JP2013145838A - Photoelectric conversion element mounting member and photoelectric conversion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photoelectric conversion device which reduces inclination of a mounted photoelectric conversion element.SOLUTION: A photoelectric conversion element mounting member 1 includes: an insulation substrate 11; a first electrode 12 and a second electrode 13 provided on an upper surface of the insulation substrate 11 and on which a photoelectric conversion element 2 is mounted. The first electrode 12 has multiple first mounting regions 12a. The multiple first mounting regions 12a are arranged parallel to each other. The second electrode 13 has second mounting regions 13a. Each second mounting region 13a is disposed between the multiple first mounting regions 12a, extends in an extension direction of the multiple first mounting regions 12a, and has the same width as the multiple first mounting regions 12a. This structure reduces a thickness difference between the first mounting region 12a and the second mounting region 13a and thus reduces the inclination of a mounted photoelectric conversion element 2.

Description

  The present invention relates to a photoelectric conversion element mounting member and a photoelectric conversion device.

  For example, a photoelectric conversion device in which a photoelectric conversion element such as a light emitting element having a plurality of bumps is flip-chip mounted on a photoelectric conversion element mounting member is known. That is, the photoelectric conversion element is electrically connected to the photoelectric conversion element mounting member by bonding the plurality of bumps of the photoelectric conversion element and the plurality of electrodes provided on the photoelectric conversion element mounting member. (For example, see Patent Document 1). The plurality of electrodes have a plurality of mounting areas, and the plurality of mounting areas are arranged in parallel in a plan view.

Japanese Patent Laid-Open No. 5-55635

  However, in the photoelectric conversion device, the thickness of the plurality of electrodes in the photoelectric conversion element mounting member may be different from each other. This is because, for example, when a plurality of electrodes are formed by applying a conductive paste by screen printing to form a conductive pattern and firing the conductive pattern, the thickness of the conductive pattern varies depending on the convenience of screen printing. Was the cause. When the thicknesses of the plurality of electrodes are different from each other, the photoelectric conversion element mounted on the photoelectric conversion element mounting member may be inclined.

  A photoelectric conversion element mounting member according to an aspect of the present invention includes an insulating substrate, and a first electrode and a second electrode that are provided on the upper surface of the insulating substrate and on which the element is mounted. The first electrode has a plurality of first mounting areas. A plurality of first mounting areas are arranged in parallel to each other. The second electrode has a second mounting area. The second mounting region is disposed between the plurality of first mounting regions and extends in the extending direction of the plurality of first mounting regions, and has the same width as the plurality of first mounting regions. Have.

  A photoelectric conversion device according to another aspect of the present invention includes a photoelectric conversion element mounting member having the above-described configuration, and a photoelectric conversion element mounted on the first mounting area and the second mounting area of the photoelectric conversion element mounting member. have.

  In the photoelectric conversion element mounting member according to one aspect of the present invention, the second mounting region is disposed between the plurality of first mounting regions and extends in the extending direction of the plurality of first mounting regions. It extends and has the same width as the plurality of first mounting areas. Therefore, when the first electrode and the second electrode are formed using, for example, a screen printing method, the width of the conductor pattern serving as the first mounting region and the width of the conductor pattern serving as the second mounting region Since the difference in thickness of the printed conductor pattern can be reduced, the difference in thickness between the first mounting area and the second mounting area can be reduced, and the inclination of the mounted photoelectric conversion element can be reduced. Can be reduced.

It is a top view which shows the photoelectric conversion apparatus in the 1st Embodiment of this invention in the state which saw through the photoelectric conversion element. It is a longitudinal cross-sectional view in AA of the electronic device shown by FIG. It is a top view which shows the photoelectric conversion apparatus in the 2nd Embodiment of this invention in the state which saw through the photoelectric conversion element.

  Hereinafter, some exemplary embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
As in the example shown in FIGS. 1 and 2, the photoelectric conversion device according to the first embodiment of the present invention includes a photoelectric conversion element mounting member 1 and a photoelectric conversion mounted on the photoelectric conversion element mounting member 1. Element 2. 1 and 2, the photoelectric conversion device is provided in a virtual xyz space and is placed on the xy plane. In the example shown in FIG. 1, the photoelectric conversion element 2 is indicated by a broken line, and the light emitting device is shown in a state where the photoelectric conversion element 2 is seen through.

  The photoelectric conversion element mounting member 1 is provided on the insulating substrate 11, the upper surface of the insulating substrate 11, the first electrode 12 and the second electrode 13 on which the photoelectric conversion element 2 is mounted, and the insulating substrate 11. A wiring conductor 14 provided in the interior and electrically connected to the first electrode 12 or the second electrode 13 and a lower surface of the insulating substrate 11 and electrically connected to the wiring conductor 14 The external terminal 15 is provided.

  The insulating substrate 11 has an upper surface including the mounting region of the photoelectric conversion element 2 and has a rectangular plate shape in plan view. The insulating substrate 11 has a laminated structure in which a plurality of insulating layers are stacked. The insulating substrate 11 functions as a support for supporting the photoelectric conversion element 2, and the photoelectric conversion element 2 is bonded onto the mounting region at the center of the upper surface via a bonding agent such as a low melting point brazing material or a conductive resin. Fixed.

  The material of the insulating substrate 11 is ceramics such as an aluminum oxide sintered body (alumina ceramic), an aluminum nitride sintered body, a mullite sintered body, and the like.

  If the insulating substrate 11 is, for example, an aluminum oxide sintered body, an appropriate organic binder and solvent are added to and mixed with raw material powders such as aluminum oxide, silicon oxide, magnesium oxide, and calcium oxide to form a mud. None, this is formed into a sheet shape by a conventionally known doctor blade method or calendar roll method to obtain a ceramic green sheet, and then a suitable punching process is performed on the ceramic green sheet, and a plurality of these are laminated, Manufactured by firing at a high temperature (about 1500 ° C to 1600 ° C).

  The first electrode 12 has a plurality of first mounting regions 12a, and the plurality of first mounting regions 12a are arranged in parallel to each other. Such a first electrode 12 is in contact with a first mounting region 12a having a shape extending in the x-axis direction and one end of the plurality of first mounting regions 12a as in the example shown in FIG. And a first joining region having a shape extending in the y-axis direction. The first bonding region electrically connects the plurality of first mounting regions 12a. In the example shown in FIG. 1, the plurality of first mounting regions 12a are provided to have the same width and the same length. In the present embodiment, the width of the first mounting area 12a is the dimension in the y-axis direction of the first mounting area 12a, and the length of the first mounting area 12a is the x of the first mounting area 12a. It is the dimension in the axial direction.

The second electrode 13 has a second mounting region 13a. The second mounting region 13a is disposed between the plurality of first mounting regions 12a and extends in the extending direction of the plurality of first mounting regions 12a, and the plurality of first mounting regions 12a. Have the same width and length. In the present embodiment, the extending direction of the first mounting region 12a refers to the x-axis direction in the example shown in FIG. The width of the second mounting area 13a is the dimension in the y-axis direction of the second mounting area 13a, and the length of the second mounting area 13a is the dimension in the x-axis direction of the first mounting area 13a. is there.

  Similar to the first electrode 12, the second electrode 13 is in contact with one end of the second mounting region 13a having a shape extending in the x-axis direction and a plurality of second mounting regions 13a. And a second joining region having a shape extending in the axial direction. The second bonding region electrically connects the plurality of second mounting regions 13a. Note that “the second mounting region 13a has the same width as the first mounting region 12a” means that in the example shown in FIG. 1, the width D13a of the second mounting region 13a is equal to that of the first mounting region 12a. It means that the width is in the range of 0.8 to 1.2 times the width D12a.

  The material of the first electrode 12 and the second electrode 13 is a metal such as tungsten (W), molybdenum (Mo), manganese (Mn), silver (Ag), copper (Cu).

  For example, a metallized paste for the first electrode 12 and the second electrode 13 is printed on a ceramic green sheet for the insulating substrate 11 by a printing means such as a screen printing method, and the electrode pattern for the first electrode 12 and the second electrode The electrode pattern for the electrode 13 is formed so as to have the same width, and then fired together with the ceramic green sheet for the insulating substrate 11.

  As described above, the electrode pattern for the first electrode 12 and the electrode pattern for the second electrode 13 are formed to have the same width, so that the difference in thickness of the electrode pattern can be reduced. This is because the electrode pattern for the first electrode 12 and the electrode pattern for the second electrode 13 are pasty, and the surface of the electrode pattern is curved due to surface tension. If the electrode pattern has a curved shape, the thickness of the electrode pattern increases as the curvature increases. Further, since the curvature of the surface of the electrode pattern increases as the ratio of the portion not in contact with the ceramic green sheet increases, the curvature increases and the thickness of the electrode pattern increases as the width of the electrode pattern decreases. Therefore, if the widths of the plurality of electrode patterns are the same, the difference in thickness of the electrode patterns can be reduced.

  The metallized paste for the first electrode 12 and the second electrode 13 is made by adding an organic binder, an organic solvent, and, if necessary, a dispersant to one or more of the above metal powders as the main component. Then, it is prepared by mixing and kneading by a kneading means such as a ball mill, a three-roll mill or a planetary mixer.

  The amount of the organic binder used in the metallized paste for the first electrode 12 and the second electrode 13 may be an amount that can be easily decomposed and removed during firing and can disperse the metal powder. It is desirable that the amount be about 5 to 20% by mass relative to the amount. The solvent is preferably 4 to 15% by mass with respect to the metal powder.

  In order to match the firing shrinkage behavior or shrinkage rate of the ceramic green sheet 1 during firing or to ensure the bonding strength between the first electrode 12 and the second electrode 13 after firing, the metallized paste is made of glass. Alternatively, ceramic powder may be added.

  The wiring conductor 14 is provided in the insulating substrate 11 so as to be electrically connected to the external terminal electrode 15 and the first electrode 12 or the second electrode 13. The wiring conductor 14 is for electrically connecting the photoelectric conversion element 2 mounted on the photoelectric conversion element mounting member 1 and an external circuit board.

The wiring conductor 14 includes a planar conductor provided between insulating layers inside the insulating substrate 11, and a penetrating conductor that penetrates the insulating layer constituting the insulating substrate 11 and electrically connects the planar conductors positioned above and below. Contains.

  The wiring conductor 14 is formed by, for example, applying a metallized paste for the wiring conductor 14 to a ceramic green sheet for the insulating substrate 11 by printing means such as a screen printing method, and baking it together with the ceramic green sheet for the insulating substrate 11. The The through conductor is formed, for example, in a ceramic green sheet for the insulating substrate 11 by a die or punching process by punching or laser processing or the like, and through metal for the through conductor is formed in the through hole. The paste is filled by the above printing means and formed by firing together with the ceramic green sheet for the insulating substrate 11.

  The metallized paste may be produced by the same method as the metallized paste for the first electrode 12 and the second electrode 13 described above. The metallized paste for the through conductor is adjusted to have a higher viscosity than the metallized paste for the wiring conductor 14 so as to be suitable for filling by changing the kind or addition amount of the organic binder and the organic solvent.

  The external terminal electrode 15 is a portion joined to the wiring of the external electric circuit board. The external terminal electrode 15 is provided on the lower surface of the insulating substrate 11 joined to the wiring conductor 14 as in the example shown in FIG. The external terminal electrode 15 can be formed by the same material and the same method as the first electrode 12 and the second electrode 13.

On the surfaces of the first electrode 12, the second electrode 13, and the external terminal electrode 15, a metal plating layer having excellent corrosion resistance, such as nickel and gold, is applied to prevent corrosion. Further, when metal plating is applied to the first electrode 12, the second electrode 13, and the external terminal electrode 15, the first electrode 12, the second electrode 13, and the photoelectric conversion element 2 or the external terminal electrode 15 are provided. And the external circuit board can be firmly joined. For example, a nickel plating layer having a thickness of about 1 to 10 μm and a gold plating layer having a thickness of about 0.1 to 3 μm are sequentially deposited on the surfaces of the first electrode 12, the second electrode 13 and the external terminal electrode 15. The

  The photoelectric conversion element 2 is mounted on the upper surface of the photoelectric conversion element mounting member 1 so as to overlap the first mounting area 12a and the second mounting area 13a in plan view. The photoelectric conversion element 2 is, for example, a light emitting element 2a. The photoelectric conversion element 2 includes a first mounting region of the photoelectric conversion element mounting member 1 by a conductive bonding material 21 such as a brazing material made of gold (Au) -silicon (Si) alloy or an epoxy resin containing silver (Ag). It is joined to 12a and the second mounting region 13a by a flip chip mounting method. The conductive bonding material 21 has, for example, a bump shape. The photoelectric conversion element 2 is sealed with a sealing material 4 such as a resin material.

  The photoelectric conversion element mounting member 1 of the present embodiment is provided with an insulating substrate 11 and a first electrode 12 and a second electrode 13 on which the photoelectric conversion element 2 is mounted. Have. The first electrode 12 has a plurality of first mounting regions 12a. A plurality of first mounting regions 12a are arranged in parallel to each other. The second electrode 13 has a second mounting region 13a. The second mounting region 13a is disposed between the plurality of first mounting regions 12a and extends in the extending direction of the plurality of first mounting regions 12a. The plurality of first mounting regions 12a Have the same width. Therefore, when the first electrode 12 and the second electrode 13 are formed using a screen printing method, the width of the conductor pattern that becomes the first mounting region 12a and the conductor pattern that becomes the second mounting region 13a. Since the difference in thickness of the printed conductor pattern can be reduced, the difference in thickness between the first mounting region 12a and the second mounting region 13a can be reduced for mounting. The inclination of the photoelectric conversion element 2 can be reduced.

Further, if the lengths of the plurality of first mounting areas 12a and the plurality of second mounting areas 13a are the same in the extending direction of the plurality of first mounting areas 12a, Second mounting area
This is effective in further reducing the difference in thickness from 13a.

  The photoelectric conversion device of this embodiment includes a photoelectric conversion element mounting member 1 and a photoelectric conversion element 2 mounted on the first mounting region 12a and the second mounting region 13a of the photoelectric conversion element mounting member 1. Since it has, it becomes a photoelectric conversion apparatus with which the inclination of the photoelectric conversion element 2 was reduced. In addition, since the difference in thickness between the first mounting region 12a and the second mounting region 13a is reduced, the difference in thickness of the conductive bonding material 21 is also reduced. Since the region where the thickness of the bonding material 21 is large can be reduced, the bonding strength between the photoelectric conversion element mounting member 1 and the photoelectric conversion element 2 can be improved.

(Second Embodiment)
Next, a photoelectric conversion device according to a second embodiment of the present invention will be described with reference to FIG.

  The photoelectric conversion device according to the second embodiment of the present invention is different from the electronic device according to the first embodiment described above in that the length of the first mounting region 12a and the first mounting region 12a are the same as in the example shown in FIG. The width of one mounting area 12a is the same, and the length of the second mounting area 13a and the width of the second mounting area 13a are the same. Since the length of the first mounting area 12a with respect to the width of the first mounting area 12a is the same as the length of the second mounting area 13a with respect to the width of the second mounting area 13a, the first mounting area The difference in thickness between the first end (for example, the end in the width direction) and the second end (for example, the end in the length direction) in 12a, and the first end in the second mounting region 13a The difference in thickness between the portion (for example, the end portion in the width direction) and the second end portion (for example, the end portion in the length direction) can be more effectively reduced.

  In addition, this invention is not limited to the example of the above-mentioned embodiment, A various change is possible. For example, the photoelectric conversion device may have a structure in which a plurality of heat radiating members are mounted, and the heat radiating members may be provided so as to overlap the photoelectric conversion elements 2 in a plan view. Note that it is preferable that the heat dissipating member has a larger area than the first mounting region 12a and the second mounting region 13a.

  Moreover, when the photoelectric conversion element 2 is a light emitting element, you may have a reflection layer on the upper surface of the member 1 for photoelectric conversion element mounting. For example, the reflective layer is provided between the plurality of first mounting regions 12a and the plurality of second mounting regions 13a so as to extend in the extending direction of the first mounting region 12a. Such a reflective layer may be electrically independent of the first electrode 12 and the second electrode 13, or may be electrically connected to the first electrode 12 or the second electrode 13. Good. When the reflective layer is electrically connected to the first electrode 12 or the second electrode 13, it is possible to improve the heat dissipation of the light emitting element when an underfill is provided below the photoelectric conversion element 2. It is valid.

  Further, a copper plating layer having a thickness of about 10 to 80 μm and a nickel plating layer having a thickness of about 1 to 10 μm may be sequentially deposited between the nickel plating layer and the gold plating layer. By using a copper plating layer, the thermal conductivity of the plating layer can be improved.

1 ... Member for mounting photoelectric conversion element
11 ... Insulating substrate
12 ... 1st electrode
12a: First mounting area
13 ... Second electrode
13a ... Second mounting area
14 ... Wiring conductor
15 ... External terminal electrode 2 ... Photoelectric conversion element
21 ... Conductive bonding material

Claims (3)

An insulating substrate;
Provided on the upper surface of the insulating substrate, comprising a first electrode and a second electrode on which the element is mounted;
The first electrode has a plurality of first mounting areas, and the plurality of first mounting areas are arranged in parallel;
The second electrode has a second mounting region, the second mounting region is disposed between the plurality of first mounting regions, and the plurality of first mounting regions. A photoelectric conversion element mounting member, which extends in a direction in which the photoelectric conversion element extends and has the same width as the plurality of first mounting regions. The lengths of the plurality of first mounting regions in the extending direction of the plurality of first mounting regions;
2. The photoelectric conversion element mounting member according to claim 1, wherein lengths of the plurality of second mounting regions in an extending direction of the plurality of first mounting regions are the same.   A photoelectric conversion element mounting member according to claim 1, and a photoelectric conversion element mounted on the first mounting region and the second mounting region of the photoelectric conversion element mounting member. A featured photoelectric conversion device.

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