JP5914076B2 - Metal sheet for filling, metal filling method using metal sheet for filling, and method for producing metal sheet for filling - Google Patents

Description

The present invention, filler metal sheets to be used for filling a molten metal into the minute space formed on the surface of the filling objects, metal filling method and a manufacturing method of filling a metal sheet using the filler metal sheet About.

  Conventionally, as a technique for filling a metal into vias or through holes (microspaces) formed on the surface of a semiconductor wafer (filling object), for example, after melting and heating the metal in a storage tank, the molten metal is used as a semiconductor. Supply the metal so that it spreads over the wafer and pressurize the metal into the micro space by pressurizing, or heat and melt the metal in the storage tank, then immerse the filling object in this storage tank, A method of filling a metal with metal has been used.

  However, in the above conventional metal filling method, since a large amount of metal needs to be stocked in the storage tank in a molten state, the apparatus is increased in size, the heating system for heating the metal is increased in capacity, and the amount of material consumed. There has been a problem that the apparatus cost and running cost such as increase and construction of means for maintaining the properties of the molten metal increase. In addition, there has been a problem that it takes a great deal of cost and labor to recover and reuse surplus molten metal supplied onto the wafer.

  Therefore, as a more efficient and economical metal filling method, a metal filling method using sheet-shaped metal disclosed in Japanese Patent Application Laid-Open Nos. 2002-368082 and 2011-228571 has been proposed.

  In the method disclosed in Japanese Patent Application Laid-Open No. 2002-368082, a metal sheet is overlaid on one surface of a sample in which a minute space is formed so as to cover the minute space, and the metal sheet is heated and melted in a decompressed chamber. Thereafter, the inside of the chamber is pressurized, and the molten metal is vacuum sucked into a minute space.

  In addition, the method disclosed in Japanese Patent Application Laid-Open No. 2011-228571 is a method in which a filling base material in which a metal layer is formed is opposed to one surface of a base material in which a minute space is opened in a decompressed chamber. In this method, after laminating and heating and melting the metal layer, the molten metal is pressurized (pressing pressure, rolling pressure, gas pressure, etc.) to fill the inside of the minute space with the molten metal. The filling substrate has a structure in which a metal layer is formed on at least one surface of a support base made of glass or a heat-resistant synthetic resin film.

  In these methods, since a metal sheet made of an amount of metal necessary for filling a minute space is heated and melted on a filling object, and the molten metal is filled in the minute space, the storage tank In addition, since the metal is formed into a sheet shape, the heat transfer efficiency is good, the heating system for heating the metal can be reduced in size, and the apparatus cost and running cost can be suppressed as compared with the conventional method. Further, since it is not necessary to melt a large amount of metal in the storage tank, the material utilization efficiency is good and the cost can be reduced.

Japanese Patent Laid-Open No. 2002-368082 JP 2011-228571 A

  However, as a result of intensive studies, the inventors of the present application have found that in the metal filling method in the micro space using the metal sheet, the molten metal is not uniformly filled into the micro space on the filling object, or It has been found that there is a problem in that the molten metal is not sufficiently filled in the minute space, resulting in poor filling.

  The major cause of the above problem is that when the metal sheet is heated and melted on the object to be filled, the molten metal is deformed into a shape or a spherical shape that is biased by surface tension, so that the surface of the object to be filled is made uniform by the molten metal. It is not covered with.

  That is, the wettability of the molten metal to the surface of the object to be filled is poor, and the molten metal flows so that the contact angle with the object to be filled becomes large. The molten metal is not filled in the minute space of the part, or a sufficient amount of the molten metal is not filled in the minute space.

  In this way, if the molten metal is not filled in a part of the minute space, or if a sufficient amount of the molten metal is not filled in the minute space, when the filling object is a semiconductor wafer, It becomes a defective product with defects.

The present invention has been made in view of the above circumstances, and provides a metal filling method capable of uniformly and reliably filling molten metal into a minute space, a metal sheet used for the metal filling method, and a filling metal. The object is to provide a sheet manufacturing method .

The present invention is a metal filling method for filling the molten metal into the filler object surface is formed so as to open the micro space, a method for producing a filler metal sheets and fill metal sheets used for the metal filling method.

The above metal filling method is
On one side, a metal sheet making process for creating a filling metal sheet in which a deteriorated layer containing an altered component obtained by oxidizing or embrittlement of a base metal is formed,
A placing step of placing the filling metal sheet on the surface of the filling object in a state where the back surface of the one surface is in contact with the surface of the filling object;
Heating the metal sheet for filling and melting the base metal; and
A pressurizing step of applying a pressure in a direction in which the molten metal is pressed against the entire surface of the object to be filled is performed on the molten metal.

  According to this metal filling method, first, a filling metal sheet in which a modified layer containing a modified component obtained by oxidizing or embrittlement of a base metal is formed on one surface.

  As an example of a method for creating a metal sheet for filling in which a deteriorated layer is formed, a base metal (metal to be filled in a minute space) is melted on a heated production plate and stirred by applying ultrasonic vibration. , A method in which a thermal oxide is levitated on the surface and thinly spread on a preparation plate in a state where an oxide layer is formed, and this is cured, or a method in which one surface of a substrate is chemically oxidized using an oxidizing agent, A method in which a liquid metal such as gallium or mercury is brought into contact with one surface of the substrate and this one surface is embrittled with a liquid metal, and a denatured component that has oxidized or embrittled the substrate metal is deposited on one surface of the substrate. An example of the method is as follows. The metal to be filled may be any material such as Au, Ag, Cu, Pt, Pd, Ir, Al, Ni, Sn, In, Bi, Zn, and alloys thereof depending on the purpose and function of filling the minute space. Can be adopted.

  Next, the prepared filling metal sheet is placed on the surface of the filling object with the surface on which the altered layer is not formed being in contact with the surface of the filling object, and then the filling metal sheet is heated. The base metal is melted. At this time, it is preferable to melt other than the deteriorated layer.

  Thereafter, a pressure is applied to press the molten metal onto the entire surface of the object to be filled, and the molten metal is filled into the minute space. As a method of applying pressure to the molten metal, a method of applying press pressure can be given as an example.

  In the metal filling method, a filling metal sheet is prepared in which a modified layer containing a modified component obtained by oxidizing or embrittlement of a base metal is formed on one surface, and the filling metal sheet is used as a filling object. It is made to heat and melt on the surface. In general, an altered layer (an oxidized layer or an embrittled layer) containing an altered component obtained by oxidizing or embrittlement of a base metal has low fluidity. Therefore, an altered layer is formed on one surface of a filling metal sheet. As a result, the flow of the molten metal is suppressed, and an effect of preventing the phenomenon that the molten metal is repelled on the surface of the filling object and the surface area is reduced can be obtained. Therefore, the surface of the filling object is uniformly covered with the molten metal.

  Then, by applying a pressure in a direction in which the molten metal is pressed against the entire surface of the object to be filled while maintaining a state where the surface of the object to be filled is uniformly covered, Since it can be pushed into the space, the molten metal can be uniformly filled in the minute space of the filling object.

The thickness of the altered layer is preferably set to a thickness that can suppress the fluidity of the molten metal when the molten metal is filled into the minute space. Specifically, the metal sheet for filling is used. The thickness is 10 μm or more from one surface of the substrate . In addition, it is preferable to set it as the thickness of 200 micrometers or less from the one surface of the metal sheet for filling . Moreover , although the thickness of the metal sheet for filling assumes the thickness of several dozen micrometer-several hundred micrometer, it is not restricted to this.

  Further, the altered layer may be formed such that when the filling metal sheet is placed on the filling object, the size in plan view is substantially the same as that of the filling object. It may be formed on one entire surface.

  Furthermore, the placing step, the heating step, and the pressurizing step in the metal filling method may be performed in a sealed processing chamber, and a depressurizing step for depressurizing the processing chamber may be further performed.

  In this case, after reducing the pressure inside the processing chamber, the filling metal sheet is heated and melted, and a pressure is applied to press the molten metal against the entire surface of the filling object, thereby filling the minute space with the molten metal. At this time, examples of the method for applying pressure to the molten metal include a method of applying a press pressure and a method of applying a gas pressure.

  Note that the size of the minute space formed on the filling object is typically assumed to have a diameter of 0.1 μm to several tens of μm. It does not matter whether it is a through hole, regardless of the form such as the formation method and aspect ratio. Moreover, if it is a non-through-hole, the depth can be made into arbitrary things by several hundred micrometers or less according to the thickness of a filling object.

As described above, the metal filling method according to the present invention, according to the production method of filling the metal sheet and the filler metal sheet used for the metal filling method, without the use of a composed support substrate of glass or film The state in which the surface of the filling object is uniformly covered with the molten metal is prevented by suppressing the flow of the molten metal and preventing the phenomenon that the molten metal is repelled on the surface of the filling object and the surface area is reduced. Thus, the molten metal can be uniformly and reliably filled in the minute space.

It is sectional drawing which showed the metal sheet for filling used for the metal filling method which concerns on one Embodiment of this invention. It is sectional drawing which showed the metal filling apparatus used for the metal filling method which concerns on one Embodiment of this invention. It is explanatory drawing for demonstrating operation | movement of the metal filling apparatus in this embodiment. It is explanatory drawing for demonstrating operation | movement of the metal filling apparatus in this embodiment. It is explanatory drawing for demonstrating operation | movement of the metal filling apparatus in this embodiment. It is explanatory drawing for demonstrating operation | movement of the metal filling apparatus in this embodiment. It is explanatory drawing for demonstrating operation | movement of the metal filling apparatus in this embodiment. It is sectional drawing which shows the board | substrate with which the molten metal was filled in micro space. It is sectional drawing which shows the board | substrate which removed the metal residue. It is sectional drawing which showed the metal filling apparatus used for the metal filling method which concerns on other embodiment of this invention. It is explanatory drawing for demonstrating operation | movement of the metal filling apparatus in other embodiment. It is explanatory drawing for demonstrating operation | movement of the metal filling apparatus in other embodiment. It is explanatory drawing for demonstrating operation | movement of the metal filling apparatus in other embodiment. It is explanatory drawing for demonstrating operation | movement of the metal filling apparatus in other embodiment. It is sectional drawing which showed the metal filling apparatus used for the metal filling method which concerns on other embodiment of this invention. It is explanatory drawing for demonstrating operation | movement of the metal filling apparatus in other embodiment. It is explanatory drawing for demonstrating operation | movement of the metal filling apparatus in other embodiment. It is explanatory drawing for demonstrating operation | movement of the metal filling apparatus in other embodiment. It is explanatory drawing for demonstrating operation | movement of the metal filling apparatus in other embodiment.

  Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings.

  In the metal filling method according to an embodiment of the present invention, a filling metal sheet having an altered layer formed on one entire surface is prepared, the filling metal sheet is heated and melted on the surface of the substrate, and the molten metal is removed. This is a method of filling a minute space formed on the surface of a substrate.

  First, the metal sheet for filling will be described with reference to FIG. FIG. 1 is a cross-sectional view schematically showing the filling metal sheet M.

  As shown in FIG. 1, the filling metal sheet M is formed on the entire surface of one of the filling layer M1 containing the metal (base metal) to be filled in the minute space and the filling layer M1, It consists of a modified layer M2 having a modified component obtained by modifying the base metal constituting the packed layer M1 as a structural component.

  As the constituent components of the filling layer M1, Au, Ag, Cu, Pt, Pd, Ir, Al, Ni, Sn, In, Bi, Zn, and these can be used depending on the purpose and function of filling the minute space. Arbitrary things, such as an alloy, can be adopted.

  The altered layer M2 has a thickness that can suppress the flow of the molten metal when the filling metal sheet M is heated and melted and the molten metal is filled into the minute space. Yes. Specifically, the thickness of the altered layer M2 is preferably a thickness in the range of 10 μm to 200 μm. In this example, the thickness of the filling metal sheet M is assumed to be several tens of μm to several hundreds of μm, and the thickness of the altered layer M2 is set to about 10 μm, but is not limited thereto. .

  Such a filling metal sheet M can be prepared by adopting various methods. As an example, a metal to be filled in a minute space is melted on a preparation plate such as a heated quartz plate, An example is a method in which ultrasonic vibration is applied and agitated, the thermal oxide is floated on the surface, and is thinly spread on a preparation plate in a state where an oxide layer is formed and then cured. In addition, when the metal to be filled in the minute space is melted on the heated production plate, the produced filling metal is formed by using a production plate made of a material having a coefficient of thermal expansion different from that of the metal to be filled. The sheet | seat M can be easily peeled from a preparation board using the difference in a thermal expansion coefficient.

  Further, as another method for producing the filling metal sheet M, one surface of a base material containing a metal to be filled in a minute space as a constituent component is chemically oxidized using an oxidizing agent, thereby On the other hand, a method of forming an oxide layer that is an altered layer on the surface, or a liquid metal such as gallium or mercury is brought into contact with one surface of the substrate, and this one surface is embrittled to form an embrittled layer that is an altered layer. Examples thereof include a method of depositing a denatured component obtained by oxidizing or embrittlement of a base metal on one surface of the substrate to form a denatured layer (oxidized layer or embrittled layer).

  The altered layer M2 in the filling metal sheet M thus produced has lower fluidity than the packed layer M1.

  Although FIG. 1 shows a state where the packed bed M1 and the altered layer M2 are completely separated, the packed bed M1 and the altered layer M2 do not have to be completely separated, and the packed bed M1. It may change in steps from the altered layer M2.

  Next, a metal filling apparatus for carrying out the metal filling method will be described. FIG. 2 is a cross-sectional view showing a schematic configuration of the metal filling device 1.

  As shown in FIG. 2, the metal filling apparatus 1 is provided so as to be movable forward and backward with respect to a base 2 on which the substrate K is held with its surface facing up and a surface of the substrate K held on the base 2. The pressing member 3, the pressing mechanism 4 for moving the pressing member forward and backward, the cylinder 5 provided so as to be movable up and down, in which the processing chamber 6 is formed, the lifting mechanism 7 for moving the cylinder 5 up and down, A decompression mechanism 8 that decompresses the inside of the processing chamber 6 and a heating mechanism 14 that heats the substrate K and the filling metal sheet M placed on the surface of the substrate K are configured.

  The pressing member 3 is a so-called piston having a columnar shape, and is inserted from the upper opening of the cylindrical body 5, and is advanced and retracted in the axial direction by the pressing mechanism 4. An O-ring 12 is interposed between the outer peripheral surface of the pressing member 3 and the inner peripheral surface of the cylinder 5, and the gap between the two is sealed by the O-ring 12.

  As described above, the cylindrical body 5 is moved up and down by the elevating mechanism 7. The cylindrical body 5 is lowered toward the base 2, and the lower end surface of the cylindrical body 5 is set to the upper surface of the base 2. The processing chamber 6 becomes a hermetically sealed space. At this time, the space between the two is sealed by the O-ring 13 interposed between the lower end surface of the cylinder 5 and the upper surface of the base 2.

  The pressing mechanism 4 includes a torque motor that generates a driving force for moving the pressing member 3 forward and backward, and can press the pressing member 3 against the substrate K with a predetermined pressing force. Similarly, the elevating mechanism 7 includes a torque motor that generates a driving force for elevating and lowering the cylindrical body 5.

  The decompression mechanism 8 includes a vacuum pump 9 connected to the processing chamber 6 by a pipe 11 penetrating the side wall of the cylindrical body 5, and the vacuum pump 9 between the piping 11 and the processing chamber 6. This is a mechanism comprising an on-off valve 10 provided and exhausting the air in the processing chamber 6 by the vacuum pump 9 to reduce the pressure.

  The heating mechanism 14 is composed of a heater or the like provided inside the base 2, and the filling metal sheet M placed on the substrate K is equal to or higher than the melting point of the base metal constituting the filling layer M <b> 1. It is a mechanism for heating and melting to a temperature of.

  Next, a process of filling a metal in a minute space by performing a metal filling method according to an embodiment of the present invention using the above-described filling metal sheet M and metal filling device 1 will be described with reference to FIGS. This will be described in detail with reference to FIG.

  First, a filling metal sheet M to be heated and melted on the substrate K is prepared. As described above, various methods can be adopted as a method for producing the filling metal sheet M. Here, a specific production in the case where the constituent component of the filling layer M1 is lead-free solder is used. A method will be described.

  First, a quartz plate is heated on a heating plate heated to 100 to 150 ° C. Next, using a soldering iron equipped with an ultrasonic output function, the solder is melted on the heated quartz plate, and then the molten solder is spread on the quartz plate in a state where ultrasonic vibration is applied. At this time, the solder given the ultrasonic vibration pushes away bubbles and thermally oxidized solder from the interface with the quartz plate so as to follow the quartz plate. As a result, the thermally oxidized solder gathers on the upper surface. Then, after the thermally oxidized solder is gathered on the upper surface, the quartz plate is returned to room temperature to cure the solder. In this way, the filling metal sheet M is formed in which the filling layer M1 containing solder as a constituent component and the altered layer (oxide layer) M2 containing solder thermal oxide as a constituent component are formed.

  In this method for producing the metal sheet M for filling, the thermal expansion coefficients of the solder and the quartz plate are different. Therefore, when the quartz plate is returned to room temperature, the solder is peeled off from the quartz plate due to the difference in thermal expansion coefficient. It is easy. Further, by using a quartz plate having a small surface roughness, a filling metal sheet M having a small surface roughness on the surface on the packed layer M1 side can be produced.

  Next, the filling metal sheet M is placed on the surface of the substrate K with the filling layer M1 and the surface of the substrate K facing each other. At the same time, the cylinder 5 is raised by driving the lifting mechanism 7 of the metal filling device 1 to open the processing chamber 6. Then, the substrate K and the filling metal sheet M are put into the opened processing chamber 6 and placed on the base 2 (see FIG. 3).

  Next, the cylinder 5 is lowered by driving the elevating mechanism 7, the lower end surface of the cylinder 5 and the upper surface of the base 2 are brought into contact with each other, the process chamber 6 is sealed, and then the vacuum pump 9 is operated. Then, the on-off valve 10 is opened, the air in the processing chamber 6 is exhausted, and the pressure is reduced until the inside of the processing chamber 6 is in a substantially vacuum state (see FIG. 4). At this time, the inside of the minute space of the substrate K placed on the base 2 is also decompressed to a substantially vacuum state.

  Next, as shown in FIG. 5, the pressing mechanism 4 is driven to lower the pressing member 3, press the metal sheet for filling M against the substrate K and fix it, and then the heating mechanism 14 is operated. Then, the filling metal sheet M is heated and melted to a temperature equal to or higher than the melting point of the metal constituting the filling layer M1 of the filling metal sheet M. Since the altered layer M2 is an oxide layer composed of an oxide, the melting point of the oxide is higher than the melting point of the unoxidized metal, and the metal constituting the filling layer M1 is melted first.

  Next, as shown in FIG. 6, the pressing member 3 is further lowered, and a pressure is applied to the molten metal so as to press the molten metal against the entire surface of the substrate K, thereby forcing the molten metal into the minute space. Note that when the molten metal is pushed into the minute space, it is preferable to prevent the molten metal from leaking by an appropriate sealing member.

  In the filling metal sheet M of this example, an altered layer M2 having low fluidity is formed on the filled layer M1, and the thickness of the altered layer M2 is a thickness capable of suppressing the flow of molten metal. It is said. Therefore, by the action of the altered layer M2, when the filling metal sheet M is heated and the filling layer M1 is melted, the molten metal is prevented from flowing so as to aggregate and disperse on the surface of the substrate K. Then, the surface of the substrate K is uniformly covered with the molten metal. As a result, the molten metal can be uniformly and reliably filled into the minute space formed on the surface of the substrate K. Further, since the filling layer M1 is melted first and filled into the minute space, the filling of the constituent component (the thermal oxide of the solder) of the altered layer M2 into the minute space is suppressed.

  Then, after a sufficient time has elapsed, the heating mechanism 14 is stopped while the pressure in the pressing direction is applied to the molten metal, and the substrate K and the molten metal filled in the minute space are solidified. Cool the molten metal sufficiently. The method of cooling the substrate K and the molten metal may be a method of natural cooling, or a method of cooling by a cooling mechanism as appropriate.

  Thereafter, as shown in FIG. 7, the operation of the vacuum pump 9 is stopped, air is appropriately taken into the processing chamber 6 through the leak valve, the processing chamber 6 is returned to atmospheric pressure, and the pressing mechanism 4 is driven to perform pressing. While raising the member 3 and driving the elevating mechanism 7, the cylinder 5 is raised to open the processing chamber 6, and the substrate K filled with metal in the minute space is taken out from the base 2.

  A sectional view of the substrate K taken out is shown in FIG. As shown in the figure, the minute space is filled with the filling layer M1. Then, by removing metal residues (filled layer M1 and altered layer M2) that are not filled in the minute space from the substrate K, as shown in FIG. 9, the molten metal is filled with no gaps. It becomes the substrate K.

  Thus, according to the metal filling method of the present example, the filling metal sheet M on which the altered layer M2 is formed is heated on the surface of the substrate K to melt the filling layer M1, so that the molten metal becomes the substrate K. Thus, the molten metal can be prevented from flowing so as to be agglomerated and dispersed, and a state in which the molten metal uniformly covers the surface of the substrate K can be maintained. Therefore, the molten metal can be uniformly and surely filled into the minute space formed on the surface of the substrate K.

  As mentioned above, although one Embodiment of this invention was described, the specific aspect which this invention can take is not limited to this at all.

  In this example, after the metal sheet for filling is heated and melted in the decompressed processing chamber, the pressed metal is further pushed into the minute space by the pressing member. Alternatively, it may be performed in an open space. In this case, the metal filling device 20 shown in FIG. 10 is used. The metal filling device 20 includes the base 2, the pressing member 3, the pressing mechanism 4, and the heating mechanism 14 in the metal filling device 1, and is installed in an open space.

  Hereinafter, the process of filling the molten metal into the minute space using the metal filling device 20 will be described with reference to FIGS.

  First, similarly to the above example, a filling metal sheet M composed of a filling layer M1 and an altered layer M2 is prepared, and after the created filling metal sheet M is placed on the surface of the substrate K, the substrate K Is placed on the base 2 (see FIG. 11). Next, by driving the pressing mechanism 4, the pressing member 3 is lowered and the filling metal sheet M is pressed against the substrate K to be fixed, and then the heating mechanism 14 is operated so that the filling metal sheet M is placed on the substrate K. Heating is performed to melt the packed bed M1 (see FIG. 12). When the packed layer M1 is melted, the flow of the molten metal is suppressed by the action of the altered layer M2 as in the above example, so that the molten metal uniformly covers the surface of the substrate K.

  Thereafter, the pressing member 3 is further lowered, and a pressure is applied to the molten metal so as to press the molten metal against the entire surface of the substrate K, so that the molten metal is pushed into the minute space (see FIG. 13). Then, the operation of the heating mechanism 14 is stopped while maintaining the state where the pressure is applied to the molten metal, the substrate K and the molten metal are cooled to solidify the molten metal, and then the substrate K is placed on the base 2. (See FIG. 14).

  As described above, even when the filling metal sheet is melted and the molten metal is filled into the minute space in the open space, the surface of the substrate K can be uniformly covered with the molten metal as in the above example. In addition, since the pressure that presses the molten metal against the entire surface of the substrate K can be applied to the molten metal, the molten metal can be uniformly and reliably filled in the minute space. The metal filling device 20 in this example can be used particularly suitably when the molten metal has good wettability with respect to the minute space of the substrate K.

  In this example, the pressing member applies a pressure in a direction in which the molten metal is pressed against the entire surface of the substrate. However, the pressure is not limited to this. For example, an inert gas is supplied into the processing chamber. Then, a similar pressure may be applied to the molten metal by gas pressurization. A method of filling the molten metal in the minute space by applying pressure to the molten metal by gas pressurization will be described below. This method is performed using a metal filling apparatus 30 shown in FIG.

  As shown in FIG. 15, the metal filling device 30 uses a cup-shaped container 31 in which a processing chamber 6 is formed instead of the cylindrical body 5 in the metal filling device 1. It has the structure provided with the gas supply mechanism 32 which supplies an inert gas to. In addition, in FIG. 15, the same code | symbol was attached | subjected about the same component as the metal filling apparatus 1. FIG.

  Similar to the cylindrical body 5, the container 31 has a processing chamber 6 formed therein, and is moved up and down by an elevating mechanism 7. Similarly, the lower end surface of the container 31 and the upper surface of the base 2. Makes a space in which the processing chamber 6 is sealed.

  The gas supply mechanism 32 includes a gas supply unit 33 connected to the processing chamber 6 by the pipe 11 and an on-off valve 34 provided between the gas supply unit 33 and the processing chamber 6 of the pipe 11. The gas supply unit 33 is configured to supply an inert gas such as nitrogen gas into the processing chamber 6.

  Hereinafter, the process of filling the molten metal into the minute space using the metal filling device 30 will be described with reference to FIGS.

  First, as in the above example, the container 31 is raised by the elevating mechanism 7 to open the processing chamber 6 and the substrate K on which the filling metal sheet M is placed on the surface is placed on the base 2. (See FIG. 16) The container 31 is lowered to seal the processing chamber 6, the vacuum pump 9 is operated, the open / close valve 10 is opened, and the inside of the processing chamber 6 is decompressed to a substantially vacuum state. Next, the heating mechanism 14 is operated to heat the filling metal sheet M on the substrate K and melt the filling layer M1 (see FIG. 17). At this time, similarly to the above example, the flow of the molten metal is suppressed by the function of the deteriorated layer M2, and the molten metal uniformly covers the surface of the substrate K. As a result, the minute space and the processing chamber 6 are isolated from each other by the molten metal.

  Thereafter, the on-off valve 10 is closed and the on-off valve 34 is opened to supply an inert gas into the processing chamber 6 (see FIG. 18). Thereby, a pressure difference is generated between the minute space and the inside of the processing chamber 6, and the molten metal is sucked into the minute space of the substrate K by vacuum. In addition, as described above, the action of the altered layer M2 prevents the molten metal from flowing so as to increase the contact angle with the surface of the substrate K, and the surface of the substrate K is uniformly formed by the molten metal. Therefore, a pressure is applied to the molten metal in such a direction that the molten metal is pressed against the entire surface of the substrate K. That is, the molten metal is gas-pressed, and the molten metal is minute. The space is filled.

  Then, after a sufficient time has passed, the operation of the heating mechanism 14 is stopped while supplying the inert gas into the processing chamber 6, the substrate K and the molten metal are cooled, and the molten metal is solidified. Thereafter, as shown in FIG. 19, the on-off valve 34 is closed to stop the supply of the inert gas into the processing chamber 6, and the processing chamber 6 is opened after the inside of the processing chamber 6 is returned to atmospheric pressure. The substrate K filled with metal in the space is taken out.

  As described above, even when the metal melted by gas pressurization is filled in the minute space, the state in which the molten metal uniformly covers the surface of the substrate K can be maintained as in the above example. Therefore, the molten metal can be uniformly and surely filled in the minute space by applying a pressure to the molten metal against the entire surface of the substrate K.

  In addition, you may make it apply the press pressure by a pressing member, and the gas pressure by an inert gas. Even in this case, similarly, the molten metal can be uniformly and reliably filled into the minute space.

DESCRIPTION OF SYMBOLS 1 Metal filling apparatus 2 Base 3 Pushing member 4 Pushing mechanism 5 Cylindrical body 6 Processing chamber 7 Lifting mechanism 8 Depressurization mechanism 14 Heating mechanism 20 Metal filling apparatus 30 Metal filling apparatus 31 Container 32 Gas supply mechanism M Filling metal sheet M1 Filling layer M2 alteration layer K substrate

Claims (8)

A method of filling molten metal into a minute space formed so as to open on the surface of a filling object,
On one side, a metal sheet making process for creating a filling metal sheet in which a deteriorated layer containing an altered component obtained by oxidizing or embrittlement of a base metal is formed,
A placing step of placing the filling metal sheet on the surface of the filling object in a state where the back surface of the one surface is in contact with the surface of the filling object;
Heating the metal sheet for filling and melting the base metal; and
The molten metal, have rows and a pressure applying pressure direction for pressing the molten metal on the entire surface of the filler object,
A metal filling method, wherein the altered layer has a thickness of 10 μm or more from one surface of the filling metal sheet . A method of filling molten metal into a minute space formed so as to open on the surface of an object to be filled in a processing chamber,
On one side, a metal sheet making process for creating a filling metal sheet in which a deteriorated layer containing an altered component obtained by oxidizing or embrittlement of a base metal is formed,
A placing step of placing the filling metal sheet on the surface of the filling object in a state where the back surface of the one surface is in contact with the surface of the filling object;
A decompression step of decompressing the processing chamber;
Heating the metal sheet for filling and melting the base metal; and
The molten metal, have rows and a pressure applying pressure direction for pressing the molten metal on the entire surface of the filler object,
A metal filling method, wherein the altered layer has a thickness of 10 μm or more from one surface of a filling metal sheet .   3. The metal filling method according to claim 1, wherein the deteriorated layer is formed on one surface of the filling metal sheet by thermal oxidation, chemical oxidation, or liquid metal embrittlement. The metal filling method according to any one of claims 1 to 3, wherein the altered layer has a thickness of 200 µm or less from one surface of the metal sheet for filling. A metal sheet for filling that is heated and melted on a filling object and is filled in a minute space opened on the surface of the filling object,
On one side, the base metal comprises a deteriorated layer containing the altered components in a state of being oxidized or embrittled,
The filling metal sheet, wherein the altered layer has a thickness of 10 μm or more from one surface of the filling metal sheet.   6. The metal sheet for filling according to claim 5, wherein the altered layer is formed on one surface of the metal sheet for filling by thermal oxidation, chemical oxidation or liquid metal embrittlement. The metal sheet for filling according to claim 5 or 6, wherein the altered layer has a thickness of 200 µm or less from one surface of the metal sheet for filling. A method for producing a metal sheet for filling, which is heated and melted on a filling object and is filled in a micro space opened on the surface of the filling object,
Forming a modified layer containing a modified component obtained by oxidizing or embrittlement of the base metal on one surface;
A method for producing a metal sheet for filling, wherein the altered layer has a thickness of 10 μm or more from one surface of the metal sheet for filling.

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