JP2000106407A - Optical semiconductor element housing package - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical semiconductor element housing package having high transmission efficiency of optical signal by a method wherein the light stimulated by the optical semiconductor element is transferred efficiently to optical fiber through a light transmitting member. SOLUTION: This is an optical semiconductor element housing package consisting of a substrate 1 having a mounting part where an optical semiconductor element 4 is mounted on the upper surface, a frame body 2 attached to the substrate 1 surrounding the optical semiconductor element mounting part 1a and having a through hole 2a on the side part, a cylindrical fixing member 9 attached to the through hole 2a of the frame body 2 and having the space where an optical signal is transmitted to the internal part, a light transmitting member 10 attached to the edge face of the cylindrical fixing member 9, and a cover member 3 attached to the upper surface of the frame body 2 and airtightly sealing the optical semiconductor element 4. Said fixing member 9 has a recessed part on the edge face, the light transmitting member 10 is attached to the bottom face of the recessed part, and a space of 1 mm or more is provided between the inner side face of the recessed part and the outer circumference of the light transmitting member 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical semiconductor element housing package for housing an optical semiconductor element.

[0002]

2. Description of the Related Art Conventionally, an optical semiconductor device housing package for housing an optical semiconductor device is generally made of a metal such as an iron-nickel-cobalt alloy or a copper-tungsten alloy. A metal base having a mounting portion to be mounted, a plurality of external lead terminals fixed around the mounting portion so as to penetrate from an upper surface to a lower surface via an insulating member, and a metal substrate surrounding the optical semiconductor element mounting portion. And a frame made of an iron-nickel-cobalt alloy or the like having a through hole on the side and joined to the metal base via a brazing material such as silver brazing, and gold-tin in the through hole of the frame. A cylindrical fixing member made of a metal such as an iron-nickel-cobalt alloy having a space in which an optical signal is transmitted, which is attached via a brazing material such as an alloy, and an end surface of the cylindrical fixing member. The melting point is 300 in the provided recess. A light-transmitting member made of amorphous glass or the like that blocks the inside of the fixed member attached via a low-melting-point brazing material such as a gold-tin alloy at 400 ° C .; And a lid member for hermetically sealing the semiconductor element. The optical semiconductor element is bonded and fixed to the optical semiconductor element mounting portion of the metal base, and each electrode of the optical semiconductor element is connected to an external lead via a bonding wire. The optical semiconductor element is electrically connected to a terminal, and thereafter, a lid member is joined to the upper surface of the frame body, and the optical semiconductor element is hermetically housed in a container including the metal base, the frame body, and the lid member, and the cylindrical fixing member By connecting an optical fiber to the optical semiconductor device, an optical semiconductor device as a product is obtained.

Such an optical semiconductor device optically excites an optical semiconductor element by a drive signal supplied from an external electric circuit,
By transmitting and receiving the excited light to and from the optical fiber through the light transmitting member, the device functions as an optical semiconductor device used for high-speed optical communication or the like by transmitting the light inside the optical fiber.

[0004]

However, in this conventional package for housing an optical semiconductor device, the thermal expansion coefficient of the amorphous glass constituting the translucent member is about 8.5 ×.
10 ⁻⁶ / ° C. (30 ° C. to 400 ° C.), whereas the thermal expansion coefficient of the iron-nickel-cobalt alloy constituting the cylindrical fixing member is about 4.5 × 10 ⁻⁶ / ° C. (Rt) Up to 400 ° C)
Since the translucent member is attached to the cylindrical fixing member while being fitted in the concave portion provided at the end of the cylindrical fixing member, the translucent member is attached to the cylindrical fixing member with a low melting point brazing. When attaching through a material, thermal stress is generated between the translucent member and the fixing member due to a difference in thermal expansion coefficient between the translucent member and the fixing member, and this acts from the outer peripheral portion of the translucent member to transmit light. When the light excited by the optical semiconductor element is transmitted to and received from the optical fiber through the light transmitting member, the light excited by the optical semiconductor element passes through the light transmitting member. The intrinsic stress causes birefringence, and only a part of the light is transmitted to and received from the optical fiber, so that the efficiency of transmitting and receiving the light to and from the optical fiber deteriorates, and the transmission efficiency of the optical signal deteriorates. I was

In order to solve the above-mentioned drawbacks, the fixing member to which the light-transmitting member made of amorphous glass is attached is made of a metal material having a thermal expansion coefficient close to that of the light-transmitting member. It is possible.

When the coefficient of thermal expansion of the fixing member is approximated to the coefficient of thermal expansion of the translucent member, when the translucent member is attached to the fixing member, the heat between the two members is fixed between the translucent member and the fixing member. Thermal stress due to the difference in expansion coefficient is hardly generated, and stress is hardly present in the light transmitting member.

However, although this fixing member does not generate stress between the fixing member and the light transmitting member when the light transmitting member is attached, it does not include a metal material such as an iron-nickel-cobalt alloy. The frame has a different thermal expansion coefficient from that of the frame, and when the fixing member in which the translucent member is attached to the through hole of the frame is attached via a brazing material such as a gold-tin alloy, A thermal stress is generated between the body and the fixing member due to the difference in the coefficient of thermal expansion between the body and the fixing member, and this acts from the outer peripheral portion of the light transmitting member attached to the fixing member to cause the inside of the light transmitting member to move. As a result, when the light excited by the optical semiconductor element is transmitted and received to the optical fiber through the translucent member, the optical semiconductor element passing through the translucent member causes birefringence in the excited light, The efficiency of transmitting and receiving light to and from optical fibers is Would induce the disadvantage that the transmission efficiency of the deteriorates.

The present invention has been devised in view of the above-mentioned drawbacks, and has as its object to efficiently transmit and receive light excited by an optical semiconductor element to and from an optical fiber via a light-transmitting member, thereby improving the transmission efficiency of an optical signal. An object of the present invention is to provide a package for storing an optical semiconductor element.

[0009]

According to the present invention, there is provided a base having a mounting portion on which an optical semiconductor element is mounted on an upper surface, and mounted on the base so as to surround the optical semiconductor device mounting portion, A frame having a through hole in a side portion, a cylindrical fixing member attached to the through hole of the frame, and having a space for transmitting an optical signal therein; and a frame fixed to an end surface of the cylindrical fixing member. An optical semiconductor element housing package comprising: a light-transmitting member attached to the fixing member; and a lid member attached to an upper surface of the frame body and hermetically sealing the optical semiconductor element. The fixing member has a concave portion on the end surface, a light-transmitting member is attached to the bottom surface of the concave portion, and a gap of 1 mm or more is formed between the inner surface of the concave portion and the outer periphery of the light-transmitting member. It is a feature.

According to the package for housing an optical semiconductor element of the present invention, a gap of 1 mm or more is provided between the inner surface of the recess and the outer periphery of the light-transmitting member on the bottom surface of the recess provided with the light-transmitting member on the end surface of the fixing member. Since there is a difference in the coefficient of thermal expansion between the translucent member and the fixing member, or between the frame body and the fixing member, when the translucent member is attached to the fixing member, ,
Alternatively, when the fixing member to which the light-transmitting member is attached is attached to the through hole of the frame, the difference in thermal expansion coefficient between the light-transmitting member and the fixing member or between the frame and the fixing member may be reduced. A thermal stress is generated, and even if the thermal stress acts on the translucent member from the outer peripheral portion, 1 m is formed between the inner surface of the concave portion and the outer periphery of the translucent member.
Since there is an interval of m or more, the stress does not act on the translucent member, and as a result, there is no thermal stress inherent in the translucent member. Therefore, when the light excited by the optical semiconductor element is transmitted to the optical fiber through the translucent member, the light excited by the optical semiconductor element does not cause birefringence due to the thermal stress inherent in the translucent member. The transmission and reception are performed between the members, and the transmission efficiency of the optical signal becomes extremely high.

[0011]

Next, the present invention will be described in detail with reference to the accompanying drawings. 1 and 2 show an embodiment of the package for housing an optical semiconductor element of the present invention, wherein 1 is a base, 2 is a frame, and 3 is a lid member. The base 1, the frame 2, and the cover 3
A container for accommodating the optical semiconductor element 4 is formed therein.

The base 1 acts as a support member for supporting the optical semiconductor element 4, and has a mounting section 1a for mounting the optical semiconductor element 4 at a substantially central portion of the upper surface thereof. The optical semiconductor element 4 is bonded and fixed to the portion 1a with an adhesive such as a gold-silicon brazing material with the Peltier element 5 and the like interposed therebetween.

The base 1 is made of a metal material such as an iron-nickel-cobalt alloy or a copper-tungsten alloy. For example, when the base 1 is made of an iron-nickel-cobalt alloy, it is rolled into an iron-nickel-cobalt alloy ingot. It is manufactured by applying a conventionally known metal working method such as a working method or a punching working method.

The substrate 1 has a metal having excellent corrosion resistance on its outer surface and good wettability to a brazing material, specifically a nickel layer having a thickness of 2 to 6 μm and a thickness of 0.5 to 5 μm. When the gold layers are sequentially applied by a plating method,
Can be effectively prevented from being oxidized and corroded, and the Peltier element 5 and the like disposed below the optical semiconductor element 4 can be firmly adhered and fixed on the upper surface of the base 1. Therefore, the base 1 effectively prevents oxidative corrosion and has a thickness of 2 to 6 μm on its outer surface when the Peltier element 5 or the like disposed below the optical semiconductor element 4 is firmly adhered and fixed on the upper surface.
It is preferable that a nickel layer having a thickness of m and a gold layer having a thickness of 0.5 to 5 μm are sequentially applied by plating.

The base 1 has a plurality of external lead terminals 6 penetrating the base 1 fixed around a mounting portion 1a on which the optical semiconductor element 4 is mounted via an insulating member 7 such as glass. I have.

The external lead terminal 6 functions to electrically connect each electrode of the optical semiconductor element 4 to an external gas circuit. One end of the external lead terminal 6 is connected to an electrode of the optical semiconductor element 4 via a bonding wire 8. The other end is connected to an external electric circuit via a brazing material such as solder.

The external lead terminal 6 is made of, for example, a metal material such as an iron-nickel-cobalt alloy or an iron-nickel alloy.
A hole having a slightly larger diameter is formed, and the insulating member 7 made of a ring-shaped glass and the external lead terminal 6 are inserted into the hole, and then the insulating member 7 made of the glass is heated and melted. .

The external lead terminal 6 is provided with a plating metal layer having excellent corrosion resistance such as a nickel plating layer and a gold plating layer on its surface and having good wettability with a brazing material in a thickness of 1.0 μm to 2 μm.
When the external lead terminal 6 is adhered to a thickness of 0 μm, oxidation corrosion of the external lead terminal 6 is effectively prevented, and the connection between the external lead terminal 6 and the bonding wire 8 can be made strong. Therefore, the external lead terminal 6 is provided with a plating metal layer having excellent corrosion resistance such as a nickel plating layer and a gold plating layer on its surface and having good wettability with the brazing material from 1.0 μm to 2 μm.
Preferably, it is applied to a thickness of 0 μm.

On the upper surface of the base 1, a frame 2 is mounted so as to surround the mounting portion 1a on which the optical semiconductor element 4 is mounted.
Are formed, and a space for accommodating the optical semiconductor element 4 is formed inside the frame 2.

The frame 2 is made of a metal material such as an iron-nickel-cobalt alloy or an iron-nickel alloy. For example, the frame 2 is formed by pressing an ingot (mass) of an iron-nickel-cobalt alloy or the like into a frame shape by pressing. And the substrate 1
Attachment is performed by brazing the upper surface of the base 1 and the lower surface of the frame 2 via a silver brazing material.

The frame 2 is provided with a through hole 2a on a side portion thereof, and a cylindrical fixing member 9 is attached to the through hole 2a, and a concave portion 9a is formed on an inner end surface of the fixing member 9. The light transmitting member 10 is attached to the bottom of the concave portion.

A through hole 2a formed on the side of the frame 2 acts as a mounting hole for mounting the fixing member 9, and a conventionally well-known drill hole is formed on the side of the frame 2. By applying, it is formed in a predetermined shape.

A cylindrical fixing member 9 is further attached to the through hole 2a of the frame 2, and the fixing member 9 functions as a base fixing member when fixing the optical fiber member 11 to the frame 2. At the same time, a function of transmitting the light excited by the optical semiconductor element 4 to the optical fiber member 11 is provided. The light transmitting member 10 is attached to the inner end face, and the optical fiber member 11 is attached and connected to the outer end face side. Is done.

The cylindrical fixing member 9 is made of an iron-nickel-cobalt alloy or an alloy of 40 to 60% by weight of iron and 40 to 60% by weight of nickel, for example, an ingot of an iron-nickel-cobalt alloy or the like. The (lumps) are formed by pressing into a tubular shape.

The fixing member 9 has a concave portion 9a on an inner end surface thereof, and a translucent member 10 is attached to the bottom surface of the concave portion 9a. The space is closed, airtight sealing of the container including the base 1, the frame 2, and the lid member 3 is maintained, and the light excited by the optical semiconductor element 4 which transmits the internal space of the fixing member 9 is directly taken to the fixing member 9. Optical fiber member 11 to be connected
It acts to transmit to.

The light transmitting member 10 is made of, for example, silicon oxide,
It is made of lead-based and boric acid containing lead oxide as a main component, and borosilicate-based amorphous glass containing silica sand as a main component.
Since the amorphous glass has no crystal axis, the light excited by the optical semiconductor element 4 is transmitted and received by the optical fiber member 11 through the light-transmitting member 10. The birefringence does not occur in the member 10 and is transmitted / received to the optical fiber member 11 as it is. As a result, the transmission / reception of the light excited by the optical semiconductor element 4 to / from the optical fiber member 11 becomes highly efficient, and the transmission of the optical signal is performed. High efficiency can be achieved.

Further, the light-transmitting member 10 is attached to the fixing member 9 by, for example, previously attaching a metallization layer 12 to the outer periphery of the main surface of the light-transmitting member 10, and attaching the metallization layer 12 to the fixing member 9. This is performed by brazing the bottom surface of the concave portion provided on the inner end surface of the solder paste 9 through a brazing material such as a gold-tin alloy.
In this case, since the attachment of the translucent member 10 to the fixing member 9 is performed by brazing with a gold-tin alloy or the like, the attachment is highly reliable. The hermetic sealing of the container housing the optical semiconductor element 4 at the portion where the optical semiconductor element 4 is attached to the container 10 is completed, and the optical semiconductor element 4 housed inside the container can be normally and stably operated for a long period of time.

The translucent member 10 has a distance of 1 mm between the outer peripheral portion thereof and the inner surface of the concave portion 9a provided on the end surface of the fixing member 9.
The above spacing is provided, so that there is a difference in the coefficient of thermal expansion between the translucent member 10 and the fixing member 9 or between the frame 2 and the fixing member 9. When attaching to the fixing member 9, or when attaching the fixing member 9 to which the translucent member 10 is attached to the through hole 2a of the frame 2, between the translucent member 10 and the fixing member 9, or A thermal stress is generated between the frame body 2 and the fixing member 9 due to a difference in the thermal expansion coefficient between the two, and even if this acts on the translucent member 10 from the outer peripheral portion, the inner surface of the concave portion 9a and the translucent member 10 Since there is an interval of 1 mm or more between the outer periphery and the outer periphery, the stress does not act on the translucent member 10, and as a result, the translucent member 10 does not have thermal stress. Therefore, when the light excited by the optical semiconductor element 4 is transmitted to the optical fiber member 11 through the light transmitting member 10, the light excited by the optical semiconductor element 4 undergoes birefringence due to the thermal stress inherent in the light transmitting member 10. The signal is transmitted to and received from the optical fiber member 11 as it is without causing the transmission, and the transmission efficiency of the optical signal becomes extremely high.

The distance between the outer peripheral portion of the light transmitting member 10 and the inner surface of the concave portion 9a provided on the end surface of the fixing member 9 is 1 mm.
When the value is less than the predetermined value, the thermal stress generated between the translucent member 10 and the fixing member 9 or between the frame 2 and the fixing member 9 is reliably prevented from acting on the outer peripheral portion of the translucent member 10. You can't do that. Therefore, the distance between the outer peripheral portion of the translucent member 10 and the inner surface of the concave portion 9a provided on the end surface of the fixing member 9 is specified to be 1 mm or more.

The fixing member 9 is 40 to 60% by weight.
And 40 to 60% by weight of nickel, the alloy of 40 to 60% by weight of iron and 40 to 60% by weight
Nickel alloy has a thermal expansion coefficient of about 9.5x
10 ⁻⁶ / ° C. (Rt to 400 ° C.), which is close to the coefficient of thermal expansion of the translucent member 10 made of amorphous glass, so that when the translucent member 10 is brazed to the fixing member 9, A thermal stress is generated between the light transmitting member 10 and the fixing member 9 due to a difference in thermal expansion coefficient between the light transmitting member 10 and the fixing member 9.
The optical semiconductor element 4 that is inherent in and passes through the translucent member 10
Does not cause birefringence in the excited light of the optical fiber member 11.
And the transmission efficiency of the optical signal becomes extremely high. Therefore, it is preferable that the fixing member 9 is formed of an alloy of 40 to 60% by weight of iron and 40 to 60% by weight of nickel.

Further, the metallized layer 12 previously coated on the outer periphery of the main surface of the light transmitting member 10 is
Since the melting point of the amorphous glass constituting is as low as about 700 ° C. and cannot be formed by adopting the conventionally known Mo—Mn method, as shown in FIG. And a first layer 12a made of at least one of titanium, titanium-tungsten, and tantalum nitride, which is firmly bonded, and the first layer 12a
Is diffused into a third layer 12c, which will be described later, by heat generated when brazing the fixing member 9 to the light transmitting member 1 of the metallized layer 12.
A second layer 12b made of at least one of platinum, nickel, and nickel-chromium, which effectively prevents a decrease in bonding strength to the metallized layer 12; A third layer 12 made of at least one of gold, platinum, and copper for firmly joining materials and firmly attaching the translucent member 10 to the fixing member 9.
and c are sequentially laminated.
In particular, the metallized layer 12 formed by sequentially laminating titanium-platinum-gold has a strong bonding strength with the translucent member 10 and a good wettability with the brazing material.
Metallization layer 12 because it can be brazed to
Is very suitable.

A first layer 12a made of at least one of titanium, titanium-tungsten and tantalum nitride, a second layer 12b made of at least one of platinum, nickel and nickel-chromium, and at least one of gold, platinum and copper The metallized layer 12 having a three-layer structure with the third layer 12c made of one kind is formed by depositing a metal material or a nitride on the outer periphery of the translucent member 10 by a sputtering method, a vapor deposition method, an ion plating method, or a plating method. It is formed by sequentially applying a predetermined thickness by using the method described above.

Further, the metallized layer 12 includes a first layer 12a made of at least one of titanium, titanium-tungsten, and tantalum nitride, a second layer 12b made of at least one of platinum, nickel, and nickel-chromium; When the third layer 12c made of at least one of platinum and copper is used, if the thickness of the first layer 12a is less than 500 angstroms, the bonding strength of the metallized layer 12 to the translucent member 10 tends to be weak. If the thickness exceeds 2000 angstroms, the first layer 12a
When the first layer 12a is adhered, a large stress is inherent in the first layer 12a, and the first layer 12a is
It is preferable that the thickness of the first layer 12a be in the range of 500 Å to 2000 Å because the layer tends to be more easily peeled off, and the light transmitting member 10 is fixed when the thickness of the second layer 12b is less than 500 Å. It is not possible to effectively prevent the first layer 12a from diffusing into the third layer 12c due to heat when brazing to the member 9, and the bonding strength of the metallized layer 12 to the translucent member 10 is reduced. Dangerous, 100
When the thickness exceeds 00 Å, the second layer is formed on the first layer 12a.
When depositing the layer 12b, a large stress is present in the second layer 12b, and the second layer 12b is caused by the first layer 1
The second layer 12 has a tendency to peel off more easily than the second layer 12a.
The thickness of b is preferably in the range of 500 Å to 10000 Å, and if the thickness of the third layer 12 c is less than 0.5 μm, the metallized layer 1
2 does not significantly improve the wettability of the brazing material, making it difficult to firmly braze and attach the translucent member 10 to the fixing member 9.
When the third layer 12c is deposited on the third layer 12b, a large stress is inherent in the third layer 12c, and the third layer 12c
It is preferable that the thickness of the third layer 12c be in the range of 0.5 μm to 5 μm since the second layer 12c tends to be more easily peeled off than the second layer 12b.

On the other hand, a lid member 3 made of a metal material such as an iron-nickel-cobalt alloy or an iron-nickel alloy is joined to the upper surface of the frame body 2 made of the above-mentioned metal material. The optical semiconductor element 4 is hermetically sealed inside a container including the body 2 and the lid member 3.

The lid member 3 is joined to the upper surface of the frame 2 by, for example, welding such as a seam welding method.

Thus, according to the package for housing an optical semiconductor device of the present invention, the optical semiconductor device 4 is mounted and fixed on the optical semiconductor device mounting portion 1a of the base 1 with the Peltier device 5 and the like interposed therebetween. 4 are electrically connected to the external lead terminals 6 via bonding wires 8, and then the lid member 3 is joined to the upper surface of the frame 2, so that the base 1 and the frame 2
The optical semiconductor element 4 is accommodated in a container including the lid member 3 and the optical fiber element 11.
The optical semiconductor device as a final product is obtained by attaching and connecting the optical semiconductor device 4. Light is excited in the optical semiconductor element 4 by a drive signal supplied from an external electric circuit, and the excited light is transmitted through a light-transmitting material made of amorphous glass. The optical fiber member 11 is used for high-speed optical communication and the like by transmitting and receiving the optical fiber member 11 through the member 10 and transmitting the optical fiber member 11 through the optical fiber.

It should be noted that the present invention is not limited to the above-described embodiment, and various changes can be made without departing from the scope of the present invention. Although fixed to the base 1, it may be fixed to the frame 2.

[0038]

According to the package for housing an optical semiconductor element of the present invention, the light-transmitting member is provided on the bottom surface of the concave portion provided on the end surface of the fixing member, at least 1 mm between the inner surface of the concave portion and the outer periphery of the light-transmitting member. Fixed at a certain distance, there is a difference in the coefficient of thermal expansion between the translucent member and the fixing member, or between the frame and the fixing member. When the fixing member having the translucent member is attached to the through hole of the frame, the thermal expansion coefficient between the translucent member and the fixing member, or between the frame and the fixing member. Thermal stress is generated due to the difference between the light transmitting member and the outer peripheral portion. Even if the thermal stress is caused to act on the translucent member, the stress is transmitted because there is a distance of 1 mm or more between the inner surface of the concave portion and the outer periphery of the translucent member. It does not act on the light-transmitting member, and as a result, there is no thermal stress inherent in the light-transmitting member. . Therefore, when the light excited by the optical semiconductor element is transmitted to the optical fiber through the translucent member, the light excited by the optical semiconductor element does not cause birefringence due to the thermal stress inherent in the translucent member. The transmission and reception are performed between the members, and the transmission efficiency of the optical signal becomes extremely high.

[Brief description of the drawings]

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

FIG. 2 is an enlarged sectional view of a main part of the package for housing an optical semiconductor element shown in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Base | substrate 1a ... Optical semiconductor element mounting part 2 ... Frame 2a ... Through-hole 3 ... Lid member 4: ... Optical semiconductor element 9 ... Fixing member 9a ... Depression 10 ... ..Translucent members 11 ... Optical fiber members

Claims (1)

[Claims] 1. A frame having a mounting portion on which an optical semiconductor device is mounted on an upper surface, and a frame attached to the substrate so as to surround the optical semiconductor device mounting portion and having a through hole on a side portion. Body, a cylindrical fixing member attached to a through hole of the frame body, and having a space in which an optical signal is transmitted, and attached to an end face of the cylindrical fixing member, and the inside of the fixing member A translucent member to close,
A lid member attached to an upper surface of the frame body and a lid member for hermetically sealing the optical semiconductor element, wherein the fixing member has a concave portion on an end surface and has a light transmitting surface on the concave bottom surface. An optical semiconductor element housing package, wherein a transparent member is attached, and a gap of 1 mm or more is formed between the inner surface of the concave portion and the outer periphery of the light transmitting member.