JP2002314186A - Package for storing optical semiconductor element and optical semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the airtightness of an optical semiconductor element, the light connection efficiency of the optical semiconductor element and an optical fiber, the high frequency transmission characteristic of the optical semiconductor element and an input/output terminal and heat diffusion property at the time of the operation of the optical semiconductor element. SOLUTION: A substrate 1 in a rectangular parallelepiped shape has the installation part 1a of the optical semiconductor element 5 at the base of a recessed part at an upper face, an optical fiber fixing member fitting part 1b formed form one side to the recessed part, and an input/output terminal fitting part 1c formed from the other side to the recessed part. Mo plate members 1A and Cu plate members 1B whose main face shapes are made to be recessed shapes are placed vertically and are alternately arranged in a lateral direction, and the main faces are brazed. When the thickness of the Mo plate member 1A is set to be T1, the thickness of the Cu plate member 1B to be T2 and the thickness of a soldering material layer 1C between the Mo plate member 1A and the Cu plate member 1B to be T3, T1/(T2+T3)=4 to 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor laser (L).
D), an optical semiconductor element housing package for housing an optical semiconductor element such as a photodiode (PD), and an optical semiconductor device using the optical semiconductor element housing package.

[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, microwave communication or millimeter communication are known. FIG. 3 shows a semiconductor package used for wave communication and the like.

[0003] As shown in FIG.
Generally, a field effect transistor (FET: Field:
The substrate 111 has a mounting portion 111a on which a semiconductor element 115 such as an effect transistor is mounted. Also, it is joined to the upper surface of the base 111 via a brazing material such as silver (Ag) brazing so as to surround the mounting portion 111a, and the input / output terminal mounting portion is formed by a through opening or a cutout formed in a side portion. A frame 112 having a portion 112a and made of a metal material such as an iron (Fe) -nickel (Ni) -cobalt (Co) alloy or an Fe-Ni alloy is provided. Further, an insulating material such as alumina (Al ₂ O ₃ ) ceramics or aluminum nitride (AlN) ceramics having a metallized layer 113 a fitted to the input / output terminal mounting portion 112 a and provided so as to lead inside and outside of the semiconductor package is used. Input / output terminal 113. The semiconductor package mainly includes a base 111, a frame 112, and input / output terminals 113.

[0004] The base 111 functions as a so-called heat radiating plate for efficiently transmitting heat generated during operation of the semiconductor element 115 to a heat sink portion of an external electric circuit board (not shown).
The substrate 111 is generally made of a copper (Cu) -tungsten (W) alloy, or as shown in FIG. 4, a molybdenum (Mo) plate 111A and a Cu plate 111B are alternately vertically laminated in a plurality of layers and rolled. A material made of a metal material such as a laminated material (cladding material) formed by the above method has been proposed (see Japanese Patent Application Laid-Open No. Hei 6-21287).

[0005] The laminate of the Mo plate 111A and the Cu plate 111B shown in FIG. 4 is made of Mo so that the average thermal expansion coefficient of the Mo plate 111A and the Cu plate 111B is close to that of the frame 112 and the input / output terminals 113. The thickness ratio between the plate 111A and the Cu plate 111B is appropriately set.

As shown in FIG. 5, such a semiconductor package uses a base 11 similar to the base 111,
The semiconductor element 115 is an optical semiconductor element 16 such as a semiconductor laser (LD) or a photodiode (PD).
A so-called optical semiconductor package in which an optical signal can be transmitted through the semiconductor package can also be used.

That is, the optical semiconductor package shown in FIG. 5 has a mounting portion 11a on which an optical semiconductor element 16 is mounted on the upper surface, and surrounds the base 11 having the configuration shown in FIG. 4 and the mounting portion 11a. An optical fiber fixing member mounting portion 12a formed of a through hole formed on one side and a through opening or notch formed on the other side while being joined to the upper surface of the base 11 through a brazing material such as Ag brazing. A frame 12 having an input / output terminal mounting portion 12b composed of a portion, a cylindrical optical fiber fixing member (hereinafter referred to as a fixing member) 15 fitted to the optical fiber fixing member mounting portion 12a, and an input / output terminal mounting portion 12b.
Further, a lead terminal 14 electrically connected to an external electric circuit board is joined to a metallized layer 13a formed on the upper surface of the input / output terminal 13 outside the optical semiconductor package via a brazing material such as silver brazing. .

Further, such an optical semiconductor package includes:
The optical semiconductor element 16 is accommodated, and an electrode of the optical semiconductor element 16 and the metallized layer 13a are bonded with a bonding wire (not shown).
After being electrically connected by, sealing with the lid 17 and
By joining an optical fiber 19 fixed to an optical fiber support member (hereinafter, referred to as a support member) 18 to the fixing member 15 via the support member 18, the optical semiconductor element 16 and the optical fiber 19 are optically coupled. , A so-called optical semiconductor device.

This optical semiconductor device has a function of causing the optical semiconductor element 16 to input / output a high-frequency signal (electric signal) to / from an external electric circuit board, and the optical semiconductor element 16 to transmit an optical signal to / from the optical fiber 19. It has a function to perform input and output. That is, this optical semiconductor device functions as a photoelectric conversion device, and is widely used in the optical communication field.

[0010]

However, in the prior art shown in FIG. 5, when the frame 12 bonded to the upper surface of the base 11 is not at a predetermined position on the upper surface of the base 11, that is, the bonding position of the frame 12 If they are misaligned, there is a problem that a gap is formed between the base 11 and the frame 12 and the airtightness of the optical semiconductor element 16 is impaired.

When the base 11 and the frame 12 are misaligned, if the optical semiconductor element 16 is mounted and fixed on the mounting portion 11a so as to be parallel to the end face of the base 11, It is very difficult to adjust the optical axis of the optical fiber 19 fixed to the fixing member 15 so as to extend in a direction substantially perpendicular to one side (one side) of the frame 12.
That is, the efficiency of light coupling between the optical semiconductor element 16 and the optical fiber 19 is reduced, so that the optical semiconductor element 16 has a problem such as malfunction.

Further, in such a conventional configuration, the electrodes of the optical semiconductor element 16 and the metallized layer 1 of the input / output terminal 13 are formed.
3a deviates from a predetermined position to be connected by a bonding wire, so that the optical semiconductor element 16 and the input / output terminal 1
There is a portion where the length of the bonding wire for making an electrical connection with the connection 3 becomes very long. For this reason, the impedance at that portion increases. As a result, there is a problem that the transmission efficiency of the high-frequency signal between the optical semiconductor element 16 and the input / output terminal 13 is impaired.

As a means for solving such a problem, one side (one side) of the frame 12 is attached to the optical semiconductor element 16.
Of the optical semiconductor element 16 so as to be parallel to one side of the frame 12
Although it is conceivable to mount and fix the optical fiber 19 on the upper surface of the base 11, it is difficult to install the frame body 12 exactly perpendicular to the upper surface of the base 11. It is hard to be parallel to. In addition, when there are many optical semiconductor devices having such optical fibers 19 whose optical axes are shifted, if the optical axes of the optical fibers 19 are individually adjusted on the external electric circuit board, the adjustment work becomes complicated. Become.

When the amount of heat generated during the operation of the optical semiconductor element 16 is very large, the heat transfer from the optical semiconductor element 16 to the heat sink portion of the external electric circuit board is determined by the thermal conductivity of the base 11 having the structure shown in FIG. Is not enough. That is, the mounting portion 11a on the upper surface of the base 11 has the Cu plate 111B
The optical semiconductor element 16 is mounted and fixed not only on the part having a very high thermal conductivity like the above but also on the part of the Mo plate 111A having a low thermal conductivity, so that the heat generated when the optical semiconductor element 16 operates is extremely low. When it is too large, heat is stored in the Mo plate 111A of the base 11, so that it is difficult to efficiently transfer heat to the heat sink.

Further, the frame body 12 is usually made of an Fe--Ni--Co alloy or the like in order to approximate the thermal expansion coefficient of the base body 11, which has a thermal conductivity of about 17 W / m.K and Since the temperature is very low, heat is stored in a space (internal space) formed by the base 11 and the frame 12, and it is difficult to efficiently radiate heat to the atmosphere. Further, as a material of the frame 12, Cu-tungsten (W) whose thermal expansion coefficient is close to that of the base 11 is used.
Although it is conceivable to use an alloy, this alloy has a low thermal conductivity of about 180 to 200 W / m · K, and as a result, it is difficult to efficiently radiate heat to the atmosphere.

As a result, the substrate 11 and the internal space are warped and deformed by the stress caused by heat remaining in the internal space and the space between the substrate 11 and the frame 12 and between the substrate 11 and the input / output terminals 13.
And the input / output terminal 13 may be cracked.

Further, since the Mo plate 111A has a very high rigidity, it may not be possible to stretch the Mo plate 111A uniformly during rolling. In this case, there is a portion where the thickness of the Mo plate 111A is larger than a desired thickness,
There is a portion thinner than the desired thickness on the plate 111B,
Alternatively, defects such as voids (voids) exist between the Mo plate 111A and the Cu plate 111B. for that reason,
The average thermal expansion coefficient after lamination is not as desired, and peeling may occur between the base 11 and the frame 12, between the base 11 and the input / output terminals 13, or cracks may occur on the input / output terminals 13. Cracks, or a decrease in heat conduction due to the voids.

As a result, the optical semiconductor element 16 cannot be airtightly sealed due to the cracks or peeling, and the optical semiconductor element 16 cannot be oxidized and corroded. There was a problem that malfunction occurred.

Accordingly, the present invention has been completed in view of the above problems, and an object of the present invention is to ensure the airtightness of an optical semiconductor device such as an LD and a PD, and to establish a connection between the optical semiconductor device and an optical fiber. It is an object to improve the light coupling efficiency and to improve the high-frequency transmission characteristics between the optical semiconductor element and the input / output terminal. Another object of the present invention is to operate the optical semiconductor element normally and stably for a long period of time by efficiently transmitting heat generated during operation of the optical semiconductor element to the atmosphere or a heat sink.

[0020]

An optical semiconductor package according to the present invention has a substantially rectangular parallelepiped shape, and a mounting portion for mounting an optical semiconductor element on a bottom surface of a concave portion formed on an upper surface and a concave portion from one side. A base having an optical fiber fixing member mounting portion comprising a through hole formed over the entirety thereof and an input / output terminal mounting portion comprising a through opening or a notch formed from the other side to the concave portion; and an optical fiber fixing member mounting portion. In the optical semiconductor element housing package including the fitted cylindrical optical fiber fixing member and the input / output terminal fitted to the input / output terminal mounting portion, the main body has a substantially concave shape. The molybdenum plate member and the copper plate member are arranged vertically and alternately arranged in the horizontal direction, and their main surfaces are brazed. The thickness of the molybdenum plate member is T1, the copper plate portion is The thickness T2, the thickness of the brazing material layer between the copper plate member and the molybdenum plate member when the T3, characterized in that it is a T1 / (T2 + T3) = 4~9.

According to the present invention, there is provided an airtightness of an optical semiconductor element, a light coupling efficiency between an optical semiconductor element and an optical fiber, a high-frequency transmission characteristic between an optical semiconductor element and an input / output terminal, and an optical semiconductor element. The heat conductivity of the heat generated during the operation can be improved. Further, the thickness of the molybdenum plate member is T1,
When the thickness of the copper plate member is T2 and the thickness of the brazing material layer between the molybdenum plate member and the copper plate member is T3, T1 / (T2 + T
3) By setting 4 to 9, heat conductivity of heat generated during operation of the optical semiconductor element can be further improved.

Further, an optical semiconductor device of the present invention is an optical semiconductor package of the present invention, an optical semiconductor element mounted and fixed on a mounting portion and electrically connected to input / output terminals, and joined to an upper surface of a base. And a lid body.

The present invention can provide a highly reliable optical semiconductor device using the above-mentioned semiconductor package.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The optical semiconductor package of the present invention will be described in detail below. FIG. 1 is a perspective view of an optical semiconductor package of the present invention, and FIG. 2 is a partially enlarged cross-sectional view of a base in the semiconductor package of the present invention. In these figures, reference numeral 1 denotes a mounting portion for mounting the optical semiconductor element on the bottom surface of the concave portion formed on the upper surface, an optical fiber fixing member attaching portion formed from one side to the concave portion, and another side portion. And a base having an input / output terminal mounting portion formed from the groove to the recess. Reference numeral 2 denotes an input / output terminal fitted to the input / output terminal mounting portion, 4 denotes a fixing member mounted to the optical fiber fixing member mounting portion, and 5 denotes an optical semiconductor element such as an LD or PD. The base 1, the input / output terminals 2, and the fixing member 4 mainly constitute a container for housing the optical semiconductor element 5 therein.

The optical semiconductor device 5 is mounted on the container, the optical semiconductor device 5 mounted and fixed on the mounting portion 1a of the substrate 1, and the lid 6 bonded to the uppermost surface of the substrate 1 and sealing the optical semiconductor device 5. The device is configured.

The substrate 1 of the present invention functions as a support plate for supporting the optical semiconductor element 5 and a heat radiating plate for transmitting heat generated during operation of the optical semiconductor element 5 to a heat sink portion or the outside (in the atmosphere). In addition, a mounting portion 1a on which the optical semiconductor element 5 is mounted is provided substantially at the center of the bottom surface of the concave portion formed on the upper surface of the base 1. The optical semiconductor element 5 is mounted and fixed on the mounting portion 1a via an adhesive such as tin (Sn) -lead (Pb) solder, resin, or glass.
The heat generated at the time of the operation is transmitted to the base 1 via the adhesive, and the operability of the optical semiconductor element 5 is improved.

The base 1 has an optical fiber fixing member mounting portion 1b formed of a through hole formed from one side portion to a concave portion, and a through hole or cutout portion formed from the other side portion to a concave portion. It has an output terminal mounting portion 1c.

The substrate 1 of the present invention is made of Mo having a very high rigidity.
The plate member 1A and the Cu plate member 1B having a very high thermal conductivity are formed by combining Ag-Cu brazing or the like mainly composed of silver (Ag) having a very high thermal conductivity and Cu having a very high thermal conductivity. They are brazed and joined via the brazing material layer 1C, and their thickness ratios are set such that the thermal expansion coefficient of the base 1 approximates the thermal expansion coefficients of the input / output terminals 2 and the fixing member 4. .

That is, the thickness of the Mo plate member 1A is T1, Cu
When the thickness of the plate member 1B is T2 and the thickness of the brazing material layer 1C is T3, the ratio of the thickness is T1 / (T2 + T3) =
4 to 9. When T1 / (T2 + T3) is less than 4,
Since the coefficient of thermal expansion of the base 1 is much larger than the coefficient of thermal expansion of the input / output terminals 2 and the fixing member 4, the bonding strength between the base 1 and the input / output terminals 2 and the fixing member 4 after brazing is reduced. It will be easier. Further, since the brazing material layer 1C cannot effectively reduce the thermal strain due to the difference in thermal expansion between the Mo plate member 1A and the Cu plate member 1B, a large warp deformation is generated in the base 1, and the optical semiconductor element 5 is firmly mounted. It becomes difficult to fix. Also,
Due to the warpage of the base 1, it is difficult to join the lid 6 for sealing the optical semiconductor element 5 to the upper surface of the base 1. Therefore, when the optical semiconductor device is formed, the airtightness of the optical semiconductor element 5 cannot be improved, and the optical semiconductor element 5 is oxidized and corroded.

On the other hand, when T1 / (T2 + T3) exceeds 9, the thermal expansion coefficient of the base 1
It is difficult to approximate to that of
Has a reduced thermal conductivity. For this reason, it is difficult to efficiently transmit the heat generated by the optical semiconductor element 5 during operation to the heat sink portion and the atmosphere.
The bonding strength after the brazing with the fixing member 4 is reduced, or a large warp deformation is generated in the base 1, so that the optical semiconductor element 5 cannot be firmly mounted and fixed. In addition, the warpage of the base 1 makes it difficult to join the lid 6 to the uppermost surface of the base 1. Therefore, when the optical semiconductor device is formed, the airtightness of the optical semiconductor element 5 cannot be improved, and the optical semiconductor element 5 is liable to be oxidized and corroded.

Specifically, the thickness T1 of the Mo plate member 1A is preferably 0.8 to 7.2 mm. If less than 0.8mm,
Since the thickness is too thin, the shape retention of the substrate 1 is easily impaired. If the thickness exceeds 7.2 mm, the area of a portion having relatively low thermal conductivity becomes large, so that it becomes difficult to efficiently transfer heat generated when the semiconductor element 5 operates.

The thickness T2 of the Cu plate member 1B is 0.2
~ 0.8 mm is preferred. If the thickness is less than 0.2 mm, it becomes difficult to efficiently transfer heat generated when the semiconductor element 5 operates. Further, when the brazing material layer 1C is melted, it becomes easy to form a eutectic between the brazing material layer 1C and the Cu plate member 1B, and when the eutectic is formed, voids are generated in the brazing material layer 1C,
Thermal conductivity deteriorates. If it exceeds 0.8 mm, the area of the portion having a large thermal expansion coefficient becomes large, so that peeling occurs due to a difference in thermal expansion generated between the base 1 and the input / output terminal 3 or the mounting portion 1a of the semiconductor element 5 The bondability with respect to becomes easy to fall.

The brazing material layer 1C has a desired average thermal expansion coefficient of the base 1 even when there is a portion where the thickness of the Mo plate member 1A or the Cu plate member 1B is different from the set thickness. Heat can be efficiently transmitted to the heat sink portion and the atmosphere during the operation of the optical semiconductor element 5, and further, the stress at which the heat during the operation of the optical semiconductor element 5 tends to cause the substrate 1 to warp can be reduced. I do.

That is, the brazing material layer 1C is made of Cu and Cu, which are very soft and the same material as the Cu plate member 1B.
Since the plate member 1B is mainly composed of Ag whose thermal conductivity and coefficient of thermal expansion are close to each other, even if there is a portion different from the thickness set for the Mo plate member 1A or the Cu plate member 1B, In the portion, the brazing material layer 1C has a function of replacing the function of heat transfer and thermal expansion matching of the Cu plate member 1B and a function of effectively preventing the base 1 from warping.

The thickness T3 of the brazing material layer 1C is 5-40.
μm is preferred. When the thickness is less than 5 μm, when the Mo plate member 1A and the Cu plate member 1B are joined via the brazing material layer 1C, a number of voids are formed inside the brazing material layer 1C, and the thermal conductivity of the base 1 is reduced. In addition, the function of relieving thermal stress is impaired. If it exceeds 40 μm, the softness of the base 1 itself increases, and the base 1 is easily deformed. In this case, heat transfer from the base 1 to the heat sink portion is impaired, and it becomes difficult to fit the input / output terminal 2 to the mounting portion 2a. More preferably, the thickness T3 of the brazing material layer 1C is preferably 20 to 40 μm.

The brazing material layer 1C is preferably flush with the upper and lower surfaces of the substrate 1. Brazing material layer 1C
When the optical semiconductor element 5 projects above the bottom surface of the concave portion of the base 1 (on the mounting portion 1a side), it is difficult to flatten and fix the optical semiconductor element 5 to the mounting portion 1a with good adhesion. Further, the brazing material layer 1C is the uppermost surface of the base 1 (the surface to which the lid 6 is bonded).
If it protrudes upward, it becomes difficult to bond the lid 6 to the base 1 with good adhesion and flatness. On the other hand, if the brazing material layer 1C protrudes below the lower surface of the base 1 (toward the heat sink), it becomes difficult to join the base 1 to the heat sink with good adhesion and flatness. That is, in these cases, the airtightness of the optical semiconductor element 5 is impaired, and it is difficult to efficiently transfer heat during operation of the optical semiconductor element 5 to the base 1 and the heat sink.

On the other hand, the brazing material layer 1C is located below the bottom surface of the concave portion of the base 1 (inside the base 1) or the brazing material layer 1C
Is protruding above the lower surface of the base 1 (inside of the base 1), it is difficult to efficiently transfer the heat of the semiconductor element 5 to the heat sink.

Therefore, when the brazing material layer 1C protrudes from the upper surface or the lower surface of the base 1, the protruding height is preferably about -2 μm to 2 μm for the above reason.

The Mo plate member 1A and the Cu plate member 1B of the present invention
May have a triangular or trapezoidal cross section in addition to a square cross section as shown in FIG. 2 (a cross section perpendicular to the longitudinal direction). If the cross-sectional shape is triangular, M
The o-plate members 1A and the Cu plate members 1B may be alternately arranged so that one of the triangles has the bottom side of the triangle facing down and the other has the bottom side of the triangle facing up, and the substantially rectangular parallelepiped base 1 can be configured.
When the cross-sectional shape is a trapezoid, one of the Mo plate member 1A and the Cu plate member 1B may have a trapezoidal lower base facing down, and the other may have a trapezoidal lower base facing up. 1 can be configured. Further, the Mo plate member 1A and the Cu plate member 1
One cross-sectional shape of B may be triangular, and the other cross-sectional shape may be trapezoidal.

When the cross-sectional shapes of the Mo plate member 1A and the Cu plate member 1B are triangular or trapezoidal, the Mo plate member 1A of the Mo plate member 1A and the Cu plate member 1B has It is preferable to arrange so as to be larger than the surface serving as the lower surface. That is, if the surface of the Mo plate member 1A serving as the upper surface of the base 1 is small, the bonding strength between the base 1 and the frame 2 and the input / output terminals 3 after brazing is reduced, or the base 1 is greatly warped. This makes it difficult to firmly mount and fix the semiconductor element 5. Further, since the coefficient of thermal expansion of the semiconductor element 5 is largely different from the coefficient of thermal expansion of the Cu plate member 1B, the bonding property of the semiconductor element 5 to the mounting portion 1a is easily deteriorated.

The cross-sectional shapes of the Mo plate member 1A and the Cu plate member 1B are preferably rectangular as shown in FIG. 4, so that the base 1 can be easily formed, uneven distribution of stress can be suppressed, and heat It is easy to make the conduction characteristics uniform throughout the substrate 1.

In the present invention, the frame-shaped portion surrounding the mounting portion 1a is also made of exactly the same material as the substrate 1 having the mounting portion 1a. Even if it is transmitted from the peripheral portion of the portion 1a to the frame-shaped portion, it is efficiently radiated from the frame-shaped portion to the atmosphere. That is, the optical semiconductor element 5
Even if the amount of heat generated during operation is very large,
Efficient heat is generated by two paths: a path transmitted from the portion having the mounting portion 1a to the heat sink portion, and a path transmitted from the portion having the mounting portion 1a to the atmosphere through the frame surrounding the mounting portion 1a. May dissipate.

Specifically, the heat generated when the optical semiconductor element 5 operates is transmitted from the mounting portion 1a to the heat sink portion,
A heat conduction path vertically transmitted by the o-plate member 1A, the Cu-plate member 1B, and the brazing material layer 1C, and a substantially horizontal direction to the heat sink portion through the Mo-plate member 1A, the Cu-plate member 1B, and the brazing material layer 1C in order. In the first path with the heat conduction path that is gently transmitted. In addition, the second portion that is radiated to the atmosphere through the Mo plate member 1A, the Cu plate member 1B, and the brazing material layer 1C sequentially from the mounting portion 1a or the internal space to the frame portion surrounding the mounting portion 1a. Heat is transferred in the path. Therefore, it is possible to efficiently dissipate the light by the two paths of the first path and the second path.

The portion having the mounting portion 1a and the mounting portion 1
a and the frame-shaped portion surrounding a
As in the related art, there is no concern that a gap is formed between them and the airtightness of the optical semiconductor element 5 is impaired. Also,
The mounting section 1 such that the light input / output end face of the optical semiconductor element 5 is parallel to one side (one side face) of the frame-shaped section surrounding the mounting section 1a.
a, the optical axis of the optical semiconductor element 5 and the optical fiber 8 fixed to the fixing member 4 so as to extend almost perpendicularly to one side (one side surface) of the frame-shaped portion are extremely adjusted. It will be easier. That is, since the light input / output end face of the optical semiconductor element 5 and one side of the frame-shaped part are always parallel, the light coupling efficiency between the optical semiconductor element 5 and the optical fiber 8 can always be improved.

Further, in the present invention, since the portion having the mounting portion 1a and the frame portion are integrally formed, the electrode of the optical semiconductor element 5 is always in contact with the metallized layer 2a of the input / output terminal 2. Since it is at a predetermined position to be connected, there is no need to generate a portion where the length of the bonding wire for electrically connecting them must be extremely long. Therefore, since the length of the bonding wire can be always constant at any part, the optical semiconductor element 5 has an impedance that is always constant. Therefore, the transmission characteristics of the high-frequency signal between the optical semiconductor element 5 and the input / output terminal 2 are always good.

As described above, the base 1 of the present invention is
A Mo plate member 1A, which has a structure in which a portion having a shape and a frame-shaped portion are integrally formed, has extremely high rigidity and can improve the shape retention of the base 1, and an optical semiconductor having a very high thermal conductivity. The Cu plate member 1B, which can transmit heat generated during the operation of the element 5 satisfactorily, is joined between the Mo plate member 1A and the Cu plate member 1B to reduce thermal stress due to a difference in thermal expansion between the Cu plate member 1A and the Cu plate member 1B. This is a configuration in which a brazing material layer 1C having a heat transfer function like the plate member 1B is alternately vertically stacked in a plurality of layers. When the thickness of the Mo plate member 1A is T1, the thickness of the Cu plate member 1B is T2, and the thickness of the brazing material layer 1C is T3, the ratio of the thickness is T1 / (T2 + T3) = 4 to
9, and the thickness of the brazing material layer 1C is preferably 5 to 40 μm.
m or more.

With this configuration, the airtightness of the optical semiconductor device 5, the coupling efficiency of light between the optical semiconductor device 5 and the optical fiber 8,
The high-frequency transmission characteristics between the optical semiconductor element 5 and the input / output terminal 2 and the heat transfer of heat generated when the optical semiconductor element 5 operates can be improved.

A metal having excellent corrosion resistance and excellent wettability with an adhesive on the surface of the substrate 1, specifically, a metal having a thickness of 0.5 to
It is preferable that a 9 μm Ni layer and a 0.5 to 9 μm thick gold (Au) layer are sequentially deposited by a plating method, so that oxidation and corrosion of the substrate 1 can be effectively prevented, and the upper surface of the substrate 1 can be effectively prevented. The optical semiconductor element 5 can be firmly placed and fixed on the bottom surface of the concave portion. Further, the lid 6 can be satisfactorily bonded to the uppermost surface of the base 1 via a low melting point brazing material such as an Au-Sn alloy.

On one side of the frame-shaped portion of such a base 1,
An optical fiber fixing member mounting portion 1b formed of a through hole and serving as an optical signal path is formed, and an input / output terminal 2 having a function of inputting / outputting a high-frequency signal to / from an external electric circuit board is fitted on the other side. An input / output terminal mounting portion 1c formed of a through opening or a notch for attachment is formed.

A fixing member for fixing the supporting member 7 through which the optical fiber 8 is inserted and adhered with a resin adhesive or the like is provided on the inner peripheral surface of the optical fiber fixing member attaching portion 1b or the peripheral portion of the opening on the outer surface side of the base 1. The member 4 is joined with a brazing material such as Ag brazing. This fixing member 4 is made of an Fe—Ni—Co alloy or an Fe—Ni—Co alloy.
Made of a metal material such as a Ni alloy, for example, Fe-Ni-C
In the case of an o-alloy, an ingot of this alloy is formed into a predetermined shape by subjecting the ingot to metal working such as rolling or pressing. Further, in order to effectively prevent oxidative corrosion, a 0.5-9 μm Ni layer or a 0.5-5 μm
It is preferable to apply a metal layer such as an Au layer by a plating method.

A translucent member 9 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 surface of the fixing member 4 on the surface of the joint. 200- through the metallized layer
It is joined with a low melting point brazing material such as an Au-Sn alloy having a melting point of 400 ° C. This translucent member 9 has a coefficient of thermal expansion of 4
１２12 ppm / ° C. (× 10 ^-6 / ° C.) (room temperature to 400 ° C.)
Made of sapphire (single crystal alumina), amorphous glass, or the like, and has a spherical, hemispherical, convex lens shape, rod lens shape, or the like. Then, a light such as an external laser beam transmitted through the optical fiber 8 is input to the optical semiconductor element 5, or a condensing light for inputting the laser light or the like output from the optical semiconductor element 5 to the optical fiber 8. Used as a member. When the translucent member 9 is 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 material containing boric acid or silica sand as a main component It is preferable to use an acid type.

Even if the translucent member 9 has a different coefficient of thermal expansion from that of the base 1, the fixing member 4 absorbs and relaxes the stress due to the difference in thermal expansion, so that the crystal axis is due to the stress. It is unlikely that a change in the refractive index of light due to the alignment in the direction will occur. Therefore, by using such a translucent member 9, the coupling efficiency of light between the optical semiconductor element 5 and the optical fiber 8 can be increased.

The supporting member 7 is provided with a YAG
Since it is joined by laser welding or the like, it is better to be made of a metal material like the fixing member 4. Further, the thermal expansion coefficient of the support member 7 is preferably made of the same material as that of the fixing member 4 so that the optical axis of the optical semiconductor element 5 and the optical fiber 8 do not shift. Therefore, the material of the support member 7 is preferably an Fe—Ni—Co alloy if the fixing member 4 is an Fe—Ni—Co alloy, and is a Fe—Ni alloy if the fixing member 4 is an Fe—Ni alloy.
It is good to be an alloy.

The input / output terminal 2 is fitted to the input / output terminal mounting portion 1c on the inner peripheral surface thereof through a brazing material such as Ag brazing. The input / output terminal 2 functions as an input / output unit for a high-frequency signal between the inside and the outside of the optical semiconductor package, and has a function of closing the inside of the optical semiconductor package. The input / output terminal 2 is composed of an insulator such as alumina (Al ₂ O ₃ ) ceramics or aluminum nitride (AlN) ceramics, and a metallized layer 2 a as a metal conductor formed so as to extend inside and outside the optical semiconductor package. Be composed. Also, the metallized layer 2a inside the optical semiconductor package
Is electrically connected to the electrode of the optical semiconductor element 5 via a bonding wire.

The input / output terminal 2 is manufactured as follows. An appropriate organic binder, a solvent and the like are added to and mixed with the raw material powder to be an insulator to form a paste, and the paste is used to form a ceramic green sheet by a doctor blade method or a calender roll method. This ceramic green sheet is provided with W, M serving as a metallized layer 2a.
A metal paste obtained by adding an organic solvent and a solvent to a powder of o, manganese (Mn) or the like is preliminarily printed and coated in a desired shape by a conventionally known screen printing method, and is heated to about 1600 ° C.
It is produced by sintering at a high temperature.

The insulator of the input / output terminal 2 has a function of electrically insulating the portion of the base 1 having the mounting portion 1a from the frame-like portion surrounding the mounting portion 1a. It is appropriately selected according to characteristics such as a dielectric constant and a coefficient of thermal expansion.

A lead terminal 3 is bonded to the upper surface of the metallized layer 2a outside the optical semiconductor package via a brazing material such as Ag brazing. This lead terminal 3 is an input / output terminal 2
In order to make the bond with the I / O terminal firm, a member having an approximate thermal expansion coefficient of the input / output terminal 2 is used. For example, when the insulator of the input / output terminal 2 is made of Al ₂ O ₃ ceramics, the lead terminal 3 is made of an Fe—Ni—Co alloy or an Fe—Ni alloy.

As described above, the optical semiconductor package of the present invention has a substantially rectangular parallelepiped shape, and the mounting portion 1a for mounting the optical semiconductor element 5 on the bottom surface of the concave portion formed on the upper surface and the concave portion from one side. A base member 1 having an optical fiber fixing member mounting portion 1b formed of a through hole formed over the base and an input / output terminal mounting portion 1c formed of a through opening or cutout formed from the other side to the concave portion; The base body 1 includes a cylindrical fixing member 4 fitted to the mounting portion 1b and an input / output terminal 2 fitted to the input / output terminal mounting portion 1c. Mo plate member 1A shaped to be divided by a number of surfaces substantially parallel to the side surface
And the Cu plate member 1B are vertically arranged alternately in the horizontal direction, and their main surfaces are brazed. The thickness of the Mo plate member 1A is T1, the thickness of the Cu plate member 1B is Where T2 is the thickness of the brazing material layer 1C between the Mo plate member 1A and the Cu plate member 1B, and T1 / (T2 + T3)
= 4-9.

The Mo plate member 1A and the Cu plate member 1
Each main surface of B has a shape obtained by cutting the base 1 at a number of surfaces substantially parallel to one side surface thereof, and has a substantially concave shape as is clear from FIGS. The base 1 is formed by joining these main surfaces. Further, in order to form an overhang at the lower end of the side surface of the base 1, a horizontally long rectangular (strip-shaped) member may be joined to the lower part of the end surface of the base 1. Furthermore, in a substantially concave shape,
It is preferable to form a projecting portion projecting laterally (in the plane direction) at the lower end of both sides, so that the area of the lower surface of the base 1 is increased and the stability is improved. Stability is improved.

The optical semiconductor package of the present invention, an optical semiconductor element 5 mounted and fixed on the mounting portion 1a and electrically connected to the input / output terminal 2, and a lid bonded to the uppermost surface of the base 1 The provision of the body 6 results in an optical semiconductor device as a product. The optical fiber 8 whose end is inserted into the fixing member 4 is generally provided when the optical semiconductor device is used. However, the optical fiber 8 may be added to the optical semiconductor device as a single item, or the optical semiconductor device may be connected to an external electric device. It may be attached when it is used by being fixed to a circuit board or the like.

More specifically, the optical semiconductor element 5 is bonded and fixed to the upper surface of the mounting portion 1a with an adhesive such as glass, resin, brazing material and the like, and the electrodes of the optical semiconductor element 5 are bonded with bonding wires. The lid 6 is electrically connected to a predetermined metallized layer 2a.
An optical semiconductor as a product in which the optical semiconductor element 5 is housed inside an optical semiconductor package including the base 1, the input / output terminals 2, the fixing member 4, and the translucent member 9 by joining with a low melting point brazing material such as n. Device.

In such an optical semiconductor device, for example, the optical semiconductor element 5 is optically excited by a high-frequency signal supplied from an external electric circuit board, and the excited light such as laser light is transmitted to and received from the optical fiber 8 through the light transmitting member 9. By transmitting the data through the optical fiber 8, it functions as a photoelectric conversion device capable of transmitting a large amount of information at high speed, and is frequently used in the field of optical communication and the like.

It should be noted that the present invention is not limited to the above embodiment, and that various changes may be made without departing from the scope of the present invention. For example, the optical semiconductor device may be provided with an optical isolator for preventing return light inside or outside, for example, inside or outside the base 1 of the fixing member 4 or in the middle of the optical fiber 8 outside the base 1.
In this case, the light coupling efficiency between the optical semiconductor element 5 and the optical fiber 8 is further improved. Further, the outermost layer (outermost layer) and the innermost layer (layer closest to the inner space) of the frame-shaped portion of the base 1 are preferably made of the Cu plate member 1B, and the heat dissipation to the outside and the heat sink portion is improved. .

[0064]

The present invention has a substantially rectangular parallelepiped shape and comprises a mounting portion for mounting an optical semiconductor element on the bottom surface of a concave portion formed on the upper surface and a through hole formed from one side to the concave portion. A base having an optical fiber fixing member mounting portion and an input / output terminal mounting portion formed of a through opening or a cutout formed from the other side portion to the concave portion is formed of a Mo plate member having a substantially concave main surface shape and Cu. The plate members are arranged vertically and alternately arranged in the horizontal direction, and their main surfaces are brazed. The thickness of the Mo plate member is T1, the thickness of the Cu plate member is T2, and the Mo plate member is T2. When the thickness of the brazing material layer between the member and the Cu plate member is T3, T1 / (T2 + T3) =
Since it is 4 to 9, the airtightness of the optical semiconductor element, the coupling efficiency of light between the optical semiconductor element and the optical fiber, the high-frequency transmission characteristics between the optical semiconductor element and the input / output terminal, and the heat generated during operation of the optical semiconductor element It has the effect that the heat transfer can be made very good. As a result, the optical semiconductor element can be normally and stably operated for a long time.

Further, the optical semiconductor device of the present invention comprises an optical semiconductor package of the present invention, an optical semiconductor element mounted and fixed on a mounting portion and electrically connected to input / output terminals, and joined to the uppermost surface of the base. With such a lid, a highly reliable optical semiconductor device using the optical semiconductor package having the above-described functions and effects can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an embodiment of an optical semiconductor package of the present invention.

FIG. 2 is a partially enlarged sectional view of a base in the optical semiconductor package of FIG. 1;

FIG. 3 is a perspective view of a conventional semiconductor package.

FIG. 4 is a partially enlarged sectional view of a base in the semiconductor package of FIG. 3;

FIG. 5 is a perspective view when the semiconductor package of FIG. 3 is an optical semiconductor package.

[Explanation of symbols]

 1: Base 1a: Mounting section 1b: Optical fiber fixing member mounting section 1c: Input / output terminal mounting section 1A: Molybdenum plate 1B: Copper plate 1C: Brazing material layer 2: Input / output terminal 4: Optical fiber fixing member 5: Optical semiconductor Element 6: Lid

Claims (2)

[Claims] 1. An optical fiber fixing device having a substantially rectangular parallelepiped shape and comprising a mounting portion for mounting an optical semiconductor element on a bottom surface of a concave portion formed on an upper surface and a through hole formed from one side to the concave portion. A base having an input / output terminal mounting portion comprising a member mounting portion and a through-opening or notch formed from the other side portion to the concave portion, and a cylindrical optical fiber fitted to the optical fiber fixing member mounting portion A fixing member,
In the optical semiconductor device housing package having an input / output terminal fitted to the input / output terminal mounting portion, the base is formed by vertically placing a molybdenum plate member and a copper plate member having a substantially concave main surface shape. The molybdenum plate member has a thickness of T1 and the copper plate member has a thickness of T1.
2. When the thickness of the brazing material layer between the molybdenum plate member and the copper plate member is T3, T1 / (T2 + T3) = 4
A package for storing an optical semiconductor element. 2. An optical semiconductor element storage package according to claim 1, wherein the optical semiconductor element is mounted on and fixed to the mounting portion and electrically connected to the input / output terminal, and is bonded to an upper surface of the base. An optical semiconductor device, comprising: a lid;