JP5786202B2 - Semiconductor module and manufacturing method thereof - Google Patents

Description

  The present invention relates to a light emitting diode (LED) module as a semiconductor module, for example, an optical semiconductor module, and a manufacturing method thereof.

  A conventional method for manufacturing an optical semiconductor module will be described with reference to FIGS. 7, 8, 9, and 10.

  First, referring to the substrate, lead terminal and cavity wall assembly process of FIG. 7A, lead terminals 2-1 and 2 made of, for example, copper or the like are formed on the upper, lower and side surfaces of the substrate 1 made of epoxy resin or the like. -2 is formed by electrolytic plating or electroless plating. Next, a frame-like cavity wall 3 is mounted around the upper surface of the substrate 1 using an adhesive (not shown) or the like.

  Next, referring to the light emitting element main fixing step in FIG. 7B, an adhesive 6 mainly composed of epoxy or silicone is applied to a position where the light emitting element 5 on the upper surface of the assembled substrate 1 is fixed. . Next, the light emitting element 5 is permanently fixed to the position of the adhesive 6 on the substrate 1 using the collet 7. In the light emitting element main fixing step of FIG. 7B, other pressing means may be used instead of suction fixing the substrate 1 to the vacuum stage 4. Further, instead of the adhesive 6, solder such as gold or silver can be used.

  Next, referring to the adhesive curing step of FIG. 8A, the substrate 1 on which the light emitting element 5 is permanently fixed is transferred to a heating furnace (not shown) and heated to cure the adhesive 6. At this time, the organic gas is evaporated from the adhesive 6, and the contaminant layer 6 a adheres to the substrate 1, the lead terminals 2-1 and 2-2, the light emitting element 5, particularly the pad (conductive part). In the case where solder is used instead of the adhesive 6, a contaminant layer due to the flux adheres similarly.

  Next, referring to the surface cleaning step in FIG. 8B, a contaminant layer adhered on the substrate 1, the lead terminals 2-1, 2-2, the light emitting element 5 and the like prior to the wire bonding step described later. Surface cleaning for removing 6a, for example, plasma cleaning, is performed to prevent a decrease in bonding strength or non-bonding of a bonding wire described later. That is, the optical semiconductor module shown in FIG. 8A is carried into a holder 802 in a vacuum chamber 801 of a plasma etching apparatus, and after evacuation by a vacuum pump 803, a plasma generating gas such as argon gas is supplied and a high frequency power source is supplied. Turn on 804. Reference numeral 805 denotes a ground electrode. As a result, the contaminant layer 6a can be removed by argon plasma. For the plasma cleaning process, see Patent Document 1. Note that ultraviolet cleaning may be performed instead of plasma cleaning.

  Next, referring to the wire bonding step of FIG. 9A, pads of the light emitting element 5, such as the p-side pad 5a and the n-side pad 5b, are connected to the lead terminal 2 by bonding wires (feeding wires) 8-1 and 8-2. Bonded to −1 and 2-2. At this time, in the surface cleaning process, the contaminant layer 6a has already been removed from the surfaces of the substrate 1, the p-side pad 5a and the n-side pad 5b of the light emitting element 5, and the lead terminals 2-1 and 2-2. The wires 8-1 and 8-2 are bonded well.

  Next, referring to the resin sealing step in FIG. 9B, epoxy resin or the like is injected and cured, and the resin layer 9 is sealed. When it is necessary to emit white light, the resin layer 9 may contain a phosphor such as yttrium, aluminum, garnet (YAG) oxide.

  Finally, referring to FIG. 10, the optical semiconductor module 30 is completed. In the optical semiconductor module 30, the bottom surface of the light emitting element 5 is in contact with the substrate 1 through the adhesive 6.

JP-A-11-307819

  However, in the above-described conventional method of manufacturing an optical semiconductor module, the adhesive 6 or solder is used in the light emitting element main fixing step, and the contaminant layer 6a is attached in the adhesive or solder curing step. There is a problem that a cleaning process is required, resulting in an increase in manufacturing cost. Further, there is a problem that the surface cleaning process causes discoloration or deterioration of each component including the substrate 1 and the cavity wall 3. Furthermore, strong cleaning may not be performed until the contaminant layer 6a is removed. In particular, when plasma cleaning is used, the light emitting element 5 may be fatally destroyed.

In order to solve the above-described problems, an optical semiconductor module manufacturing method according to the present invention has a plurality of vent holes over a predetermined area including a semiconductor element mounting area and a peripheral area outside the semiconductor element mounting area. In the state where the step of preparing the substrate, the semiconductor element temporary fixing step of sucking and temporarily fixing the semiconductor element to the semiconductor element mounting area of the substrate by sucking from the back side of the vent hole, and the semiconductor element temporarily fixed to the substrate, A wire bonding step of bonding a power supply wire between the semiconductor element and a conductive portion provided on the substrate, and in a state where the semiconductor element is temporarily fixed to the substrate, the semiconductor element and the power supply wire are sealed with a covering member, comprising a sealing and semiconductor device the present fixing step of the fixing of the semiconductor element and the substrate with a sealing, in the sealing and the semiconductor element present fixing step, the upper surface side opening there of the covering member surrounding region It is intended to be filled in a portion of the upper vent.

A semiconductor module according to the present invention is formed on a substrate having a plurality of vent holes formed over a predetermined region including a semiconductor element mounting region and a peripheral region outside the semiconductor element mounting region. A semiconductor element mounted on the semiconductor element mounting region; a semiconductor element disposed on the semiconductor element mounting region; a power supply wire connecting the semiconductor element and the conductive part; and a sealing layer covering the semiconductor element and the power supply wire. In the region, the substrate and the bottom surface of the semiconductor element are in direct contact with each other, and the sealing layer fills a part of the upper portion of the vent hole having the opening on the upper surface side of the surrounding region.

  According to the present invention, since there is no conventional adhesive layer or solder curing step and contamination surface cleaning step, the manufacturing cost can be reduced, and the discoloration and deterioration of each component and the destruction of the light emitting element are eliminated. .

It is sectional drawing for demonstrating 1st Embodiment of the manufacturing method of the optical semiconductor module which concerns on this invention. It is sectional drawing for demonstrating 1st Embodiment of the manufacturing method of the optical semiconductor module which concerns on this invention. The optical semiconductor module manufactured by the manufacturing method of the optical semiconductor module shown in FIG. 1, FIG. 2 is shown, (A) is a top view, (B) is the BB sectional drawing of (A). It is sectional drawing for demonstrating 2nd Embodiment of the manufacturing method of the optical semiconductor module which concerns on this invention. It is sectional drawing for demonstrating 2nd Embodiment of the manufacturing method of the optical semiconductor module which concerns on this invention. The optical semiconductor module manufactured by the manufacturing method of the optical semiconductor module shown to FIG. 4, FIG. 5 is shown, (A) is a top view, (B) is the BB sectional drawing of (A). It is sectional drawing for demonstrating the manufacturing method of the conventional optical semiconductor module. It is sectional drawing for demonstrating the manufacturing method of the conventional optical semiconductor module. It is sectional drawing for demonstrating the manufacturing method of the conventional optical semiconductor module. The optical semiconductor module manufactured by the manufacturing method of the optical semiconductor module shown in FIG.7, FIG.8, FIG.9 is shown, (A) is a top view, (B) is the BB sectional drawing of (A).

  A first embodiment of a method for manufacturing an optical semiconductor module according to the present invention will be described with reference to FIGS.

  First, referring to the substrate, lead terminal, and cavity wall assembly process of FIG. 1A, the upper surface, the lower surface, and the side surface of the porous substrate 1 ′ made of porous alumina or the like having a vent hole 1′a, for example, Lead terminals 2-1 and 2-2 made of copper or the like are formed by an electrolytic plating method or an electroless plating method. The vent hole 1'a is a through hole formed continuously from the front surface to the back surface of the porous substrate 1 '. Next, a frame-like cavity wall 3 is mounted around the upper surface of the porous substrate 1 ′ using an adhesive (not shown) or the like. In the first embodiment, the porous substrate 1 ′ in which the vent hole 1 ′ a is formed over the entire substrate is used, but the vent hole 1 ′ a is scheduled to mount at least a light emitting element 5 described later. This region (hereinafter referred to as the light emitting element mounting region), that is, at least directly below the light emitting element 5, can be used, and therefore, an air hole partially formed on the substrate can be used. In addition, in the resin sealing and light emitting element main fixing step, which will be described later, in order to prevent the resin from flowing into the vent hole 1'a below the light emitting element before being cured and the suction of the light emitting element 5 is not inhibited, It is preferable that the vent hole having the upper surface side opening in the light emitting element mounting region and the vent hole having the upper surface side opening outside the light emitting element mounting region are independent, and in particular, at least the through hole directly below the light emitting element 5 is provided. The pores 1′a are preferably perpendicular to the upper surface of the porous substrate 1 ′.

  Next, referring to the light emitting element temporary fixing step in FIG. 1B, the assembled porous substrate 1 ′ is placed on the vacuum stage 4, and the porous substrate 1 ′ is placed by a vacuum pump (not shown). Suction and fix from the back side. Next, the light emitting element 5 is placed on the upper surface of the porous substrate 1 ′ using the collet 7. As a result, the light emitting element 5 is sucked through the vent hole 1'a of the porous substrate 1 ', adsorbed to the porous substrate 1', and temporarily fixed.

  Next, referring to the wire bonding step in FIG. 2A, the pads of the light emitting element 5, such as the p-side pad 5a and the n-side pad 5b, are bonded while the light emitting element 5 is temporarily fixed to the porous substrate 1 ′. The lead terminals 2-1 and 2-2 are joined by wires 8-1 and 8-2. At this time, the surfaces of the porous substrate 1 ′, the p-side pad 5 a and the n-side pad 5 b of the light emitting element 5, and the lead terminals 2-1 and 2-2 are not contaminated. Are well bonded. Therefore, since the adhesive 6 or solder used in the conventional light emitting element main fixing process is not used, the p-side pad 5a and the n-side pad 5b of the light-emitting element 5 by the adhesive 6 or solder, and the lead terminal 2-1. , 2-2 is not contaminated. As a result, the conventional heat curing step and surface cleaning step of the adhesive or solder become unnecessary.

  Next, referring to the resin sealing and light emitting element main fixing step in FIG. 2B, the resin layer is injected and cured while temporarily fixing the light emitting element 5 to the porous substrate 1 ′. Seal with 9. At this time, the resin constituting the resin layer 9 is heated and cured by a heater (not shown) provided in the vacuum stage 4. In addition, since temporary fixing by suction continues even during resin sealing, the resin to be injected to form the resin layer 9 is made of a high viscosity or a filler, thereby preventing permeation of the back surface of the substrate 1 '. The injected resin is also filled in the upper part of the vent hole 1'a, but the viscosity is preferably adjusted so as not to go around to the back surface of the porous substrate 1 '. As a result, the light emitting element 5 is permanently fixed to the porous substrate 1 ′ by the resin layer 9. The injected resin is not filled in the vent hole having the upper surface side opening in the light emitting element mounting region, but is filled in a part of the upper portion of the vent hole having the upper surface side opening outside the light emitting element mounting region. Extends to a part of the upper part of the vent hole having an opening on the upper surface side outside the light emitting element mounting region. Thus, when the vent hole 1′a having the upper surface side opening is formed outside the light emitting element mounting region, the resin layer 9 and the porous substrate 1 are filled by filling the vent hole 1′a with resin. The bonding strength between the light emitting element 5 and the bonding strength between the light emitting element 5 and the porous substrate 1 can be increased. When it is necessary to emit white light, the resin layer 9 can contain a phosphor such as yttrium / aluminum / garnet (YAG) oxide.

  Finally, referring to FIG. 3, when the suction operation by the vacuum pump (not shown) is stopped and the optical semiconductor module shown in FIG. 2B is taken out from the vacuum stage 4, the optical semiconductor module 10 is completed. In the optical semiconductor module 10, the light emitting element 5 is fixed to the porous substrate 1 ′ with a sealing resin, and the bottom surface of the light emitting element 5 is not formed with an adhesive or solder as in the prior art, and the porous substrate 1 ′. Is in direct contact. In addition, in the vent hole 1 ′ a of the porous substrate 1 ′, the upper part of the vent hole 1 ′ a existing outside the light emitting element mounting region is filled with a part of the resin layer 9.

  Thus, according to the first embodiment described above, the bonding wires 8-1 and 8-2 are applied while the light emitting element 5 is temporarily fixed to the porous substrate 1 ′ by suction, thereby making the light emitting element 5 porous. Since the main substrate 1 'is permanently fixed by resin sealing, the curing process of the adhesive or solder and the surface cleaning process of the contaminant layer by the conventional method are unnecessary, and as a result, the manufacturing cost can be reduced. In addition, there is no discoloration or deterioration of each constituent member due to the surface cleaning process, and there is no destruction of the light emitting element 5.

  A second embodiment of the method for manufacturing an optical semiconductor module according to the present invention will be described with reference to FIGS.

  First, referring to the substrate, lead terminal, and cavity wall assembly process of FIG. 4A, leads made of, for example, copper or the like on the upper surface, the lower surface, and the side surface of the substrate 1A having the circular holes (open holes) 1A-0. The terminals 2-1 and 2-2 are formed by electrolytic plating or electroless plating. Next, a frame-like cavity wall 3 is mounted around the upper surface of the substrate 1A using an adhesive (not shown) or the like.

  Next, referring to the light-emitting element temporary fixing step in FIG. 4B, the assembled substrate 1A is placed on the vacuum stage 4 and is made of porous alumina or the like having a vent hole 1B-0. 1B is sucked from the back surface of the porous substrate 1B by a vacuum pump (not shown) and temporarily fixed. In this case, the porous substrate 1B is larger than the circular hole 1A-0 of the substrate 1A. Next, the light emitting element 5 is placed on the upper surface of the porous substrate 1 </ b> B using the collet 7. As a result, the light emitting element 5 is sucked through the vent hole 1B-0 of the porous substrate 1B, adsorbed to the porous substrate 1B, and temporarily fixed. The porous substrate 1B can be fixed to the substrate 1A in advance with an adhesive. Further, in the resin sealing and light emitting element main fixing step, which will be described later, in order to prevent the resin from flowing into the vent hole 1B-0 below the light emitting element 5 before being cured and the suction of the light emitting element 5 is not hindered. Of these, the vent having the upper surface side opening in the light emitting element mounting region and the vent hole having the upper surface side opening outside the light emitting element mounting region are preferably independent, and in particular, at least directly below the light emitting element 5. The vent hole 1B-0 is preferably perpendicular to the upper surface of the porous substrate 1B.

  Next, referring to the wire bonding step of FIG. 5A, the pads of the light-emitting element 5, such as the p-side pad 5a and the n-side pad 5b, are bonded to the porous substrate 1B while temporarily fixing the light-emitting element 5 to the porous substrate 1B. The lead terminals 2-1 and 2-2 are joined by 8-1, 8-2. At this time, since the surfaces of the porous substrate 1B, the p-side pad 5a and the n-side pad 5b of the light emitting element 5, and the lead terminals 2-1 and 2-2 are not contaminated, the bonding wires 8-1 and 8-2 are Bonded well. Therefore, the adhesive 6 or solder used in the conventional light emitting element main fixing process is not used. As a result, the conventional heat curing step and surface cleaning step of the adhesive or solder become unnecessary.

  Next, referring to the resin sealing and light emitting element main fixing step in FIG. 5B, the resin layer 9 is cured by injecting a silicone resin and the like while temporarily fixing the light emitting element 5 to the porous substrate 1B. Seal with. At this time, the resin layer 9 is heated and cured by a heater (not shown) provided in the vacuum stage 4. In addition, since temporary fixing by suction continues even during resin sealing, the resin layer 9 is made of high viscosity or filled with filler to suppress permeation to the back surface of the porous substrate 1B. The injected resin is also filled in the upper part of the vent hole 1B-0, but the viscosity is preferably adjusted so as not to go around to the back surface of the substrate 1A. As a result, the light emitting element 5 is permanently fixed to the porous substrate 1 </ b> B by the resin layer 9. The injected resin is not filled in the vent hole having the upper surface side opening in the light emitting element mounting region, but is filled in a part of the upper portion of the vent hole having the upper surface side opening outside the light emitting element mounting region. Extends to a part of the upper part of the vent hole having an opening on the upper surface side outside the light emitting element mounting region. Thus, when the vent hole 1B-0 having the upper surface side opening is formed outside the light emitting element mounting region, the resin layer 9 and the porous substrate 1B are filled by filling the vent hole 1B-0 with resin. The bonding strength between the light-emitting element 5 and the porous substrate 1B can be increased. In this case as well, when it is necessary to emit white light, the resin layer 9 can contain a phosphor such as yttrium, aluminum, garnet (YAG) oxide. Also in the second embodiment, resin is used as a covering member for sealing the substrate 1A, the porous substrate 1B, the bonding wires 8-1, 8-2, and the light emitting element 5. It is not limited to resin, and other translucent members such as glass can be used.

  Finally, referring to FIG. 6, when the suction operation by the vacuum pump (not shown) is stopped and the optical semiconductor module shown in FIG. 5B is taken out from the vacuum stage 4, the optical semiconductor module 20 is completed. In the optical semiconductor module 20, the light emitting element 5 is fixed to the porous substrate 1B with a sealing resin, the porous substrate 1B is fixed to the substrate 1A with a sealing resin, and the bottom surface of the light emitting element 5 is the same as the conventional one. In addition, it is in direct contact with the porous substrate 1B without using an adhesive or solder. In addition, in the vent hole 1B-0 of the porous substrate 1B, a part of the resin layer 9 is filled in the upper part of the vent hole 1B-0 existing outside the light emitting element mounting region.

  Thus, also in the above-described second embodiment, the bonding wires 8-1 and 8-2 are applied while temporarily fixing the light-emitting element 5 to the porous substrate 1B by suction, and the light-emitting element 5 is attached to the porous substrate. Since it is permanently fixed to 1B by resin sealing, the curing process of the adhesive or solder and the process of cleaning the surface of the contaminant layer by the conventional method are not required, and as a result, the manufacturing cost can be reduced. Moreover, there is no discoloration and deterioration of the light emitting element 5 by the surface cleaning process. Furthermore, although the circular hole 1A-0 is provided in the substrate 1A, since the large substrate 1A does not have to be porous as much as the porous substrate 1B is provided, the formation of the lead terminals 2-1 and 2-2 is the first. The manufacturing cost can be further reduced by, for example, being easier than on the porous substrate 1 ′ of the embodiment.

  Next, a method for forming the air holes 1'a of the porous substrate 1 'and the air holes 1B-0 of the porous substrate 1B will be described. In addition, in this invention, the formation method of a vent hole is not restricted to the following formation methods.

  As a method for forming the air holes, an alumina sintered body in which alumina particles having a plurality of particle diameters are combined can be used. For example, coarse alumina particles having an average particle diameter of 2 to 5 μm and fine alumina particles having an average particle diameter of 1 μm or less are sufficiently mixed at a predetermined ratio, pressed and molded, and heated at a high temperature, for example, 1700 ° C. and in an air atmosphere. Sinter. As a result, an alumina sintered body having vent holes with a diameter of 2 μm or less is formed as the porous substrate 1 ′ or the porous substrate 1 </ b> B.

  As another method for forming the air holes, the anodized film having a number of depressions is formed by anodizing the surface of the aluminum substrate, the anodized film is partially dissolved using acid or alkali, and the depressions are further anodized. Then, the recess is grown in the depth direction to form a through hole as a vent hole.

  In the case of suction using air, the diameter of the vent hole 1′a of the porous substrate 1 ′ and the vent hole 1B-0 of the porous substrate 1B is preferably several tens nm to several hundred nm, and a light emitting element such as an LED element is used. In the case of suction, the diameter is preferably 0.1 to 0.2 μm depending on the degree of light leakage and the suction force. The flatness and the porosity of the porous substrate 1 ′ and the porous substrate 1 </ b> B are also appropriately selected according to the size of the light emitting element such as the LED element, the suction force, and the required strength.

  In addition, the shapes of the porous substrate 1 ′ and the porous substrate 1 </ b> B described above can be appropriately changed to a circular shape, a rectangular shape, or the like.

  In the first and second embodiments described above, the porous substrate in which the air holes are formed over the entire substrate is used. However, the air holes may be formed at least in the light emitting element mounting region. What was formed partially on the top can be used. In addition, an uneven surface structure (including those penetrating the substrate and those not penetrating the substrate) for improving the adhesive strength with the resin layer can also be formed outside the light emitting element mounting region.

  Further, the first and second embodiments described above relate to the optical semiconductor module, but the present invention can also be applied to semiconductor modules other than the optical semiconductor module. In this case, the light emitting element 5 is a semiconductor element.

  In the above-described first and second embodiments, a resin is used as a covering member for sealing a semiconductor element and the like, and a resin layer is formed as a sealing layer. It is not limited to resin, and other covering members such as glass can be used, and a glass layer or the like can be formed as a sealing layer. The covering member may be a light-transmitting member when the semiconductor element is a light receiving element or a light emitting element.

1: substrate 1 ′: porous substrate 1′a: vent hole 1A: substrate 1A-0: circular hole 1B: porous substrate 1B-0: vent holes 2-1, 2-2: lead terminal 3: cavity wall
4: Vacuum stage
5: Light emitting element 6: Adhesive
6a: Contaminant layer
7: Collet
8-1, 8-2: Bonding wire
9: Resin layer 10, 20, 30: Optical semiconductor module 801: Vacuum chamber 802: Holder 803: Vacuum pump 804: High frequency power source 805: Ground electrode

Claims (5)

Preparing a substrate having a plurality of vent holes over a predetermined area including a semiconductor element mounting area and a peripheral area outside the semiconductor element mounting area ;
A semiconductor element temporary fixing step of sucking and temporarily fixing a semiconductor element to the semiconductor element mounting region of the substrate by sucking from the back surface side of the vent;
A wire bonding step of bonding a power supply wire between the semiconductor element and a conductive portion provided on the substrate in a state where the semiconductor element is temporarily fixed to the substrate;
With the semiconductor element temporarily fixed to the substrate, the semiconductor element and the power supply wire are sealed with a covering member, and the semiconductor element and the substrate are permanently fixed by the sealing. comprising the step,
A method for manufacturing a semiconductor module, wherein, in the sealing and semiconductor element main fixing step, the covering member is filled in a part above an air hole having an opening on the upper surface side of the peripheral region .   The method of manufacturing a semiconductor module according to claim 1, wherein the substrate comprises a porous substrate. The substrate includes a first substrate having an opening, and a second substrate made of a porous substrate disposed on the first substrate and having the vent hole ,
The conductive portion is formed on the first substrate, the semiconductor element mounting region is formed on the second substrate,
The semiconductor element mounting region is disposed on the opening,
2. The method of manufacturing a semiconductor module according to claim 1, wherein, in the semiconductor element temporary fixing step, the semiconductor element is adsorbed by suction from the back surface of the porous substrate through the opening.   4. The method for manufacturing a semiconductor module according to claim 1, wherein at least a vent hole immediately below the semiconductor element among the vent holes of the substrate is substantially perpendicular to the upper surface of the substrate. 5. A substrate having a plurality of vent holes formed over a predetermined region including a semiconductor element mounting region and a peripheral region outside the semiconductor element mounting region ;
A conductive portion formed on the substrate;
A semiconductor element disposed on the semiconductor element mounting region;
A power supply wire connecting the semiconductor element and the conductive portion;
A sealing layer covering the semiconductor element and the power supply wire,
In the semiconductor element mounting region, the substrate and the bottom surface of the semiconductor element are in direct contact,
The semiconductor module is a semiconductor module in which the sealing layer is filled in a part above an air hole having an opening on the upper surface side of the surrounding region .

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