JP3526518B2 - Optical semiconductor element storage package - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical semiconductor device housing package for housing an optical semiconductor device, and more particularly, to an optical semiconductor device housing with an improved lens member fixing structure. It is related to a package for use. 2. Description of the Related Art Conventionally, a package for housing an optical semiconductor device for housing an optical semiconductor device is generally made of iron-nickel-cobalt alloy or copper-tungsten as shown in a sectional view in FIG. An optical semiconductor element 24 is provided at the center of the upper surface with a mounting portion 21a on which the optical semiconductor element 24 is mounted via a Peltier element 25. A plurality of external lead terminals 26 are provided around the mounting portion 21a as insulating members. A base 21 fixed so as to penetrate from the upper surface to the lower surface via 27, and a mounting portion 21 on the base 21
a frame 22 made of a metal such as an iron-nickel-cobalt alloy having a through hole 22a on the side, and being inserted and fixed in the through hole 22a of the frame 22, An optical fiber 30 for transmitting and receiving an optical signal between the semiconductor element 24 and the outside is inserted and fixed to the outer end of the frame 22 and a cylindrical metal fixing member 29 made of a metal such as an iron-nickel-cobalt alloy is provided. A cylindrical lens member 31 which is inserted and fixed to the inner end of the frame 22 of the metal fixing member 29 and airtightly partitions the inside and outside of the frame 22;
And a lid 23 that hermetically seals it. Then, the optical semiconductor element 24 is bonded and fixed to the mounting portion 21a of the base 21, and each electrode of the optical semiconductor element 24 is electrically connected to the external lead terminal 26 via the bonding wire 28,
Thereafter, the lid 23 is joined to the upper surface of the frame 22 to mainly
An optical semiconductor element is placed inside a container comprising a frame 21, a frame 22, and a lid 23.
An optical semiconductor device as a product is obtained by housing the airtight airtight 24 and inserting and fixing the optical fiber 30 inside the metal fixing member 29. In such an optical semiconductor device, the optical semiconductor element 24 is excited by a drive signal supplied from an external electric circuit, and the excited light is transmitted to and received from the optical fiber 30 through the cylindrical lens member 31. By transmitting the light inside, it functions as an optical semiconductor device used for high-speed optical communication or the like. The cylindrical lens member 31 is made of a glass material having a lens function by changing the refractive index from its central axis toward the outer periphery, and is made of a metal fixing member.
Insertion and fixing to the 29
A metal thin film made of t · Au is applied, inserted into the metal fixing member 29, and the metal thin film applied to the outer peripheral surface of the cylindrical lens member 31 and a metal fixing member opposed thereto are attached. This is performed by brazing the inner peripheral surface of the member 29 via a brazing material made of a gold-copper alloy or the like. However, in this conventional package for housing an optical semiconductor element, the thermal expansion coefficient of the iron-nickel-cobalt alloy constituting the metal fixing member 29 (about 6 × 10 ^{−). 6} / ° C.) and the thermal expansion coefficient (about 10 × 10 ⁻⁶ / ° C.) of the glass constituting the cylindrical lens member 31 and that the entire outer peripheral surface of the cylindrical lens member 31 is brazed. For example, when brazing the outer peripheral surface of the cylindrical lens member 31 to the inner peripheral surface of the metal fixing member 29 via a brazing material such as a gold-tin alloy, the cylindrical lens member 31 and the metal fixing member 29 During this time, a large thermal stress is generated due to the difference between the two thermal expansion coefficients, and this thermal stress directly acts on the corner between the outer peripheral surface and the end surface of the cylindrical lens member 31. Then, since stress is easily concentrated at the corners, stress is greatly concentrated at the corners, and the stress is embedded therein.If the heat generated during operation of the optical semiconductor element 24 is repeatedly applied thereto, This thermal stress is synergistic with the stress inherent in the corners to cause cracks in the columnar lens member 31 starting from the corner between the outer peripheral surface and the end surface of the columnar lens member 31. As a result, when the light excited by the optical semiconductor element 24 is transmitted to the optical fiber 30 via the cylindrical lens member 31, irregular reflection of light occurs in the cylindrical lens member 31, and the light excited by the optical semiconductor element 24 is circularly reflected. Columnar lens member
It becomes impossible to transmit and receive the optical semiconductor device 30 properly through the optical fiber 30, or the crack generated in the cylindrical lens member 31 breaks the airtightness of the optical semiconductor device housing package, and the optical semiconductor device housed inside 24 has a disadvantage that it cannot be operated normally and stably for a long period of time. SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to generate cracks in a cylindrical lens member even when heat generated during operation of an optical semiconductor element housed therein is repeatedly applied. The optical semiconductor device can transmit and receive light excited by the optical semiconductor device to and from the optical fiber via the cylindrical lens member without causing the optical semiconductor device to operate normally and stably for a long period of time. It is an object of the present invention to provide a package for housing an optical semiconductor element that can be used. According to the present invention, there is provided a package for storing an optical semiconductor element, comprising: a base having a mounting portion on which an optical semiconductor element is mounted on an upper surface; A frame body that is attached so as to surround it and has a through hole on the side, and is inserted and fixed in the through hole, an optical fiber is inserted into the outer end of the frame, and a cylindrical lens member is inserted into the inner end. An optical semiconductor element housing package comprising: a cylindrical metal fixing member to be fixed; and a lid attached to an upper surface of the frame body and hermetically sealing the optical semiconductor element. The fixing member has a ring-shaped protrusion having a width shorter than the length of the cylindrical lens member on the inner peripheral surface thereof, and both ends of the cylindrical lens member are 0.3 m from the ring-shaped protrusion.
The center portion of the outer peripheral surface is fixed to the inner peripheral surface of the ring-shaped protrusion via a brazing material so as to protrude by m or more. According to the optical semiconductor element housing package of the present invention, the cylindrical lens member has both ends protruding from the ring-shaped protrusion by 0.3 mm or more, and the central portion of the outer peripheral surface is interposed with the brazing material. When the cylindrical lens member is brazed to the metal fixing member, since the outer peripheral surfaces near both ends within 0.3 mm from both ends are not brazed. Does not act directly on the corners between the outer peripheral surface and the end surface of the cylindrical lens member, and therefore, the stress at the time of brazing does not largely concentrate on the corners. Next, the present invention will be described in detail with reference to the accompanying drawings. 1 and 2 are cross-sectional views showing an example of an embodiment of the package for housing an optical semiconductor element of the present invention. In FIG. 1, reference numeral 1 denotes a base, 2 denotes a frame, and 3 denotes a lid. These mainly constitute a container for housing the optical semiconductor element 4. The base 1 functions 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. 1
The optical semiconductor element 4 is bonded and fixed to a by 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. It is manufactured by applying a conventionally known metal working method such as The base 1 is provided with a metal having excellent corrosion resistance and excellent wettability with a brazing material, specifically, a nickel layer having a thickness of 2 to 6 μm and a gold layer having a thickness of 0.5 to 5 μm on its outer surface. If they are sequentially applied by plating, oxidation and corrosion of the base 1 can be effectively prevented, and the Peltier element 5 and the like disposed below the optical semiconductor element 4 are firmly adhered and fixed to the upper surface of the base 1. Can be done. Therefore, the base 1 has a nickel layer having a thickness of 2 to 6 μm on its outer surface.
It is preferable that a gold layer of 0.5 to 5 μm is sequentially applied by a plating method. The base 1 has a plurality of external lead terminals 6 penetrating the base 1 around an installation portion 1a on which the optical semiconductor element 4 is mounted, and is fixed via an insulating member 7 such as glass. I have. The external lead terminal 6 serves to electrically connect the electrodes of the optical semiconductor element 4 to an external electric circuit. One end of the external lead terminal 6 is connected to the electrode of the optical semiconductor element 4 via a bonding wire 8. The other end is connected to a wiring conductor of the external electric circuit board via solder. The external lead terminal 6 is made of a metal material such as an iron-nickel-cobalt alloy or an iron-nickel alloy. The external lead terminal 6 is fixed to the base 1 by opening a hole having a diameter slightly larger than that of the external lead terminal 6. The ring-shaped insulating member 7 made of glass and the external lead terminals 6 are inserted through the holes, and then the insulating member 7 made of glass is heated and melted. The external lead terminal 6 is provided with a metal layer having excellent corrosion resistance such as a nickel plating layer or a gold plating layer on its surface, excellent connectivity with the bonding wire 8 and excellent wettability with solder having a thickness of 1 to 20 μm. In this case, oxidation corrosion of the external lead terminal 6 is effectively prevented, and connection between the external lead terminal 6 and the bonding wire 8 and connection between the external lead terminal 6 and the external electric circuit are easily and firmly performed. Can be done. Therefore, the external lead terminal 6 has a plated metal layer having excellent corrosion resistance such as a nickel plating layer or a gold plating layer on its surface, excellent connectivity with the bonding wire 8 and excellent wettability with the solder of 1 to 20 μm.
It is preferable to adhere to a thickness of. Further, the optical semiconductor element 4 is provided on the upper surface of the base 1.
The frame 2 is joined so as to surround the mounting portion 1a on which the optical semiconductor element 4 is mounted, 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. The frame 2 is formed in a predetermined shape, and the attachment of the frame 2 to the base 1
This is performed by brazing the lower surface with a brazing material such as silver brazing. The frame 2 is provided with a through hole 2a on the side thereof, and a cylindrical metal fixing member 9 is inserted and fixed in the through hole 2a. An optical fiber 10 is inserted into and fixed to the metal fixing member 9 from the outer end of the frame 2 so as to face the optical semiconductor element 4. Optical signals can be transmitted and received between them. The fixing of the optical fiber 10 to the metal fixing member 9 is performed as follows.
For example, this is performed by laser welding a metal flange 10a previously attached to the optical fiber 10 to the outer end of the metal fixing member 9. The metal fixing member 9 is made of a metal material such as an iron-nickel-cobalt alloy or an iron-nickel alloy, and is inserted through a through hole 2 a provided in a side portion of the frame 2.
A part of the outer peripheral surface is fixed to the frame 2 by brazing the frame 2 with a brazing material such as silver brazing. The metal fixing member 9 is provided with a metal layer having excellent corrosion resistance, such as nickel or gold, on its surface by plating.
When the metal fixing member 9 is adhered to a thickness of 20 μm, the metal fixing member 9 can be effectively prevented from being oxidized and corroded. Therefore, it is preferable that a metal having excellent corrosion resistance, such as nickel or gold, is applied to the surface of the metal fixing member 9 to a thickness of 1 to 20 μm. Further, as shown in FIG. 2 in an enlarged sectional view of a main part of FIG. 1, the metal fixing member 9 has a predetermined height on the inner peripheral surface of the inner end of the frame 2 over the entire circumference toward the central axis. And a ring-shaped protrusion 9a having a width shorter than the length of a cylindrical lens member 11 described later is provided.
In reference numeral 11, only the central portion of the outer peripheral surface is fixed to the inner peripheral surface of the ring-shaped protrusion 9a via a brazing material. Since the metal fixing member 9 has a ring-shaped protrusion 9a having a width shorter than the length of the cylindrical lens member 11 on the inner peripheral surface thereof, the cylindrical lens member 9 will be described later.
By inserting both ends of the cylindrical lens member 11 out of the ring-shaped protruding portion 9a at the time of inserting the 11 into the metal fixing member 9 via a brazing material, only the central portion of the outer peripheral surface is brazed and fixed, It becomes easy to fix the outer peripheral surfaces near both ends of the cylindrical lens member 9 without brazing. The cylindrical lens member 11 inserted into and fixed to the metal fixing member 9 is made of glass, and has a lens function by changing its refractive index from the central axis toward the outer peripheral side. It seals the inside space of the metal fixing member 9 to maintain the airtightness of the container, and transmits and condenses the light excited by the optical semiconductor element 4 housed in the container to form an optical fiber 10. It acts to give and receive. The cylindrical lens member 11 is inserted and fixed in the metal fixing member 9 so that both ends protrude from the ring-shaped protrusion 9a of the metal fixing member 9, and the vicinity of both ends is removed. Only the central portion of the outer peripheral surface is brazed and fixed to the inner peripheral surface of the ring-shaped protrusion 9a of the metal fixing member 9 via a brazing material such as a gold-tin alloy. Since the outer peripheral surfaces near both ends of the cylindrical lens member 11 are not brazed, when the cylindrical lens member 11 is brazed to the metal fixing member 9, the stress of the brazing is reduced. The voltage is not directly applied to the corner between the end surface of the member 11 and the outer peripheral surface. Therefore, a large stress does not concentrate and exist inside the corner, and even if a stress due to heat generated during operation of the optical semiconductor element 4 is repeatedly applied, this stress is synergistic with the above-described intrinsic stress. As a result, no crack is generated in the cylindrical lens member 11. In order to braze the cylindrical lens member 11 to the metal fixing member 9, a metal thin film made of Ti, Pt, or Au is coated on the outer peripheral surface of the cylindrical lens member 11 by a conventionally known vapor deposition method or sputtering method. The metal thin film and the metal fixing member 9
Is adopted by brazing the inner peripheral surface of the ring-shaped protrusion 9a with a brazing material such as a gold-tin alloy. If the width of both ends of the cylindrical lens member 11 protruding from the ring-shaped protrusion 9a of the metal fixing member 9 is less than 0.3 mm, the cylindrical lens member 11 will be attached to the metal fixing member 9. At the time of brazing, a pool of brazing material reaches a corner between the end face and the outer peripheral surface of the cylindrical lens member 11, and as a result, the brazing stress acts directly on this corner and is largely contained therein. There is a tendency that cracks are easily generated in the cylindrical lens member 11 in synergy with thermal stress due to heat generated when the semiconductor element 4 operates. Therefore, the cylindrical lens member 11 is fixed such that both ends thereof protrude from the ring-shaped protrusion 9a of the metal fixing member 9 by 0.3 mm or more. On the other hand, a lid 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 2, whereby the base 1 and the frame 2 are joined together. The optical semiconductor element 4 is hermetically sealed inside the container including the lid 3. The lid 3 is joined to the upper surface of the frame 2 by a welding method such as a seam welding method. Thus, according to the optical semiconductor element housing package of the present invention, the optical semiconductor element 4
Are mounted and fixed with a Peltier element 5 or the like in between, and each electrode of the optical semiconductor element 4 is electrically connected to an external lead terminal 6 via a bonding wire 8. 3 and the optical semiconductor element 4 is accommodated in a container consisting of the base 1, the frame 2 and the lid 3, and finally the frame 2
The optical fiber 10 is inserted into and fixed to the metal fixing member 9 which is inserted and fixed into the optical semiconductor device. The optical semiconductor device as a final product is obtained. Light is excited in the optical semiconductor element 4 by a drive signal supplied from an external electric circuit. The excited light is condensed and transmitted to and from the optical fiber 10 through the cylindrical lens member 11 and is transmitted through the optical fiber 10 for use in high-speed optical communication and the like. It should be noted that the present invention is not limited to the above embodiment, and various changes can be made without departing from the gist of the present invention. For example, in the above embodiment, the external lead terminals 6 are fixed to the base 1, but may be fixed to the frame 2. According to the package for housing an optical semiconductor element of the present invention, the cylindrical lens member is formed such that both ends thereof protrude from the ring-shaped projection by 0.3 mm or more, and the central portion of the outer peripheral surface is made of metal. The cylindrical lens member is made of metal because the inner peripheral surface of the ring-shaped protrusion of the fixing member is fixed via brazing material, and the outer peripheral surface near both ends within 0.3 mm from both ends is not brazed. When brazing to the fixing member, the stress caused by brazing does not directly act on the corner between the outer peripheral surface and the end surface of the cylindrical lens member. Therefore, the stress does not largely concentrate on the corners and is not present therein. Even if heat generated during operation of the optical semiconductor element is repeatedly applied thereto, the stress due to the heat is synergistic with the above-mentioned inherent stress. Cracks do not occur in the cylindrical lens member. As a result, the light excited by the optical semiconductor element can be favorably transmitted to and received from the optical fiber via the cylindrical lens member, and the optical semiconductor element housed therein can operate normally and stably for a long period of time.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view showing an example of an embodiment of an optical semiconductor element housing package 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; FIG. 3 is a sectional view of a conventional package for housing an optical semiconductor element. [Description of Signs] 1 Base 1a Mounting part 2 Frame 2a Through hole 3 Lid 4 Optical semiconductor element 9 Metal fixing member 9a・ Ring-shaped protrusion 10 ・ ・ ・ Optical fiber 11 ・ ・ ・ Cylindrical lens member

Claims (1)

(57) Claims 1. A base having a mounting portion on which an optical semiconductor element is mounted on an upper surface, and a base attached to the upper surface of the base so as to surround the mounting portion. A frame having a through-hole in a portion thereof, and a cylindrical metal fixing which is inserted and fixed in the through-hole, an optical fiber is inserted in an outer end of the frame, and a cylindrical lens member is inserted and fixed in an inner end. and member, is attached to the upper surface of the frame, the optical semiconductor device comprising an optical semiconductor element storage package comprising a lid for sealing hermetically, said metal securing member
Is shorter than the length of the cylindrical lens member on its inner peripheral surface.
A ring-shaped protrusion having a width, wherein both ends of the cylindrical lens member are 0.3 mm or less from the ring-shaped protrusion.
The central part of the outer peripheral surface is
An optical semiconductor element storage package, which is fixed to an inner peripheral surface of a protruding portion via a brazing material.