JP6008095B2 - Chip surface treatment method, bonding method, and surface treatment apparatus - Google Patents

Description

  The present invention relates to a chip surface treatment method for mounting a chip on a wafer, a chip-on-wafer (COW, Chip-On-Wafer) bonding method, and a surface treatment apparatus therefor.

  In the field of electronics, higher density of device mounting is required. Therefore, a technique for bonding a semiconductor integrated circuit (chip) that has already been packaged onto a wafer (substrate) by a flip chip mounting technique has attracted attention. The chip has a bump-shaped or flat metal region, and the chip is stacked between the chip and the wafer or when the chip is three-dimensionally stacked through the metal region. Electrical connections between multiple chips can be established. Further, the chip may have a part for bonding with a wafer or another chip in order to increase mechanical strength, and this part may be configured as a metal region. Then, by establishing electrical connection between the chip and the wafer or between a plurality of stacked chips via the metal region and increasing the mechanical strength, the plurality of chips or the wafers stacked or stacked. It is possible to increase the speed of electrical signal exchange between chips and to increase the density of electronic device mounting.

  In many cases, a relatively thick oxide film is formed on the surface of a metal region of a chip used for bonding by exposure to oxygen in the atmosphere before the bonding step after the metal region is formed. If the oxide film is not sufficiently removed before bonding, it causes a decrease in conductivity and mechanical strength of the finally formed bonding interface. For this reason, conventionally, diffusion bonding has been performed at a high temperature of 400 ° C. and 150 MPa or higher under a high pressure. In addition, high-pressure bonding of 150 to 300 MPa was necessary even in the surface activated state (Patent Document 1). Furthermore, following the trend of increasing substrate dimensions, there is a need for large bonding systems that can apply more force under similar heating conditions. When a high pressure is applied at the time of bonding, the chip or the substrate may be deformed, and the pressure mechanism of the bonding apparatus must also have a large structure.

  Conventionally, in order to suppress oxidation of the metal region, a vaporizable rust inhibitor (VCI, Volatile Corrosion Inhibitor) has been applied immediately after the formation of the metal region. However, the new surface of the metal region exposed after removing this rust inhibitor by vaporization is oxidized again by contact with oxygen in the atmosphere. Conventionally, in order to eliminate the oxide film, the oxide film has been removed by performing a reduction treatment on the surface of the metal region. However, the new surface of the metal region exposed by the removal of the oxide film is oxidized again by contact with oxygen in the atmosphere.

JP 2004-119430 A

  In order to join the exposed metal region, it is joined by diffusing an oxide film formed on the surface of the metal region into the metal under high temperature and high pressure, or a vacuum in which oxygen is substantially removed until joining, for example. A joining mechanism such as holding the metal region in the atmosphere is required. Such a joining mechanism becomes large and cannot be performed with a simple joining apparatus, and since it takes a predetermined time from the exposure of the new surface of the metal region to the joining, it cannot efficiently avoid the oxidation of the surface of the metal region. There was a problem. Furthermore, in chip-on-wafers, it generally takes several tens of minutes to several hours between the bonding of the first chip to be mounted on the wafer and the bonding of the last chip. The degree of oxidation differs depending on the chip, and there is a problem that the degree of oxidation proceeds toward the last chip. In addition, bonding at high temperature and high pressure is not suitable for bonding between thin wafers or different materials having different thermal expansion, and there is a problem that alignment accuracy deteriorates due to thermal expansion.

  Therefore, the present invention avoids oxidation of the nascent surface of the metal region of the chip as much as possible in the surface treatment, while leaving no undesired residue such as oxide at the bonding interface, and so on before and after the surface treatment. It is an object of the present invention to provide a technique for allowing chips and wafers to be transported and processed in an oxidizing atmosphere and bonding a plurality of chips to a substrate such as a wafer efficiently and stably.

  In the present application, the “chip” is given as a broad concept term indicating a molded semiconductor plate-like component including a semiconductor component, an electronic component such as a packaged semiconductor integrated circuit (IC), and the like. The “chip” includes a component generally called a “die”, a component having a size smaller than that of the substrate, and a size that allows a plurality of components to be bonded to the substrate, or a small substrate. In addition to electronic components, optical components, optoelectronic components, and mechanical components are also included. Moreover, the thing diced from the wafer and arrange | positioned on the adhesive sheet is also included.

  In the present application, the “chip” has a bonding surface bonded to a substrate, and a metal region is formed on the bonding surface. The metal region may be formed so as to protrude from the chip side bonding surface, or may be formed substantially flat. A metal region corresponding to the metal region of the chip-side bonding surface that is opposed at the time of bonding is formed on the bonding surface on the substrate side. By joining the metal region on the chip side bonding surface and the metal region on the substrate side, electrical connection is established between the chip and the substrate, and a predetermined mechanical strength is obtained.

  In the present invention, a wafer (hereinafter referred to as a substrate) includes a plate-shaped semiconductor, but is not limited thereto, and other than the semiconductor, a material such as glass, ceramics, metal, plastic, or a composite material thereof. It may be formed by various shapes such as a circle and a rectangle. Further, the substrate includes a structure including a chip and a substrate formed by bonding chips of one or more layers.

  In order to solve the above technical problem, according to the present invention, a metal region surface treatment method for bonding a chip having a chip-side bonding surface having one or a plurality of metal regions to a substrate is a metal region. In a non-oxidizing atmosphere, after preparing a chip having a vaporizable material coated on the surface thereof, evaporating the vaporizable material to expose the surface of the metal region, and exposing the surface of the metal region And a step of performing a surface activation treatment by colliding particles having a predetermined kinetic energy against the surface of the metal region and a step of applying a hydrophilic treatment by adhering water. . According to the present invention, until the surface treatment method is performed, the vaporizable material is removed from the metal region protected from oxidation by the vaporizable material to expose the new surface in a non-oxidizing atmosphere. On the other hand, by performing the surface activation treatment and the hydrophilization treatment, it is possible to form a clean joint surface that is clean and has a sufficiently low oxidation rate, that is, even in an atmosphere such as air. As a result, it is possible to perform stable temporary bonding that does not depend on the time after the surface treatment using a simple bonding apparatus that does not require a vacuum or the like. In addition, substances that have adhered to the bonding surface such as water and contributed to the temporary bonding disappear during the main bonding, so a clean bonding interface is formed between the chip and the substrate in the final product, and good conductivity is achieved. And a structure including a chip and a substrate having high mechanical strength can be manufactured. Therefore, there is an effect that a large number of chips can be mounted on a substrate while forming a high-performance bonding interface uniformly over a large number of chips with high production efficiency.

  According to the present invention, after the step of exposing the surface of the metal region, the surface activation treatment is performed by colliding particles having a predetermined kinetic energy against the surface of the metal region. . As a result, oxidation of the exposed new surface can be avoided more efficiently, and a clean and stable oxidation surface can be formed, that is, a stable bonding surface can be formed even in an atmosphere such as air.

  According to the present invention, the non-oxidizing atmosphere is an atmosphere containing a vacuum or an inert gas. Thus, by vacuuming the non-oxidizing atmosphere, it is possible to prevent re-deposition of the removed vaporizable material on the surface of the metal region and to form a clean bonding surface. In addition, by using an inert gas in the non-oxidizing atmosphere, a vacuum system or the like is not required, and a surface treatment apparatus can be configured easily.

  According to the present invention, the metal region is formed of copper or a solder material. Thereby, the surface treatment method according to the present invention can be applied to a bonding method of chips on a substrate in a wide range of electronic devices.

  According to the present invention, the vaporizable material is benzotriazole, tolyltriazole, dicyclohexylammonium nitrite, dicyclohexylammonium salicylate, monoethanolamine benzoate, dicyclohexylammonium benzoate, diisopropylammonium benzoate, diisopropylammonium nitrite, cyclohexylamine carbamate, nitronaphthalene. A vaporizable rust inhibitor selected from the group consisting of ammonium nitrite, cyclohexylamine benzoate, dicyclohexylammonium cyclohexanecarboxylate, cyclohexylamine cyclohexanecarboxylate, dicyclohexylammonium acrylate, and cyclohexylamine acrylate, or a linear alkanethio It is obtained to include the Le. These materials are relatively easy to obtain and can protect the metal regions from oxidation and can be easily removed, thus simplifying the surface treatment process and reducing costs.

  According to the present invention, the vaporizable material is vaporized by irradiating the vaporizable material with heat, light, or oxygen plasma. Thereby, the vaporizable material can be efficiently removed.

  According to the present invention, a plurality of chips having a chip-side bonding surface having one or more chip-side metal regions are bonded to a substrate having a substrate-side bonding surface having one or more substrate-side metal regions. The method includes a step of preparing a chip in which a vaporizable material is applied to a surface of a chip-side metal region, a step of exposing the surface of the chip-side metal region, and vaporizing the vaporizable material to form a surface of the chip-side metal region. After the exposing step, surface activation treatment is performed by colliding particles having a predetermined kinetic energy against the surface of the chip-side metal region in a non-oxidizing atmosphere, and hydrophilic treatment is performed by attaching water. And performing surface activation treatment by colliding particles having a predetermined kinetic energy against the surface of the substrate-side metal region in a non-oxidizing atmosphere. And a step of performing hydrophilic treatment by adhering water, and a plurality of chips are arranged so that the chip-side metal region subjected to the hydrophilic treatment is in contact with the substrate-side metal region subjected to the hydrophilic treatment. Attaching to the substrate-side bonding surfaces of the corresponding substrates one by one, forming a structure including a plurality of chips and a substrate, and heating a structure including the plurality of chips and the substrate. It is a thing. According to the present invention, a clean bonding interface can be formed uniformly over a plurality of chips.

  According to the present invention, after the step of exposing the surface of the metal region, the surface activation treatment is performed by colliding particles having a predetermined kinetic energy against the surface of the metal region. . As a result, oxidation of the exposed new surface can be avoided more efficiently, and a clean and stable oxidation surface can be formed, that is, a stable bonding surface can be formed even in an atmosphere such as air.

  According to the present invention, attachment of a plurality of chips to the substrate-side bonding surface is performed in the atmosphere. Thereby, the apparatus for temporary joining can be made into a simple structure.

  According to the present invention, a surface treatment method for a metal region for bonding a chip having a chip-side bonding surface having one or a plurality of metal regions to a substrate includes a chip having an oxide formed on the surface of the metal region. Continuously after the step of preparing, removing the oxide formed on the surface of the metal region by reducing, exposing the surface of the metal region, and exposing the surface of the metal region, a non-oxidizing atmosphere A surface activation treatment by colliding particles having a predetermined kinetic energy against the surface of the metal region, and a step of hydrophilization treatment by adhering water. It is. According to the present invention, until the surface treatment method is performed, the oxide is removed from the metal region to expose the new surface in a non-oxidizing atmosphere, and the exposed new surface is not oxidized. However, the surface activation treatment and the hydrophilization treatment are performed on the new surface, so that a clean and stable oxidation surface can be formed even in an atmosphere such as the atmosphere. . As a result, it is possible to perform stable temporary bonding that does not depend on the time after the surface treatment using a simple bonding apparatus that does not require a vacuum or the like. In addition, substances that have adhered to the bonding surface such as water and contributed to the temporary bonding disappear during the main bonding, so a clean bonding interface is formed between the chip and the substrate in the final product, and good conductivity is achieved. And a structure including a chip and a substrate having high mechanical strength can be manufactured. Therefore, there is an effect that a large number of chips can be mounted on a substrate while forming a high-performance bonding interface uniformly over a large number of chips with high production efficiency.

  According to the present invention, after the step of exposing the surface of the metal region, the surface activation treatment is performed by colliding particles having a predetermined kinetic energy against the surface of the metal region. . As a result, oxidation of the exposed new surface can be avoided more efficiently, and a clean and stable oxidation surface can be formed, that is, a stable bonding surface can be formed even in an atmosphere such as air.

  According to the present invention, reducing the oxide formed on the surface of the metal region is performed by heating the surface of the metal region and irradiating the surface of the heated metal region with an organic acid gas. It is intended to be. Thereby, the oxide can be reduced, and the formed organic acid salt can be decomposed and removed to efficiently expose the nascent surface of the metal region.

  According to the present invention, reducing the oxide formed on the surface of the metal region can be achieved by irradiating the surface of the metal region with a mixed gas containing an organic acid gas and a gas containing hydrogen or hydrogen radicals. It is what was done. Thereby, the oxide can be removed and the new surface of the metal region can be exposed at a comparatively low temperature.

  According to the present invention, the organic acid gas is formic acid gas. Thereby, especially by using formic acid, it is possible to more efficiently remove the oxide and expose the new surface of the metal region.

  According to the present invention, the step of polishing the surface of the metal region is further provided before the step of exposing the surface of the metal region. Thereby, most or all of the oxide on the surface of the metal region can be removed by polishing. Therefore, the thinned oxide can be reduced and removed more efficiently by irradiation with the reducing agent.

  According to the present invention, a method for bonding a plurality of chips having a chip-side bonding surface having one or a plurality of metal regions to a substrate having a substrate-side bonding surface having one or a plurality of metal regions is a chip. Preparing a plurality of chips in which oxide is formed on the surface of the side metal region, and removing the oxide formed on the surface of the chip side metal region by reducing to expose the surface of the chip side metal region After the step and the step of exposing the surface of the chip side metal region, in a non-oxidizing atmosphere, a surface activation treatment is performed by colliding particles having a predetermined kinetic energy against the surface of the chip side metal region, And a step of hydrophilizing by adhering water, and in a non-oxidizing atmosphere, particles having a predetermined kinetic energy collide with the surface of the substrate-side metal region. The surface activation treatment is performed and the hydrophilic treatment is performed by attaching water, and the chip-side metal region subjected to the hydrophilic treatment contacts the substrate-side metal region subjected to the hydrophilic treatment. Attaching a plurality of chips one by one to a substrate-side bonding surface of a corresponding substrate to form a structure including the plurality of chips and the substrate, and a structure including the plurality of chips and the substrate. And a step of heating. According to the present invention, there is an effect that a clean bonding interface can be formed uniformly over a plurality of chips.

  According to the present invention, after the step of exposing the surface of the metal region, the surface activation treatment is performed by colliding particles having a predetermined kinetic energy against the surface of the metal region. . As a result, oxidation of the exposed new surface can be avoided more efficiently, and a clean and stable oxidation surface can be formed, that is, a stable bonding surface can be formed even in an atmosphere such as air.

  According to the present invention, attachment of a plurality of chips to the substrate-side bonding surface is performed in the atmosphere. Thereby, the apparatus for temporary joining can be made into a simple structure.

  According to the present invention, the step of polishing the surface of the metal region is further provided before the step of exposing the surface of the metal region. Thereby, most or all of the oxide on the surface of the metal region can be removed by polishing. Therefore, the thinned oxide can be reduced and removed more efficiently by irradiation with the reducing agent.

  The surface treatment apparatus for a metal region for bonding a plurality of chips having a chip-side bonding surface having one or a plurality of metal regions to a substrate according to the present invention is a vacuum capable of placing the chip therein. Surface activity for colliding particles having a predetermined kinetic energy against the metal region of the chip, heating means for heating the chip, atmosphere control means for controlling the atmosphere in the vacuum vessel to be a non-oxidizing atmosphere And a hydrophilization treatment means for adhering water to the metal region of the chip. According to the present invention, by preparing a chip having a metal region coated with a vaporizable material and protected from oxidation, the vaporizable material is removed without oxidizing the metal region, and stable and clean. It is possible to prepare a surface of a hydrophilized metal region. As a result, in the final product, a clean bonding interface can be formed uniformly and efficiently over a plurality of chips.

  According to the present invention, the vacuum container has a first vacuum container and a second vacuum container, and the first vacuum container has a heating means so that the atmosphere in the first vacuum container becomes a non-oxidizing atmosphere. The second vacuum vessel has surface activation treatment means and hydrophilic treatment means so that the atmosphere in the second vacuum vessel becomes a non-oxidizing atmosphere. It is connected to the second atmosphere control means that controls the chip, so that the chip can be transferred between the first vacuum container and the second vacuum container without breaking the non-oxidizing atmosphere. Thereby, when performing a surface activation process and a hydrophilization process, adhesion of the vaporized material to the surface of a metal area | region can be suppressed.

  The surface treatment apparatus for a metal region for bonding a plurality of chips having a chip-side bonding surface having one or a plurality of metal regions to a substrate according to the present invention is a vacuum capable of placing the chip therein. A container, reducing agent irradiation means for irradiating a reducing agent for reducing oxides in the metal region of the chip toward the metal region of the chip, and atmosphere control means for controlling the atmosphere in the vacuum container to be a non-oxidizing atmosphere The surface activating means for causing particles having a predetermined kinetic energy to collide with the metal region of the chip, and the hydrophilic treatment means for attaching water to the metal region of the chip are provided. According to the present invention, by preparing a chip having a metal region coated with a vaporizable material and protected from oxidation, the vaporizable material is removed without oxidizing the metal region, and stable and clean. It is possible to prepare a surface of a hydrophilized metal region. As a result, in the final product, a clean bonding interface can be formed uniformly and efficiently over a plurality of chips.

  According to the present invention, the vacuum container has a first vacuum container and a second vacuum container, the first vacuum container has a reducing agent irradiation means, and the atmosphere in the first vacuum container is a non-oxidizing atmosphere. The second vacuum vessel has a surface activation treatment means and a hydrophilic treatment means, and the atmosphere in the second vacuum vessel is a non-oxidizing atmosphere. It is connected to the second atmosphere control means for controlling so that the chip can be transported between the first vacuum container and the second vacuum container without breaking the non-oxidizing atmosphere. Thereby, when performing a surface activation process and a hydrophilization process, adhesion of the vaporized material to the surface of a metal area | region can be suppressed.

  According to the present invention, the reducing agent irradiation means has an organic acid gas source for irradiating the organic acid gas, and further has a heating means for heating the chip. Thereby, the oxide on the surface of the metal region can be efficiently reduced and removed.

  According to the present invention, the reducing agent irradiation means has an organic acid gas source that irradiates an organic acid gas, and the organic acid gas source has a heatable catalyst that decomposes the organic acid gas. It is. Thereby, the oxide on the surface of the metal region can be efficiently reduced and removed at a relatively low temperature.

  A surface treatment method for a metal region for bonding a chip having a chip-side bonding surface having one or a plurality of metal regions according to the present invention provides a chip in which an oxide is formed on the surface of a metal region. Removing the oxide formed on the surface of the metal region by polishing to expose the surface of the metal region; and in a non-oxidizing atmosphere, the surface of the metal region is And a step of performing a surface activation treatment by causing particles having a predetermined kinetic energy to collide with each other and a step of applying a hydrophilic treatment by adhering water. According to the present invention, since the thickness of the oxide on the surface of the metal region can be reduced by polishing, the remaining oxide can be sufficiently removed by the surface activation treatment. It becomes unnecessary and surface treatment can be performed more efficiently.

  According to the present invention, a method for bonding a plurality of chips having a chip-side bonding surface having one or a plurality of metal regions to a substrate having a substrate-side bonding surface having one or a plurality of metal regions is a chip. Preparing a plurality of chips in which an oxide is formed on the surface of the side metal region; and removing the oxide formed on the surface of the chip side metal region by polishing to expose the surface of the chip side metal region A step of performing a surface activation treatment by colliding particles having a predetermined kinetic energy against the surface of the chip-side metal region in a non-oxidizing atmosphere, and a step of performing a hydrophilic treatment by adhering water. In a non-oxidizing atmosphere, surface activation treatment is performed by causing particles having a predetermined kinetic energy to collide with the surface of the substrate-side metal region, and water is attached. The step of performing the hydrophilization treatment, and the plurality of chips one by one on the corresponding substrate so that the chip-side metal region subjected to the hydrophilization treatment contacts the substrate-side metal region subjected to the hydrophilization treatment. It is attached to a board | substrate side joining surface, The step which forms the structure containing a some chip | tip and a board | substrate, and the step which heats the structure containing a some chip | tip and a board | substrate are provided. According to the present invention, since the thickness of the oxide on the surface of the metal region can be reduced by polishing, the remaining oxide can be sufficiently removed by the surface activation treatment. It becomes unnecessary, and the chip can be bonded to the substrate more efficiently.

  According to the present invention, attachment of a plurality of chips to the substrate-side bonding surface is performed in the atmosphere. Thereby, the apparatus for temporary joining can be made into a simple structure.

  According to the present invention, a new surface is exposed in a non-oxidizing atmosphere from a metal region that is protected from oxidation until the surface treatment method is performed, and the exposed new surface is prevented from being oxidized while being exposed to the new surface. On the other hand, by performing the surface activation treatment and the hydrophilization treatment, it is possible to form a clean joint surface that is clean and has a sufficiently low oxidation rate, that is, even in an atmosphere such as air. This makes it possible to hold the chip in the atmosphere before and after the surface treatment according to the present invention, and as a result, using a simple bonding device that does not require a vacuum or the like, depends on the time after the surface treatment. Stable temporary joining can be performed. In addition, substances that have adhered to the bonding surface such as water and contributed to the temporary bonding disappear during the main bonding, so a clean bonding interface is formed between the chip and the substrate in the final product, and good conductivity is achieved. And a structure including a chip and a substrate having high mechanical strength can be manufactured. Therefore, there is an effect that a large number of chips can be mounted on a substrate while forming a high-performance bonding interface uniformly over a large number of chips with high production efficiency.

It is a flowchart which shows the surface treatment method of the chip | tip concerning 1st Embodiment. It is sectional drawing which shows typically the process of the surface treatment method of the chip | tip concerning 1st Embodiment. It is a front view which shows schematic structure of a surface treatment system. It is a flowchart which shows the joining method of the chip | tip using the surface treatment method of the chip | tip concerning 1st Embodiment. It is sectional drawing which shows typically the joining process of a chip | tip. It is a flowchart which shows the surface treatment method of the chip | tip concerning 2nd Embodiment. It is a flowchart which shows the joining method of the chip | tip using the surface treatment method of the chip | tip which concerns on 2nd Embodiment.

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

<1. First Embodiment>
<1.1 Joining method>
A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a flowchart showing a surface treatment method for a metal region of a chip-side bonding surface for bonding a chip to a substrate according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view schematically showing the treatment process of the surface treatment method according to the first embodiment of the present invention. FIG. 3 is a front view showing a schematic configuration of the surface treatment system for performing the surface treatment according to the first embodiment of the present invention.

  In step S1, the chip 1 is prepared in which the vaporizable material 3 is applied to the surface of the chip-side metal region 2 formed on the chip-side bonding surface (FIG. 2A). In step S2, the vaporizable material 3 is vaporized in the non-oxidizing atmosphere 4, thereby exposing the surface of the metal region of the chip-side bonding surface (FIG. 2B). In step S3, surface activation is performed by causing particles 6 having a predetermined kinetic energy to collide with the surface 5 of the metal region of the chip-side bonding surface exposed in the non-oxidizing atmosphere 4 continuously from step S2. The hydrophilization treatment is performed (FIG. 2 (c)), and the water 7 is adhered to the surface 5 of the metal region on which the surface activation treatment has been performed (FIG. 2 (d)).

  The vaporizable material applied to the surface of the metal region of the chip prepared in step S1 may be a material that can be removed by heat energy given by heat or light irradiation or by oxygen plasma irradiation. preferable.

  It is preferable to use a vaporizable rust preventive agent (VCI) as the vaporizable material and apply it on the metal region so as to have a thickness of about several tens of nanometers (nm) to several micrometers (μm). It is preferable to employ an appropriate vaporizable rust preventive agent depending on the bonding mode. In general, the vaporizable rust inhibitor can be applied as a protective agent against metal oxidation so as to exhibit a rust prevention effect over several tens of days. Therefore, the chip | tip with which the vaporizable rust preventive agent was apply | coated to the metal area | region can be stored in the stable state over a long period in air | atmosphere. Furthermore, according to the surface treatment according to the present invention, the vaporizable rust inhibitor is sufficiently removed, and by performing the surface activation treatment and the hydrophilic treatment, a relatively stable and clean metal region in the atmosphere is obtained. A surface can be formed.

  As a vaporizable rust preventive, benzotriazole (BTA: benzotriazole), tolyltriazole (TTA: methyl benzotriazole), dicyclohexylammonium dilite (CHI): dicyclohexyl ammonium dilite ammonium salicylate), monoethanolamine benzoate (MEA · BA: monoethanolamine benzoate), dicyclohexylammonium benzoate (DICHA · BA: dicycyclohexyl ammonium benzoate), diisopropyl Pyrammonium benzoate (DIPA / BA: diisopropammonium benzoate), diisopropylammonium nitrite (CHC): cyclohexanamine nitrite (CHC: cyclohexylamine nitrite) Cyclohexylamine benzoate (CHA · BA), dicyclohexylammonium cyclohexanecarboxylate (DICHA · CHC: dicyclohexyl am) cyclohexylamine cyclohexane carboxylate (CHA.CHC) is selected from cyclohexylamine cyclohexylate (CHA.CHC: cyclohexylamine acrylate). Dicyclohexylammonium acrylate (DICHA.AA: dicylcyclohexylamine). preferable. These vaporizable rust preventives are effective for protecting metals, particularly metals that are easily oxidized, such as copper (Cu) and solder materials, from oxidation due to contact with the atmosphere.

  Moreover, you may use alkanethiol as a vaporizable material. By immersing a chip having a metal region in a solution containing an alkanethiol in an organic solvent for several minutes to several tens of hours, a self-assembled molecular (SAM) film made of alkanethiol (SAM, Self-Assembly-Molecular) film is formed. Can be formed on the surface. Further, by vapor-depositing gaseous alkanethiol, a self-assembled molecule (SAM) film of the alkanethiol may be formed on the surface of the metal region. By these methods, the thiol group (SH), which is a functional group, forms a chemical bond with the metal surface, and the van der Waals force acting between adjacent alkyl chains forms a highly oriented monolayer film. It can be formed at a high density on the surface. By forming the SAM film, the rate of surface oxidation when a metal surface such as copper is exposed to an atmosphere such as air containing oxygen can be suppressed.

The alkanethiol may have one or a plurality of branched chains, but is preferably a linear alkanethiol represented by CH ₃ (CH ₂ ) _n-1 SH. Here, n is preferably 1 to 25, and n is preferably 5 to 15. In particular, hexanethiol (n = 6) is preferably used for a copper metal region.

  The alkanethiol may have one or more substituents. Substituents include alkenyl, alkynyl, aryl, carboxyl, amino, hydroxyl, alkoxy, ester, nitrile, amide, mercapto, halogen, ferrocenyl, hydroquinone, pyridyl, para Examples thereof include a hydroxyphenyl group. However, the substituent is not limited to this, and any material may be used as long as the vaporizing material has a function as a self-assembled molecule (SAM) film and suppresses the oxidation rate of the metal region.

  The organic solvent is preferably ethanol, but is not limited thereto. For example, alcohols such as methanol and ethanol, aromatic hydrocarbons such as benzene, and the like can be used. It is preferable to select a solvent as appropriate according to the type of metal constituting the metal region, the reaction temperature, and the like.

<Removal of vaporizable material>
In step S2, the surface of the metal region of the chip-side bonding surface is exposed by vaporizing the vaporizable material in the non-oxidizing atmosphere 4.

  In the present application, the non-oxidizing atmosphere means an atmosphere that does not oxidize the surface of the exposed metal region, or an atmosphere that suppresses oxidation of the surface of the exposed metal region. If an oxide is formed on the surface of the exposed metal region by contact with an oxidizing atmosphere during or after vaporizing the vaporizable material, the oxide will remain at the bonding interface even after the bonding is completed. May remain. The remaining oxide deteriorates properties such as conductivity and mechanical strength at the formed bonding interface. That is, the non-oxidizing atmosphere is an atmosphere that suppresses oxidation of the metal region exposed after vaporization of the vaporizable material to such an extent that sufficient conductivity and mechanical strength can be obtained at the finally formed bonding interface. Means.

  The non-oxidizing atmosphere is the amount of exposure to a gas containing a gas containing a hydroxyl group such as oxygen or water contained in the non-oxidizing atmosphere in the time from the start of step S1 to the start of the surface activation process in step S2. However, it is preferably formed so as to be about 1 L (Langmuir), 1 Torr × s or less.

The non-oxidizing atmosphere is preferably formed by evacuating the atmosphere around the chip with a vacuum pump or the like in step S1. As a result, the amount of vaporized material adhering to the surface of the exposed metal region can be minimized. The degree of vacuum at this time is preferably 1 × 10 ⁻⁵ Pa or less. In addition, by evacuating the atmosphere around the chip with a vacuum pump or the like, the vaporized material is exhausted from the atmosphere around the chip after vaporization, which further reduces the amount of vaporized material attached to the surface of the metal region. it can.

  The non-oxidizing atmosphere may be formed by introducing an inert gas such as nitrogen or argon into the atmosphere around the chip in step S1. As a result, vaporization of the vaporized material is performed in a non-oxidizing atmosphere, and vaporization is performed under low vacuum or atmospheric pressure. Therefore, the need for high vacuum is eliminated and a vacuum system can be easily configured.

  At this time, it is preferable to exhaust the introduced inert gas from the atmosphere around the chip by an amount corresponding to the introduction flow rate. Thereby, since the vaporized material is exhausted from the atmosphere around the chip together with the inert gas, the reattachment amount of the vaporized material to the surface of the metal region can be further reduced.

  The vaporizable material can be vaporized and removed from the surface of the metal region by heating. The vaporizable material includes a material that starts vaporization at a relatively low temperature around 30 degrees Celsius (30 ° C.). However, even in such a vaporizable material, the vaporization rate is increased by heating to a higher temperature, and the vaporizable material can be sufficiently vaporized in a short time. Thereby, the quantity of the residue in the metal area | region surface of the said vaporizable material can be decreased. The heating temperature of the vaporizable material is set according to the vaporization characteristics of the vaporizable material.

  In order to vaporize the vaporizable material, the vaporizable material is preferably heated at a temperature of about 150 degrees Celsius (200 ° C.) to about 300 degrees Celsius (300 ° C.) for several minutes to several tens of minutes. For example, when BTA which is a vaporizable rust preventive agent is used as the vaporizable material, it is preferable to heat to 150 degrees Celsius or higher. In particular, BTA can be sufficiently removed by heating the metal region for about 10 minutes at 250 degrees Celsius. For example, when hexanethiol is used as the vaporizable material, it is preferably heated to 150 degrees Celsius or higher. In particular, it is preferable to heat at about 200 degrees Celsius for about 10 minutes.

  The vaporizable material can be vaporized by heating the vaporizable material by irradiation with heat or light.

  When heat is applied to the vaporizable material, it can be performed, for example, by irradiating infrared rays with an infrared lamp or irradiating ultraviolet rays with an ultraviolet lamp.

  An infrared lamp can be configured at low cost by using a halogen lamp or the like. In addition, since the halogen lamp emits infrared light (IR), particularly light having a wavelength in the so-called near infrared region of 900 nm to 1600 nm, a material containing water molecules can be efficiently heated.

  Since the ultraviolet lamp typically emits light having a wavelength in a so-called ultraviolet (UV) region of 400 nm or less, if the chip has a member that easily absorbs ultraviolet rays such as silicon, it can be heated efficiently. Further, extreme ultraviolet (EUV) having a wavelength of about 150 nm may be irradiated by using an excimer laser.

  By using an infrared lamp or ultraviolet lamp compatible with rapid thermal processing (RTA, RTP), it becomes possible to vaporize the vaporizable material in a short time, and by shortening the heating time to the chip, the characteristics of the chip can be reduced. Changes and contamination of exposed metal areas during the vaporization process can be minimized.

  Alternatively, the chip may be heated by bringing a heated member into contact with the surface opposite to the chip-side bonding surface. For example, a heater may be provided on a support that supports the chip, and the chip may be heated by this heater.

  The vaporizable material may be removed chemically. For example, by irradiating oxygen plasma that decomposes and removes the organic matter, the vaporizable material containing the organic matter as a main component can be removed from the surface of the metal region.

<Surface activation treatment and hydrophilic treatment>
In step S3, a surface activation treatment and a hydrophilization treatment are performed on the surface 5 of the metal region of the chip-side bonding surface exposed in the non-oxidizing atmosphere 4 continuously from the step S2.

  By continuously performing the surface activation treatment and the hydrophilization treatment in step S3 while keeping the surface 5 of the metal region exposed by removing the vaporizable material in step S2 in the non-oxidizing atmosphere 4, a metal is obtained. Hydroxyl groups can be formed on the nascent surface of the material forming the region, or even a layer 7 of water can be formed. These hydroxyl layer and water layer 7 can minimize contact with an oxidizing gas such as oxygen of the material forming the metal region, and can sufficiently slow down the oxidation rate. The joining surface of the metal region can be stably held for a long time.

  By continuously performing steps S2 to S3 in a non-oxidizing atmosphere, the surface of the metal region coated with the vaporizable material that suppresses oxidation is finally made sufficiently clean by making it a clean and stable surface. It is possible to efficiently form a bonding interface having excellent conductivity and mechanical strength.

<Surface activation treatment>
In step S2, a surface activation process is performed by causing particles having a predetermined kinetic energy to collide with the chip-side bonding surface.

  The surface layer can be removed by causing a phenomenon (sputtering phenomenon) in which particles having a predetermined kinetic energy collide to physically blow off the material forming the bonding surface.

It is believed that the vaporizable material not only physically adheres to the metal surface by coating, but also reacts with the metal to form an organic acid salt film. For example, when benzotriazole (BTA) is used as a rust inhibitor for copper (Cu) or a copper alloy, benzotriazole (BTA) reacts with copper (Cu) to form copper oxide such as Cu ₂ O. However, it is believed that a film of benzotriazole copper salt is formed in a polymer form thereon. Therefore, in step S2, the vaporizable material is mostly removed by vaporization, but a part of the film may not be completely removed. Furthermore, a small amount of vaporizable material may remain on the surface of the metal region, or a part of the vaporizable material once vaporized may adhere to the surface of the metal region again. In some cases, contaminants and oxides are formed on the surface of the metal region from which the vaporizable material has been removed. Therefore, by performing a surface activation treatment after the step S2, the oxide remaining on the surface of the metal region, the re-deposited vaporizable material, and the like are further removed, and a new surface of the substance to be bonded is formed. Can be exposed.

  In the surface activation treatment, not only the surface layer is removed to expose the nascent surface of the substance to be bonded, but also the crystal structure near the exposed nascent surface is collided with particles having a predetermined kinetic energy. It is thought that there is also an effect of disturbing and amorphizing. Since the amorphized new surface has a higher surface area at the atomic level and a higher surface energy, it is considered that the number of hydroxyl groups (OH groups) per unit surface area to be bonded in the subsequent hydrophilization treatment is increased. On the other hand, in the case of chemically hydrophilizing after the surface impurity removal step by conventional wet processing, there is no physical change of the nascent surface due to collision of particles having a predetermined kinetic energy. It is considered that the hydrophilization treatment following the surface activation treatment according to the bonding method of the invention is fundamentally different from the conventional hydrophilization treatment in this respect. In addition, atoms in the region near the nascent surface where the crystal structure is disordered and become amorphous easily diffuse with relatively low thermal energy during the heat treatment during the main bonding described later, and the main bonding process at a relatively low temperature. Can be realized.

  As particles used for the surface activation treatment, for example, a rare gas or an inert gas such as neon (Ne), argon (Ar), krypton (Kr), or xenon (Xe) can be employed. These rare gases are unlikely to cause a chemical reaction with a substance that forms a collision surface to be collided, so that a chemical property of the bonding surface is not greatly changed by forming a compound or the like. Further, since it has a relatively large mass, it is considered that a sputtering phenomenon can be efficiently generated and the crystal structure of the nascent surface can be disturbed.

  As particles used for the surface activation treatment, oxygen ions, atoms, molecules, and the like may be employed. By performing the surface activation treatment using oxygen ions or the like, it is possible to cover the new surface with an oxide thin film after removing the surface layer. The oxide thin film on the nascent surface is believed to enhance the efficiency of hydroxyl (OH) group bonding or water attachment in subsequent hydrophilization treatments. Further, it is considered that the oxide thin film formed on the nascent surface decomposes relatively easily during the heat treatment in the main bonding described later.

  It is preferable that the kinetic energy of particles colliding with the surface to be surface activated is 1 eV to 2 keV. It is considered that the above kinetic energy efficiently causes a sputtering phenomenon in the surface layer. A desired value of kinetic energy can also be set from the above kinetic energy range according to the thickness of the surface layer to be removed, the properties such as the material, the material of the new surface, and the like.

  Predetermined kinetic energy can be applied to the particles that collide with the surface-activated joint surface by accelerating the particles toward the joint surface.

  Predetermined kinetic energy can be imparted to the particles using a plasma generator. By applying an alternating voltage to the bonding surfaces of a plurality of chips or substrates, a plasma containing particles is generated around the bonding surfaces, and the cations of the ionized particles in the plasma are bonded to the bonding surfaces by the voltage. A predetermined kinetic energy is given by accelerating toward. Since the plasma can be generated in an atmosphere with a low degree of vacuum of about several pascals (Pa), the vacuum system can be simplified and the steps such as evacuation can be shortened.

  A particle beam source such as a neutral atom beam source or an ion beam source disposed at a position separated from the bonding surface can be used to give a predetermined kinetic energy to the particles. Particles to which a predetermined kinetic energy is applied are emitted from a particle beam source toward bonding surfaces such as a plurality of chips or substrates.

Since the particle beam source operates in a relatively high vacuum, such as 1 × 10 ⁻⁵ Pa (pascal) or less, for example, unnecessary oxidation of the nascent surface or adhesion of impurities to the nascent surface after the surface activation treatment, etc. Can be prevented. Furthermore, since the particle beam source can apply a relatively high acceleration voltage, high kinetic energy can be imparted to the particles. Therefore, it is considered that the removal of the surface layer and the amorphization of the new surface can be performed efficiently.

  As the neutral atom beam source, a fast atom beam source (FAB, Fast Atom Beam) can be used. Fast atom beam sources (FABs) typically generate a plasma of gas, apply an electric field to the plasma, extract the cations of particles ionized from the plasma, and pass them through an electron cloud. It has the composition which becomes. In this case, for example, when argon (Ar) is used as the rare gas, the power supplied to the fast atom beam source (FAB) may be set to 1.5 kV (kilovolt), 15 mA (milliampere), or 0.1 To a value between 500 W (watts). For example, when a fast atom beam source (FAB) is operated from 100 W (watt) to 200 W (watt) and irradiated with a fast atom beam of argon (Ar) for about 2 minutes, the residual vaporizable material, oxide, Contaminants and the like (surface layer) are removed, and the new surface can be exposed.

  In the present invention, the particles used for surface activation may be neutral atoms or ions, may be radical species, and may be a particle group in which these are mixed.

  Depending on the operating conditions of each plasma or beam source, or the kinetic energy of the particles, the removal rate of the surface layer can vary. Therefore, it is necessary to adjust the treatment time required for the surface activation treatment. For example, the presence of oxygen and carbon contained in the surface layer is confirmed using surface analysis methods such as Auger Electron Spectroscopy (AES) and X-ray Photoelectron Spectroscopy (XPS). You may employ | adopt the time which becomes impossible or longer than it as a processing time of a surface activation process.

  In order to make the bonding surface amorphous in the surface activation treatment, the particle irradiation time may be set longer than the time necessary for removing the surface layer and exposing the new surface. The lengthening time may be set to 10 to 15 minutes, or 5% or more of the time required for removing the surface layer and exposing the new surface. The time for making the bonding surface amorphous in the surface activation treatment may be appropriately set according to the type and nature of the material forming the bonding surface and the irradiation conditions of particles having a predetermined kinetic energy.

  In order to make the bonding surface amorphous in the surface activation treatment, the kinetic energy of the irradiated particles is set to be 10% or more higher than the kinetic energy necessary for removing the surface layer and exposing the new surface. Good. The kinetic energy of the particles for making the bonding surface amorphous in the surface activation treatment may be appropriately set depending on the type and property of the material forming the bonding surface and the irradiation conditions of the particles.

  Here, the “amorphized surface” or “surface with disordered crystal structure” specifically includes an amorphous layer whose presence has been confirmed by measurement using a surface analysis technique or a layer with a disordered crystal structure, This is a conceptual term that expresses the state of the crystal surface assumed when the particle irradiation time is set to be relatively long or the particle kinetic energy is set to be relatively high. It includes a surface in which the presence of an amorphous layer or a surface having a disordered crystal structure is not confirmed by the measurement used. Also, “amorphize” or “disturb the crystal structure” conceptually represents the operation for forming the amorphized surface or the surface in which the crystal structure is disturbed.

<Hydrophilic treatment>
In step S2, the hydrophilization treatment is preferably performed in a non-oxidizing atmosphere following the surface activation treatment. However, the hydrophilic treatment may be started before the surface activation treatment is completed. Moreover, you may perform a surface activation process and a hydrophilization process simultaneously. If the surface activation treatment is not performed after completion of the hydrophilic treatment, the temporal relationship between the surface activation treatment and the hydrophilic treatment can be adjusted according to desired conditions.

  It is considered that a layer composed of a hydroxyl group (OH group) is formed on the surface of the metal region that has been subjected to the surface activation treatment by the hydrophilic treatment of the bonding surface, so that water adheres to the surface. By increasing the amount of water attached, water molecules may further adhere to the hydroxyl group (OH group) layer.

  An oxide may be formed on the joint surface by the hydroxylation treatment. However, since the oxide is relatively thin (for example, several nanometers or several atomic layers or less), it is absorbed in the metal material or escapes from the joint interface to the outside as water in the heat treatment during the main joining. It is considered to disappear or decrease. Therefore, in this case, it is considered that there is almost no practical problem in the conductivity through the bonding interface between the chip and the substrate.

The hydrophilization treatment is performed by supplying water to the surface-activated joint surface. The water can be supplied by introducing water (H ₂ O) into the atmosphere around the surface activated bonding surface. Water may be introduced in a gaseous state (in a gaseous state or as water vapor) or in a liquid state (a mist state). Furthermore, as another aspect of the attachment of water, radicals, ionized OH, or the like may be attached. However, the method of introducing water is not limited to these.

  By controlling the humidity of the atmosphere around the surface activated bonding surface, the hydrophilization process can be controlled. The humidity may be calculated as relative humidity, may be calculated as absolute humidity, or other definitions may be employed.

For example, gaseous water is formed by passing a carrier gas such as nitrogen (N ₂ ), argon (Ar), helium (He), oxygen (O ₂ ), etc. into liquid water (bubbling). Water is preferably mixed with the carrier gas and introduced into a space or chamber in which a chip or substrate having a surface activated bonding surface is disposed.

  The introduction of water is preferably controlled so that the relative humidity in the atmosphere around at least one or both of the chip-side bonding surface and the bonding portion of the substrate is 10% to 90%.

For example, when gaseous water is introduced using nitrogen (N ₂ ) or oxygen (O ₂ ) as a carrier gas, the total pressure in the chamber is set to 9.0 × 10 ⁴ Pa (Pascal), that is, 0.89 atm (Atom). The amount of gaseous water in the chamber is 8.6 g / m ³ (grams / cubic meter) or 18.5 g / m ³ (grams / cubic meter) relative to 23 ° C. (23 degrees Celsius) in absolute humidity. The humidity can be controlled to be 43% or 91%, respectively.

Further, the atmospheric concentration of oxygen (O ₂ ) in the chamber may be 10%.

  In the hydrophilic treatment, it is preferable to supply water to the joint surface without exposing the joint surface subjected to the surface activation treatment to the atmosphere. For example, the chamber for performing the surface activation process and the chamber for performing the hydrophilization process may be configured to be the same. Further, the chamber for performing the surface activation treatment and the chamber for carrying out the hydrophilic treatment may be configured to be connected so that a plurality of chips or substrates are conveyed between them without being exposed to the atmosphere. . By adopting these configurations, the surface activation treated bonding surface is not exposed to the atmosphere, thereby preventing unwanted oxidation of the bonding surface, adhesion of impurities, etc. to the bonding surface, and more hydrophilic treatment. It can be easily controlled, and the hydrophilic treatment can be carried out efficiently after the surface activation treatment.

  Further, in order to perform the hydrophilic treatment, air outside the chamber having a predetermined humidity may be introduced. When air is introduced into the chamber, it is preferable that the air passes through a predetermined filter in order to prevent unwanted impurities from adhering to the bonding surface. By introducing the atmosphere outside the chamber having a predetermined humidity and performing the hydrophilic treatment, the configuration of the apparatus for performing the hydrophilic treatment on the joint surface can be simplified.

Alternatively, water (H ₂ O) molecules or clusters may be accelerated and radiated toward the bonding surface. The acceleration of the water (H 2 _O), may be used, such as particle beam source used for the surface activation treatment. In this case, a mixed gas of carrier gas and water (H ₂ O) generated by bubbling or the like is introduced into the particle beam source, thereby generating a water particle beam, and on the joint surface to be hydrophilized. It can be irradiated towards.

  The hydroxyl layer (OH group) layer formed by the hydrophilization treatment or the water layer formed on the hydroxyl layer serves to minimize oxidation of the metal region due to contact with oxygen present in the atmosphere. It is thought that there is.

  Thereby, even if the surface of the metal area | region which completed the hydrophilization process is taken out from a non-oxidizing atmosphere and exposed to air | atmosphere, it is hard to be oxidized and is stable. Therefore, even after the surface of the metal region that has been subjected to the hydrophilization treatment is left in the air for several hours to several tens of hours, a good bonding interface can be obtained in the final product through temporary bonding and main bonding.

  A chip having a metal region that has been subjected to a hydrophilic treatment can be temporarily joined to each chip in 1 to 5 seconds. Accordingly, when 5000 chips are temporarily bonded to one substrate one by one, assuming that the time required for temporary bonding for each chip is 5 seconds, (5 seconds / chip) × (5000 chips) = 25000 seconds = Temporary bonding of all the chips is completed in about 7 hours. In other words, there is a time difference of about 7 hours between the temporary bonding of the first chip and the temporary bonding of the last chip.

  Therefore, according to the surface treatment method according to the present invention, it is sufficient to perform the surface treatment up to the hydrophilic treatment only once for all the chips bonded on one substrate. From a plurality of chips subjected to hydrophilic treatment at the same time, the chips can be temporarily bonded onto a predetermined substrate in the air one by one.

  Since the surface of the metal region for which the hydrophilic treatment has been completed is stable in the air, after the hydrophilic treatment has been completed, the temporary bonding described later can be performed on the chip even in an oxidizing atmosphere such as the air. Thereby, since the joining system which performs temporary joining does not need to be arrange | positioned in a vacuum chamber, it can be comprised simply.

<1.2 Device configuration>
FIG. 3 is a diagram showing a schematic configuration of a surface treatment system 100 for carrying out the surface treatment method according to the present invention.

  In the first vacuum container 101 shown in FIG. 3, a first chip support 102 for supporting the plurality of chips 1, a heating lamp 103 as a heating means, and a first vacuum pump 104 are provided. The chip support 102 is preferably configured to support a plurality of chips 1. By removing the vaporizable material from the plurality of chips 1 at the same time, the efficiency of the surface treatment is improved. The heating lamp 103 is configured to irradiate light with a predetermined wavelength toward the chip.

  Characteristics such as the type of heating lamp, wavelength and intensity of emitted light, and structure are selected or designed according to the material and thickness of the vaporizable material, the material and structure of the chip, the atmosphere in the vaporizable material removal chamber, etc. Is done.

  FIG. 3 shows a heating lamp that irradiates light with a predetermined wavelength toward the chip as means for removing the vaporizable material, but is not limited thereto. For example, a heater may be embedded in the first chip support 102 and the chip may be heated via the first chip support by heat generated by the heater.

  By operating the first vacuum pump 104 connected to the first vacuum vessel 101, the first vacuum vessel 101 can be evacuated and contaminants and vaporized material can be removed from the chamber. Thereby, it can suppress that the contaminant in the 1st vacuum vessel 101 and the vaporized material adhere to the surface of a metal area | region.

  The first vacuum vessel 101 may be configured such that an inert gas such as argon or nitrogen is introduced and exhausted (not shown). By introducing and exhausting the inert gas, the contaminants and vaporized material in the first vacuum vessel 101 can be removed under low vacuum or atmospheric pressure, so that the vacuum system can be simplified. By introducing the inert gas, heat conduction from the heating lamp to the chip can be promoted, and the chip can be heated more uniformly.

  The second vacuum vessel 106 has a gas introduction port 114 for introducing a gas supplied from the plasma generator 109 and the gas source 112 through the gas amount control valve 113 into the second vacuum vessel 106 as surface activation processing means. A water vapor source 115 for generating water vapor as a hydrophilic treatment means, a water vapor introduction port 117 for introducing water vapor supplied from the water vapor source 115 through the water vapor control valve 116 into the second vacuum vessel 106, and a plurality of chips 1. A second chip support 107 that supports and functions as an electrode of the plasma generator 109 and a second vacuum pump 108 are provided. The chip from which the vaporizable material has been removed is transported into the second vacuum container 106 connected to the first vacuum container 101 by the connection valve 105 and placed on the second chip support 107. (The conveying means is not shown.) A second vacuum pump 108 is connected to the second vacuum vessel 106, and the second vacuum vessel 108 is evacuated by the second vacuum pump 108. When transferring chips from the first vacuum vessel 101 to the second vacuum vessel 106, it is preferable to open the connection valve 105 in a state where both vacuum vessels are sufficiently evacuated and a non-oxidizing atmosphere is maintained.

  Most of the material vaporized in the first vacuum vessel 101 is exhausted to the outside after being vaporized by the first vacuum pump 104, but a small amount of the vaporized material is still in the atmosphere in the first vacuum vessel 101. It may remain or be deposited on the inner wall of the first vacuum vessel 101 and discharged again into the atmosphere. Therefore, by separating the second vacuum vessel 106 and the first vacuum vessel 101 so as to be openable and closable while being vacuum-connected, the vaporized material is confined in the first vacuum vessel 101 as much as possible. You can avoid getting lost in the atmosphere. Thereby, contamination of the metal region surface during the surface activation treatment and the hydrophilic treatment by the vaporized material can be minimized.

  The plasma generator 109 includes an alternating power source 110 that operates at an RF frequency, a second chip support 107 as one electrode, and another electrode disposed opposite the second chip support with the placed chip interposed therebetween. 111. A gas to be converted into plasma is introduced from the gas inlet 114 into the second vacuum vessel 106 so as to be supplied from the gas source 112 through the gas amount control valve 113 and between the pair of electrodes 107 and 111. The

In FIG. 3, the plasma generator 109 is shown as the surface activation processing means, but the present invention is not limited to this. For example, a particle beam source such as a neutral atom beam source or an ion beam source may be used as the surface activation means. In order for these beam sources to operate cleanly and efficiently, the second vacuum pump 108 evacuates the atmosphere in the second vacuum vessel 106 to a pressure of about 1 × 10 ⁻⁵ Pa or lower (higher vacuum). It is preferable to be configured to control.

  The partial pressure or humidity of water in the second vacuum vessel 106 is controlled by controlling the amount of water vapor generated by the water vapor source 115, the amount of water vapor introduced by the water vapor control valve 116, and the amount of exhaust by the second vacuum pump 108. Can be adjusted.

  The water vapor source 115 includes, for example, a water tank that stores liquid water and a carrier gas source that sends out a carrier gas such as an inert gas, and causes the carrier gas to bubble through the liquid water. And can be configured to generate a mixed gas of a carrier gas and water vapor. Alternatively, the water vapor source 115 may be configured to mix water vapor formed by evaporating water with heat with the carrier gas. The water vapor source 115 is not limited to these, and can be configured in various forms.

  In FIG. 3, the surface treatment system for carrying out the surface treatment method according to the present invention is composed of two vacuum vessels 101 and 106, but is not limited thereto. A means for heating the vaporized material, a vacuum pump, a surface activation treatment means, and a hydrophilic treatment means are arranged inside one vacuum vessel, and the vaporization material is removed and the surface activation treatment is carried out inside the one vacuum vessel. , And a hydrophilization treatment may be performed.

  Next, with reference to FIG.4 and FIG.5, temporary joining and this joining are demonstrated.

<2. Temporary joining>
In step S4, the surface of the chip-side bonding surface that has been subjected to the surface activation treatment and the hydrophilization treatment through the steps S1 to S3 is such that the surface 5 of the metal region of the chip 1 contacts the bonding portion 9 of the substrate 8 respectively. Mounted on the joint.

  For positioning of the chip with respect to the corresponding joint portion of the substrate, for example, a plurality of position adjustment marks are provided on the chip side, and a plurality of corresponding position adjustment marks are provided on the corresponding joint portion side of the substrate. This may be done by aligning the marks for use. The misalignment between both position adjustment marks is that the transmitted light that is transmitted through the chip and the substrate is incident on the bonding surface in the vertical direction from the chip or the substrate side and is imaged by the camera provided on the opposite side. You may comprise so that it may measure by observing the image of the position adjustment mark by. Thereby, for example, a positioning accuracy of ± 1 μm can be obtained. Furthermore, when the positioning is not sufficient, the chip is once separated from the substrate immediately after the temporary bonding, and the temporary bonding can be repeated after the positioning is performed again until a predetermined positioning accuracy is obtained. Thereby, positioning accuracy of ± 0.2 μm can be obtained.

  It is preferable that the bonding portion 9 of the substrate 8 to which the surface 5 of the metal region of the chip 1 is bonded is formed of metal and is subjected to a surface activation treatment and a hydrophilic treatment prior to step S4. Thereby, the metal region of the chip subjected to the hydrophilic treatment and the bonding portion of the substrate can be temporarily bonded with sufficient strength. Furthermore, by forming a clean surface in the metal region of the chip and the bonding portion of the substrate, it is possible to form a bonding interface with a low impurity content, high conductivity and bonding strength in the final product.

  Hydroxyl (OH) groups are formed or water 10 is adhered to the chip-side bonding surface subjected to the hydrophilization treatment and the bonding portion of the substrate. Temporary bonding is performed by an attractive force such as a hydrogen bond acting between hydroxyl groups or water molecules (FIG. 5A).

  By attaching the chip to the substrate, the chip-side bonding surface and the bonded portion of the substrate are at least in the process from when all of the chips to be bonded are mounted to the substrate until heat treatment is performed. When the structure that is formed by temporary bonding is transported or the position is changed, the chip does not peel off from the substrate or the chip does not deviate from the predetermined mounting position on the substrate. It is fixed with a strong bonding force.

  While all of the plurality of chips to be bonded are temporarily bonded to the substrate, the humidity of the atmosphere around the plurality of chips and the substrate may be maintained at a predetermined value.

  The metal region of the chip is a metal such as a solder material such as copper (Cu), gold tin (Au—Sn) alloy, silver tin (Ag—Sn) alloy, 20 μm (micrometer) square, 3 μm in height (micrometer) ) To 10 μm (micrometer) pad shape, a pressure of 0.5 MPa (megapascal) to 400 MPa (megapascal) is applied to the pad in the direction in which the chip and the substrate are close to each other. Also good.

  If the pressure applied to the pad is too high, the metal regions come into contact with each other due to plastic deformation, causing a short circuit. If the pressure is too low, the predetermined conductivity or bonding strength may not be obtained. Therefore, the pressure applied to the pad is adjusted according to the mechanical characteristics and shape of the material in the metal region, the conditions of the heat treatment in the subsequent main bonding, and the like.

  A plurality of structures including a plurality of chips and substrates obtained by the above temporary bonding can be subjected to heat treatment. Thereby, this invention has an effect that the structure containing the chip | tip and board | substrate which were this joined can be manufactured with high production efficiency. Further, since the chip and the substrate are bonded by a relatively strong hydrogen bond, even if the chip is transported inside or outside the chip mounting system, the risk that the chip slides or peels off from the substrate is small. In addition, since a structure including a plurality of chips and a substrate obtained by temporary bonding is relatively stable, it can be stored in the air for several hours to several days until heat treatment. Therefore, the heat treatment can be performed on the structure including the chip and the substrate at an arbitrary timing.

  The chips to be temporarily bonded may be configured to perform a predetermined inspection on the chips supplied before the temporary bonding and to select only the chips determined to be good. Thus, by mounting only chips that are determined to be good by inspection, the yield of the final product to be produced can be increased.

  The apparatus that performs temporary bonding may be configured to be connected to the surface treatment apparatus illustrated in FIG. 5, or may be configured as a separate apparatus from the surface treatment apparatus illustrated in FIG. 5. (Not shown)

<3. Main joining>
In step S5, predetermined electrical conductivity (resistivity) or bonding strength (mechanical) between the chip and the substrate is obtained by performing heat treatment on the structure of the plurality of chips 1 and the substrate 8 obtained in step S4. Strength) can be obtained (FIG. 5B).

  The maximum temperature during the heat treatment is preferably set to a temperature of 100 ° C. (100 ° C.) or higher and lower than the melting point of the material forming the chip-side metal region 5 and the substrate-side metal region 9.

  By setting the maximum temperature during the heat treatment to 100 ° C. (100 degrees Celsius) or higher, it is considered that most of the hydroxyl (OH) groups or water contained in the bonding interface 11 escapes to the outside of the bonding interface. It is done. At this time, it is considered that in the process of water escaping from the temporary bonding interface, the bonding surfaces that have not been in contact with each other come into contact with each other, the substantial bonding interface expands, and the bonding area increases. In addition, by joining the joint surfaces that have been subjected to the hydrophilic treatment after the surface activation treatment according to the present invention, heating at a temperature exceeding 400 ° C. required for joining using the conventional simple hydrophilization treatment becomes unnecessary. Sufficient bonding strength can be obtained by heating at a temperature of about 0 to 250 ° C.

  Even if the hydroxyl (OH) group or water contained in the bonding interface diffuses into the material around the bonding interface, the electrical or mechanical properties of the portion in the vicinity of the bonding interface are not significantly reduced. Conceivable.

  Further, according to the invention of the present application, even if the maximum temperature during the heat treatment is set below the melting point of the material forming the chip-side metal region 5 and the substrate-side metal region 9, sufficient electrical characteristics and mechanical properties can be obtained. Characteristics can be obtained. In the conventional bonding method, if there is a strong oxide film on the surface of the metal region, it is difficult for atoms to diffuse near the surface. However, the present invention performs a hydrophilic treatment after the surface activation treatment. Since the surfaces of the metal regions are in contact with each other with almost no oxide film, it is considered that solid phase diffusion near the bonding interface is promoted during the main bonding. As a result, it is considered that a substantial bonding interface is expanded and a bonding area is increased by filling a gap between the bonding surfaces that have not been in contact with each other.

  Further, the maximum temperature during the heat treatment is set to be lower than the melting point of the material forming the chip-side metal region 5 and the substrate-side metal region 9, and the main bonding is performed by solid phase diffusion. Can be almost eliminated. Thereby, in the final product, the chip positioning accuracy with respect to a predetermined position on the joint portion of the substrate can be increased, and for example, it can be suppressed to ± 1 μm or less.

  When the maximum temperature during the heat treatment is set to be equal to or higher than the melting point of the material forming the chip-side metal region 5 and the substrate-side metal region 9, the main bonding is performed from the position on the substrate attached by temporary bonding. May shift. This positional deviation may be several μm. If a position shift occurs during the final bonding of the chips, a certain metal region comes into contact with an adjacent metal region, which causes a short circuit. In addition, the bonding area may be reduced, and the bonding strength at the bonding interface may decrease due to a step generated at the bonding interface.

  As described above, as an example, the positioning of the chip with respect to the corresponding joint portion of the substrate is performed by aligning the position adjustment marks provided on the chip side and the substrate side with light transmitted through the chip and the substrate. Is done. Accordingly, the chip is positioned with respect to a predetermined position on the substrate by using a position adjustment mark or the like, and then temporary bonding is performed. Further, in the main bonding, the heating temperature is changed to a material for forming the bonding surface between the chip and the substrate. By setting the temperature below the melting point, the positioning accuracy of the chip with respect to a predetermined position on the bonding portion of the substrate can be extremely increased in the final product. Thereby, while suppressing generation | occurrence | production of defects, such as a short circuit, when stacking | stacking and joining a chip | tip on a laminated substrate, the positioning precision of the vertical direction of the chip over several layers on a board | substrate can be kept high.

  For example, when the metal region of the chip and the bonding portion of the substrate are formed of copper (Cu), the structure of the chip and the substrate after the temporary bonding is heated at 150 ° C. (150 degrees Celsius) for 600 seconds. Thus, a structure of a chip and a substrate having high conductivity and bonding strength can be obtained.

  When the metal region between the chip-side bonding surface and the bonding portion of the substrate is formed of copper (Cu), it is sufficient to apply a pressure of about 0.14 MPa (megapascal) in the direction perpendicular to the bonding interface. Conductivity and mechanical strength are obtained.

  Conventionally, in order to directly bond copper (Cu) and copper (Cu), it has been necessary to maintain a force of several tons per substrate for about 10 minutes at a high temperature of about 350 ° C. (350 degrees Celsius). However, by adopting copper as a material for forming the metal region in the present invention, it is possible to manufacture a chip-substrate structure having desired conductivity and mechanical strength at low temperature, low pressure, and high speed. .

  Each metal region of the chip is made of nickel (Ni), gold (Au), tin (Sn), tin-silver alloy, other solder materials, etc., 20 μm (micrometer) square, 3 μm high (micrometer) ) To 10 μm (micrometer) in the form of a pad, a pressure of 0.5 MPa (megapascal) to 400 MPa (megapascal) may be applied to each pad during the heat treatment.

  The atmosphere around the structure during the heat treatment may be air, but is preferably a nitrogen or rare gas atmosphere in order to suppress oxidation of the metal region. Further, the humidity of the atmosphere around the structure during the heat treatment may be adjusted or suppressed.

  By adopting a bonding method having temporary bonding and main bonding according to the present invention, the production efficiency of COW mounting is remarkably improved as compared with the conventional bonding method. For example, by repeatedly performing temporary bonding and main bonding to the bonding portion on the substrate corresponding to each chip, and comparing with a case where a predetermined number of chips are mounted on the substrate, the effect of the present invention can be improved. I can understand.

The comparison is made when 5000 chips are bonded on one substrate.
It is said that it takes about 60 seconds per chip when temporary bonding and main bonding are repeated for each chip as in the past. Therefore, for example, it takes (60 seconds / chip) × (5000 chips) = 300000 seconds = about 83 hours to fully bond 5000 chips on one substrate. Even if temporary bonding and main bonding for each chip are performed in 10 seconds, in order to perform main bonding of 5000 chips on one substrate, (10 seconds / chip) × (5000 chips) = 50000 seconds = about 14 It takes time.

  According to the bonding method according to the present invention, temporary bonding can be performed in 1 to 5 seconds for each chip. Therefore, when 5000 chips are temporarily bonded on one substrate in 1 second per chip, (1 second / chip) × (5000 chips) = 5000 seconds = about 1.4 hours, the temporary bonding is completed. To do. Therefore, it can be understood that even if the main bonding is performed at a relatively low temperature for several hours, the production time is remarkably reduced as compared with the conventional method. Further, when 5000 chips are temporarily bonded on one substrate in 5 seconds per chip, the temporary bonding is completed in (5 seconds / chip) × (25000 chips) = 5000 seconds = 7 hours. Therefore, even if the main joining is performed in less than 7 hours, the production time can be shortened compared to 14 hours, which is the time required for performing temporary joining and main joining using the conventional joining method described above. Understood. Although the time required for the main bonding depends on the heating temperature, it can be less than 7 hours.

<4. Second Embodiment>
A second embodiment of the present invention will be described with reference to FIGS. FIG. 6 is a flowchart showing a surface treatment method of a chip joint surface for joining a chip to a substrate according to the second embodiment of the present invention. FIG. 7 is a flowchart showing a chip bonding method using the chip surface treatment method according to the second embodiment.

  In step S6, a chip in which an oxide is formed on the surface of the metal region formed on the chip-side bonding surface is prepared. In step S7, the oxide is reduced and removed in a non-oxidizing atmosphere to expose the surface of the metal region. Step S3 subsequent to step S7 is the same as step 3 in FIG. That is, the surface activation treatment and the hydrophilic treatment are performed on the surface of the exposed metal region of the chip-side bonding surface in a non-oxidizing atmosphere continuously from step S7.

  In FIG. 7, following the steps S6, S7 and S3 shown in FIG. 6, the step S4 of temporarily bonding the chips having been subjected to the hydrophilic treatment to the substrate one by one, and the plurality of chips and the substrate having been temporarily bonded, The process S5 which carries out the main joining by heating the structure containing this is shown. Here, step S4 and step S5 are the same as step S4 and step S5 shown in FIG.

  An oxide may be formed thick on the surface of the metal region. In such a case, if the oxide is removed by the surface activation treatment, there is a problem that the surface activation treatment for a long time is required and cannot be removed efficiently. In order to solve this problem, in the present embodiment, before the surface activation treatment, the oxide is reduced by irradiating the surface of the metal region with a reducing agent. By reducing the oxide, it is possible to efficiently expose the nascent surface of the metal region by removing the substance generated by the reduction.

  It is preferable to use hydrogen plasma as the reducing agent. For example, when the metal region is formed of copper (Cu), the above plasma generator is used to introduce a gas composed of 90% hydrogen, 10% inert gas of argon or nitrogen, and generate at 100W. By exposing the metal region to the hydrogen plasma for about 120 seconds, the copper oxide placed on the surface of the metal region can be reduced.

  An organic acid gas can also be used as the reducing agent. When an organic acid gas is sprayed onto the surface of the metal oxide, a metal organic acid salt is formed. By thermally decomposing this organic acid salt, the oxidized metal surface can be reduced and the oxide can be removed. For example, when the metal region is formed of copper (Cu), the copper oxide formed on the surface of the metal region is heated and sprayed with formic acid gas on the surface of the metal region, thereby reducing and removing the copper oxide. be able to.

  At this time, the copper formate formed by the reaction of formic acid with copper is decomposed at a temperature of 250 degrees Celsius to 300 degrees Celsius or higher. Therefore, in step S7, the metal region is preferably maintained at a temperature of 250 degrees Celsius to 300 degrees Celsius or higher.

  In addition, before irradiating the surface of the metal region with an organic acid such as formic acid, at least part of the organic acid gas by the catalyst is decomposed, thereby generating hydrogen or hydrogen radicals effective for reducing the copper oxide layer. Thus, the surface of the metal region can be irradiated with a mixed gas containing an organic acid gas and hydrogen or hydrogen radicals.

  It is desirable to use heated platinum (Pt) as a catalyst for decomposing formic acid.

  Thereby, the temperature of the metal area | region in process S7 can be hold | maintained at 200 degrees C or less. Further, in the absence of hydrogen or hydrogen radicals, the amount of undecomposed organic acid salt that would remain on the surface of the metal region can be reduced, and the reliability of the joint can be increased.

  Furthermore, nitrogen gas is usually used as a carrier gas when an organic acid is vaporized and sprayed onto the metal surface. Therefore, when the organic acid is decomposed, free carbon is generated, which causes the bonding to be inhibited. Therefore, by using an inert argon gas as a carrier gas, an excessive reduction action is suppressed, and residual free carbon is suppressed.

  The surface treatment apparatus that performs the surface treatment according to the second embodiment includes, for example, a reducing agent irradiation unit (not shown) that irradiates the chip with a reducing agent substantially at the position of the heating lamp 103 of the surface treatment apparatus shown in FIG. ) May be provided.

  Furthermore, the surface of the metal region may be polished before the step of reducing the oxide by irradiating the surface of the metal region with a reducing agent. Thereby, even when the oxide is formed thick on the surface of the metal region, most or all of the oxide can be removed by polishing. Therefore, since the remaining oxide is relatively thin, it can be reduced and removed more efficiently by irradiation with a reducing agent.

  Since the thickness of the oxide on the surface of the metal region can be reduced by polishing, this oxide may be sufficiently removed by the surface activation treatment. In this case, irradiation with a reducing agent is unnecessary and surface treatment can be performed more efficiently. Therefore, after performing predetermined polishing for removing oxides, the chip is carried into a vacuum vessel, and surface activation treatment and hydrophilic treatment are performed on the surface of the metal region. Through the bonding and the main bonding, sufficient conductivity and mechanical strength can be obtained at the finally formed bonding interface.

  For example, the polishing may be performed by a chemical mechanical polishing (CMP) method used in a semiconductor device manufacturing process. The conditions of chemical mechanical polishing (CMP) include the chemical components of the slurry and the mechanical properties of the abrasive particles, depending on the metal that forms the metal region, the material that forms the region other than the metal region, and the arrangement at the joint surface of both. It can be determined by the operating conditions of the polishing apparatus, such as the properties of the polishing pad, the relative movement of the substrate and the polishing pad, and the pressing conditions.

  For example, when the metal region is formed of copper (Cu) as a main component, a slurry containing colloidal silica as main abrasive grains can be used.

  Although silicon dioxide (silica) was mentioned as a component of the abrasive particles contained in the slurry, it is not limited thereto. For example, cerium oxide (ceria), aluminum oxide (alumina), zirconium oxide (zirconia), titanium dioxide (titania), tin oxide are used depending on the nature of the metal forming the metal region and the operating conditions of the polishing apparatus. May be.

  The slurry is preferably suspended in the CMP composition as a colloidal stable colloidal dispersion. “Colloid” means a suspension of abrasive particles in a liquid. “Colloidal stability” means maintaining its suspension with minimal precipitation for a selected period of time.

  Moreover, it is preferable that the slurry contains an oxidizing agent such as a surfactant or hydrogen peroxide. These concentrations and ratios can be adjusted.

  Further, the method of polishing is not limited to CMP. For example, the polishing in the present invention includes grinding and lapping. By grinding the metal surface, the crystal structure near the surface of the metal region is disturbed. In CMP, the thickness of the surface layer whose crystal structure is disturbed can be kept extremely small, whereas the thickness of the surface layer whose crystal structure is disturbed by grinding becomes relatively large, for example, several tens to several tens of micrometers. Sometimes it becomes. The surface of the metal region where the crystal structure is disturbed is considered to have a higher surface energy. Therefore, by adopting grinding as polishing, it is considered that the hydrophilic treatment can be performed more efficiently as described later, and the main joining process at a relatively low temperature can be realized.

  As mentioned above, although several embodiment and the Example of this invention were described, these embodiment and an Example demonstrate this invention exemplarily. The scope of the claims encompasses many modifications to the embodiments without departing from the technical idea of the present invention. Accordingly, the embodiments and examples disclosed herein are presented for purposes of illustration and should not be considered as limiting the scope of the present invention.

1 chip 2 chip side metal region 3 vaporizable material 4 non-oxidizing atmosphere
5 Metal region 6 on chip-side bonding surface 7 Particle having predetermined kinetic energy 7 Water layer 8 Substrate 9 Substrate bonding portion 10 Water 100 Surface treatment system 101 First vacuum vessel 102 First chip support 103 Heating lamp 104 First Vacuum pump 105 Connection valve 106 Second vacuum vessel 107 Second chip support 108 Second vacuum pump 109 Plasma generator 110 Alternating power supply 111 Electrode 112 Gas source 113 Gas amount control valve 114 Gas inlet 115 Steam source 116 Steam control valve 117 Steam inlet

Claims (18)

A method for bonding one or more chips having a chip side bonding surface having one or more chip side metal regions to a substrate having a substrate side bonding surface having one or more substrate side metal regions. There,
Preparing a chip in which a vaporizable material is applied to the surface of the chip-side metal region;
Vaporizing the vaporizable material in a non-oxidizing atmosphere to expose the surface of the chip-side metal region;
After the step of exposing the surface of said chip-side metal regions, in a non-oxidizing atmosphere, and row Cormorant step surface activation treatment by colliding particles with a predetermined kinetic energy to the surface of the chip-side metal regions ,
Performing a hydrophilic treatment by adhering water;
In a non-oxidizing atmosphere, and row Cormorant step surface activation treatment by colliding particles with a predetermined kinetic energy to the surface of the substrate side metal region,
Performing a hydrophilic treatment by adhering water;
Attach one or more chips one by one to the substrate-side bonding surface of the corresponding substrate so that the chip-side metal region that has undergone hydrophilic treatment contacts the substrate-side metal region that has undergone hydrophilic treatment. Forming a structure including one or more chips and a substrate;
Heating the structure including the one or more chips and a substrate;
A method of bonding one or more chips to a substrate. Continuously after the step of exposing the surface of the chip side metal region, surface activation treatment is performed by colliding particles having a predetermined kinetic energy against the surface of the chip side metal region in a non-oxidizing atmosphere. A method of bonding one or more chips according to claim 1 to a substrate. The method for bonding one or more chips to a substrate according to claim 1 or 2 , wherein the one or more chips are attached to the substrate-side bonding surface of the substrate in the atmosphere. The method of bonding one or more chips according to any one of claims 1 to 3, wherein the chip-side metal region is formed of copper or a solder material. The vaporizable material is benzotriazole, tolyltriazole, dicyclohexylammonium nitrite, dicyclohexylammonium salicylate, monoethanolamine benzoate, dicyclohexylammonium benzoate, diisopropylammonium benzoate, diisopropylammonium nitrite, cyclohexylamine carbamate, nitronaphthaleneammonium nitrite, cyclohexyl A vaporizable rust inhibitor selected from the group consisting of amine benzoate, dicyclohexylammonium cyclohexanecarboxylate, cyclohexylamine cyclohexanecarboxylate, dicyclohexylammonium acrylate, and cyclohexylamine acrylate, or a linear alkanethiol. How one or more of the chips is bonded to a substrate according to any one of paragraphs 1 to 4. The vaporization of the vaporizable material is performed by irradiating the vaporizable material with heat, light, or oxygen plasma, or one or more according to any one of claims 1 to 5. Method of bonding the chip to the substrate. A method for bonding one or more chips having a chip-side bonding surface having one or more metal regions to a substrate having a substrate-side bonding surface having one or more metal regions,
Preparing a plurality of chips in which an oxide is formed on the surface of the chip-side metal region;
Removing the oxide formed on the surface of the chip-side metal region by reducing in a non-oxidizing atmosphere, and exposing the surface of the chip-side metal region;
After the step of exposing the surface of said chip-side metal regions, in a non-oxidizing atmosphere, and row Cormorant step surface activation treatment by colliding particles with a predetermined kinetic energy to the surface of the chip-side metal regions ,
Performing a hydrophilic treatment by adhering water;
In a non-oxidizing atmosphere, and row Cormorant step surface activation treatment by colliding particles with a predetermined kinetic energy to the surface of the substrate side metal region,
Performing a hydrophilic treatment by adhering water;
Attach one or more chips one by one to the substrate-side bonding surface of the corresponding substrate so that the chip-side metal region that has undergone hydrophilic treatment contacts the substrate-side metal region that has undergone hydrophilic treatment. Forming a structure including one or more chips and a substrate;
Heating the structure including the one or more chips and a substrate;
A method of bonding one or more chips to a substrate. Continuously after the step of exposing the surface of the chip side metal region, surface activation treatment is performed by colliding particles having a predetermined kinetic energy against the surface of the chip side metal region in a non-oxidizing atmosphere. A method for bonding one or more chips according to claim 7 to a substrate. The method for bonding one or more chips to a substrate according to claim 7 or 8 , wherein the one or more chips are attached to the substrate-side bonding surface of the substrate in the atmosphere. Before the step of exposing the surface of said chip-side metal regions, further comprising the step of polishing the surface of the chip-side metal regions, substrate one or more chips of any one of claims 7 to 9 How to join to. Reducing the oxide formed on the surface of the chip-side metal region is to heat the surface of the chip-side metal regions, by irradiating the organic acid gas with respect to the heated surface of the chip-side metal regions 11. A method for bonding one or more chips according to any one of claims 7 to 10 to a substrate . Mixed gas reducing the oxide formed on the surface of the chip-side metal regions, including the surface of the oxide formed on the chip side metal region, and a gas containing an organic acid gas and hydrogen or a hydrogen radical The method of joining one or several chip | tips as described in any one of Claim 7 to 10 to a board | substrate performed by irradiating . Performing a surface activation process by causing particles having a predetermined kinetic energy to collide with the surface of the chip side metal region, and causing particles having a predetermined kinetic energy to collide with the surface of the substrate side metal region; 13. The method of bonding one or more chips to a substrate according to any one of claims 1 to 12, wherein the step of performing the surface activation process is performed using a particle beam source. Performing a surface activation process by causing particles having a predetermined kinetic energy to collide with the surface of the chip side metal region, and causing particles having a predetermined kinetic energy to collide with the surface of the substrate side metal region; 14. The chip or chips according to any one of claims 1 to 13, wherein the surface activation processing step makes the surface of the chip-side metal region and the surface of the substrate-side metal region amorphous. A method of bonding the substrate to the substrate. A metal region surface treatment apparatus for bonding a plurality of chips having a chip side bonding surface having one or a plurality of metal regions to a substrate,
A vacuum container in which the chip can be placed;
Heating means for heating the chip;
Atmosphere control means for controlling the atmosphere in the vacuum vessel to be a non-oxidizing atmosphere;
Surface activation treatment means for colliding particles having a predetermined kinetic energy against the metal region of the chip;
Hydrophilic treatment means for attaching water to the metal region of the chip;
With
The vacuum vessel has a first vacuum vessel and a second vacuum vessel,
The first vacuum vessel has the heating means, and is configured to be connected to first atmosphere control means for controlling the atmosphere in the first vacuum vessel to be a non-oxidizing atmosphere,
The second vacuum container has the surface activation processing means and the hydrophilic treatment means, and is connected to second atmosphere control means for controlling the atmosphere in the second vacuum container to be a non-oxidizing atmosphere, A surface treatment apparatus configured to transfer a chip between the first vacuum container and the second vacuum container without breaking the non-oxidizing atmosphere . A metal region surface treatment apparatus for bonding a plurality of chips having a chip side bonding surface having one or a plurality of metal regions to a substrate,
A vacuum container in which the chip can be placed;
Reducing agent irradiation means for irradiating the metal region of the chip with a reducing agent that reduces the oxide in the metal region of the chip;
Atmosphere control means for controlling the atmosphere in the vacuum vessel to be a non-oxidizing atmosphere;
Surface activation treatment means for colliding particles having a predetermined kinetic energy against the metal region of the chip;
Hydrophilic treatment means for attaching water to the metal region of the chip;
With
The vacuum vessel has a first vacuum vessel and a second vacuum vessel,
The first vacuum vessel has the reducing agent irradiation means, and is connected to first atmosphere control means for controlling the atmosphere in the first vacuum container to be a non-oxidizing atmosphere,
The second vacuum container has the surface activation processing means and the hydrophilic treatment means, and is connected to second atmosphere control means for controlling the atmosphere in the second vacuum container to be a non-oxidizing atmosphere, A surface treatment apparatus configured to transfer a chip between the first vacuum container and the second vacuum container without breaking the non-oxidizing atmosphere . A method for bonding one or more chips having a chip-side bonding surface having one or more metal regions to a substrate having a substrate-side bonding surface having one or more metal regions,
Preparing a plurality of chips in which an oxide is formed on the surface of the chip-side metal region;
Removing the oxide formed on the surface of the chip side metal region by polishing to expose the surface of the chip side metal region;
In a non-oxidizing atmosphere, and row Cormorant step surface activation treatment by colliding particles with a predetermined kinetic energy by using a particle beam source to the surface of the chip side metal region,
Performing a hydrophilic treatment by adhering water;
In a non-oxidizing atmosphere, and row Cormorant step surface activation treatment by colliding particles with a predetermined kinetic energy by using a particle beam source to the surface of the substrate side metal region,
Performing a hydrophilic treatment by adhering water;
Attach one or more chips one by one to the substrate-side bonding surface of the corresponding substrate so that the chip-side metal region that has undergone hydrophilic treatment contacts the substrate-side metal region that has undergone hydrophilic treatment. Forming a structure including one or more chips and a substrate;
Heating the structure including the one or more chips and a substrate,
Performing a surface activation process by causing particles having a predetermined kinetic energy to collide with the surface of the chip side metal region using a particle beam source; and a particle beam source for the surface of the substrate side metal region One or a plurality of chips that amorphize the surface of the chip-side metal region and the surface of the substrate-side metal region by performing a surface activation process by colliding particles having a predetermined kinetic energy using A method of bonding to a substrate. 18. The method of bonding one or more chips to a substrate according to claim 17 , wherein the mounting of the one or more chips to the substrate side bonding surface is performed in the atmosphere.

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