fiber 13 can be increased.

The lid 6 is made of a metal material such as an Fe-Ni-Co alloy or a ceramic such as alumina ceramics, and is joined to the upper surface of the frame 2 via a low melting point brazing material such as an Au-Sn alloy solder. Or joined by a welding method such as YAG laser welding. As a result, the optical semiconductor element 7 is housed and sealed in a container as an optical semiconductor package including the base 1, the frame 2, and the lid 6, thereby obtaining an optical semiconductor device as a product.

Thus, the present invention is different from the conventional semiconductor package using the coaxial connector 103 shown in FIG. 4 in that the center conductor 3c inside the through hole 2a, the metal piece 10 protruding from the inner surface of the frame 2 and the circuit board 9 are provided. The gap of impedance generated between the upper surface and the metallized metal layer 9a can be reduced. In addition, a portion of the central conductor 3c to which the metal piece 10 is not connected in the through hole 2a, a portion of the central conductor 3c to which the metal piece 10 is connected, and the metal piece 10 protruding into the frame 2 are passed. Thus, the change in the propagation mode of the input / output high-frequency signal can be moderated.

That is, the portion of the central conductor 3c to which the metal piece 10 inside the through hole 2a is not connected is a TEM having a coaxial structure.
The TEM mode and the TE mode are mixed at the portion of the center conductor 3c where the metal piece 10 is connected, and the TE piece is gradually set to the inside of the frame 2 so that the metal piece 10 is in the TE mode. In the joint between the metal piece 10 and the metallized metal layer 9a, the TEM mode and the TE mode are mixed, and the metallized metal layer 9a is in the TEM mode. As described above, since the propagation mode is gradually matched to the TE mode toward the inside of the frame 2 at the portion where the metal piece 10 of the center conductor 3c is connected, a rapid change in the propagation mode is suppressed. Therefore, the transmission loss of the high frequency signal is reduced.

Thus, according to the present invention, even if the frequency of a high-frequency signal input / output to / from a semiconductor device increases, the impedance of the transmission path of the high-frequency signal becomes unmatched, and the reflection loss of the high-frequency signal caused by a sudden change in the propagation mode is reduced. Can be very small.

In the present invention, the frequency of the high-frequency signal is 1
GHz band of about 100 GHz, especially 10 GHz
At a frequency equal to or higher than z, the impedance and the propagation mode in which the change has been sharp can be reduced.

The present invention is not limited to the above-described embodiment, and various changes may be made without departing from the scope of the present invention.

[0049]

According to the present invention, a coaxial connector is provided in which a tip of a center conductor inside a frame is provided so as to be substantially flush with an inner surface of the frame, and the center conductor and the circuit board are plate-shaped metal pieces. In addition, the through hole has a larger width from the end of the metal piece to the inner surface of the frame, so that the impedance gap generated in the transmission path of the high-frequency signal can be reduced, The change in the propagation mode of the high-frequency signal can be moderated. As a result, even if the frequency of the high-frequency signal input / output to / from the semiconductor element increases, the reflection loss generated in the transmission path of the high-frequency signal can be extremely reduced, and the input / output of the high-frequency signal between the semiconductor element and the external electric circuit can be performed smoothly. be able to.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an example of an embodiment of a package for housing a semiconductor element of the present invention.

FIG. 2 is an enlarged sectional view of a main part of the coaxial connector of FIG. 1 and a peripheral portion thereof.

FIG. 3 is an enlarged sectional view of a main part showing an example of an embodiment of the coaxial connector of FIG. 1 and its peripheral part.

FIG. 4 is an enlarged sectional view of a main part showing another example of the embodiment of the coaxial connector of FIG. 1 and its peripheral part.

FIG. 5 is a cross-sectional view of a conventional optical semiconductor package.

FIG. 6 is an enlarged sectional view of a conventional coaxial connector of an optical semiconductor package and a peripheral portion thereof.

[Explanation of symbols]

 1: Base 1a: Mounting section 2: Frame 2a, 2b: Through hole 3: Coaxial connector 3a: Outer conductor 3b: Insulator 3c: Central conductor 7: Optical semiconductor element 8: Mounting base 9: Circuit board 10: Metal piece

Claims (1)

[Claims] A base having a mounting portion on which a semiconductor element and a circuit board are mounted via a mounting base; and a base attached to the upper surface so as to surround the mounting portion. A metal frame having a through hole formed in a side portion, a cylindrical outer conductor, a center conductor disposed on a substantially central axis of the outer conductor, and both ends of the center conductor interposed therebetween are protruded. And a coaxial connector fitted with the through-hole and electrically connecting the circuit board and the central conductor. An end of the center conductor inside the frame is provided so as to be substantially flush with an inner surface of the frame, and the center conductor and the circuit board are electrically connected via a plate-shaped metal piece. And the through hole is in front Package for housing semiconductor chip, characterized in that the width from the position corresponding to the end of the metal strip toward the inner surface of the frame is large.