JP2003222767A - Storing package for optical semiconductor element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make transmission characteristics of the inside of an optical fiber of a laser beam oscillated from an optical semiconductor element and airtightness of the inside of an optical semiconductor element storing package excellent by surely forming an effective diameter for transmitting a sufficient amount of light with a reflection preventive film on the surface of a spherical transmission member. <P>SOLUTION: A holding member 3c of a substantially disk-like transmission member 3a joining an outer peripheral part to an end face 3b of the outside of a frame body 2 of a cylindrical optical fiber fixed member 3 has a chamfered part of 45 degrees or greater of an angle at which a ridge part between an inner peripheral face of the cylindrical part and a main face of the outside of the frame body 2 is directed to the inner peripheral face of the cylindrical part. An interval between the outer peripheral face of the cylindrical part and the inner peripheral face of the optical fiber fixed member 3 is 0.5 or greater. <P>COPYRIGHT: (C)2003,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor laser (L)
D) and an optical semiconductor element housing package for housing an optical semiconductor element such as a photodiode (PD). FIG. 2 shows a conventional package for housing an optical semiconductor element (hereinafter, also referred to as an optical semiconductor package).
As shown in the figure, the optical semiconductor package has LD, P
D and the like are formed of an iron (Fe) -nickel (Ni) -cobalt (Co) alloy or a copper (Cu) -tungsten (W) alloy having a mounting portion 101a on which an optical semiconductor element 105 is mounted. A frame having a plate-shaped body 101 and a through-hole 102a attached to the base 101 via a brazing material such as silver brazing so as to surround the mounting portion 101a, and for transmitting and receiving an optical signal. Body 102 and an optical semiconductor element joined to the upper surface of the frame body 102
It mainly comprises a lid 104 for hermetically sealing 105. On the side of the frame 102, there is provided a cylindrical optical fiber fixing member (hereinafter also referred to as a fixing member) 103 which is fitted and joined to the through hole 102a of the frame 102. Further, the fixing member 103 is provided with a holding member 103c of a translucent member 103a having an outer peripheral portion joined to an end surface on the outside of the frame body 102 and having a cylindrical portion 103c at a central portion. A spherical translucent member 103a for a condenser lens or the like is attached inside the cylindrical portion of the holding member 103c. Further, on the other side of the frame 102, an attachment portion for an input / output terminal formed of a through hole or a notch is formed, and an input / output terminal for inputting / outputting a high-frequency signal for driving to / from the optical semiconductor element 105 is provided. (Ceramic terminal) (not shown) is attached. The input / output terminal has a line conductor formed of a metallized layer for leading the inside and outside of the frame 102, and an external lead terminal is connected to a portion of the line conductor outside the frame 102. [0004] An optical semiconductor element 105 is bonded and fixed to a mounting portion 101a of a base 102 via a base 108 on which a circuit board or the like is mounted, and each electrode of the optical semiconductor element 105 is input / output via a bonding wire. By connecting to the line conductor of the terminal, it is electrically connected to the external lead terminal.
A lid 104 is attached to the upper surface of 2, the base 101, the frame 102, and the lid 10
The optical semiconductor element 105 is housed inside the container made of 4 and finally, a flange 107 made of stainless steel attached to the end of the optical fiber 106 is joined to the fixing member 103 by laser welding by irradiation with YAG laser light. And optical fiber
By fixing 106 to fixing member 103, an optical semiconductor device as a product is obtained. In this optical semiconductor device, light is excited in the optical semiconductor element 105 by a drive signal supplied from an external electric circuit, and the excited light is transmitted to the outside via an optical fiber 106, thereby achieving high-speed communication. used. Incidentally, such an optical semiconductor package is
Gold (Au) plating is preliminarily applied to the surfaces of the base 101 and the frame 102 to effectively prevent oxidative corrosion of the base 101 and the frame 102 and to firmly join the optical semiconductor element 105 to the mounting portion 101a. can do. However, in the above-mentioned conventional optical semiconductor package, since the opening of the outer main surface of the cylindrical portion 102 of the cylindrical portion of the holding member 103c is small, a light transmitting member is formed on the holding member 103c. There is a problem that it is difficult to form an anti-reflection film on the translucent member 103a from the opening side by a thin film forming method such as a sputtering method with the 103a bonded. That is, even if an anti-reflection film is formed by injecting a thin film material from the opening side in the thin film forming apparatus, the effective diameter is such that the light is sufficiently transmitted to the surface of the light transmitting member 103a because the opening is small. No anti-reflection film is formed. When the translucent member 103a is joined to the inside of the cylindrical portion with low melting glass, and the outer peripheral portion of the holding member 103c is joined to the end surface 103b of the fixing member 103 outside the frame 102 with low melting point brazing material. In addition, the brazing material easily accumulates on the outer peripheral surface of the cylindrical portion near the translucent member 103a. As a result, the translucent member 103
There is a problem that a large stress is applied to a through the accumulation of the brazing material, and the translucent member 103a comes off or the airtightness in the optical semiconductor package is broken. In addition, the stress applied to the light-transmitting member 103a causes distortion in the light-transmitting member 103a, causing birefringence or refractive index distribution in the light-transmitting member 103a, changing the focus and the like, and deteriorating optical characteristics. There were also points. Accordingly, the present invention has been completed in view of the above problems, and an object of the present invention is to form and fix an antireflection film on the surface of a light transmitting member with an effective diameter capable of transmitting a sufficient amount of light. When the outer peripheral portion of the holding member is joined to the end surface of the member with a low melting point brazing material, stress is applied and the light transmitting member is detached,
An object of the present invention is to solve the problem that airtightness in an optical semiconductor package is broken. Further, by preventing the light transmitting member from being distorted due to the stress applied to the light transmitting member and causing the birefringence or the distribution of the refractive index to occur in the light transmitting member and changing the focal point and the like, and thereby deteriorating the optical characteristics. Another object of the present invention is to improve transmission characteristics of an optical fiber such as a laser beam emitted from an optical semiconductor element in an optical fiber and airtightness in an optical semiconductor package. And
An object of the present invention is to provide an optical semiconductor package capable of operating an optical semiconductor element normally and stably for a long period of time. A package for containing an optical semiconductor element according to the present invention has a base having a mounting part on which an optical semiconductor element is mounted on an upper surface, a through hole on a side part, and A frame attached to the upper surface of the base so as to surround the mounting portion, a cylindrical optical fiber fixing member fitted into the through hole, and an end face of the optical fiber fixing member outside the frame; A holding member of a substantially disc-shaped translucent member having an outer peripheral portion joined to a central portion and a cylindrical portion protruding inward of the frame at a central portion, and an inner peripheral surface of the cylindrical portion of the holding member An optical semiconductor element housing package comprising a spherical translucent member joined to the holding member, wherein the holding member has a ridge between an inner peripheral surface of the cylindrical portion and a main surface outside the frame. The angle to the inner peripheral surface of the cylindrical part is a chamfered part of 45 ° or more, One gap between the inner peripheral surface of the outer peripheral surface of the cylindrical portion and the optical fiber fixing member is equal to or is 0.5mm or more. According to the package for storing an optical semiconductor element of the present invention, an antireflection film having an effective diameter capable of transmitting a sufficient amount of light on the surface of a light-transmitting member can be surely formed and the light-transmitting member can be formed. When the member is joined to the holding member with low-melting glass, stress is applied when the outer peripheral portion of the holding member is joined to the end surface of the fixing member with a low-melting brazing material, the light-transmitting member comes off, or the inside of the optical semiconductor package is removed. The problem that airtightness is broken can be solved. Further, it is possible to prevent the light transmitting member from being distorted due to the stress applied to the light transmitting member, causing birefringence or refractive index distribution to occur in the light transmitting member, and changing the focal point and the like, thereby deteriorating the optical characteristics. By suppressing this, the transmission characteristics of the light oscillated from the optical semiconductor element in the optical fiber and the airtightness inside the optical semiconductor package can be improved. As a result, an optical semiconductor package capable of operating the optical semiconductor element normally and stably for a long period of time can be provided. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The package for housing an optical semiconductor device according to the present invention will be described in detail below. FIG. 1 is a sectional view of an optical semiconductor package of the present invention. As shown in the figure, the optical semiconductor package of the present invention has LD, PD
Having a mounting portion 1a on which an optical semiconductor element 5 such as
A base 1 which is made of an e-Ni-Co alloy or a Cu-W alloy and is a substantially rectangular plate-like body, and is attached to an upper surface of the base 1 with a brazing material such as silver brazing so as to surround the mounting portion 1a. Frame 2 having a through hole 2a for transmitting and receiving an optical signal;
And a lid 4 hermetically sealed to the optical semiconductor element 5. At the side of the frame 2, a cylindrical fixing member 3 is fitted and joined into the through hole 2a of the frame 2, and the outer periphery of a substantially disk-shaped holding member 3c is joined to the end face 3b. Is provided, and a spherical translucent member 3a for a condenser lens or the like is attached inside the cylindrical portion of the holding member 3c. An input / output terminal (ceramic terminal) for inputting / outputting a driving high-frequency signal to / from the optical semiconductor element 5 is provided on the other side of the frame body 2 at an input / output terminal mounting portion formed of a through hole or a notch.
(Not shown) is attached. The input / output terminal has a line conductor made of a metallized layer that conducts inside and outside the frame 2, and an external lead terminal is joined to a portion of the line conductor outside the frame 2. An optical semiconductor element 5 is bonded and fixed to a mounting portion 1a of the base 1 via a base 8 on which a circuit board or the like is mounted, and each electrode of the optical semiconductor element 5 is input / output via a bonding wire. It is electrically connected to the external lead terminal by being connected to the line conductor of the terminal, and then the lid 4 is attached to the upper surface of the frame 2, and the inside of the container comprising the base 1, the frame 2 and the lid 4 The optical semiconductor element 5 is housed in the housing. The substrate 1 of the present invention is made of an Fe—Ni—Co alloy, a sintered material of Cu—W, or the like, and its ingot (lumps).
It is manufactured into a predetermined shape by applying a conventionally known metal working method such as rolling or punching, or by performing injection molding and cutting. In the approximate center of the upper surface, LD,
A mounting portion 1a for mounting an optical semiconductor element 5 such as a PD via a base 8 is provided, and the optical semiconductor element 5 is bonded to the upper surface of the mounting portion 1a by a bonding material such as solder. The base 8 is mounted and fixed via an adhesive, a low-melting glass, a solder or the like. The electrode of the optical semiconductor element 5 is electrically connected to the line conductor of the input / output terminal via a bonding wire or the like. The substrate 1 is formed by depositing a metal having excellent corrosion resistance and excellent wettability of the brazing material, specifically, a Ni layer having a thickness of 0.5 to 9 μm and an Au layer having a thickness of 0.5 to 5 μm on a surface thereof by plating. It is preferable to prevent the oxidation and corrosion of the substrate 1 effectively. On the outer peripheral portion of the upper surface of the base 1, a mounting portion 1 is provided.
The frame 2 is erected so as to surround a. The frame 2 together with the base 1 forms a space for accommodating the optical semiconductor element 5 inside. The frame 2 is made of Fe—Ni similarly to the base 1.
-Made of a metal such as a Co alloy or a sintered material of Cu-W and brazed by being integrally formed with the base 1 or brazing the base 1 through a brazing material such as silver brazing; By being joined by a welding method, it is erected on the outer periphery of the upper surface of the base 1. The frame 2 is formed by depositing a metal having excellent corrosion resistance and excellent wettability of the brazing material, specifically, a Ni layer having a thickness of 0.5 to 9 μm and an Au layer having a thickness of 0.5 to 5 μm on the surface thereof by plating. It is preferable to prevent oxidation of the frame 2 effectively. A mounting portion for an input / output terminal is formed on a side portion of the frame 2, and the mounting portion is used for inputting and outputting a high-frequency signal between the optical semiconductor element 5 and an external electric circuit, and for connecting the optical semiconductor device. An input / output terminal having a function of sealing the inside and outside of the package airtight is joined with a brazing material such as silver brazing via a metallized layer formed on the terminal. The frame 2 has a through hole 2a on the other side, and a cylindrical fixing member 3 is fitted and joined to the through hole 2a. The fixing member 3 has an outer peripheral surface hermetically bonded with a brazing material such as silver brazing, and an optical fiber 6 is bonded via a flange 7 so as to face the optical semiconductor element 5. An optical signal is exchanged with the optical semiconductor element 5. This fixing member 3 is made of Fe
Frame 2 made of an Ni—Co alloy, an Fe—Ni alloy, or the like.
The holding member 3c of the translucent member 3a is joined to the outer end surface 3b, and the main surface of the holding member 3c outside the frame 2 has a flange 7
Is fixed. The holding member 3c is joined with a low melting point brazing material made of an Au-Sn (tin) alloy or the like. The fixing member 3 is made of a metal having excellent corrosion resistance and excellent wettability of the brazing material, specifically 0.5 to 9 μm.
It is preferable that a m layer of Ni and an Au layer having a thickness of 0.5 to 5 μm are sequentially applied by a plating method, so that oxidation corrosion of the fixing member 3 can be effectively prevented. In addition, a spherical translucent member 3a is joined to the end inside the frame 2 inside the cylindrical portion of the holding member 3c via a low-melting glass. This translucent member 3
“a” is made of amorphous glass, and the joint with the cylindrical portion is joined with low-melting glass. A substantially circular light transmitting portion centered on the optical axis of the optical semiconductor element 5 on the surface of the light transmitting member 3a has an antireflection film whose thickness and refractive index are appropriately selected according to the wavelength of the transmitted optical signal. A membrane has been applied. As shown in FIG. 3, the holding member 3c has a ridge between the inner peripheral surface of the cylindrical portion and the main surface on the outside of the frame 2 having an angle θ of 45 ° or more with respect to the inner peripheral surface of the cylindrical portion. It is a chamfer. If the angle is less than 45 °, it is difficult to reliably form the anti-reflection film with an effective diameter capable of transmitting a sufficient amount of light on the surface of the light transmitting member 3a. Also, the angle θ is preferably 85 ° or less,
If the angle exceeds 85 °, the chamfered portion becomes substantially parallel to the main surface of the holding member 3c outside the frame 2, so that it is difficult to form an antireflection film having an effective diameter. The distance X between the outer peripheral surface of the cylindrical portion of the holding member 3c and the inner peripheral surface of the fixing member 3 is 0.5 mm or more. If it is less than 0.5 mm, the translucent member 3a is attached to the holding member 3c.
When the outer peripheral portion of the holding member 3c is joined to the end surface 3b of the fixing member 3 with the low melting point brazing material,
A brazing material pool is formed between the outer peripheral surface of the cylindrical portion of the holding member 3c and the inner peripheral surface of the fixing member 3, and this gap is easily filled with the brazing material. Then, the stress generated due to the difference in the thermal expansion coefficient between the fixing member 3, the holding member 3c, and the low melting point brazing material is applied to the translucent member 3a, and the translucent member 3a comes off or cracks occur in the translucent member 3a. appear. As a result, the airtightness of the optical semiconductor package itself is broken. Further, the interval X is preferably 3 mm or less, and if it exceeds 3 mm, the optical semiconductor package itself tends to be large in weight. An embodiment of the package for housing an optical semiconductor device according to the present invention will be described below. First, the optical semiconductor package of the present invention shown in FIG. 1 was manufactured in the following steps [1] to [6]. [1] About 13 mm in length × about 30 mm in width × about 1 in thickness
mm-Cu-W alloy, the outer periphery of the upper surface of the substantially square base 1 is about 13 mm long and about 13 mm wide so as to surround the mounting portion 1a.
A frame 2 made of a 20 mm Fe-Ni-Co alloy and having a substantially square shape in plan view was joined with a silver braze. A Ni plating layer having a thickness of about 2 μm and an Au plating layer having a thickness of about 0.5 μm are sequentially deposited on the surfaces of the base 1 and the frame body 2.
A mounting portion for the input / output terminal is formed on a side portion of the frame 2, and a circular through hole 2a is formed on another side portion adjacent to the side portion. [2] Attaching the input / output terminals of the frame 2 is made of alumina ceramics and has a thickness of about 2 μm on the Mo-Mn metallized layer so as to conduct inside and outside the frame 2.
An input / output terminal having a line conductor formed by sequentially depositing a Ni plating layer of m and an Au plating layer of about 0.5 μm in thickness,
Fitted and joined with silver brazing. [3] Fe-Ni-
A cylindrical fixing member 3 made of a Co alloy is fitted and joined with silver brazing, and a spherical translucent member 3a made of amorphous glass is provided inside the cylindrical portion of the fixing member 3 on an end surface 3b outside the frame 2. The outer peripheral portion of the holding member 3c in which
The joint was made with a Sn alloy brazing material. The surface of the fixing member 3 has a Ni plating layer having a thickness of about 2 μm and a thickness of about 0.5 μm
Au plating layers are sequentially applied. [4] The optical semiconductor element 5, which is an LD, is mounted and joined with an Au-Si brazing material to the upper surface of a base 8 made of alumina ceramic adhered on the mounting portion 1a. Were connected to the inside of the line conductor frame 2 of the input / output terminal by a bonding wire. [5] The optical fiber 6 is attached to the main surface of the holding member 3 which is joined to the end surface 3b of the fixing member 3 outside the frame 2.
The holder 7 having one end thereof bonded with a resin adhesive is
It was joined by laser welding to form an optical semiconductor package. [6] The lid 4 made of an Fe-Ni-Co alloy was joined to the upper surface of the frame 2 by seam welding to form an optical semiconductor device. As in the above step [3], a diameter of about 2 m
The angle θ of the chamfer shown in FIG. 3 was 35 ° (sample A), 40 ° (sample B), and 45 ° for the individual holding member 3c in which the m-shaped light-transmitting member 3a was joined with low-melting glass.
(Sample C), 50 (Sample D) °, and 55 ° (Sample E), five types of ten holding members 3c were manufactured.
With respect to these holding members 3c, antireflection films were formed on both sides (the inside of the frame 2 and the outside of the frame 2) of the translucent member 3a, and the state of formation of the antireflection films was confirmed. As a result, in Samples C to E, the anti-reflection film was formed satisfactorily in such a large area that the effective diameter (about 1 mm) was equal to or larger on both sides for 10 out of 10 samples. In Samples A and B, 10 out of 10 anti-reflection films could not be formed on the outer surface of frame 2 of translucent member 3a. Next, in the optical semiconductor device manufactured by the above steps [1] to [6], the angle θ of the chamfered portion is 45 °.
(Sample C) is the holding member 3c, wherein the distance X between the outer peripheral surface of the cylindrical portion and the inner peripheral surface of the fixing member 3 is 0.3
mm (sample F), 0.4 mm (sample G), 0.5 mm
An optical semiconductor device using five (ten each) holding members 3c of (sample H), 0.6 mm (sample I) and 0.7 mm (sample J) was prepared. The airtightness of these optical semiconductor devices was evaluated by a He leak test (MIL-STD-883). As a result, Samples H to J had no poor airtightness. Sample F had poor airtightness in 2 out of 10 samples. In sample G, airtight failure occurred in one out of ten samples. The present invention is not limited to the above-described embodiments and examples, and various changes may be made without departing from the gist of the present invention. According to the optical semiconductor element housing package of the present invention, a substantially disk-shaped translucent member whose outer peripheral portion is joined to the outer end surface of the cylindrical optical fiber fixing member on the outer side of the frame body is held. The member has a ridge between an inner peripheral surface of the cylindrical portion and a main surface outside the frame body is a chamfer having an angle of 45 ° or more with respect to the inner peripheral surface of the cylindrical portion, and an outer peripheral surface of the cylindrical portion. And the distance between the inner peripheral surface of the optical fiber fixing member is 0.5 mm or more, and the antireflection film can be reliably formed with an effective diameter capable of transmitting a sufficient amount of light to the surface of the light transmitting member. When the translucent member is joined to the holding member with low-melting glass and then the outer peripheral portion of the holding member is joined to the end surface of the fixing member with low-melting brazing material, the translucent member may come off due to stress. The problem that airtightness in the semiconductor package is broken can be solved. Also, the stress applied to the light-transmissive member causes the light-transmissive member to be distorted, causing birefringence or a refractive index distribution to occur in the light-transmissive member, changing the focal point, etc., and deteriorating the optical characteristics. By suppressing this, the transmission characteristics of the light oscillated from the optical semiconductor element in the optical fiber and the airtightness inside the optical semiconductor package can be improved. As a result, it is possible to provide an optical semiconductor element housing package that can operate the optical semiconductor element 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 a sectional view of an example of a conventional package for housing an optical semiconductor element. FIG. 3 is a partially enlarged cross-sectional view showing an optical fiber fixing member and a holding member in the optical semiconductor element housing package of FIG. [Description of Signs] 1: Base 1a: mounting portion 2: frame 2a: through hole 3: optical fiber fixing member 3a: translucent member 3b: end surface 3c: holding member 5: optical semiconductor element

Claims (1)

Claims: 1. A base having a mounting portion on which an optical semiconductor element is mounted on an upper surface, and a through hole on a side portion, and the mounting portion is surrounded on the upper surface of the base. And a cylindrical optical fiber fixing member fitted into the through hole, and an outer peripheral portion joined to an end surface of the optical fiber fixing member on the outer side of the frame, and a central portion of the optical fiber fixing member. A holding member of a substantially disk-shaped light-transmitting member having a cylindrical portion protruding inside the frame body, and a spherical light-transmitting member joined to the inner peripheral surface of the cylindrical portion of the holding member. In the optical semiconductor element housing package provided, the holding member has a ridge between an inner peripheral surface of the cylindrical portion and a main surface outside the frame body at an angle of 45 ° or more with respect to an inner peripheral surface of the cylindrical portion. It is a chamfer of
And a distance between the outer peripheral surface of the cylindrical portion and the inner peripheral surface of the optical fiber fixing member is 0.5 mm or more.