JP2005136399A - Semiconductor device mounting method and mounting substrate of semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow joining to be surely, efficiently carried out by reducing the occurrence of a joining failure caused by the application of ultrasonic vibration, in mounting where a semiconductor device is mounted on a substrate by joining substrate electrodes of the substrate and device electrodes of the semiconductor device between them by applying the ultrasonic vibration. <P>SOLUTION: Joining components made of gold nanopaste are located between each of the device electrodes and each of the substrate electrodes, and each of the device electrodes and each of the substrate electrodes are abutted interposing each of the joining components between them. In the abutted state, each of the joining components, each of the substrate electrodes and each of the device electrodes are joined. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a semiconductor element mounting method for producing a semiconductor element mounting substrate by mounting the semiconductor element on the substrate by bonding the substrate electrode of the substrate and the element electrode of the semiconductor element, and the semiconductor element mounting Regarding the substrate.

  Conventionally, LED (LED element) which is an example of such a semiconductor element is used for uses, such as a fluorescent lamp, using the light emission function. However, although an LED can emit light by applying a voltage, heat is generated along with this, and there is a problem that the light emission efficiency of the LED is reduced due to the generation of this heat, and the light emission illuminance is reduced. In order to solve such a problem, various ideas have been devised conventionally for efficiently releasing the heat generated in the LED.

  For example, as one of such contrivances, an LED is bonded to a substrate via a bump, and a technique is used in which heat is released to the substrate via the bump. In this method, in order to increase the contact area (heat transfer area) of the bump, the bump is formed as a plated bump by a plating process suitable for forming a bump having a relatively large size.

  A conventional mounting method for mounting such an LED on a substrate will be described below with reference to the drawings (for example, see Patent Document 1).

  10A and 10B are schematic explanatory views schematically showing the LED mounting method. As shown in FIG. 10A, the LED 501 includes a pad 502 as an example of a plurality of element electrodes formed of aluminum (Al) on the lower surface side in the drawing. The substrate 503 includes a plurality of substrate electrodes 504 formed on the upper surface side of the LED 501 in combination with the arrangement of the respective pads 502 of the LED 501. Further, bumps 505 (hereinafter referred to as bumps 505), which are examples of protruding electrodes formed of gold (Au) by plating, are formed on each substrate electrode 504 of the substrate 503.

  As shown in FIG. 10A, the upper surface of the LED 501 is held by suction with the suction nozzle 510, and the suction nozzle 510 is moved relative to the substrate 503 in the horizontal direction. Position alignment with each bump 505 of the substrate 503 is performed. Thereafter, the suction nozzle 510 is lowered to bring the bumps 505 and the pads 502 into contact with each other.

  Next, as shown in FIG. 10B, ultrasonic vibration is applied to the LED 501 from the suction nozzle 510 while maintaining this contact state. Thereby, metal bonding is performed at the contact portion between each bump 505 and each pad 502, and the LED 501 is mounted on the substrate 503.

  In addition to the case where each bump 505 is formed on each substrate electrode 504 of the substrate 503, the case where each bump 505 is formed on each pad 502 of the LED 501, or each substrate electrode 504 and In some cases, it is formed on both of the pads 502.

Here, a general method of forming the gold bump 505 by the plating method used in the conventional mounting method will be described with reference to the flowchart shown in FIG.
In the flowchart of FIG. 13, a case where the bump 505 is formed on the semiconductor element side will be described.

  First, in step S1 in the flowchart of FIG. 13, a wafer to be a semiconductor element (for example, LED) is received. Thereafter, in step S2, a plating common electrode film (UBM) is performed, for example, by sputtering on the surface of the wafer where the element electrodes are formed. Thereafter, in step S3, a plating resist film is formed on the surface of the UBM while patterning a plating bump mold.

  Thereafter, in step S4, gold bumps are formed by electrolytic plating using the plating resist film. Thereafter, in step S5, the plating resist film existing around the formed gold bump is peeled off, and the plating resist film is removed. Thereafter, in step S6, the UBM is etched to reduce the thickness of the UBM. Finally, in step S7, the formed gold bumps are inspected to complete the gold bump forming process.

JP 2000-68327 A

  However, in such a semiconductor element mounting method, as described above, the bump 505 formed on the LED 501 by the plating method has a large size, and accordingly, each bump 505 and each substrate electrode 504. Since the contact area at the time of contact with the above also increases, there may be cases where sufficient vibration for bonding cannot be applied by ultrasonic vibration, or the additional time of ultrasonic vibration for bonding becomes long. Can occur. In such a case, there is a problem that it may be difficult to reliably join the LED 501 and the substrate 503. Such a problem occurs not only when each bump 501 is formed on the LED 501 side, but also when the bump 501 is formed on the substrate 503 side as shown in FIGS. 10A and 10B. Arise.

  A specific occurrence of bonding failure will be described with reference to schematic explanatory views of FIGS. 11A, 11B, and 11C. In the schematic explanatory views of FIGS. 11A, 11B, and 11C, the case where each bump 505 is formed on the LED 501 side is shown.

  As shown in FIG. 11A, metal bonding is started between each bump 505 and each substrate electrode 504 by applying ultrasonic vibration, and when the metal bonding proceeds, next, as shown in FIG. The bumps 505 and the respective pads 502 of the LED 501 are joined by applying ultrasonic vibration. As the bonding of the bumps 505 made of gold and the pads 502 made of aluminum proceeds, the diffusion of gold and aluminum proceeds, and as shown in FIG. And an alloy layer 505a of gold are formed, and the alloy layer 505a is increased by the addition of ultrasonic vibration. Since this alloy layer 505a has a characteristic that it is harder and more brittle than the bump 505 made of gold, stress concentration occurs in the body of the LED 501 due to the addition of ultrasonic vibration, and cracks occur in the LED 501. There is a case. In particular, such a problem becomes conspicuous due to the increase in the bonding time due to the use of the bump 501 having a large size.

  Further, in the LED 501, since each bump 505 is formed by a plating method, the formation height of each bump 505 is often slightly different as shown in FIG. 12A. In such a case, as shown in FIG. 12B, the bump 505 having a higher formation height comes into contact with the substrate electrode 504 of the substrate 503 first, so that the bump 505 has a lower formation height. Bonding is completed earlier than the bump 505. As shown in FIG. 12C, even after one bump 505 is bonded first, if the application of ultrasonic vibration for bonding the other bump 505 is continued, stress concentration occurs in the one bump 505. In some cases, cracks are generated.

  Further, in order to make the formation heights of the respective bumps 505 uniform, it is conceivable to perform a process for making the formation heights uniform, but each bump 505 is formed by a plating method. However, the polishing process requires a lot of processing time and labor, although it is necessary to perform a polishing process.

  In addition, the plating method employed for forming the large bump 505 on each pad 502 of the LED 501 requires many processing steps as described above, and requires time and labor. For example, it may take about 3 days to apply the plating method. In addition, each bump 505 formed by the plating method needs to be subjected to an inspection process, and further requires time and labor.

  On the other hand, solder bumps are formed on the respective pads of the LEDs without performing bonding by applying ultrasonic vibration accompanied with such various problems, and the solder bumps are reflowed to bond the LED and the substrate. It can also be done. However, in such a reflow mounting method using solder bumps, in order to melt the solder bumps, for example, each solder bump needs to be heated to 238 ° C. or higher. The reflow mounting method cannot be applied to LED mounting because the temperature is about ℃ or less. There is also a problem that the light emitting surface of the LED is contaminated with gas components or the like in the reflow atmosphere during the reflow, and the light emitting function is deteriorated.

  In addition, even if the semiconductor element is not an LED and the allowable temperature is 238 ° C. or higher, a flux supply process and a cleaning process associated with the use of solder are necessary, and the reflow mounting method is implemented. Takes time and effort. Also, the use of such solder is contrary to the lead-free measures for dealing with recent environmental problems.

  Accordingly, an object of the present invention is to solve the above-described problem, and in mounting the semiconductor element on the substrate by bonding the substrate electrode of the substrate and the element electrode of the semiconductor element by applying ultrasonic vibration, An object of the present invention is to provide a semiconductor element mounting method and a semiconductor element mounting substrate capable of reducing the occurrence of bonding failure due to the application of ultrasonic vibration and performing reliable and efficient bonding.

  In order to achieve the above object, the present invention is configured as follows.

According to the first aspect of the present invention, a semiconductor element having a device electrode that can be bonded to a substrate electrode of a substrate is mounted on the substrate by bonding the substrate electrode and the device electrode. In the method
A bonding member formed of a paste-like conductive material is disposed between the element electrode and the substrate electrode, and the element electrode and the substrate electrode are brought into contact with each other with the bonding member interposed therebetween,
Provided is a semiconductor element mounting method in which the bonding member is bonded to the substrate electrode and the element electrode by applying ultrasonic vibration to the bonding member and the element electrode or the substrate electrode in the contact state. To do.

According to the second aspect of the present invention, the semiconductor element having a plurality of element electrodes that can be bonded to the respective substrate electrodes of the substrate is bonded to the respective substrate electrodes and the respective element electrodes, thereby In the mounting method of the semiconductor element mounted on the substrate,
A bonding member formed of a paste-like conductive material is disposed between each element electrode and each substrate electrode, and each element electrode and each substrate electrode are bonded to each other. Abutting through the members,
In the contact state, by applying ultrasonic vibration to the respective bonding members and the respective element electrodes or the substrate electrodes, the respective bonding members, the respective substrate electrodes, and the respective element electrodes, Provided is a method for mounting a semiconductor element that joins.

According to the third aspect of the present invention, the paste-like conductive material is supplied or applied to each of the substrate electrodes or each of the element electrodes,
Each of the joining members is formed by applying energy to the supplied paste-like conductive material,
The semiconductor element mounting method according to the second aspect, in which each of the element electrodes and each of the substrate electrodes are brought into contact with each other with the respective joining members interposed therebetween.

  According to the fourth aspect of the present invention, after the paste-like conductive material is supplied, the energy is applied to stabilize the shape formed by the paste-like conductive material. A method for mounting a semiconductor element according to the third aspect for forming each of the joining members is provided.

  According to a fifth aspect of the present invention, the paste-like conductive material is a gold nanopaste, and the bonding material is a metal film generated by applying the energy to the gold nanopaste. A method for mounting a semiconductor device according to the third aspect or the fourth aspect is provided.

  According to the sixth aspect of the present invention, by pressing the respective element electrodes relative to the respective substrate electrodes while interposing the respective bonding members, the respective bonding members are deformed. The method for mounting a semiconductor element according to any one of the third to fifth aspects, wherein the contact between each element electrode and each substrate electrode through the respective joining members is provided. To do.

  According to a seventh aspect of the present invention, there is provided mounting of the semiconductor element according to any one of the third to sixth aspects, wherein a plurality of the joining members are formed on each of the substrate electrodes or the individual element electrodes. Provide a method.

  According to the eighth aspect of the present invention, the application of the ultrasonic vibration to each of the joining members is such that the held surface, which is the surface opposite to the formation surface of each of the element electrodes in the semiconductor element, is a component. The semiconductor element according to any one of the third to seventh aspects, wherein the ultrasonic vibration is applied through the semiconductor element by the component holding member while being held by the holding surface of the holding member. Provide an implementation method.

According to a ninth aspect of the present invention, the semiconductor element has a P-type electrode and an N-type electrode having different thickness dimensions as the respective element electrodes,
Depending on the difference in distance between each element electrode and each substrate electrode due to the difference in thickness between the P-type electrode and the N-type electrode, the thickness dimension of each of the bonding members is As differently, the semiconductor element mounting method according to any one of the third aspect to the eighth aspect, in which the respective joining members are formed, is provided.

According to a tenth aspect of the present invention, the semiconductor element has a plurality of protruding electrodes formed on the respective element electrodes,
While supplying the paste-like conductive material to each of the protruding electrodes or each of the substrate electrodes, and applying energy to the paste-like conductive material, the respective bonding members are formed,
The semiconductor element mounting method according to the second aspect, in which each of the element electrodes and each of the substrate electrodes are brought into contact with each of the bonding members and the protruding electrodes, respectively.

  According to an eleventh aspect of the present invention, there is provided the semiconductor element mounting method according to the tenth aspect, wherein each protruding electrode is formed using a conductive material by a plating method.

According to a twelfth aspect of the present invention, the semiconductor element includes a P-pole electrode and an N-pole electrode having different thickness dimensions as the respective element electrodes,
Depending on the difference in distance between the tip of each protruding electrode and each substrate electrode caused by the difference in the height of the tip of each protruding electrode based on the difference in thickness of each element electrode Then, the semiconductor element mounting method according to the tenth aspect or the eleventh aspect, in which the respective joining members are supplied so that the thickness dimensions of the respective joining members are different, is provided.

According to a thirteenth aspect of the present invention, the substrate has a plurality of protruding electrodes formed on the respective substrate electrodes,
While supplying the paste-like conductive material to each of the protruding electrodes or each of the element electrodes, and applying energy to the paste-like conductive material, the respective bonding members are formed,
The semiconductor element mounting method according to the second aspect, in which each of the element electrodes and each of the substrate electrodes are brought into contact with each of the bonding members and the protruding electrodes, respectively.

According to a fourteenth aspect of the present invention, the semiconductor element has a P-pole electrode and an N-pole electrode having different thickness dimensions as the respective element electrodes,
According to the difference in the distance between the respective element electrode and the tip of each protruding electrode caused by the difference in the thickness of each of the element electrodes, the thickness of each of the bonding members may be different. Furthermore, the semiconductor element mounting method according to the thirteenth aspect for supplying the respective joining members is provided.

  According to a fifteenth aspect of the present invention, before the contact of the respective element electrodes of the semiconductor element and the respective substrate electrodes of the substrate with the respective joining members interposed therebetween, the substrate A method for mounting a semiconductor device according to any one of the third to fourteenth aspects is provided, in which a plasma cleaning process is performed on each of the substrate electrodes.

  According to the sixteenth aspect of the present invention, after joining the respective element electrodes of the semiconductor element and the respective substrate electrodes of the substrate through the respective joining members, the periphery of the joined portion is formed. A method for mounting a semiconductor element according to any one of the third to fifteenth aspects, in which a sealing process is performed with an insulating material.

  According to a seventeenth aspect of the present invention, the semiconductor element is an LED element, and each of the joining members has a function of transferring heat generated by voltage application to the LED element to the substrate side. A method for mounting a semiconductor device according to any one of the third to sixteenth aspects is provided.

According to an eighteenth aspect of the present invention, a substrate having a plurality of substrate electrodes;
A semiconductor element having a plurality of element electrodes electrically connectable to the respective substrate electrodes;
A plurality of bonding members disposed between each of the substrate electrodes and each of the element electrodes and formed into a metal film by applying energy to the gold nanopaste;
The respective bonding members are bonded to the respective substrate electrodes or the respective element electrodes by adhesion, so that the respective substrate electrodes and the respective element electrodes are interposed with the respective bonding members. Provided is a semiconductor element mounting substrate, wherein the semiconductor element is mounted on the substrate by bonding.

According to a nineteenth aspect of the present invention, in the semiconductor element mounting method of mounting a semiconductor element having a plurality of element electrodes on a substrate having a plurality of substrate electrodes,
A bonding member formed by applying energy to the paste-like conductive material is disposed between each of the element electrodes and each of the substrate electrodes, and each of the element electrodes and each of the substrates is disposed. Each of the element electrodes is deformed by pressing the respective element electrodes relative to the respective substrate electrodes while interposing the respective bonding members with the electrodes, and deforming the respective bonding members. A method of mounting a semiconductor element is provided, wherein each of the substrate electrodes is brought into contact with each of the bonding members.

  According to the first aspect or the second aspect of the present invention, each element electrode of the semiconductor element and each substrate electrode of the substrate have a high hardness of about 70 to 90 HV, for example. However, it is difficult to secure a sufficient contact area simply by applying ultrasonic vibration in a state in which the element electrode and each substrate electrode are used. In between, a bonding member formed of a paste-like conductive material which is a soft material is disposed, and the respective bonding members having hardness sufficiently lower than the hardness of the element electrode and the substrate electrode are interposed. Sufficient metal bonding can be performed by applying ultrasonic vibration while bringing the element electrodes and the substrate electrodes into contact with each other.

  That is, at the time of the contact, each of the bonding members having a property that is softer than the element electrode or the substrate electrode is pressed between the element electrode and the substrate electrode to make a minute amount. By deforming, the respective element electrodes and the respective substrate electrodes can be reliably brought into contact with each other through the respective bonding members. Further, at the time of this contact, a sufficient bonding area (contact area) is secured at the contact portion between each of the element electrodes or each of the substrate electrodes and each of the bonding members. By applying ultrasonic vibration in such a state, metal bonding can be performed reliably and with sufficient bonding strength in the above-described sufficient bonding area, and stable bonding can be performed.

  According to the third aspect or the fourth aspect of the present invention, each of the bonding members is arranged by applying or printing the paste-like conductive material on each of the element electrodes or each of the substrate electrodes. After supplying by using the means, each of the joining members can be formed by applying energy to the supplied paste-like conductive material. That is, such a coating or printing means can be used because the conductive material is a paste having a soft property. Further, the above-mentioned energy is applied to such a soft conductive material, for example, thermal energy, ultrasonic energy, or electron beam is applied to stabilize the shape of the paste-like conductive material. Can be made. By performing such stabilization, each of the joining members can be easily deformed by applying an external force, but can be held in a stable state when no external force is applied. Can do. Therefore, by using such a coating or printing means, the supply amount of the conductive material can be controlled with high accuracy, and the formation of the respective joining members can be performed with high accuracy. At the same time, the shape formed by supplying the paste-like conductive material having a soft property can be held in a stabilized state, and more reliable contact and joining can be performed.

  According to another aspect of the present invention, the paste-like conductive material is a gold nanopaste, thereby forming a joining member suitable in terms of conductivity, thermal conductivity, oxidation resistance, and the like. Can do. In particular, by using the gold nanopaste, it is possible to apply the energy to the gold nanopaste to form a metal film, thereby realizing more stable and reliable bonding.

  Further, while interposing each of the bonding members, the respective element electrodes are pressed against each of the substrate electrodes, and the respective bonding members are deformed, whereby each of the element electrodes and the above-described bonding members are deformed. By making contact with each of the substrate electrodes through the respective joining members, there is a variation in the formation thickness of the respective element electrodes and the formation thickness of the respective substrate electrodes. Even if it is a case, the said dispersion | variation can be absorbed by deform | transforming said each joining member, and reliable joining can be performed.

  Further, by forming a plurality of the joining members on each of the substrate electrodes or the individual element electrodes, the ratio of the formation width to the formation height of the joining members can be reduced, and the ultrasonic vibration can be reduced. By giving, it can be set as the shape which each said joining member deform | transforms more easily. Therefore, the application time of the ultrasonic vibration for the bonding can be shortened, and bonding by applying ultrasonic vibration more efficiently and stably can be performed.

  Further, the tip of each element electrode in the semiconductor element having a feature that the formation thicknesses of the P-type electrode and the N-type electrode as the respective element electrodes are different from each other and the respective substrate electrodes of the substrate. By adjusting the supply amount of the conductive material, for example, gold nano paste, according to the difference in distance dimension between the above, by forming the respective joining members so that the respective thickness dimensions are different, While coping with the difference in formation thickness (height) between the P-type electrode and the N-type electrode, it is possible to perform reliable and stable mounting. That is, even when the formation thicknesses of the respective element electrodes are different from each other, the difference is adjusted by the respective bonding members, and the difference between the semiconductor element and the substrate is adjusted. The semiconductor element can be mounted while maintaining the level. In particular, such an effect can be effectively obtained when the semiconductor element is an LED element having the above-described characteristics.

  In addition, such an effect can be obtained even when each protruding electrode is formed on each element electrode of the semiconductor element or each substrate electrode of the substrate. Can do.

  Before continuing the description of the present invention, the same parts are denoted by the same reference numerals in the accompanying drawings.

  Embodiments according to the present invention will be described below in detail with reference to the drawings.

(First embodiment)
FIG. 1 is a schematic explanatory view showing a planar structure of an LED chip (or LED element) mounted on a substrate as an example of the semiconductor element in the semiconductor element mounting method according to the first embodiment of the present invention. .

  As shown in FIG. 1, an LED (Light Emitting Diode) chip 1 has a substantially square shape, and a plurality of pads 2, which are examples of element electrodes, are formed on the surface on the bonding side to the substrate. Is formed. Each of the pads 2 includes a P-pole pad (which is an example of a P-type electrode) 2p formed in an oval shape and an N-pole pad (an N-type electrode) formed in a substantially circular shape depending on the characteristics of the LED chip 1. It is divided into two types (2n), which is an example. For example, the P-pole pad 2p is formed to a size of about 0.6 mm × 0.1 mm, and the N-pole pad 2n is formed to a size of about 0.1 mm in diameter.

  A schematic cross-sectional view of the LED chip 1 is shown in FIG. As shown in FIG. 2, the LED chip 1 has a multilayer structure, and the formation height of the P-pole pad 2p and the N-pole pad 2n on the pad formation surface on which the respective pads 2 are provided. Each pad 2 is formed so that (formation thickness) is different. Such a difference in the formation height of each pad 2 is caused by the characteristics of the LED chip 1. For example, in the state where the pad formation surface of the LED chip 1 is disposed on the upper surface, the P pole The pad 2p is positioned above the N-pole pad 2n, and the difference in formation height from each other is about 2 μm.

  3A shows a schematic cross-sectional view of the LED chip 1, and FIG. 3B shows a schematic cross-sectional view of the substrate 3 on which the LED chip 1 shown in FIG. 3A is mounted. As shown in FIG. 3A, each pad 2 of the LED chip 1 is formed with bumps 5 which are examples of protruding electrodes. Such bumps 5 can be formed by plating with gold (Au), which is an example of a conductive material, for example. Further, as shown in FIG. 3B, the substantially flat substrate 3 has a plurality of substrate electrodes 4 formed on the surface on which the LED chip 1 is mounted, which is the upper surface in the drawing. The arrangement of the substrate electrodes 4 on the surface of the substrate 3 is formed so as to correspond (match) with the arrangement of the pads 2 in the LED chip 1. Since the respective pads 2 and the substrate electrodes 4 are thus formed, the respective pads 2 of the LED chip 1 are arranged on the respective substrate electrodes 4 of the substrate 3 with the respective bumps 5 interposed therebetween. It is possible to join. The substrate in the present invention includes a circuit substrate such as a silicon (Si) wafer, a resin substrate, a paper-phenol substrate, a ceramic substrate, a glass / epoxy (glass epoxy) substrate, a film substrate, a single layer substrate or a multilayer substrate. An object on which a circuit is formed, such as a substrate, a component, a housing, or a frame, is included.

  However, in the LED chip 1 as described above, the P electrode pad 2p and the N electrode pad 2n have different formation heights, and thus are formed by the plating method or the like. The tip height position of the bump 5 also differs depending on the difference in the formation height. 4A shows a mounting method for mounting the LED chip 1 on the substrate 3 without being affected by the difference in the formation heights of the respective pads 2. It demonstrates below using the explanatory drawing using the schematic cross section of the LED chip 1 and the board | substrate 3 which are shown to (B), (C), (D), (E), and (F).

  First, as shown in FIG. 4A, bumps (gold bumps) 5 are formed on the upper surfaces of the P-electrode pad 2p and the N-electrode pad 2n of the LED chip 1 by using, for example, gold by plating. The P electrode pad 2p and the N electrode pad 2n have a difference in formation height of, for example, about 2 μm. However, when forming each bump 5 by a plating method, the formation height of each bump 5 is changed. Since it is difficult to make these different, the respective bumps 5 are formed with substantially the same formation height. Therefore, as shown in FIG. 4A, the illustrated tip height position of the bump 5 formed on the P pole pad 2p and the illustrated tip height position of the bump 5 formed on the N pole pad 2n are mutually different. For example, the difference is about 2 μm.

  Next, or in parallel with each of the above-described bump forming steps, a gold nano paste that is an example of a paste-like conductive material is provided on the upper surface of each substrate electrode 4 on the substrate 3 on which the LED chip 1 is mounted. (It is also an example of a metal nanopaste) is supplied using the means of application | coating or printing, and the some joining electrode 6 which is an example of a joining member is formed. Note that a plasma cleaning process may be performed on each substrate electrode 4 of the substrate 3 before the formation of the bonding electrode 6. In such a case, the surface of each substrate electrode 4 can be cleaned, and the adhesion between the surface of each substrate electrode 4 and the gold nanopaste supplied to the surface is good. It is because it can be made.

  Here, as shown in FIG. 4C, the “gold nanopaste” means a large number of gold nanoparticles (conductive particles) 9a that are ultrafine gold particles formed of gold, and an additive component 9b (for example, , Including adhesive components and various additives, and not necessarily limited to the case where each component has conductivity). Further, this gold nanopaste is a soft material having a characteristic that it has plasticity such that its shape (form) can be easily changed by applying an external force.

  However, the gold nanopaste has the characteristic that it is very soft as it is, and the hardness that the shape can be greatly changed even when a slight external force is applied when the shape cannot be stably held or Has viscosity. Such a soft property is suitable when a coating or printing means is used, but some processing is required from the viewpoint of the stability of the shape. Accordingly, in the first embodiment, energy is applied to the gold nanopaste in a state of being supplied by coating or printing, for example, by adding energy such as heat, ultrasonic waves, or electronic heat. By promoting the active evaporation of the component 9b and bringing the distance between the individual gold nanoparticles 9a close to each other, or by promoting the bonding between the gold nanoparticles 9a, the hardness and the like are improved from the above supply state, The bonding electrode 6 is formed. For example, a metal film can be formed by applying energy to the gold nanopaste. The joining electrode 6 formed in this way has a hardness and a viscosity that can stably hold the shape if no external force is applied, and a positive external force is applied at one end. The shape can be easily changed, and the plasticity that the deformed shape can be maintained by stopping the application of the external force (that is, a state that is more stable than the gold nano paste immediately after the supply) Plasticity). Therefore, it can be said that the process by such energy application is a stabilization process for the gold nanopaste.

  Here, the mechanism of the stabilization process by energy application to such a gold nanopaste will be described in detail with reference to schematic cross-sectional views shown in FIGS. 17A, 17B, 17C, and 17D.

  First, as shown in FIG. 17A, the gold nanopaste is composed of a large number of gold nanoparticles 9a and an additive component 9b. As such an additive component 9b, for example, a dispersing agent (hereinafter referred to as dispersing agent 9b) in which the individual gold nanoparticles 9a exist independently without being fused to each other is used. As shown to 17A, the surface of each gold | metal | money nanoparticle 9a is made into the state covered with the dispersing agent 9b, and is made into the state which exists mutually independently. Such gold nanoparticles 9a that exist independently are referred to as independently dispersed nanoparticles.

  When energy such as heat or electron beam is applied to the gold nanopaste in such a state, as shown in FIG. 17B, the dispersant 9b covering the surface of each gold nanoparticle 9a It peels from the surface of the nanoparticle 9a, and is then gasified and evaporated. As the dispersant 9b is peeled in this way, the rare outer surface of each gold nanoparticle 9a is exposed, and as a result, as shown in FIG. 17C, it is located in the vicinity. The fusion of the gold nanoparticles 9a is started.

  When such fusion is promoted, as shown in FIG. 17D, a plurality of gold nanoparticles 9a are fused together to form gold particles 9c larger than the original gold nanoparticles 9a. As a result, the gold nanopaste having soft characteristics is made into a gold bulk (solid) state. Such a series of mechanisms can be referred to as a gold nanopaste sintering mechanism.

  In the first embodiment, the bonding electrode 6 formed by solidifying the gold nanopaste, that is, the stabilization process, can be easily deformed by applying an external force. However, when the energy is applied, the above characteristics can be obtained by setting conditions for energy intensity and application time.

  Specific examples of the gold nano paste application or printing include, for example, a method of supplying gold nano paste using a screen and a squeegee, and a method of supplying gold nano paste using an ink jet method or the like. . Further, unlike the formation height of each bump 5 formed by the above-described plating method, according to the gold nano paste supply method, the supply amount of the gold nano paste can be precisely controlled. Each joining electrode 6 can be formed while controlling the formation height minutely. The formation height (thickness) of each bonding electrode 6 is, for example, about 20 μm. Further, supply of the gold nano paste to the respective substrate electrodes 4 of the substrate 3 in consideration of the difference in the tip height positions of the bumps 5 formed on the P-electrode pad 2p and the N-electrode pad 2n of the LED chip 1, respectively. The bonding electrode 6 is formed such that the amount is adjusted and the respective formation heights (thicknesses) are different from each other. That is, as shown in FIG. 4D, the LED chips 1 are substantially parallel to each other above the substrate 3 (ie, in a substantially horizontal state) with the respective pads 2 and the respective substrate electrodes 4 being aligned. In accordance with the difference in the distance between the tip of each bump 5 and each substrate electrode 4 of the substrate 3 based on the difference in tip height position of each bump 5 of the LED chip 1. The respective formation thicknesses are determined, and the respective junction electrodes 6 are formed. That is, the distance between the tip of the bump 5 formed on the P-electrode pad 2p and the substrate electrode 4 is larger than the distance between the tip of the bump 5 formed on the N-electrode pad 2n and the substrate electrode 4. In consideration of the shortness, the formation thickness dimension of the bonding electrode 6 disposed between the bump 5 of the P-electrode pad 2p and the substrate electrode 4 is set between the bump 5 of the N-electrode pad 2n and the substrate electrode 4. Each joining electrode 6 is formed so as to be smaller than the formation thickness dimension of the joining electrode 6 to be arranged by a difference in mutual distance. The stabilization process for the gold nano paste is not limited to the case where energy is applied as described above. For example, the stabilization process is performed by leaving the gold nano paste for a predetermined time. There may be. Even in such a case, evaporation of the additive component 9b contained in the gold nanopaste can be promoted, the gold nanoparticles 9a can be brought closer to each other, and the conductivity of the bonding electrode 6 can be improved. It is because it can raise. However, it is preferable to perform the active stabilization process by applying energy from the viewpoint of shortening the mounting time and from the viewpoint of quickly holding the shape formed by coating or printing.

  Thereafter, as shown in FIG. 4D, the alignment of the LED chip 1 and the substrate 3 is performed. For such alignment, for example, a suction surface 7a (illustrated upper surface), which is the surface opposite to the pad forming surface on which the pads 2 of the LED chip 1 are formed, is a suction nozzle 7 which is an example of a component holding member. While holding the suction surface by the holding surface 7a, the LED chip 1 and the substrate 3 which are arranged substantially parallel to each other are relatively moved so that the respective pads 2 and the respective substrate electrodes 4 are aligned. Done by doing.

  After such alignment, as shown in FIG. 4E, the suction nozzle 7 is lowered, and the tip of each bump 5 of the LED chip 1 is joined to each substrate electrode 4 of the substrate 3. The electrodes 6 are brought into contact with each other. At the time of this contact, since the bonding electrodes 6 are formed so that the thickness dimensions are different according to the difference in distance dimension between the tip of each bump 5 and each substrate electrode 4, respectively. The tips of the bumps 5 come into contact with the bonding electrodes 6 almost simultaneously. Accordingly, the LED chip 1 and the substrate 3 are brought into contact with each other while maintaining the parallel state of each other. After this contact, the lowering of the suction nozzle 7 is stopped and the contact state is maintained. Incidentally, by utilizing the fact that each bonding electrode 6 is formed of gold nanopaste and has a soft property, after the contact, the suction nozzle 7 is further lowered by a minute amount, respectively. The bumps 5 may be pressed (pressed) to slightly deform the respective bonding electrodes 6. In such a case, even if the formation heights of the respective bumps 5 are different due to errors in the formation accuracy thereof, the respective bonding electrodes 6 are slightly deformed, Each bump 5 and each bonding electrode 6 can be reliably brought into contact with each other while ensuring a sufficient contact area.

  Thereafter, as shown in FIG. 4E, ultrasonic vibration is applied to the LED chip 1 from the suction nozzle 7 while maintaining this contact state. This ultrasonic vibration is transmitted to each pad 2, bump 5, bonding electrode 6, and substrate electrode 4. By applying this ultrasonic vibration, new surfaces that are not contaminated with organic matter or the like are cut out at the tip surfaces of the respective bumps 5 that are pressed against each other and the upper surfaces of the respective bonding electrodes 6. Each new surface is adhered to each other to be in a metal-bonded state. Further, as described above, since each bump 5 and each bonding electrode 6 are in a state where a sufficient contact area is ensured and reliably contacted, such metal bonding is performed in each bump. 5 is performed almost simultaneously. In addition, the application of such ultrasonic vibration by the suction nozzle 7 is applied for a predetermined time in order to reliably perform the metal joining.

  By performing the metal bonding in this way, each pad 2 of the LED chip 1 is bonded to each substrate electrode 4 of the substrate 3 via each bump 5 and each bonding electrode 6. Become. Thereafter, the suction holding of the LED chip 1 by the suction nozzle 7 is released, and the suction nozzle 7 is raised. Thereby, the LED chip 1 is mounted on the substrate 3, and the LED chip mounting substrate 10 which is an example of the semiconductor element mounting substrate is completed. As shown in FIG. 4F, an insulating material is formed between the surface of the LED chip 1 where the respective pads 2 are formed and the surface of the substrate 3 where the respective substrate electrodes 3 are formed. By injecting a sealing material as an example, it is possible to form a sealing member 8 and perform a sealing process, thereby reliably protecting the joint portion between the LED chip 1 and the substrate 3.

  In the above description, the case where, for example, a gold nano paste is used as the paste-like conductive material has been described. However, the first embodiment is not limited to such a case. Instead of such a case, for example, a silver (Ag) nano paste may be used. Silver nanopaste has the advantage of being cheaper than gold nanopaste. However, silver nanopaste is easier to oxidize than gold nanopaste, and is prone to migration, so in cases where more stable, reliable and highly accurate bonding is required. It is preferable to use gold nano paste.

  In the above description, the case where one bonding electrode 6 is formed on the upper surface of each substrate electrode 4 has been described. However, the first embodiment is not limited to such a case. Instead of such a case, for example, a plurality of bonding electrodes 6a are formed such that a plurality of protrusions are formed on the upper surface of one substrate electrode 4 as in the schematic enlarged cross-sectional view of the substrate electrode 4 shown in FIG. May be formed. In such a case, since the formation width can be made smaller than the formation height of each bonding electrode 6a, each bonding electrode 6a is more easily deformed by applying ultrasonic vibration. (Aspect ratio). Therefore, it is possible to shorten the time required for joining by applying ultrasonic vibrations, and it is possible to perform more reliable and stable joining by having the shape that easily deforms. Each of the bonding electrodes 6a can be formed by printing using, for example, an ink jet method using a gold nano paste. The individual bonding electrodes 6a are formed, for example, with a formation width of about 20 μm and a formation height of about 20 μm. The formation interval (formation pitch) of each bonding electrode 6a is desirably set to an optimal value according to the bonding state and the like.

  In the above description, the case where each bonding electrode 6 is formed on the upper surface of each substrate electrode 4 of the substrate 3 has been described. However, the first embodiment is not limited to such a case. Absent. Instead of such a case, for example, as shown in FIG. 7, each bonding electrode 6 b may be formed on each bump 5 of the LED chip 1. This is because even in such a case, the respective pads 2 can be brought into contact with the respective substrate electrodes 4 with the respective bumps 5 and bonding electrodes 6b interposed therebetween.

  Further, for example, instead of the case where the respective bumps 5 formed by the plating method are formed on the respective pads 2 of the LED chip 1, as shown in FIGS. There may be a case where each bump 5 is formed on each substrate electrode 4 and bonding is performed by applying the ultrasonic vibration. In contrast to the LED chip 1 in which the formation height of each pad 2 is different, the formation height of each substrate electrode 4 is substantially uniform in the substrate 3, so that the plating method is more efficient. There is an advantage that each bump can be formed. Further, as shown in FIGS. 16A and 16B, the bumps 5A and 5B are formed on both the pads 2 of the LED chip 1 and the substrate electrodes 4 of the substrate 3, respectively. May be.

  According to the first embodiment, the following various effects can be obtained.

  First, each bump 5 formed by plating on each pad 2 of the LED chip 1 has a high hardness of about 80 to 90 HV, and each substrate electrode 4 of the substrate 3 also has a hardness of 70 to 70-. Since it is as high as about 90 HV, it is difficult to generate bump crushing by simply applying ultrasonic vibration in a state where both are in contact with each other, and it is difficult to perform sufficient metal bonding. Between the substrate electrode 4 and each of the substrate electrodes 4, a bonding electrode 6 formed of a metal film generated by applying energy to a gold nanopaste, which is a soft conductive paste-like conductive material, is disposed. By applying the ultrasonic vibration while the respective bumps 5 and the respective substrate electrodes 4 are brought into contact with each other by interposing the respective bonding electrodes 6 having hardness sufficiently lower than the respective hardnesses, Enough metal contact It can be carried out.

  That is, at the time of the contact, the respective bonding electrodes 6 that are softer than the bumps 5 and the like are pressed between the respective bumps 5 and the substrate electrode 4 to be minutely deformed, whereby the respective bumps 5. And the substrate electrode 4 can be reliably brought into contact with each other via the respective joining electrodes 6. Further, at the time of this contact, a sufficient bonding area (contact area) is secured at the contact portion between each bump 5 and each bonding electrode 6. By applying ultrasonic vibration in such a state, metal bonding can be performed reliably and with sufficient bonding strength in the above-described sufficient bonding area, and stable bonding can be performed. Further, since each bonding electrode 6 formed of the same material is interposed between each bump 5 and each substrate electrode 4, the bonding conditions between each bump 5 and the substrate electrode 4 are the same. Can be. Therefore, since the bonding of the bumps 5 and the substrate electrode 4 with the bonding electrode 6 interposed can be performed simultaneously, the occurrence of stress concentration due to the bonding of some bumps or the like first. Problems can be prevented in advance, and more accurate and stable bonding can be performed.

  Also, the bumps 5 formed by plating may have different formation heights depending on the formation accuracy, but even when there is a variation in the formation heights, the respective bumps 5 are formed. Since the bonding electrode 6 is formed of a gold nano paste that is a soft material, each of the bumps 5 and the substrate electrode 4 can be accommodated while absorbing the variation in the formation height of each bump 5 by each bonding electrode 6. Can be reliably brought into contact with each other by interposing the respective joining electrodes 6, and reliable and stable joining can be performed by applying ultrasonic vibration.

  In addition, it is possible to stably hold the shape by applying energy to the gold nanopaste having a characteristic that it is too soft to hold the shape and applying energy after supply by coating or printing. And reliable contact and joining can be realized. In particular, such a stabilization process can be performed by applying energy such as heat, ultrasonic waves, or an electron beam without using a special chemical solution or the like, so that a quick and reliable process can be realized.

  In addition, by applying ultrasonic vibration in a state where the respective bumps 5 are reliably brought into contact with the substrate electrodes 4 with the respective bonding electrodes 6 interposed therebetween, the respective bumps 5 are formed. The tip and each of the bonding electrodes 6 can be bonded substantially simultaneously, and the time required for the bonding can be shortened. Therefore, it is possible to prevent the occurrence of the problem of bonding failure due to the fact that bonding is not performed substantially simultaneously and the time required for bonding becomes long.

  In addition, each bonding electrode 6 formed of gold nano paste to which energy is applied has a characteristic that its hardness is remarkably lower and softer than that of the bump 5 or the like, and therefore, the bump 5 having a high hardness. In addition, it is possible to reduce the occurrence of the problem of causing cracks in the bumps 5 without causing stress concentration due to the addition of ultrasonic vibration.

  Further, the distance between the tip of each bump 5 formed on the LED chip 1 having the feature that the formation height of the P-electrode pad 2p and the N-electrode pad 2n is different from each substrate electrode 4 of the substrate 3. By adjusting the supply amount of the gold nanopaste according to the difference in size, the respective bonding electrodes 6 are formed so as to have different thickness dimensions, whereby the P-electrode pad 2p and the N-electrode pad 2n While dealing with the difference in formation height, it is possible to perform reliable and stable mounting. That is, even in the case where the formation heights of the respective pads 2 are different as described above, the difference is adjusted by the respective bonding electrodes 6, and the horizontal between the LED chip 1 and the substrate 3 is adjusted. The LED chip can be mounted while maintaining the degree.

  In addition, the formation of such a bonding electrode 6 is performed while finely controlling the supply amount of gold nanopaste by means such as coating or printing, utilizing the property of being a soft paste-like material. Therefore, the thickness dimension can be reliably controlled.

  Since the ultrasonic bonding (metal bonding) can be realized using the gold nanopaste as described above, the allowable temperature is about 200 ° C. or less, the allowable temperature is lower than the melting point of solder 238 ° C., and the heat The LED chip 1 having a characteristic of being weak to the above can be mounted on the substrate 3 without using solder reflow. Thereby, it is possible to prevent the LED chip from being damaged by heat or generated gas during the conventional solder reflow. Further, it is possible to eliminate the flux supply process and the cleaning process that are necessary in connection with the use of solder, and it is possible to reduce time and labor and enable efficient mounting. At the same time, it can deal with recent environmental problems.

  Therefore, according to the mounting method of the first embodiment, each pad 2 formed in a large size in order to efficiently release the heat generated with the voltage application to the LED chip 1 to the substrate 3 side. By using the bonding electrode 6, the bump 5 and the substrate electrode 4 can be bonded to each other effectively and effectively with sufficient ultrasonic vibration, and while shortening the vibration applying time, reliably and efficiently. Can be done.

(Second Embodiment)
In addition, this invention is not limited to the said embodiment, It can implement with another various aspect. For example, the mounting method of the LED chip 1 which is an example of the mounting method of the semiconductor element concerning the 2nd Embodiment of this invention is demonstrated using the schematic explanatory drawing shown to FIG. 5E. In addition, the same reference number is attached | subjected about the same component which the LED chip 1 and the board | substrate 3 in the said 1st Embodiment have for the purpose of making an understanding of the description easy.

  First, as shown in FIG. 5A, bumps 5 are formed on the upper surfaces of the respective pads 2 on the upper surface of the LED chip 1 as in the first embodiment. Each such bump 5 is formed using gold by a plating method, for example. Further, since there is a difference in formation height between the P-electrode pad 2p and the N-electrode pad 2n of the LED chip 1 (for example, there is a difference in formation height of 2 μm), the height of the tip of each formed bump 5 is high. There are similar height differences in position.

  Further, as shown in FIG. 5B, gold nano paste is supplied to the upper surface of each substrate electrode 4 in the substrate 3 by using a coating or printing means, and each bonding electrode 16 is formed. Each of the bonding electrodes 16 formed in this way is formed with a formation thickness of approximately 20 μm, for example, in a substantially uniform thickness unlike the case of the first embodiment. In addition, by applying predetermined energy to the gold nano paste supplied in this way, each bonding electrode 16 is formed in a state where the shape is stabilized.

  Thereafter, as shown in FIG. 5C, the surface of the LED chip 1 on which the pads 2 are not formed is sucked and held by the suction nozzle 7 and placed above the substrate 3. Each pad 2 and each substrate electrode 4 of the substrate 3 are aligned in the direction along the surface of the substrate 3 so that they can be bonded to each other.

  After this alignment, the suction nozzle 7 is lowered to lower the LED chip 1 so that the tips of the respective bumps 5 of the LED chip 1 are brought into contact with the respective bonding electrodes 16. At this time, as described above, since the height positions of the tips of the respective bumps 5 are different from each other, the bumps 5 formed on the P-electrode pad 2p are bumps formed on the N-electrode pad 2n. Prior to 5, the contact is made with the bonding electrode 16. After the contact, the suction nozzle 7 is continuously lowered slightly, and the bonding electrode 16 in the contact state is pressed and deformed by the bump 5 formed on the P-electrode pad 2p. Let By deforming the bonding electrode 16 in this manner, the bump 5 formed on the N-pole pad 2n that has not been in contact can be further lowered. As shown in FIG. 5D, the bump 5 Can be brought into contact with the bonding electrode 16. The lowering operation of the suction nozzle 7 is stopped while maintaining the contact state, that is, the state in which each bonding electrode 16 is in contact with and pressed against each bump 5.

  Thereafter, as shown in FIG. 5D, ultrasonic vibration is applied from the suction nozzle 7 to the LED chip 1 for a predetermined time while maintaining this contact state. By applying this ultrasonic vibration, the tip surfaces of the respective bumps 5 that are pressed against each other and are in contact with each other are adhered to each other to be in a metal-bonded state.

  By performing the metal bonding in this way, each pad 2 of the LED chip 1 is bonded to each substrate electrode 4 of the substrate 3 via each bump 5 and each bonding electrode 16. Become. Thereafter, the suction holding of the LED chip 1 by the suction nozzle 7 is released, and the suction nozzle 7 is raised. As a result, the LED chip 1 is mounted on the substrate 3 as shown in FIG. 5E.

  According to the second embodiment, as in the first embodiment, the tip height position of each bump 5 resulting from the difference in formation height between the P-pole pad 2p and the N-pole pad 2n in the LED chip 1 Even if the formation thickness of each bonding electrode 6 is not varied according to the difference, each bonding electrode 16 is formed of a gold nano paste that is a paste-like conductive material. By utilizing the characteristic of being soft (softer than the bumps 5 and the like), the bumps 5 are pressed and deformed by the bumps 5 in accordance with the formation heights of the bumps 5, so that the bumps 5 can be deformed. The difference in the tip height position can be absorbed.

  Therefore, even if there is a difference in the formation height of each pad 2 and the formation height of each bump 5 in this way, the bonding electrode 16 can be deformed to ensure contact. . In addition, by applying ultrasonic vibration in such a state of being reliably in contact with each other, each bump 5 and each bonding electrode 16 can be reliably metal-bonded, and ultrasonic vibration is applied. As a result, the LED chip 1 can be reliably mounted on the substrate 3.

  Further, according to such a mounting method, the LED chip 1 is not limited to the case where it is known in advance that the formation heights of the P-electrode pad 2p and the N-electrode pad 2n are different from each other. It can also be applied to the case where the formation height of the pads and bumps varies depending on the formation accuracy, and can be said to be a more versatile mounting method.

(Third embodiment)
The mounting method of the LED chip 1 which is an example of the mounting method of the semiconductor element concerning the 3rd Embodiment of this invention is demonstrated using the schematic explanatory drawing shown to FIG. 8A, FIG. 8B, and FIG. 8C. In addition, the same reference number is attached | subjected about the same component which the LED chip 1 and the board | substrate 3 in the said 1st Embodiment have for the purpose of making an understanding of the description easy.

  In the mounting method of the third embodiment, bumps are formed by plating on the respective pads 2 of the LED chip 1 as in the mounting methods of the first embodiment and the second embodiment. The LED chip 1 is not mounted on the substrate 3 with each bump interposed, but is mounted without forming each bump.

  First, as shown in FIG. 8A, the gold nano paste is supplied onto the upper surface of each substrate electrode 4 of the substrate 3 by means of coating or printing to form each bonding electrode 26. At this time, similarly to the mounting method in the first embodiment, the thickness dimension of each bonding electrode 26 varies according to the difference in formation height between the P-electrode pad 2p and the N-electrode pad 2n of the LED chip 1. In addition, each bonding electrode 26 is formed while finely adjusting the supply amount of the gold nano paste. In the formation of each of the bonding electrodes 26, the formed shape is stabilized by applying predetermined energy to the supplied gold nano paste.

  Thereafter, as shown in FIG. 8A, the surface of each LED chip 1 on which the pads 2 are not formed is sucked and held by the suction nozzle 7 and placed above the substrate 3. Each pad 2 and each substrate electrode 4 of the substrate 3 are aligned in the direction along the surface of the substrate 3 so that they can be bonded to each other.

  After this alignment, the suction nozzle 7 is lowered and the LED chip 1 is lowered so that the respective pads 2 of the LED chip 1 are brought into contact with the respective bonding electrodes 26. At this time, although the formation heights of the respective pads 2 in the LED chip 1 are different, the respective junction electrodes 26 are formed on the substrate 3 in accordance with the difference, so that the junction electrode 26 of the P-electrode pad 2p. And the contact of the N-pole pad 2n with the bonding electrode 26 are performed substantially simultaneously. The lowering operation of the suction nozzle 7 is stopped while maintaining this contact state. In this state, each bonding electrode 26 is kept in contact with and pressed against each pad 2.

  Thereafter, as shown in FIG. 8B, ultrasonic vibration is applied from the suction nozzle 7 to the LED chip 1 for a predetermined time while maintaining this contact state. By applying the ultrasonic vibration, the surface of each pad 2 that is pressed against each other and the upper surface of each bonding electrode 26 are adhered to each other to be in a metal-bonded state.

  By performing metal bonding in this manner, each pad 2 of the LED chip 1 is bonded to each substrate electrode 4 of the substrate 3 via each bonding electrode 26. Thereafter, the suction holding of the LED chip 1 by the suction nozzle 7 is released, and the suction nozzle 7 is raised. As a result, the LED chip 1 is mounted on the substrate 3 as shown in FIG. 8C.

  In the above description, the case where such a bonding electrode 26 is formed on each substrate electrode 4 of the substrate 3 has been described. However, instead of such a case, the bonding electrode 26 is formed on each pad 2 of the LED chip 1. It may be a case where the bonding electrode 26 is formed. In any case, each pad 2 and the substrate electrode 4 can be brought into contact with each other via the respective bonding electrodes 26.

  According to the third embodiment, plating is performed on each pad 2 of the LED chip 1 or on each substrate electrode 3 of the substrate 3 as in the mounting method in the first embodiment and the second embodiment. Unlike the case where each bump 5 is formed by a method or the like, each pad 2 and each substrate electrode 4 are brought into contact with each other via the respective bonding electrodes 26 without forming each bump. In this state, by applying ultrasonic vibration, it is possible to perform bonding with the bonding electrode 26 between each pad 2 and the substrate electrode 4 interposed.

  Since such a mounting method does not involve a bump formation step by plating, the time and labor required for the step can be eliminated, and a more efficient mounting method can be provided.

  Here, a schematic explanatory view showing a conventional ultrasonic bonding method shown in FIG. 9 is used for general conditions required in bonding (ultrasonic bonding) in application of ultrasonic vibration performed in each of the above embodiments. I will explain.

  In the conventional ultrasonic bonding method shown in FIG. 9, each bump 505 formed on each element electrode 502 in the semiconductor element 510 sucked and held by the suction nozzle 510 is formed on each substrate electrode 504 of the substrate 503. In addition, ultrasonic bonding is performed by applying ultrasonic vibration from the suction nozzle 510 in a state of being in contact while being pressed with a bonding load F that is a predetermined vertical load. At this time, the friction coefficient between the holding surface of the semiconductor element 510 of the suction nozzle 510 and the upper surface of the semiconductor element 501 in the drawing is μ1, and the friction coefficient between the bump 505 and the substrate electrode 504 in contact with each other is μ2. And the friction coefficient between the substrate 503 and the stage 520 on which the substrate 503 is held is μ3.

  In such ultrasonic bonding, in order to perform ideal ultrasonic bonding, it is desirable to ensure the condition of (μ3F> μ1F> μ2F). That is, it is preferable that the ultrasonic vibration is effectively transmitted to the contact portion between each bump 505 and the substrate electrode 504 by the application of the ultrasonic vibration by the suction nozzle 510. It is not preferable that ultrasonic vibration is positively transmitted between the element 501 and between the substrate 3 and the stage 520. For example, under the condition of (μ2F> μ1F), the ultrasonic vibration is more positive between the holding surface of the suction nozzle 510 and the semiconductor element 501 than the contact portion between each bump 505 and the substrate electrode 504. Will be granted. In such a case, a side slip occurs between the suction nozzle 510 and the semiconductor element 501, and there may be a case where ultrasonic bonding itself cannot be performed.

  On the other hand, in the mounting method according to each embodiment of the present invention, predetermined energy is applied between each pad 2 of the LED chip 1 and each substrate electrode 4 of the substrate 3. Since ultrasonic vibration is applied in the state where the bonding electrode formed of the stabilized gold nano paste is interposed, the ultrasonic vibration is positively applied to each bonding electrode which is the softest part. Can concentrate. Therefore, it is possible to perform more effective bonding in which the time required for ultrasonic bonding is shortened. Therefore, it is possible to provide a joining method by applying ultrasonic vibration that can prevent the occurrence of side slipping of the suction nozzle and damage to the LED chip or the bump.

  In each of the above embodiments, gold nano paste is supplied to each pad 2 of each LED chip 1, each bump 5, or each substrate electrode 4 of the substrate 3 to require each bonding electrode. Although the case where it is formed at the position where it is formed has been described, the present invention is not limited only to such a case. Instead of such a case, for example, by using a gold nanopaste and an insulating material in advance, a sheet in which a bonding electrode formed of a gold nanopaste is disposed in an insulating sheet is formed. The bonding electrode formed on the LED chip 1 is aligned with the pad 2 of the LED chip 1 and the substrate electrode 4 of the substrate 3, and then the pad 2 of the LED chip 1 and the substrate electrode 4 of the substrate 3 are placed in the sheet. It may be a case where the contact electrode is interposed and contacted. By applying ultrasonic vibration in the contacted state, the pad 2 and the substrate electrode 4 can be bonded with the bonding electrode in the sheet interposed. At the same time, a sealing process for sealing the periphery of the joint portion with the insulating material in the sheet can be performed.

  In each of the above embodiments, the case where the semiconductor element is the LED chip 1 has been mainly described. However, the semiconductor element is not limited to such a case. Needless to say, the mounting method of the present invention can be applied regardless of the function or the like of the semiconductor element as long as the semiconductor element is mounted on the substrate via the element electrode. In addition, even if a plurality of element electrodes formed in such a semiconductor element are formed or only one element electrode is formed, the mounting method of the present invention is used. Can be applied.

  Here, as an example of the actual mounting state of the LED chip on the substrate, FIG. 14 shows an enlarged cross-sectional view of the joint portion in a state where the LED chip 1 is mounted on the substrate 3. As shown in FIG. 14, bumps 5 are formed on the pads 2 of the LED chip 1, and electrode wirings 36 formed of gold nano paste are formed on the substrate 3. By applying ultrasonic vibration in a state where the lower end of the bump 5 is in contact with the electrode wiring, the surface of the lower end of the bump 5 and the surface of the electrode wiring 36 in contact with the surface are metal-bonded. Thus, the above implementation is performed. The bump 5 is formed with a size of 50 μm × 50 μm.

  In the above embodiment, the case where ultrasonic bonding is performed by applying ultrasonic vibration to each bonding electrode 6 formed of gold nano paste has been described. The joining method using the electrode 6 is not limited to such a case. Instead of such a case, for example, without applying ultrasonic vibration, each bonding electrode 6 is pressed so as to be sandwiched between each pad 2 and substrate electrode 4 to deform its shape, The bonding may be performed by bringing the pad 2 and each substrate electrode 4 into contact with each other with the bonding electrodes 6 interposed therebetween. In addition, after such contact | abutting, each joining electrode 6 may be heated, and it may be the case where it joins by carrying out cooling hardening after that, and each joining electrode 6 may be left unattended. In such a case, the bonding may be performed by naturally curing.

  It is to be noted that, by appropriately combining arbitrary embodiments of the various embodiments described above, the effects possessed by them can be produced.

  Although the present invention has been fully described in connection with preferred embodiments with reference to the accompanying drawings, various variations and modifications will be apparent to those skilled in the art. Such changes and modifications are to be understood as being included therein, so long as they do not depart from the scope of the present invention according to the appended claims.

It is a schematic plan view which shows the structure of the LED chip used with the mounting method concerning 1st Embodiment of this invention. It is a schematic cross section which shows the structure of the LED chip of FIG. It is a schematic cross section of the LED chip of FIG. It is a schematic cross section of the board | substrate with which an LED chip is mounted. It is a schematic explanatory drawing which shows the procedure of the mounting method of the LED chip concerning the said 1st Embodiment, (A) is a schematic cross section of the LED chip in the state in which bump was formed, (B) is a bonding electrode formation (C) is a schematic enlarged cross-sectional view of a bonding electrode formed of gold nano paste, (D) is a state in which the LED chip and the substrate are aligned, (E) shows a state in which ultrasonic vibration is applied to the LED chip and the substrate in contact with each other, and (F) shows a state in which a sealing process has been performed. It is a schematic explanatory drawing which shows the procedure of the mounting method of the LED chip concerning 2nd Embodiment of this invention, and is a schematic cross section of the LED chip in the state in which bump was formed. It is a schematic explanatory drawing which shows the procedure of the mounting method of the LED chip concerning 2nd Embodiment of this invention, and is a schematic cross section of the board | substrate in the state in which the joining electrode was formed. It is a schematic explanatory drawing which shows the procedure of the mounting method of the LED chip concerning 2nd Embodiment of this invention, and is a figure of the state in which the LED chip and the board | substrate were aligned. It is a schematic explanatory drawing which shows the procedure of the mounting method of the LED chip concerning 2nd Embodiment of this invention, and is a figure of the state by which the ultrasonic vibration is provided to the LED chip and board | substrate which are mutually contacted, and mounting It is a figure of a completion state. It is a schematic explanatory drawing which shows the procedure of the mounting method of the LED chip concerning 2nd Embodiment of this invention, and is a figure of a mounting completion state. It is a model expanded sectional view of the joining electrode used in the mounting method of the LED chip concerning the modification of the said 1st Embodiment. It is a schematic cross section which shows the mounting method of the LED chip concerning the modification of the said 1st Embodiment, and has shown the state by which the joining electrode is formed on the bump of an LED chip. It is a schematic explanatory drawing which shows the procedure of the mounting method of the LED chip concerning 3rd Embodiment of this invention, and is a figure of the state with which the LED chip and board | substrate with which bump was not formed were aligned. It is a schematic explanatory drawing which shows the procedure of the mounting method of the LED chip concerning 3rd Embodiment of this invention, and is a figure of the state by which the ultrasonic vibration is provided to the LED chip and board | substrate which are in contact with each other. It is a schematic explanatory drawing which shows the procedure of the mounting method of the LED chip concerning 3rd Embodiment of this invention, and is a figure of the state to which the sealing process was performed. It is a schematic explanatory drawing which shows the relationship between the bonding load and the friction coefficient in the conventional semiconductor element mounting method by applying ultrasonic vibration. It is a schematic explanatory drawing which shows the mounting method of the conventional semiconductor element, and is a figure of the state with which the semiconductor element and the board | substrate were aligned. It is a schematic explanatory drawing which shows the mounting method of the conventional semiconductor element, and is a figure of the state in which the ultrasonic vibration is provided to the semiconductor element and board | substrate which are mutually contact | abutting. It is a schematic explanatory drawing which further shows the mounting method of the conventional semiconductor element, and is a figure in a state where application of ultrasonic vibration is started. It is a schematic explanatory drawing which further shows the mounting method of the conventional semiconductor element, and is a figure of the state which diffusion of an element electrode and a bump is advancing. It is a schematic explanatory drawing which further shows the mounting method of the conventional semiconductor element, and is a figure of the state which has generated the crack in an alloy layer. FIG. 10 is a schematic explanatory view showing another conventional method for mounting a semiconductor element, and shows a state in which each bump height formed on the semiconductor element varies. FIG. 10 is a schematic explanatory view showing still another conventional method for mounting a semiconductor element, in a state where ultrasonic vibration is applied in a state where only one bump is in contact. FIG. 10 is a schematic explanatory view showing another conventional method for mounting a semiconductor element, in which the bonding of one bump is completed but the bonding is performed to the other bump. It is a flowchart which shows the formation process of the gold bump by the plating method in the mounting method of the conventional semiconductor element. It is an expanded sectional view of the mounting state to the board | substrate of the LED chip concerning the Example of this invention. It is a schematic explanatory drawing which shows the procedure of the mounting method of the LED chip concerning the modification of the said 1st Embodiment, and is a figure of the state by which bump was formed in the board | substrate and alignment with the LED chip and the said board | substrate was performed. . It is a schematic explanatory drawing which shows the procedure of the mounting method of the LED chip concerning the modification of the said 1st Embodiment, and is a figure of the state by which the ultrasonic vibration is provided to the LED chip and board | substrate in a mutually contact state. It is a schematic explanatory drawing which shows the procedure of the mounting method of the LED chip concerning the modification of the said 1st Embodiment, bump was formed in both LED chip and a board | substrate, and the alignment with the said LED chip and a board | substrate was performed It is a figure of a state. It is a schematic explanatory drawing which shows the procedure of the mounting method of the LED chip concerning the modification of the said 1st Embodiment, and is a figure of the state by which the ultrasonic vibration is provided to the LED chip and board | substrate in a mutually contact state. It is a schematic cross section of the mechanism of the stabilization process of gold nano paste, and is a diagram showing a dispersion state at room temperature. It is a schematic cross section of the mechanism of stabilization processing of gold nano paste, and is a diagram showing a state in which energy application is started. It is a schematic cross section of the mechanism of the stabilization process of gold nano paste, and is a diagram showing a state where the fusion of gold nanoparticles has started. It is a schematic cross section of the mechanism of the stabilization process of gold nano paste, and is a view showing a state where fusion is completed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 LED chip 2 Pad 2p P pole pad 2n N pole pad 3 Substrate 4 Substrate electrode 5 Bump 6 Bonding electrode 7 Adsorption nozzle 8 Sealing member 10 LED chip mounting substrate

Claims (19)

In a method for mounting a semiconductor element, a semiconductor element having an element electrode that can be bonded to a substrate electrode included in the substrate is mounted on the substrate by bonding the substrate electrode and the element electrode.
A bonding member formed of a paste-like conductive material is disposed between the element electrode and the substrate electrode, and the element electrode and the substrate electrode are brought into contact with each other with the bonding member interposed therebetween,
A method for mounting a semiconductor element, in which the bonding member, the substrate electrode, and the element electrode are bonded to each other by applying ultrasonic vibration to the bonding member and the element electrode or the substrate electrode in the contact state. In a semiconductor element mounting method, a semiconductor element having a plurality of element electrodes that can be bonded to each substrate electrode of a substrate is mounted on the substrate by bonding each of the substrate electrodes and each of the element electrodes. ,
A bonding member formed of a paste-like conductive material is disposed between each element electrode and each substrate electrode, and each element electrode and each substrate electrode are bonded to each other. Abutting through the members,
In the contact state, by applying ultrasonic vibration to the respective bonding members and the respective element electrodes or the substrate electrodes, the respective bonding members, the respective substrate electrodes, and the respective element electrodes, A method for mounting a semiconductor element that joins. Supplying the paste-like conductive material to the respective substrate electrodes or the respective element electrodes by coating or printing,
Each of the joining members is formed by applying energy to the supplied paste-like conductive material,
The method for mounting a semiconductor element according to claim 2, wherein each of the element electrodes and each of the substrate electrodes are brought into contact with each other with the bonding members interposed therebetween. After supplying the paste-like conductive material, by applying the energy, the shape formed by the paste-like conductive material is stabilized, and the respective joining members are formed. A method for mounting a semiconductor device according to claim 3. The semiconductor element according to claim 3 or 4, wherein the paste-like conductive material is a gold nanopaste, and the bonding material is a metal film generated by applying the energy to the gold nanopaste. Implementation method. While interposing each of the bonding members, the respective element electrodes are pressed relatively to the respective substrate electrodes, and the respective bonding members are deformed, whereby each of the element electrodes and each of the respective electrode members are deformed. 6. The method of mounting a semiconductor element according to claim 3, wherein the contact with the substrate electrode is performed by interposing the respective joining members. The semiconductor element mounting method according to claim 3, wherein a plurality of the joining members are formed on each of the substrate electrodes or each of the element electrodes. The application of the ultrasonic vibration to each of the bonding members is such that the held surface, which is the surface opposite to the formation surface of each of the element electrodes in the semiconductor element, is held by the holding surface of the component holding member. The method for mounting a semiconductor element according to claim 3, wherein the ultrasonic vibration is applied through the semiconductor element by the component holding member in a state. The semiconductor element has a P-type electrode and an N-type electrode having different thickness dimensions as the respective element electrodes,
Depending on the difference in distance between each element electrode and each substrate electrode due to the difference in thickness between the P-type electrode and the N-type electrode, the thickness dimension of each of the bonding members is The method for mounting a semiconductor element according to claim 3, wherein the respective joining members are formed differently. The semiconductor element has a plurality of protruding electrodes formed on the respective element electrodes,
While supplying the paste-like conductive material to each of the protruding electrodes or each of the substrate electrodes, and applying energy to the paste-like conductive material, the respective bonding members are formed,
3. The method of mounting a semiconductor element according to claim 2, wherein each of the element electrodes and each of the substrate electrodes are brought into contact with each of the bonding members and the protruding electrodes. The method of mounting a semiconductor element according to claim 10, wherein each of the protruding electrodes is formed using a conductive material by a plating method. The semiconductor element has, as the respective element electrodes, a P-pole electrode and an N-pole electrode having different thickness dimensions,
Depending on the difference in distance between the tip of each protruding electrode and each substrate electrode caused by the difference in the height of the tip of each protruding electrode based on the difference in thickness of each element electrode The method of mounting a semiconductor element according to claim 10 or 11, wherein the respective joining members are supplied so that the thickness dimensions of the respective joining members are different. The substrate has a plurality of protruding electrodes formed on the respective substrate electrodes,
While supplying the paste-like conductive material to each of the protruding electrodes or each of the element electrodes, and applying energy to the paste-like conductive material, the respective bonding members are formed,
3. The method of mounting a semiconductor element according to claim 2, wherein each of the element electrodes and each of the substrate electrodes are brought into contact with each of the bonding members and the protruding electrodes. The semiconductor element has, as the respective element electrodes, a P-pole electrode and an N-pole electrode having different thickness dimensions,
Depending on the difference in the distance between the respective element electrodes and the tips of the respective protruding electrodes caused by the difference in the thickness of the respective element electrodes, the thickness of the respective bonding members may be different. 14. The method of mounting a semiconductor element according to claim 13, wherein the respective joining members are supplied. Before the contact of the respective element electrodes of the semiconductor element and the respective substrate electrodes of the substrate with the respective joining members interposed therebetween, the respective substrate electrodes on the substrate are The method for mounting a semiconductor element according to claim 3, wherein a plasma cleaning process is performed. Claims: After the joining of the respective element electrodes of the semiconductor element and the respective substrate electrodes of the substrate with the respective joining members interposed therebetween, the periphery of the joined portions is sealed with an insulating material. Item 16. A method for mounting a semiconductor element according to any one of Items 3 to 15. The semiconductor element is an LED element, and each of the bonding members has a function of transferring heat generated by applying voltage to the LED element to the substrate side. The mounting method of the semiconductor element as described in one. A substrate having a plurality of substrate electrodes;
A semiconductor element having a plurality of element electrodes electrically connectable to the respective substrate electrodes;
A plurality of bonding members disposed between each of the substrate electrodes and each of the element electrodes and formed into a metal film by applying energy to the gold nanopaste;
The respective bonding members are bonded to the respective substrate electrodes or the respective element electrodes by adhesion, so that the respective substrate electrodes and the respective element electrodes are interposed with the respective bonding members. A semiconductor element mounting substrate, wherein the semiconductor element is mounted on the substrate by bonding. In a semiconductor element mounting method for mounting a semiconductor element having a plurality of element electrodes on a substrate having a plurality of substrate electrodes,
A bonding member formed by applying energy to a paste-like conductive material is disposed between each of the element electrodes and each of the substrate electrodes, and each of the element electrodes and each of the substrates is disposed. Each of the element electrodes is deformed by pressing the respective element electrodes relative to the respective substrate electrodes while interposing the respective bonding members with the electrodes, and deforming the respective bonding members. A method of mounting a semiconductor element, wherein each of the substrate electrodes is brought into contact with each of the bonding members.

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