JP2023148890A - Lid and manufacturing method for the same, and optical semiconductor - Google Patents

Abstract

To provide a lid and a manufacturing method for the same that can reduce costs of materials and can reduce complexity when encapsulating a light-emitting element and to provide an optical semiconductor.SOLUTION: A lid 10 for an optical semiconductor includes a base material 11 that is configured of quartz or glass, a Cr/Ni or Ti/Cu stacked film 12 formed in a ring shape on the surface of the base material 11 along an edge portion of a surface of the base material 11 to be bonded to a base part for the optical semiconductor, and a sealing member 13 welded on a Ni or Cu layer that is an upper layer of the stacked film 12. The sealing member 13 is welded on the surface of the Ni or Cu layer of the stacked film 12 in a reducing atmosphere. An optical semiconductor 50 includes a base 30 on which a light-emitting element 20 is mounted and the lid 10 connected to the base 30 and used to encapsulate the light-emitting element 20.SELECTED DRAWING: Figure 2

Description

The present invention relates to a lid that can reduce material costs and complexity during sealing, a manufacturing method thereof, and an optical semiconductor.

As a type of optical semiconductor, research into light-emitting diodes, which have the potential to replace mercury lamps and can output deep ultraviolet light, has become active in recent years. In optical semiconductors, a light emitting element is mounted in a space within a package, and a sealing structure is provided in the package to protect the light emitting element. These packages are composed of a base for mounting a light emitting element and a lid for sealing the light emitting element. One method of sealing the base and the lid is to use a sealing member, such as a brazing material.

For example, Patent Document 1 discloses a package for an optical semiconductor having a sealed structure including a package substrate (base), a window member (lid), and a metal bonding material (brazing material). In this package substrate and window member, a metal layer is provided in the region to be bonded in order to be welded to the metal bonding material, and the metal layer provided on the window member is made of titanium (Ti), platinum (Pt), It is a multilayer film in which gold (Au) is sequentially laminated. Note that it is said that chromium (Cr) may be used instead of titanium, and copper (Cu) and nickel may be used instead of platinum (paragraphs 0032 to 0035 of Patent Document 1).
Furthermore, it is stated that the metal bonding material is a gold-tin preform with a shape corresponding to the area to be bonded, and that the metal bonding material may be temporarily fixed to the base side or the lid side in advance ( Paragraph 0041 of Patent Document 1).

JP2018-37581

In the case of the prior art, there is a problem in that the material cost increases because Au is used in the metal layer for welding the brazing material to the lid. In recent years, the price of Au has soared, and it is important to reduce the amount of Au used in order to reduce costs. Also, it is stated that the metal bonding material may be temporarily fixed to the base side or the lid side, but it is better to weld the brazing material to the lid in advance than to not. When sealing the element, only two elements, the lid and the base, need to be aligned, so the complexity at the time of sealing can be reduced.
This invention has been made in view of these points, and therefore, the purpose of this application is to provide a novel structure that can reduce material costs and reduce complexity during sealing. An object of the present invention is to provide a lid, a method for manufacturing the same, and an optical semiconductor.

In order to achieve this object, according to the lid invention of this application, a base material made of crystal or glass, and a It is characterized by comprising a Cr/Ni or Ti/Cu laminated film formed on the surface of a base material, and a sealing member welded to the Ni layer or Cu layer that is the upper layer of the laminated film. shall be.

Further, according to the invention of the optical semiconductor of this application, the base material is made of crystal or glass, and the base material is attached along the edge of the surface of the base material that is to be joined to the base for the optical semiconductor. a lid comprising a Cr/Ni or Ti/Cu laminated film formed on the surface of the laminated film and a sealing member welded to the Ni layer or Cu layer that is the upper layer of the laminated film; The light emitting device is characterized by comprising the base connected via a stopper member, and a light emitting element mounted in a container formed by the lid and the base.

Further, in a method for manufacturing a lid which is used by being joined to a base and which includes a base material made of crystal or glass, a sealing member is welded along the edge of the surface that is to be joined to the base. a step of forming a Cr/Ni or Ti/Cu laminated film on the surface of the base material along the edge of the surface of the base material that is to be joined to the base; and an upper layer of the laminated film. a step of welding the sealing member on the surface of the Ni layer or Cu layer in a reducing atmosphere.

According to the lid of the present invention, there is no need to provide an Au layer on the surface of the Ni layer or Cu layer that is the upper layer of the Cr/Ni or Ti/Cu laminated film formed on the base material, so material costs can be reduced. be able to. In addition, by welding the sealing member to the lid in advance, when sealing the electronic components mounted on the base, only two elements, the base and the lid, need to be aligned, reducing the complexity of sealing. can be reduced.
According to the optical semiconductor of the present invention, a lid for sealing a light emitting element includes a base material, a Cr/Ni or Ti/Cu laminated film formed on the base material, and an upper layer of this laminated film. Since a lid including a sealing member welded to the sealing member, that is, a lid without an Au layer is used, material costs can be suppressed.
Further, according to the lid manufacturing method, a Cr/Ni or Ti/Cu laminated film is formed on the surface of the base material, and the upper Ni layer or Cu layer of the laminated film is sealed in a reducing atmosphere. Since the step of welding the sealing member is used, the oxide film on the surface of the Ni layer or the Cu layer is removed under a reducing atmosphere, making it possible to weld the sealing member to the Ni layer or the Cu layer. Become. Therefore, it is not necessary to provide an Au layer on the Ni layer or the Cu layer, and it is possible to manufacture a lid in which the sealing member is welded to the Ni layer or the Cu layer.

FIG. 1A is a perspective view showing an outline of a lid according to an embodiment of the present invention. FIG. 1B is a sectional view showing an outline of a lid according to an embodiment of the present invention. FIG. 2A is a perspective view showing an outline of an optical semiconductor according to an embodiment of the present invention. FIG. 2B is a cross-sectional view schematically showing an optical semiconductor according to an embodiment of the present invention. FIG. 2 is an explanatory diagram illustrating an embodiment of the lid manufacturing method of the present invention. FIG. 4 is an explanatory diagram of a manufacturing method example following FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the lid, its manufacturing method, and optical semiconductor of this application will be described with reference to the drawings.
Note that the drawings used in the explanation are merely shown schematically to the extent that these inventions can be understood. Moreover, in each figure used for explanation, the same number is attached|subjected and shown about the same component, and the explanation may be abbreviate|omitted. Furthermore, the shapes, materials, etc. described in the following description are merely preferred examples within the scope of the present invention. Therefore, the present invention is not limited only to the following embodiments.

1. Structure of Lid FIG. 1A is a perspective view showing an outline of a lid according to an embodiment of the present invention. 1B is a cross-sectional view taken along the line AA in FIG. 1A.
The lid 10 of the present invention includes a base material 11 made of crystal or glass and having a rectangular shape in plan view, and a surface of the base material 11 that is to be bonded to, for example, a base for an optical semiconductor. It is formed in a ring shape on the surface of the base material 11 along the edge of the base material, and the base material is bonded to the Cr/Ni or Ti/Cu laminated film 12 and the base for the optical semiconductor from the base material side. Therefore, the sealing member 13 is welded to the Ni layer or Cu layer which is the upper layer of the laminated film 12.
Here, when using the lid of the present invention as a lid for an optical semiconductor that emits ultraviolet light such as UVA, UVB, and UBC, quartz is preferable because it has excellent transmittance to deep ultraviolet light. Furthermore, when glass is used as the base material of the lid, and when the lid is used as a lid for an optical semiconductor that emits deep ultraviolet light such as UVA, UVB, and UBC, the glass has a low transmittance for deep ultraviolet light. High-quality materials such as borosilicate glass and quartz glass are preferred.

According to the lid 10 of the present invention, there is no need to provide an Au layer on the surface of the Ni layer or Cu layer that is the upper layer of the Cr/Ni or Ti/Cu laminated film 12 formed on the base material, so the material cost is reduced. can be suppressed. Moreover, since the sealing member is welded to the lid in advance, when sealing the light emitting element mounted on the base, only two elements, the base and the lid, need to be aligned, reducing the complexity of sealing. can be reduced.

Further, the sealing member 13 is preferably selected from materials that have excellent corrosion resistance and also take heat resistance requirements into consideration. In other words, it has a higher melting point than the solder (melting point: 180°C to 230°C) used when mounting electronic components, such as optical semiconductors, on various electronic devices, which are completed using this lid. It is preferable to select a material that can maintain the airtightness of the package without being remelted, such as AuSn (melting point 280° C. to 300° C.).

2. Structure of Optical Semiconductor The lid of the present invention can be used as a lid material that is a component of an optical semiconductor package. Hereinafter, an example of an optical semiconductor in which the lid of the present invention is used as a lid material of an optical semiconductor package will be explained. FIG. 2 is a diagram for explaining the same, and FIG. 2A shows a base for mounting a light emitting element, a light emitting element mounted on the base, and a lid of the present invention for sealing the light emitting element. , is a perspective view of an optical semiconductor using . Further, (B) is a cross-sectional view of the optical semiconductor taken along line BB in (A). However, both figures (A) and (B) are perspective views or cross-sectional views in an exploded state.

A lid 10 of the present invention, a light emitting element 20 having an arbitrary shape, in this example a rectangular shape in plan view, and a base 30 made of well-known AlN, for example, are prepared. The base 30 in this case has a rectangular shape in plan view, and as shown in FIGS. It includes a bank portion 30b, wiring terminals 30c and 30d connected to the light emitting element provided on the bottom surface of the recessed portion 30a, and a mounting terminal 30e provided on the back surface of the base 30. The wiring terminal 30c and the wiring terminal 30d are electrically connected to the mounting terminal 30e by via wiring (not shown). Further, a metallized film (not shown) corresponding to the sealing member of the lid 10 is provided on the top surface of the bank portion 30b.
Here, the base made of AlN has high thermal conductivity, and because excessive heat causes various problems regarding the performance and reliability of optical semiconductors, it is often used in optical semiconductors to remove as much heat as possible.

The light emitting element 20 is fixed onto the wiring terminal 30c using, for example, a conductive adhesive (not shown), and then the light emitting element 20 and the wiring terminal 30d are connected using, for example, a gold wire 40 using a well-known wire bonding technique. . Next, in order to protect the light emitting element 20 and the gold wire 40, the recess 30a is filled with a sealing resin and hardened. Next, the lid 10 according to the present invention is stacked on the base 30, and a predetermined amount of heat is applied thereto to melt the sealing member of the lid 10, thereby joining the lid 10 and the base 30. In this way, an optical semiconductor 50 having a structure in which the light emitting element 20 is housed in the lid 10 and the base 30 is obtained.

3. Lid Manufacturing Method FIG. 3 is an explanatory diagram illustrating an embodiment of the lid manufacturing method of the present invention. First, a base material 61 made of crystal or glass and having a rectangular shape in plan view, for example, is prepared. Next, a Cr/Ni or Ti/Cu laminated film 62 is formed on the surface of the base material 61 that is to be bonded to the base for an optical semiconductor by a well-known sputtering technique. Next, the laminated film 62 is patterned by photolithography or the like so that it has a ring shape along the edge of the surface that is to be bonded to the base.

Next, the base material 61 on which the laminated film 62 is formed is transported to a processing chamber 70 as shown in FIG. After the base material 61 is transported to the processing chamber 70, a reducing gas is injected into the processing chamber 70 to bring the atmosphere of the processing chamber 70 into a reducing atmosphere state. After the atmosphere in the processing chamber 70 becomes a reducing atmosphere state, a sealing material is preformed in the shape of the region to be joined between the base and the substrate 61 along the edge of the base material 61 in the processing chamber 70. The member 64 is superimposed on the laminated film 62 formed on the base material 61.
Here, the reason for setting the reducing atmosphere is as follows. Normally, the Ni or Cu layer that is the upper layer of the laminated film 62 forms an oxide film on the surface, and since the oxide film has low wettability, the sealing member 63 cannot be welded to the base material 61. By placing the material 61 in a reducing atmosphere, the oxide film on the surface of the Ni or Cu layer can be removed. Thereby, the sealing member 63 can be welded to the base material 61.

Here, examples of the reducing gas used include hydrogen or formic acid. Further, the concentration of the reducing gas is preferably 5 vol % or less in terms of volume ratio, considering the risk of explosion.

Next, the temperature of the reducing gas atmosphere in the processing chamber 70 is increased until it reaches the melting point of the sealing member 63. Thereby, the sealing member 63 is melted and welded to the base material 61. At this time, the temperature of the reducing gas atmosphere needs to be raised to the melting point to melt the sealing member 63, and then lowered steeply. This is because if the temperature continues to rise, the sealing member 63 will continue to melt and the preformed shape will collapse.
In this way, by welding the sealing member 63 in a reducing gas atmosphere, there is no need to provide an Au layer, and since the sealing member is already welded, it is easy to align when sealing the light emitting element. It is possible to obtain a lid that can reduce the complexity of the process.

Here, assuming that AuSn is used for the sealing member, the temperature of the reducing gas atmosphere is preferably 280° C. to 300° C., which is the melting point of AuSn.

In addition, in the above embodiment, an example was described in which a base material having a rectangular shape in a plan view is used to form an optical semiconductor that is rectangular in a plan view. Any shape can be selected depending on the purpose, such as a circular shape. Furthermore, in the above embodiments, the lid of the present invention was used as a lid material that is a component of an optical semiconductor package, but the lid of the present invention is not limited to optical semiconductors, and may be used for packages of other electronic devices. good.

10: Lid of embodiment of the present invention 11: Base material 12: Laminated film 13: Sealing member 20: Light emitting element 30: Base 30a: Recessed portion 30b: Bank portions 30c, 30d: Wiring terminal 30e: Mounting terminal 40: Gold Line 50: Optical semiconductor according to the embodiment of the present invention 60: Lid according to the embodiment of the present invention 61: Base material 62: Laminated film 63: Sealing member 70: Processing chamber

Claims (6)

In a lid that uses a base material made of crystal or glass and is used by being joined to a base,
A laminated film of Cr/Ni or Ti/Cu formed on the surface of the base material along the edge of the surface of the base material that is scheduled to be joined to the base;
a sealing member welded to the Ni layer or Cu layer that is the upper layer of the laminated film;
A lid characterized by comprising. The lid according to claim 1, wherein the sealing member is made of AuSn. A base material made of crystal or glass, a Cr/Ni or Ti/ a lid comprising a Cu laminated film and a sealing member welded to the Ni layer or Cu layer that is the upper layer of the laminated film;
the base connected to the lid via the sealing member;
a light emitting element mounted in a container formed by the lid and the base;
An optical semiconductor comprising: In a method for manufacturing a lid that is used by being joined to a base, the lid includes a base material made of crystal or glass,
When welding a sealing member along the edge of the surface of the base material that is scheduled to be joined to the base,
forming a Cr/Ni or Ti/Cu laminated film on the surface of the base material along the edge of the surface of the base material that is to be joined to the base;
Welding the sealing member to the Ni layer or Cu layer that is the upper layer of the laminated film in a reducing atmosphere;
A method for producing a lid, comprising: 5. The method of manufacturing a lid according to claim 4, wherein the reducing atmosphere is a reducing gas atmosphere of hydrogen or formic acid. 6. The method for manufacturing a lid according to claim 4, wherein the reducing gas atmosphere has a reducing agent concentration of 5 vol% or less in terms of volume ratio.

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