JP3716403B2 - Projection electrode forming substrate and method of forming projection electrode using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a protruding electrode forming substrate suitable for forming protruding electrodes collectively on a plurality of semiconductor elements formed on a wafer, and a protruding electrode forming method using the same.
[0002]
[Prior art]
Currently, the number of connection terminals for connecting a semiconductor element and a circuit board tends to increase, and accordingly, the size of the connection terminals has become minute.
[0003]
In order to form such a fine connection terminal with high accuracy, the Si plate is anisotropically etched to form a square pyramid-shaped recess at a position corresponding to the connection terminal, and the recess is filled with a solder paste. A technique is known in which a metal sphere is formed in a recess by heating, the metal sphere and the connection terminal are aligned, and the metal sphere is transferred onto the connection terminal by heating to form a protruding electrode. (Refer to Japanese Patent Laid-Open No. 7-249631 if necessary.)
[0004]
Also known is a technique for depositing a predetermined amount of solder on a Si plate through a metal mask, aligning the solder with the connection terminal, and heating to form a protruding electrode on the connection terminal as described above. It has been.
[0005]
Conventionally, when any of the above methods is adopted, the protruding electrodes are formed in units of chips. However, in recent years, the protruding electrodes are collectively formed at the wafer stage before cutting into chips for the purpose of reducing the cost. Things have been done.
[0006]
FIGS. 10 and 11 are sectional views for explaining a main part showing a wafer or the like at a process point for explaining an example in the prior art, and will be described below with reference to these drawings.
[0007]
Refer to FIG.
10- (1)
A semiconductor element is formed, and a wafer 1 on which connection terminals 2 are formed is set up and down and set on a jig (not shown), and a recess 4A having a quadrangular pyramid shape is formed and recessed. A forming plate 4 made of an Si plate holding a metal ball 3 formed by heating a solder paste in the place 4A is set on a jig (not shown) and is made to face.
[0008]
Refer to FIG.
10- (2)
The connection terminals 2 on the wafer 1 and the metal balls 3 held on the forming plate 4 are aligned and brought into contact with each other.
[0009]
Refer to FIG.
10- (1)
Heat treatment is performed in a state where the connection terminal 2 and the metal ball 3 are in contact with each other, and the metal ball 3 is transferred to the connection terminal 2.
[0010]
In this case, since the connection terminal 2 and the metal ball 3 are both miniaturized, the gap G between the wafer 1 and the forming plate 4 is very narrow.
[0011]
Refer to FIG.
11- (2)
The whole is immersed in a cleaning solution, and the wafer 1 and the forming plate 4 are peeled off.
[0012]
As described above, the gap G between the wafer 1 and the forming plate 4 is narrow, and the size of the wafer 1 is large. Therefore, when immersed in the cleaning liquid, the cleaning liquid is in the gap G. Hard to enter and difficult to peel off.
[0013]
In particular, when flux is used when transferring the metal spheres 3 to the connection terminals 2, peeling is difficult.
[0014]
[Problems to be solved by the invention]
In the present invention, the metal ball is transferred to the connection terminal and then immersed in the cleaning liquid to separate the wafer and the forming plate so that the forming plate is warped so that the cleaning liquid can easily enter, and the wafer and the forming plate are separated. Try to be simple and easy.
[0015]
[Means for Solving the Problems]
In the present invention, when a resin film is formed on a forming plate for holding a metal sphere and immersed in a cleaning liquid, it is fundamental that the forming plate is warped by the action of the resin film. However, the resin film in that case should be warped at room temperature, or flat at room temperature, but it should be warped by taking some means when immersed in the cleaning liquid. It is either.
[0016]
In any case, when the connection terminal and the metal ball are aligned and transferred, the forming plate must be kept flat, and when the wafer and the forming plate are peeled off, the forming plate must be warped. In order to realize it, a device is required.
[0017]
In this case, a thermosetting resin such as polyimide or epoxy is extremely useful, and various operations such as blending are necessary. For example, it is easy to obtain a polyimide having a different coefficient of thermal expansion. Among them, those that generate warpage at room temperature and become less warped when heated to about 100 [° C.], or glass transition temperature T _g In the vicinity of normal temperature, and those having many characteristics such as those that warp when the temperature is lower than normal temperature can be obtained.
[0018]
FIG. 1 and FIG. 2 are side views of the principal part showing the forming plate and the resin film holding metal balls for explaining the characteristics of various resin films, and are the same as the symbols used in FIG. 10 and FIG. The symbols shall represent the same part or have the same meaning.
[0019]
Refer to FIG.
In the illustrated example, a thermosetting resin is applied to the side (hereinafter referred to as the back side) opposite to the side (hereinafter referred to as the front side) that holds the metal balls 3 that are the solder balls on the forming plate 4. And the appropriate temperature is selected, it is possible to generate a warp as described above the forming plate 4.
[0020]
Refer to FIG.
In the example shown in the figure, a warp added above the forming plate 4 is generated by applying a thermosetting resin on the surface side of the forming plate 4 to form the resin film 5A and selecting an appropriate application temperature. Can do.
[0021]
Although it can be known from the direction of warping seen in FIG. 1B, the resin film 5B and the resin film 5A have different characteristics, and the applied temperature is also different, so the resin film 5B is formed. Even if it is formed on the surface side of the plate 4, warping occurs in the same direction as in the case of FIG.
[0022]
Refer to FIG.
In the illustrated example, a thermosetting resin is applied to the back side of the forming plate 4 to form a resin film 5B, and a thermosetting resin is also applied to the front side of the forming plate 4 to form and apply a resin film 5A. By appropriately selecting the temperature, no warpage occurs as indicated above the forming plate 4.
[0023]
Refer to FIG.
In the illustrated example, the resin film 5B in the example described with reference to FIG. 2A is peeled off by, for example, laser beam irradiation, and is appropriately selected above the formation plate 4 by appropriately selecting the application temperature. Warpage can be generated.
[0024]
FIG. 3 is an explanatory view of the principal part showing the resin film and data for explaining the characteristics of the resin film. (A) shows the resin film and (B) shows the data. The same symbols as those used in the above description represent the same parts or have the same meaning.
[0025]
As shown in FIG. 3A, the resin film 6 is formed by laminating resin films 6A and 6B having different characteristics, and the resin film 6 has a low temperature or a high temperature deviating from a certain temperature. The warp noted above is generated.
[0026]
FIG. 3B shows the characteristics of the resin film 6A and the resin film 6B. The horizontal axis represents temperature [° C.] and the vertical axis represents stress [MPa]. The characteristic line indicated by A corresponds to the resin film 6A, and the characteristic line indicated by B corresponds to the resin film 6B.
[0027]
As is apparent from the figure, when the application temperature is low, the stress of the resin film 6A is large, so that the warp occurs in the direction described with reference to FIG. The warpage is reduced, and when the temperature is increased beyond that, the stress of the resin film 6B is increased and the warp is generated in the direction described with reference to FIG.
[0028]
In the present invention, the various characteristics of the resin film as described above are utilized to generate warpage in the forming plate when necessary. However, when the connection terminals and the metal balls are transferred in alignment, It is necessary to keep the forming plate flat. For this purpose, there are means using a vacuum chuck and a magnet, means for appropriately selecting the temperature to be applied, means for using a plurality of resin films, etc. Is clarified in the description of the embodiment.
[0029]
From the above, in the bump electrode forming substrate and the bump electrode forming method using the same according to the present invention,
(1)
A resin film (for example, a recess 4A) for receiving a metal sphere (for example, a metal sphere 3 made of solder) and a warp with a convex side on the side where the metal sphere is transferred at an arbitrary temperature ( For example, it is characterized by comprising a forming plate (for example, forming plate 4) provided with a resin film 5), or
[0030]
(2)
A recess (for example, recess 4A) for receiving a metal ball (for example, metal ball 3 made of solder) is formed on the forming plate (for example, forming plate 4), and then the side on which the metal ball is transferred at an arbitrary temperature is projected. And a step of providing a resin film (for example, resin film 5) for giving warping, and then filling the recess Solder paste (For example, Sn—Pb eutectic solder paste) generating metal spheres (for example, metal spheres 3), and then planarizing and metallizing a wafer (for example, silicon wafer 1) having connection terminals (for example, connection terminals 2). A step of arranging and aligning the connection terminal and the metal sphere with the forming plate holding the sphere facing each other; and then crimping the connection terminal and the metal sphere And heating And transferring the metal spheres to the connection terminals, and then releasing the planarization of the forming plate and immersing and peeling the wafer and the forming plate in a cleaning liquid (for example, xylene). Or is characterized by
[0031]
(3)
In (2) above, the forming plate is a silicon wafer and the recess is formed by anisotropic etching of the silicon wafer, or
[0032]
(4)
In the above (2) or (3), the formation plate is flattened and the flattening is canceled by the suction and the sucking by the vacuum chuck (for example, the vacuum suction hole 11A and the vacuum source provided in the base 11). Depending on, or
[0033]
(5)
In the above (2) or (3), the flattening of the forming plate is performed by a magnet (for example, the magnet 14) set after the suction of the vacuum chuck, and the release of the flattening is performed by removing the set magnet. Or to be implemented, or
[0034]
(6)
In any one of the above (2) to (5), the formation plate is flattened or promoted for flattening while maintaining the temperature at which the resin film is flattened, or
[0035]
(7)
In any one of the above (2), (3) and (6), the resin film (for example, resin film 6: see FIG. 3) is at least two different layers (for example, polyimide films 6A and 6B: see FIG. 3). And the flattening of the forming plate and the release of the flattening are performed by maintaining the temperature at which the stress of each resin film becomes substantially equal and maintaining the temperature at which a difference appears in the stress, or
[0036]
(8)
In the above (2) or (3), the formation plate is flattened according to resin films (for example, the resin films 5A and 5B: see FIG. 2) formed on the front and back of the formation plate, and the release of the flattening is performed. Forming plate The opposite side to the recess forming surface This is performed by removing the resin film (resin film 5B: see FIG. 2).
[0037]
By adopting the above-mentioned means, after transferring the metal sphere held on the forming plate to the connection terminal of the wafer, the forming plate is warped to increase the gap with the wafer and increase the inflow amount of the cleaning liquid. It becomes possible, and the wafer and the forming plate can be easily separated. Further, when the forming plate is warped, stress is generated and peeling is promoted, and the forming plate can be peeled off faster than the case where a forming plate that does not warp is used.
[0038]
DETAILED DESCRIPTION OF THE INVENTION
4 to 7 are cutaway side views showing the main part of the forming plate and the wafer in the process steps for explaining the first embodiment of the present invention. Refer to these drawings hereinafter. I will explain. The symbols used in FIGS. 1 to 3 represent the same parts or have the same meaning.
[0039]
Refer to FIG.
4- (1)
By applying a resist process in lithography technology and a wet etching method in which the etchant is KOH, the surface index of the main surface is <110> and the diameter is about 15 [cm] (6 [inch]). The formation plate 4 made of a Si plate is anisotropically etched to receive a metal ball at a position corresponding to a connection terminal (not shown) in the wafer on which the semiconductor element is formed. A pyramid-shaped recess 4A is formed.
[0040]
4- (2)
By applying the spin coating method, the resin film 5 is formed by applying polyimide, which is a thermosetting resin capable of warping the forming plate 4 at room temperature, to the back surface of the forming plate 4.
[0041]
Specifically, the coating is described below. Polyimide is dropped on the forming plate 4 and the rotational speed is set to 500 [rpm] for 10 [seconds]. Subsequently, the rotational speed is changed to 1500 [rpm] and then 30 [seconds]. ] Was carried out each time.
[0042]
4- (3)
Pre-baking is performed for 30 minutes at a temperature of 80 ° C. to dissipate the low boiling point solvent to some extent, and then heat treatment is performed for 1 hour at a temperature of 350 ° C. to cure the resin film 5. Let The cured resin film 5 has a thickness of about 10 [μm].
[0043]
4- (4)
A resin film 5 is formed, and a forming plate 4 having a warp as shown is placed on a base 11 having a vacuum suction hole 11A.
[0044]
Refer to FIG.
4- (5)
A vacuum source (not shown) connected to the vacuum suction hole 11A, that is, a vacuum chuck is operated, and the forming plate 4 is attracted to the base 11 to be flattened.
[0045]
4- (6)
By applying the printing technique, the Sn—Pb eutectic solder paste 3A is applied so as to fill the recess 4A. Reference numeral 12 denotes a squeegee.
[0046]
Refer to FIG.
5- (1)
By heating to about 230 [° C.] and melting the solder paste 3A in the recess 4A and solidifying, the metal balls 3 made of solder are formed.
[0047]
Refer to FIG.
5- (2)
A semiconductor element is fabricated, and a wafer 1 having a connection terminal 2 is mounted on a jig (not shown) so as to face the forming plate 4, and the connection terminal 2 and the metal ball 3 are aligned. In this case, since the forming plate 4 is flattened, the alignment can be performed with high accuracy.
[0048]
Refer to FIG.
6- (1)
The connection terminal 2 of the wafer 1 and the metal sphere 3 held by the forming plate 4 are brought into contact with each other and heated to transfer the metal sphere 3 to the connection terminal 2. In this case, since the forming plate 4 is still sucked by the vacuum chuck, the entire plate cannot be put into a heating furnace. Therefore, for example, a heating means is formed on the base 11. It is necessary to.
[0049]
Refer to FIG.
6- (2)
When the suction by the vacuum chuck is released, the whole of the wafer 1 and the forming plate 4 becomes free. At this time, if the stress of the resin film 5 is large, the forming plate 4 warps, but the stress is small. Will not warp immediately, but will gradually warp as it is immersed in the cleaning liquid and the flux on the outer periphery is cleaned.
[0050]
See FIG.
7- (1)
When the whole is immersed in a cleaning solution made of xylene, a large gap is generated between the wafer 1 and the forming plate 4 due to the warp of the forming plate 4, so that the cleaning solution easily enters the wafer 1. And the forming plate 4 could be peeled off in about 20 minutes. Incidentally, in the case of using the conventional technique, it took about 2 [hour] to 3 [hour] to peel off.
[0051]
According to the first embodiment described above, the projection electrodes (bumps) made of the metal spheres 3 and having no defects can be formed on the connection terminals 2 of the wafer 1.
[0052]
FIG. 8 and FIG. 9 are main part cut side views showing a forming plate, a wafer, and the like at process points for explaining the second embodiment of the present invention. Refer to these figures hereinafter. I will explain. The symbols used in FIGS. 1 to 7 represent the same parts or have the same meaning.
[0053]
Refer to FIG.
8- (1)
In the second embodiment, the process until the forming plate 4 holding the metal ball 3 made of solder in the recess 4A is opposed to the wafer 1 having the connection terminals 2 is the same as that of the first embodiment. Omitted, the next step will be described.
[0054]
In the present embodiment, when the forming plate 4 is attracted to the base 11 having the vacuum suction hole 11A and flattened, a fixing jig plate 13 is interposed between the forming plate 4 and the base 11. The fixing jig plate 13 is mainly made of a magnetic material and can be attracted using a magnet.
[0055]
Refer to FIG.
8- (2)
The connection terminals 2 of the wafer 1 and the metal balls 3 held by the forming plate 4 are aligned and contacted to release the wafer 1 from a jig (not shown), and the magnets 14 are placed at appropriate positions. The holding jig plate 13 is sucked through the wafer 1 and the forming plate 4 so as to suppress the wafer 1 and the forming plate 4 between them.
[0056]
See FIG. 9 and FIG.
9- (1)
When the suction by the vacuum chuck is released, the wafer 1 and the forming plate 4 can be detached from the base 11 while being held by the fixing jig plate 13 and the magnet 14, and in this state, the reflow furnace The metal ball 3 is transferred to the connection terminal 2 by passing and heating.
[0057]
9- (2)
When the magnet 14 is removed, the entire wafer 1 and the forming plate 4 are released from the fixing jig plate 13 and become free, and the warping of the forming plate 4 is returned as shown in FIG. .
[0058]
9- (3)
Thereafter, as in the first embodiment, when the whole is immersed in a cleaning solution made of xylene, a large gap is generated between the wafer 1 and the forming plate 4 due to warpage of the forming plate 4. The cleaning liquid entered easily, and the wafer 1 and the forming plate 4 could be separated in about 20 minutes.
[0059]
By the way, if the formation plate 4 having the resin film 5 becomes flat or warps depending on the application temperature, it is not necessary to use a vacuum chuck or a magnet. It is necessary to control the temperature of the forming plate 4 when aligning 2 and the metal ball 3 and when immersing them in the cleaning liquid. Next, the embodiment will be described as an example.
[0060]
An example in the case of depending on temperature control will be described as a third embodiment.
(1)
Steps for forming a recess 4A for receiving a metal sphere in the forming plate 4 made of Si plate, forming a resin film 5 on the back surface of the forming plate 4, and forming a metal sphere 3 made of solder in the recess 4A. Is almost the same as in the first and second embodiments, but a vacuum chuck is not used, and a polyimide having a function of flattening the forming plate 4 at a temperature of about 100 [° C.] is used as the material of the resin film 5. It is different in that. Since a vacuum chuck is not used, it is preferable to increase the temperature to about 100 [° C.] when applying the solder paste to the recess 4A of the forming plate 4.
[0061]
(2)
Heating to about 100 [° C.] makes the forming plate 4 flat, opposes the wafer 1 having the connection terminals 2, and aligns the connection terminals 2 and the metal balls 3.
[0062]
(3)
The connection terminal 2 of the wafer 1 and the metal ball 3 held by the forming plate 4 are brought into contact with each other, and the metal ball 3 is temporarily fixed to the connection terminal 2 by performing thermocompression bonding at a temperature of 200 [° C.].
[0063]
(4)
Reflow was performed at a peak temperature of 230 [° C.], and the metal sphere 3 was completely transferred onto the connection element 2.
[0064]
(5)
When the whole is immersed in a cleaning solution made of xylene at room temperature, a gap due to warpage of the forming plate 4 is generated between the wafer 1 and the forming plate 4, so that the cleaning solution easily enters and the embodiment As in 1 and Embodiment 2, the wafer 1 and the forming plate 4 could be separated in about 20 minutes.
[0065]
Another example in the case of depending on temperature control will be described as a fourth embodiment. Here, a method of laminating two types of resin films on the forming plate 4 is adopted.
(1)
Steps for forming a recess 4A for receiving a metal sphere in the formation plate 4 made of Si plate, forming a resin film 6 on the back surface of the formation plate 4, and forming a metal sphere 3 made of solder in the recess 4A. However, the resin film 6 formed on the forming plate 4 is made of a laminate of two types of polyimide films 6A and 6B, and the characteristics are the same. This is the same as that described with reference to FIG.
[0066]
(2)
Since the two types of polyimide films 6A and 6B constituting the resin film 6 interfere with each other at room temperature, almost no warpage appears on the forming plate 4, and therefore the connecting state with the forming plate 4 is maintained as it is. The wafer 1 having the terminal 2 is opposed to the wafer 2 and the connection terminal 2 and the metal ball 3 are aligned.
[0067]
(3)
The connection terminal 2 of the wafer 1 and the metal sphere 3 held by the forming plate 4 are brought into contact with each other and heated to a temperature of 230 [° C.] to perform reflow, and the metal sphere 3 is transferred onto the connection terminal 2.
[0068]
(4)
When the whole is immersed in a cleaning solution made of xylene having a normal temperature or lower, the difference in stress between the two types of polyimide films 6A and 6B increases at a normal temperature or lower, and the warp of the forming plate 4 is between the wafer 1 and the forming plate 4. As a result, a cleaning liquid easily penetrates, and the wafer 1 and the forming plate 4 can be separated in about 20 minutes as in the first to third embodiments.
[0069]
An example will be described as Embodiment 5 without using a vacuum chuck or a magnet and requiring almost no temperature control. Here, depending on how the resin film 5 is provided, flattening and warping are realized.
(1)
A recess 4A for receiving a metal sphere is formed in the forming plate 4 made of an Si plate, and polyimide is applied to the back surface of the forming plate 4 and cured to form a resin film.
[0070]
(2)
Photosensitive polyimide is applied to the surface of the forming plate 4, a portion corresponding to the recess 4 </ b> A is exposed through an exposure mask, and development is performed to remove only the polyimide on the recess 4 </ b> A.
[0071]
(3)
The metal balls 3 are formed in the recesses 4A of the forming plate 4 in exactly the same manner as in the other embodiments. However, since the resin films are formed on both the front and back surfaces of the forming plate 4, almost no warpage occurs. Not.
[0072]
(4)
The forming plate 4 holding the metal sphere 3 and the wafer 1 having the connection terminal 2 are opposed to each other, and the connection terminal 2 and the metal sphere 3 are aligned. At this time, in order to further flatten the forming plate 4, it may be heated to about 100 [° C.].
[0073]
(5)
The connection terminal 2 of the wafer 1 and the metal sphere 3 held by the forming plate 4 are brought into contact with each other, and the metal sphere 3 is temporarily fixed to the connection terminal 2 by thermocompression bonding at a temperature of 200 [° C.].
[0074]
(6)
Reflow is performed at a peak temperature of 230 [° C.], and the metal sphere 3 is completely transferred onto the connection element 2.
[0075]
(7)
The resin film is removed by performing reactive ion etching (RIE) on the back surface of the forming plate 4 by irradiating oxygen plasma with a power of 200 [W] for 1 [hour].
[0076]
If it does in this way, a resin film will remain only on the surface side of forming board 4, and curvature will generate | occur | produce due to the stress.
[0077]
(8)
When the whole is immersed in a cleaning solution made of xylene, a gap is generated between the wafer 1 and the forming plate 4 due to the warp of the forming plate 4, so that the cleaning solution easily enters and other implementations are performed. As in the first embodiment, the wafer 1 and the forming plate 4 could be peeled off in about 20 minutes.
[0078]
The present invention is not limited to the above-described embodiment, and many other modifications can be realized. For example, in each of the above embodiments, a resin film that warps a forming plate Although polyimide is used as the material, it can be replaced with other materials such as epoxy and Si coupling material.
[0079]
Specific examples of the Si coupling material include:
γ-glycidoxypropyltrimethoxysilane
γ-glycidoxypropyltriethoxysilane
γ-aminopropyltrimethoxysilane
γ-aminopropyltriethoxysilane
Vinyltriethoxysilane
Vinyltrimethoxysilane
γ-mercaptopropyltrimethoxysilane
γ-mercaptopropyltriethoxysilane
Etc.
[0080]
In the above embodiment, a silicon wafer is used as the forming plate. However, this can be replaced with a glass wafer or a resin wafer having warpage at an arbitrary temperature. Can also be formed by vapor deposition. However, in the case of applying the vapor deposition method, for example, a metal mask is applied to a silicon wafer, and a mother alloy such as solder in a crucible is blown in a vacuum furnace to be deposited on the silicon wafer. Therefore, it is not a sphere but a truncated cone shape.
[0081]
Furthermore, although the case where the metal material filling the recess is Sn—Pb eutectic solder has been described, other general solders such as Sn-3.5Ag, Sn-3.3Ag-3Bi-0. You may employ | adopt suitably, such as 5Cu.
[0082]
【The invention's effect】
In the bump electrode forming substrate and the bump electrode forming method using the same according to the present invention, the formation of the resin film which holds the metal sphere and gives the warp with the metal sphere transfer side convex. When a wafer having a connection terminal is opposed to the plate and the connection terminal and the metal sphere are aligned, the formation plate is flattened, and after the metal sphere is transferred to the connection terminal, the substrate is immersed in a cleaning solution. When peeling off, a warp is generated in the forming plate.
[0083]
By adopting the above configuration, after transferring the metal spheres held on the forming plate to the connection terminals of the wafer, the forming plate is warped to increase the gap with the wafer and increase the inflow amount of the cleaning liquid. It becomes possible, and the wafer and the forming plate can be easily separated. Further, when the forming plate is warped, stress is generated and peeling is promoted, and the forming plate can be peeled off faster than the case where a forming plate that does not warp is used.
[Brief description of the drawings]
FIG. 1 is a cutaway side view of a main part showing a forming plate and a resin film holding metal balls for explaining the characteristics of various resin films.
FIG. 2 is a cutaway side view of an essential part showing a forming plate and a resin film holding metal balls for explaining the characteristics of various resin films.
FIG. 3 is a main part explanatory view showing resin film and data for explaining characteristics of the resin film.
FIG. 4 is a cutaway side view of a main part showing a forming plate, a wafer, and the like at process points for explaining the first embodiment in the present invention.
FIG. 5 is a cutaway side view of a main part showing a forming plate, a wafer, and the like at process key points for explaining the first embodiment of the present invention.
FIG. 6 is a cutaway side view of a main part showing a forming plate, a wafer, and the like at process points for explaining the first embodiment of the present invention.
FIG. 7 is a cutaway side view of a main part showing a forming plate, a wafer, and the like at process key points for explaining the first embodiment of the present invention.
FIG. 8 is a cutaway side view of a main part showing a forming plate, a wafer, and the like at process points for explaining a second embodiment of the present invention.
FIG. 9 is a cutaway side view of a main part showing a forming plate, a wafer, and the like at process points for explaining Embodiment 2 of the present invention.
FIG. 10 is a cutaway explanatory view of a main part showing a wafer or the like at a process point for explaining an example in the prior art.
FIG. 11 is a cutaway explanatory view of a main part showing a wafer or the like at a process point for explaining an example in the prior art.
[Explanation of symbols]
1 Wafer
2 connection terminals
3 Metal balls
3A Sn-Pb eutectic solder paste
4 Forming plate
4A recess
5 Resin film
5A resin film
5B resin film
6 Resin film
6A resin film
6B Resin film
11 base
11A Vacuum suction hole
12 Squeegee
13 Fixing jig plate
14 Magnet

Claims (8)

Protrusion electrode formation comprising a forming plate provided with a resin film provided with a recess for receiving a metal sphere and provided with a warp with the metal sphere transfer side convex at an arbitrary temperature Substrate. A step of forming a recess for receiving the metal sphere in the forming plate and then providing a resin film for giving a warp with the convex side of the metal sphere transferred at an arbitrary temperature;
Next, a step of generating a metal sphere from the solder paste filling the recess,
Next, arranging and aligning the wafer having the connection terminals and the forming plate holding the metal balls flattened with the connection terminals facing the metal balls; and
Next, the step of crimping and heating the connection terminal and the metal sphere to transfer the metal sphere to the connection terminal;
And a step of releasing the planarization of the forming plate and immersing and peeling the wafer and the forming plate in a cleaning solution. 3. The protruding electrode forming method according to claim 2, wherein the forming plate is a silicon wafer and the recess is formed by anisotropic etching of the silicon wafer. 4. The method for forming a protruding electrode according to claim 2, wherein the flattening of the forming plate and the release of the flattening depend on suction by a vacuum chuck and release of the suction. The flattening of the forming plate is performed by a magnet set after suction of the vacuum chuck, and the release of the flattening is performed by removing the set magnet. Method for forming protruding electrode. 6. The method for forming a bump electrode according to claim 2, wherein the forming plate is flattened or promoted for flattening while maintaining a temperature at which the resin film is flattened. The resin film is composed of at least two different layers, and flattening of the forming plate and release of flattening are performed by maintaining the temperature at which the stress of each resin film becomes substantially equal and maintaining the temperature at which the difference in stress appears. The method for forming a protruding electrode according to any one of claims 2, 3, and 6. The flattening of the forming plate should be performed by the resin film formed on the front and back of the forming plate, and the release of the flattening should be performed by removing the resin film on the opposite side of the forming surface of the forming plate. The method for forming a protruding electrode according to claim 2, wherein:

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