KR20180123452A - Bonding material and manufacturing method thereof - Google Patents

Abstract

Provided is a semiconductor element mounting member capable of a low-temperature and low-pressure mounting process while using a low-cost material and a manufacturing method thereof. The semiconductor element mounting member according to the present invention comprises: a first layer including a metal film; and a second layer formed on at least one side of the first layer, and including at least one of a metal particle, a metal oxide particle and a composite metal particle including a metal oxide layer on a surface of the composite metal particle.

Description

Technical Field [0001] The present invention relates to a semiconductor device mounting material,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a semiconductor element mounting material and a manufacturing method thereof, and more particularly, to a semiconductor element mounting material and a manufacturing method capable of performing a low temperature and low pressure mounting process while using a low cost material.

Power modules are key components in the core power systems and solar cell smart power systems of next-generation automobiles, such as electric vehicles. Power semi-conductor or power device modules for power conversion include insulated gate bipolar mode transistors (IGBTs), metal oxide semiconductor field effect transistors (MOSFETs) or intelligent power modules (IPMs).

In the case of electric power modules provided in electronic products, electric vehicles, or solar cell power systems, fuel efficiency improvement and smartization have become important in the case of large power modules as well, due to the tendency of downsizing and high density of recent electronic devices . In order to maximize the power conversion efficiency, GaN and SiC devices have been used in recent years as well as Si devices. When power is converted using such a power conversion device, high voltage and high current flow for a long time and a large amount of heat is generated. Therefore, the joining technique, which is most important in the fabrication of such a power conversion module, is a technique that can maintain high reliability even when it is used at a high temperature for a long time.

Generally, a power semiconductor chip is mounted on a substrate through a sintering reaction in which a silver paste (Ag) powder is mixed with a paste to place it on a substrate, and a mutual diffusion of silver powder is induced at a high temperature. However, it has been pointed out that the silver material is expensive, the manufacturing cost is increased due to the high temperature and high pressure process, and the reliability of the mounting site after sintering has been pointed out. Therefore, it is required to secure a low-cost and efficient mounting process as a mounting technique with high reliability while maintaining the same characteristics as the thermal conductivity of the junction portion in chip mounting.

It is an object of the present invention to provide a semiconductor element mounting material and a manufacturing method which can perform a low temperature and low pressure mounting process while using a low cost material.

According to an aspect of the present invention, there is provided a semiconductor device mounting material for mounting a semiconductor device on a substrate, comprising: a first layer including a metal film; And a second layer formed on at least one side of the first layer, the second layer comprising metal particles, metal oxide particles and composite metal particles comprising a metal oxide layer on the surface.

The second layer may be formed of only particles.

Particles may be located within the first layer, and the remaining portion may be located outside the first layer.

When any one of the particles is referred to as a first particle and the other particle is referred to as a second particle, the first particle and the second particle may be located apart from each other.

The metal oxide particles and the metal oxide layer may contain an oxide of any one of Cu, Ni, Ag, Ti, Al and Zn.

According to another aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: preparing a first layer including a metal film; And forming a second layer by coating at least one of particles of metal particles, metal oxide particles, and composite metal particles on the surface of the first layer with a metal oxide layer on one surface of the first layer, There is provided a method for manufacturing a semiconductor element mounting material.

The step of forming the second layer may be a step of embedding a part of at least one particle of the metal particles, the metal oxide particles and the composite metal particles including the metal oxide layer on the surface into the first layer.

The step of forming the second layer includes the step of applying at least one of the metal particles, the metal oxide particles, and the composite metal particles including the metal oxide layer on the surface to the first layer using a spraying method or a rolling method Or the step of forming the second layer can be performed by using a printing method or a doctor blade to form a paste containing at least one particle of metal particles, metal oxide particles and composite metal particles including a metal oxide layer on the surface Applying to the first layer and drying.

According to another aspect of the present invention, And a device mounted on the substrate, the device comprising: a first layer comprising a metal film, the first layer being formed on at least one side of the first layer, the first layer comprising metal particles, metal oxide particles and a metal oxide layer And a second layer comprising at least one of the particles of the composite metal particles, wherein the second layer includes a plurality of particles of the composite metal particles, and is mounted on the substrate by sintering the semiconductor element mounting material .

According to another aspect of the present invention, there is provided a method for manufacturing a composite metal particle, comprising the steps of: forming a first layer including a metal film on a substrate; and a second metal layer formed on at least one surface of the first layer, A semiconductor element mounting reformation step of forming a semiconductor element mounting material including a second layer including at least one particle; Positioning an element on a semiconductor element mounting material; And sintering the semiconductor element mounting material.

Here, the step of sintering may further include a step of reducing at least one of the metal particles, the metal oxide particles, and the composite metal particles including the metal oxide layer on the surface thereof.

According to the present invention, it is possible to realize a highly reliable mounting portion junction characteristic by using a low-cost material, and there is an effect that a device package can be realized at the lower end in manufacturing.

In addition, since the mounting process can be performed at a lower temperature and a lower pressure than in the conventional mounting process, a low-cost process can be realized.

In addition, the heat conductive property of the mounting material is excellent, and excellent heat dissipation characteristics can be exhibited when a power device such as an IGBT or a MOSFET used in an EV / HEV, a solar power, a power conversion module for wind power generation, and an LED is mounted and bonded.

1 is a cross-sectional view of a semiconductor element mounting material according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of a semiconductor element mounting material according to another embodiment of the present invention, FIG. 3 is a cross-sectional view of a semiconductor element mounting material according to still another embodiment of the present invention, Sectional view of the element mounting material.
FIG. 5 is an enlarged view of a semiconductor element mounting material according to still another embodiment of the present invention, and FIG. 6 is an enlarged view of a semiconductor element mounting material according to still another embodiment of the present invention.
7 is a cross-sectional view of a semiconductor device package according to another embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. The embodiments of the present invention are provided to enable those skilled in the art to more fully understand the present invention. It should be understood that while the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, The present invention is not limited thereto.

FIG. 1 is a cross-sectional view of a semiconductor element mounting material according to one embodiment of the present invention, and FIGS. 2, 3, and 4 are cross-sectional views of a semiconductor element mounting material according to another embodiment of the present invention, respectively. A semiconductor element mounting material (100) according to the present invention comprises a first layer (110) comprising a metal film; And a second layer (120) formed on at least one side of the first layer (110), the composite layer comprising at least one of metal particles, metal oxide particles and composite metal particles comprising a metal oxide layer on the surface . The semiconductor element mounting material 100 may further include a third layer including at least one of metal particles, metal oxide particles, and metal oxide layers formed on the other surface of the first layer 110, The second layer 120 may be in contact with the semiconductor device, and the third layer 130 may be in contact with the substrate. Hereinafter, the semiconductor element mounting material for mounting the semiconductor element on the substrate will be referred to as a semiconductor element mounting material.

The first layer 110 of the semiconductor element mounting material 100 according to the present invention includes a metal film. Since the first layer 110 includes a metal film, the heat dissipation property can be superior to that of a paste-type bonded material including an organic material or the like. Further, in the case of a metal film, it is possible to form the metal film with a certain thickness, thereby ensuring the uniformity of the bonding thickness, which is particularly advantageous in the case of a large area semiconductor device.

As the metal film that can be used for the first layer 110, any metal that can be formed into a thin film can be used. For example, the metal film may be a thin film of any one of Cu, Ni, Ag, Ti, Al and Zn.

A second layer 120 is formed on at least one surface of the first layer 110 and a third layer 130 is formed on the other surface. The second layer 120 and the third layer 130 are positioned between the element and the substrate in the element mounting process and serve to bond the element to the substrate. The second layer 120 and the third layer 130 may comprise composite metal particles comprising metal particles, metal oxide particles and a metal oxide layer on the surface. The second layer 120 and the third layer 130 may be sintered at a predetermined temperature and a predetermined pressure when mounting the semiconductor element on the substrate including such particles to exhibit bonding properties with the element and the substrate.

The second layer 120 includes at least one of metal particles, metal oxide particles, and composite metal particles including a metal oxide on the surface thereof. The composite metal particles include metal particles, metal oxide particles and a metal oxide layer on the surface thereof. The metal may be any one of Cu, Ni, Ag, Ti, Al and Zn. That is, the metal oxide particles and the metal oxide layer may include an oxide of any one of Cu, Ni, Ag, Ti, Al and Zn. For example, when the metal is copper, the metal oxide particles and the metal oxide layer may comprise copper oxide. Copper oxides include Cu ₂ O and CuO.

The metal particles, the metal oxide particles, and the composite metal particles containing the metal oxide on the surface may have a particle size of micro or nano size, and the shape may be spherical or flake type. Hereinafter, metal particles, metal oxide particles, and composite metal particles containing a metal oxide on the surface will be referred to as "particles".

Referring to FIG. 2, a second layer 120 is formed on an upper surface of the first layer 110, and the second layer 120 is formed only of particles. In other words, the second layer 120 may be formed of only particles, not including a material other than particles such as a solvent or a binder. The second layer formed only of such particles has no impurities and is excellent in heat radiation characteristics.

3, when the particles of the second layer 120 are formed on the upper surface of the first layer 110, a part of the particles is located inside the first layer 110, Can be located. That is, the particles may be positioned in a partially embedded state in the first layer 110. When the particles are embedded in the first layer 110, reliability of the bonding layer formed of the particles is improved, and the volume of the bonding layer is minimized, thereby minimizing the defective bonding process such as voids that may occur in the bonding layer .

In addition, the particles of the second layer 120 are shown as being spaced apart from one another in Figures 2 and 3. That is, when any one of the particles is referred to as a first particle and the other particle is referred to as a second particle, the first particle and the second particle are located apart from each other. The particles of the second layer 120 may be placed in contact with each other, the two or more particle layers may be formed, and the particles may be positioned apart from each other as shown in FIGS. As shown in FIGS. 2 and 3, even when the particles are not in contact with each other but are spaced apart from each other, they can be connected to each other due to sintering in a subsequent mounting process, so that device mounting is possible. When the particles are spaced apart, the amount of particles used is minimized, and the volume of the bonding layer is also minimized, so that the defective bonding process as described above can be minimized.

FIG. 5 is an enlarged view of a semiconductor element mounting material according to still another embodiment of the present invention, and FIG. 6 is an enlarged view of a semiconductor element mounting material according to still another embodiment of the present invention. 5 illustrates a state where the second layer 120 includes the composite metal particles 140 and FIG. 6 illustrates a state where the composite metal particles 140 are embedded in the first layer 110. FIG. . The composite metal particles 140 have a metal oxide layer 141 formed on its surface. The inner core 142 of the composite metal particles 140 is not particularly limited as the formation of the bonding layer of the second layer 120 may be formed by the metal oxide layer 141. However, .

The composite metal particles 140 can be obtained by oxidizing the surface of the metal particles. When the core 142 is a metal, the metal of the metal oxide layer 141 may be the same metal as the metal of the core 142, but may be a different metal. The metal oxide of the metal oxide layer 141 may be reduced due to a reducing material when the device is mounted and converted into a metal layer. For example, if the second layer 120 comprises only metal particles, it is possible to oxidize during the process due to the nature of the metal particles. For example, when the second layer 120 contains copper particles, the copper particles can be naturally oxidized in the process, and can be oxidized during sintering when heat-sintering for the mounting of copper particles. As a result, the bonded region between the device and the substrate is oxidized after the semiconductor device is mounted, so that the reliability of bonding is lowered and physical properties including thermal conductivity may be deteriorated.

However, when the metal oxide layer is first formed on the surface of the metal particles to obtain the composite metal particles 140 and used for device mounting, as in this embodiment, the metal oxide layer formed on the surface during the device mounting process, Oxidation of the final bonding layer is prevented from occurring at the contact surface of the final bonding layer.

The composite metal particles 140 may include the metal 142, although the core 142 includes the metal. When the pure metal content is lowered, the material cost can be reduced, and since the metal oxide included in the core 142 is also reduced together with the subsequent reduction process, metallic material is obtained after the packaging.

In the case of using the composite metal particles 140 in a state of being embedded in the first layer 110 in a semiconductor device, the reduction area is reduced, which is advantageous in terms of reduction time and process. That is, referring to FIG. 6, the composite metal particles 140 do not require reduction of the metal oxide layer located inside the first layer 110, shortening the reduction time, and simplifying the reduction process. The metal oxide layer in the first layer 110 is reduced by reducing the region exposed to the outside of the first layer 110 and forming the bonding layer by sintering the reduced metal, The bonding layer can be formed and the semiconductor element can be mounted.

According to another aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: preparing a first layer including a metal film; And forming a second layer by coating at least one of particles of metal particles, metal oxide particles, and composite metal particles on the surface of the first layer with a metal oxide layer on one surface of the first layer, There is provided a method for manufacturing a semiconductor element mounting material.

The step of forming the second layer on the first layer may include forming at least one of the metal particles, the metal oxide particles, and the composite metal particles including the metal oxide layer on the surface thereof by a spraying method or a rolling method, As shown in FIG. That is, the second layer can be formed by coating the particles in the first layer mechanically to form only the particles.

Alternatively, a paste containing at least one particle of metal particles, metal oxide particles and metal oxide layers on the surface thereof is applied to the first layer and dried using a printing method or a doctor blade to form a first layer A second layer containing only particles can be formed. Upon forming the paste, a solvent or a binder may be mixed with the particles. Examples of the solvent that can be used include a hydrocarbon solvent, a chlorinated hydrocarbon solvent, a cyclic ether solvent, a ketone solvent, an alcohol solvent, a polyhydric alcohol solvent, an acetate solvent, an ether solvent of a polyhydric alcohol or a terpene solvent .

Examples of the binder that can be used in the present embodiment include a cellulose resin, a polyvinyl chloride resin, a copolymer resin, a polyvinyl alcohol resin, a polyvinyl pyrrolidone resin, an acrylic resin, a vinyl acetate-acrylate copolymer resin, A resin, an alkyd resin, an epoxy resin, a phenol resin, a rosin ester resin, a polyester resin, or silicone.

At this time, in the case of the spray method or the rolling method, the particles constituting the second layer can be formed so as to be embedded in the first layer by increasing the spray strength or applying pressure to the roller. In the case of using a printing method or a doctor blade, pressure can be applied to cause particles in the paste to be embedded into the first layer.

7 is a cross-sectional view of a semiconductor device package according to another embodiment of the present invention. A semiconductor device package 1000 according to the present embodiment includes a substrate 300; And a semiconductor device 200 mounted on the substrate 300. The semiconductor device 200 includes a first layer including a metal film and a second layer formed on at least one side of the first layer, And a second layer comprising at least one particle of metal particles, metal oxide particles, and composite metal particles comprising a metal oxide layer on the surface, wherein the semiconductor element mounting material (100) (100).

As the substrate 300 that can be used in the semiconductor device package 1000 of the present invention, a synthetic resin substrate selected from polyimide, polyurethane, PMMA, and PET, a metal substrate selected from stainless steel, aluminum, Tin Oxide) and a non-metallic substrate selected from ceramics such as Al ₂ O ₃ , AlN, or Si ₃ N ₄ , glass, and silicon. The substrate 300 can be any substrate that is heat resistant to the sintering temperature of the semiconductor element mounting material 100.

Examples of the device 200 that can be mounted on the substrate 300 include a diode, an IC, and a power device such as an IGBT, a MOSFET, and the like. Particularly, the device that can be used in the present invention is a power device such as an IGBT or a MOSFET used in an EV / HEV, a solar power, a power conversion module for a wind power generation, an LED, etc. However, according to the high thermal conductivity of the semiconductor device mounting material according to the present invention This is because the heat dissipation characteristics are excellent at the joint surface.

A semiconductor element mounting method according to the present invention is a method for mounting a semiconductor element comprising a first layer including a metal film on a substrate and a second metal layer formed on at least one side of the first layer and including metal particles, A semiconductor element mounting reformation step of forming a semiconductor element mounting material including a second layer including at least one particle; Positioning an element on a semiconductor element mounting material; And sintering the semiconductor element mounting material.

The semiconductor element mounting material 100 is placed on the substrate 300 and the device 200 is placed on the upper surface of the semiconductor device mounting material 100 and then the sintering process is performed. The sintering process can be performed simultaneously with the reduction process. In the case where the second layer of the semiconductor element mounting material 100 contains metal oxide particles or composite metal particles, the bonding layer may be formed by performing a reduction process and sintering simultaneously with reduction. Even if the second layer does not contain a metal oxide, since the metal particles may be oxidized during the process, it is preferable to carry out a reduction process to improve the reliability of the bonding.

The reduction process can be performed according to the input of the reducing material. Examples of reducing materials include aldehyde-based compounds such as formaldehyde and acetaldehyde; oxalic acid, formic acid, ascorbic acid, sulfonic acid, dodecyl benzene sulfonic acid, An acid such as maleic acid, hexamic acid, phosphoric acid, O-phthalic acid, or acrylic acid can be preferably used.

When copper oxide is used as the metal oxide, formic acid in gaseous form may be used as the reducing material. When formic acid gas is used, the reduction reaction can be carried out at a temperature of 400 ° C or lower. In the case of copper oxide, since the sintering temperature is below 400 ° C., it is possible to carry out a reduction process using formic acid gas together with the sintering process. Administration of the reducing material is carried out for a sufficient time such that all metal oxides can be reduced.

The sintering process is performed together with the reduction process. Particles contained in the second layer are sintered at the same time as the reduction, so that the particles are mutually diffused to form a junction.

Accordingly, when the semiconductor element mounting material of the present invention is used, it is possible to use relatively inexpensive metal particles by using metal oxides, and the cost is reduced, and the process is performed at a relatively low temperature of 400 DEG C or less and a low pressure of 40 MPa or less It is possible to lower the manufacturing cost and improve the reliability of the bonding between the device and the substrate and the heat dissipation property of the semiconductor device mounting material so that the device can be used in various fields by widening the range of devices that can be used.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, many modifications and changes may be made by those skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims. The present invention can be variously modified and changed by those skilled in the art, and it is also within the scope of the present invention.

100 Semiconductor device mounting material
110 First Floor
120 Second Floor
130 Third Floor
140 composite metal particles
141 metal oxide layer
142 cores
200 device
300 substrate
1000 semiconductor device package

Claims (10)

A first layer comprising a metal film; And
And a second layer formed on at least one surface of the first layer, the second layer including metal particles, metal oxide particles, and composite metal particles comprising a metal oxide layer on the surface, A semiconductor device as set forth in claim 1,
Wherein the second layer is in contact with the semiconductor element and the second layer is formed of only the particles. The method according to claim 1,
The particles may be,
And the remaining portion is located outside the first layer. 2. The semiconductor device according to claim 1, wherein the first layer is formed on the first layer. The method according to claim 1,
When any one of the particles is referred to as a first particle and the other particle is referred to as a second particle,
Wherein the first particles and the second particles are spaced apart from each other. ≪ RTI ID = 0.0 > 11. < / RTI > The method according to claim 1,
Wherein the metal oxide particles and the metal oxide layer comprise an oxide of any one of Cu, Ni, Ag, Ti, Al, and Zn. Preparing a first layer comprising a metal film; And
And forming a second layer by coating at least one particle of metal particles, metal oxide particles, and composite metal particles on the surface of the first layer with a metal oxide layer on one surface of the first layer As a result,
Wherein the second layer is in contact with the semiconductor element and the second layer is formed of only the particles. The method of claim 5,
Wherein forming the second layer comprises:
And embedding a part of at least one of the metal particles, the metal oxide particles, and the composite metal particles including the metal oxide layer on the surface into the first layer. A method of manufacturing an element mounting material. The method of claim 5,
Wherein forming the second layer comprises:
Wherein at least one of the metal particles, the metal oxide particles, and the composite metal particles including a metal oxide layer on the surface thereof is applied to the first layer using a spraying method or a rolling method. A method for manufacturing a semiconductor element mounting material for mounting on a substrate. Board; And
And an element mounted on the substrate,
The device comprises at least one of a metal layer, a metal oxide particle, and a metal oxide layer on the surface, the metal layer being formed on at least one surface of the first layer, And a second layer including a plurality of grains of the semiconductor element mounting material, the semiconductor element mounting material being mounted on the substrate by sintering the semiconductor element mounting material,
Wherein the second layer is in contact with the device and the second layer is formed of only the particles. There is provided a method of manufacturing a semiconductor device, comprising: forming a first layer including a metal film on a substrate; and a composite metal particle formed on at least one surface of the first layer, the composite metal particle including metal particles, metal oxide particles, A semiconductor element mounting reformation step of forming a semiconductor element mounting material including two layers;
Positioning an element on the semiconductor element mounting material; And
And sintering the semiconductor element mounting material, the element mounting method comprising:
Wherein the second layer is in contact with the device, and the second layer is formed of only the particles. The method of claim 9,
Wherein the sintering step further comprises a step of reducing at least one of the metal particles, the metal oxide particles, and the composite metal particles including a metal oxide layer on the surface thereof.

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