JP2013086236A - Method for forming through hole in insulating substrate and method for manufacturing insulating substrate for interposer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method in which dislocation hardly occurs in a formation position when forming a plurality of through holes in an insulating substrate.SOLUTION: When forming the plurality of through holes in the insulating substrate using laser guiding type electric discharge technology, the through holes are formed from an objective position that is a centermost position and then positions for forming the through holes are expanded outward.

Description

  The present invention relates to a method of forming a through hole in an insulating substrate, which is used when manufacturing an interposer or the like.

  Conventionally, a method for manufacturing a substrate for an interposer by forming a plurality of through holes (vias) by irradiating an insulating substrate with laser light has been disclosed (for example, Patent Document 1).

  Recently, a technique for making a through hole in an insulating substrate using an electric discharge machining technique (laser induction type electric discharge machining technique) has been disclosed (for example, Patent Document 2). In this method, after heating a desired position of the insulating substrate using laser light, the heated position is melted by induction discharge, and the molten material is removed. In this method, it is disclosed that a through hole can be formed in an insulating substrate more quickly than a method using only laser light.

International Publication No. WO2010 / 087483 International Publication No. WO2011 / 038788

  As described above, with the laser induction type electric discharge machining technique, it is possible to quickly form a through hole in the insulating substrate.

  However, this method has a feature that heat is easily accumulated locally on the insulating substrate. For this reason, when a plurality of through holes are sequentially formed in the insulating substrate, there is a problem that the insulating substrate is deformed during the formation process of the through holes. Furthermore, if such deformation occurs in the insulating substrate during the formation process of the through hole, the formation position of the through hole is shifted from the desired position during the subsequent formation process of the through hole, and the accurate position is obtained. The problem that it becomes difficult to form a through-hole may arise.

  The present invention has been made in view of such a problem. In the present invention, when a plurality of through holes are formed in an insulating substrate using a laser induction electric discharge machining technique, the position of the through holes is shifted. The purpose is to provide a method that is unlikely to occur. Another object of the present invention is to provide a method for manufacturing an insulating substrate for an interposer that is less likely to be displaced in the formation position of the through hole.

In the present invention, a method of forming a plurality of through holes in an insulating substrate using laser induction discharge technology,
(I) preparing an insulating substrate;
(Ii) sequentially forming a total of n (where n is an integer of 9 or more) through holes on the surface of the insulating substrate at a constant pitch P in the horizontal X direction and the vertical Y direction;
Have
The step (ii)
(A) Of the n target positions where the through-hole is formed, when the target position at the center is one, the target position is referred to as the center position,
(B) Of the n target positions in which the through hole is formed, when there are two or more target positions at the center, the target positions are referred to as a central target position group,
The center position or the center object in a quadrilateral composed of two sides parallel to the horizontal X direction and two sides parallel to the vertical Y direction with the four target positions selected from the target positions as vertices When the smallest rectangle including the position group is drawn, the target positions located on the four sides and the four vertices of the rectangle are defined as the first target position group,
The first target position group is a quadrilateral composed of two side parallel to the horizontal X direction and two sides parallel to the vertical Y direction with the four target positions selected from the target positions as vertices. When the smallest rectangle included inside is drawn, the target positions located on the four sides and the four vertices of the square are set as the second target position group,
Similarly,
The (k-1) th object is a quadrangle formed by two object positions selected from the object positions as vertices and having two sides parallel to the horizontal X direction and two sides parallel to the vertical Y direction. When the smallest rectangle including the position group is drawn, and the target positions located on the four sides and the four vertices of the rectangle are the k-th target position group (where k is an integer of 2 or more),
(B1) First, a step of forming a through hole in all the target positions belonging to the central position or the central target position group;
(B2) Next to the step (b1), a step of forming through holes in all the target positions belonging to the first target position group;
...
(Bk) Next to the step (b (k-1)), a step of forming through holes in all the target positions belonging to the k-th target position group;
Is provided.

  Here, in the method according to the present invention, the order in which the through holes are formed at the n target positions may be spiral.

  Further, in the method according to the present invention, the time from when a through hole is formed at one target position to when the through hole is formed at the next target position may be in the range of 1 msec to 2 msec.

  In the method according to the present invention, the diameter of each through hole may be in the range of 5 μm to 200 μm.

  In the method according to the present invention, the insulating substrate may have a thickness in the range of 0.03 mm to 1.0 mm.

  In the method according to the present invention, the pitch P may be in the range of 30 μm to 500 μm.

In the method according to the present invention, the through-hole density on the surface of the insulating substrate may be in the range of 1000 / cm ^{2 to} 2000 / cm ² .

Furthermore, the present invention is a method of manufacturing an insulating substrate for an interposer having a plurality of through holes using laser induced discharge technology,
(I) preparing an insulating substrate;
(Ii) sequentially forming a total of n (where n is an integer of 9 or more) through holes on the surface of the insulating substrate at a constant pitch P in the horizontal X direction and the vertical Y direction;
Have
The step (ii)
(A) Of the n target positions where the through-hole is formed, when the target position at the center is one, the target position is referred to as the center position,
(B) Of the n target positions in which the through hole is formed, when there are two or more target positions at the center, the target positions are referred to as a central target position group,
The center position or the center object in a quadrilateral composed of two sides parallel to the horizontal X direction and two sides parallel to the vertical Y direction with the four target positions selected from the target positions as vertices When the smallest rectangle including the position group is drawn, the target positions located on the four sides and the four vertices of the rectangle are defined as the first target position group,
The first target position group is a quadrilateral composed of two side parallel to the horizontal X direction and two sides parallel to the vertical Y direction with the four target positions selected from the target positions as vertices. When the smallest rectangle included inside is drawn, the target positions located on the four sides and the four vertices of the square are set as the second target position group,
Similarly,
The (k-1) th object is a quadrangle formed by two object positions selected from the object positions as vertices and having two sides parallel to the horizontal X direction and two sides parallel to the vertical Y direction. When the smallest rectangle including the position group is drawn, and the target positions located on the four sides and the four vertices of the rectangle are the k-th target position group (where k is an integer of 2 or more),
(B1) First, a step of forming a through hole in all the target positions belonging to the central position or the central target position group;
(B2) Next to the step (b1), a step of forming through holes in all the target positions belonging to the first target position group;
...
(Bk) Next to the step (b (k-1)), a step of forming through holes in all the target positions belonging to the k-th target position group;
Is provided.

  In the present invention, when a plurality of through holes are formed in an insulating substrate by using a laser induction type electric discharge machining technique, a method can be provided in which the formation positions of the through holes are not easily displaced. In addition, the present invention can provide a method for manufacturing an insulating substrate for an interposer that hardly causes a shift in the formation position of the through hole.

It is the figure which showed an example of the structure of the laser induction type electric discharge machining apparatus utilized for a laser induction type electric discharge machining technique. It is the figure which showed typically the mode at the time of forming the several through-holes 185P and 185Q in the insulated substrate 180 using the laser induction type electric discharge machining apparatus 100 shown in FIG. It is the schematic diagram which expanded and showed the insulated substrate and its vicinity at the time of forming a through-hole in an insulated substrate using the laser induction type electrical discharge machining apparatus shown in FIG. 4 is a partial top view of an insulating substrate 180. FIG. It is the schematic diagram which expanded and showed the insulated substrate and its vicinity in the middle of forming a several through-hole in an insulated substrate by the conventional method. It is the schematic diagram which expanded and showed the insulated substrate and its vicinity in the middle of forming a several through-hole in an insulated substrate by the conventional method. 4 is a partial top view of an insulating substrate 180. FIG. It is the schematic diagram which expanded and showed the insulated substrate and its vicinity in the middle of forming the several through-hole in an insulated substrate by the method of this invention. 4 is a partial top view of an insulating substrate 180. FIG. It is a schematic flow diagram of an example of a method for manufacturing an insulating substrate for an interposer according to the present invention.

  Hereinafter, the present invention will be described with reference to the drawings.

(Laser induction type electric discharge machining technology)
First, the laser induction type electric discharge machining technique used in the present invention will be briefly described.

  In the present application, the “laser induction type electric discharge machining technology” means a technique for forming a through hole in a workpiece by combining laser light irradiation on the workpiece and an interelectrode discharge phenomenon as shown below. It means the generic name.

  FIG. 1 schematically shows an example of a configuration of a laser induction type electric discharge machining apparatus used in laser induction type electric discharge machining technology.

  As shown in FIG. 1, the laser induction type electric discharge machining apparatus 100 includes a laser light source 110, a high-frequency and high-voltage power supply 130, a DC high-voltage power supply 140, a switching unit 150, and a pair of electrodes 160A and 160B.

  The laser light source 110 is not limited to this, but is, for example, a carbon dioxide laser having an output of 1 W to 100 W, and can form a focal spot in the range of 10 μm to 50 μm, for example, on the workpiece.

  The electrodes 160A and 160B are electrically connected to the conductors 162A and 162B, respectively. These conductors 162A and 162B are connected to the high-frequency high-voltage power supply 130 and the DC high-voltage power supply 140 via the switching unit 150. Yes.

  The switching unit 150 has a role of switching the connection destination of the conductors 162A and 162B between the high-frequency high-voltage power supply 130 / DC high-voltage power supply 140.

  When forming a through-hole using such a laser induction type electric discharge machining apparatus 100, an insulating substrate 180 to be processed is disposed between the electrodes 160A and 160B. The distance between the electrodes is usually about 1 mm. Further, by moving a stage (not shown) in the horizontal direction, the insulating substrate 180 is disposed at a predetermined position with respect to the electrodes 160A and 160B.

  Next, the laser light 113 is irradiated from the laser light source 110 to the target position (through hole forming position). Thereby, the temperature of the irradiation position 183 of the laser beam 113 on the insulating substrate 180 increases.

  Within a short time after the irradiation with the laser beam 113, the switching unit 150 connects the conductors 162A and 162B to the high-frequency high-voltage power supply 130, thereby generating a high-frequency high-voltage discharge between the electrodes 160A and 160B. Discharge just occurs at the irradiation position 183 of the laser beam 113. This is because, at this position, the temperature is locally increased by the irradiation of the laser beam 113, and the resistance of the insulating substrate is lower than that of other portions.

  Due to the discharge between the electrodes 160A and 160B, large energy is applied to the irradiation position 183 of the insulating substrate 180, and the insulating substrate 180 is locally melted.

  Next, the switching unit 150 connects the conductors 162A and 162B to the DC high-voltage power supply 140, and a high DC voltage is applied between the electrodes 160A and 160B. As a result, the melt at the irradiation position 183 of the insulating substrate 180 is removed, and a through hole 185 is formed at a desired position of the insulating substrate 180.

  It is obvious to those skilled in the art that the laser induction type electric discharge machining apparatus 100 shown in FIG. 1 is an example, and a laser induction type electric discharge machining apparatus having another configuration may be used.

  FIG. 2 is a diagram schematically showing a state in which a plurality of through holes 185P and 185Q are sequentially formed in the insulating substrate 180 using the laser induction type electric discharge machining apparatus 100 shown in FIG. is there.

  As shown in FIG. 2, when forming a plurality of through holes in the insulating substrate 180, first, the first through holes 185P are formed in the insulating substrate 180 by the above-described operation.

  Next, the positions of the electrodes 160 </ b> A and 160 </ b> B are shifted with respect to the insulating substrate 180 in accordance with the formation pitch P of the through holes. Then, the same operation as that for forming the first through hole 185P is performed, and the second through hole 185Q is formed. In a normal case, the pitch P between the through holes 185P and 185Q is relatively narrow, for example, about 100 μm at the maximum.

  FIG. 3 is an enlarged schematic cross-sectional view showing the insulating substrate 180 and its vicinity when the through hole is formed using the laser induction type electric discharge machining apparatus 100 as described above.

  As shown in FIG. 3, the insulating substrate 180 is placed on the stage 190 before processing. The stage 190 has a “frame” shape with a hollow central portion, and the hollow portion 192 serves as a processing region. That is, in the insulating substrate 180, the through hole 185 is formed in a region corresponding to the hollow portion 192 of the stage 190. Note that the periphery of the insulating substrate 180 is restrained by the restraining member 210 in order to prevent displacement.

  Here, when the through hole is formed in the insulating substrate using the laser induction type electric discharge machining technique as described above, there is a problem that heat is likely to be locally accumulated in the insulating substrate. For this reason, when the plurality of through holes 185 are sequentially formed in the insulating substrate 180, there may be a problem that the insulating substrate 180 is deformed during the formation process of the through holes. Furthermore, if such deformation occurs in the insulating substrate 180 during the through hole forming process, the through hole forming position is shifted from the desired position during the subsequent through hole forming process, and the accurate position is determined. This may cause a problem that it is difficult to form a through hole.

  This problem will be described in detail with reference to FIGS.

  FIG. 4 shows a partial top view of the insulating substrate 180. In FIG. 4, the positions (1, 1) to (5, 5) of ◯ indicate positions where through holes are formed. The positions (1, 1) to (5, 5) are arranged on the XY plane at a constant pitch P.

  Here, when forming the through hole, as shown by the arrow in the upper right frame of FIG. 4, the position (1, 1) is set as the start position, and the position (2, 1) is sequentially formed along the direction of the arrow. , Position (3,1), position (4,1), and position (5,1) and through holes, then position (5,2), position (4,2), position (3,2 ), Position (2, 2), and position (1, 2) and through-holes are formed, then position (1, 3), position (2, 3), position (3, 3), position (4 , 3) and position (5, 3) and through holes, then position (5, 4), position (4, 4), position (3,4), position (2, 4), and position (1,4) and a through hole are formed, and further, position (1,5), position (2,5), position (3,5), position (4,5), and position (5,5) and through Consider the case of forming a hole.

  In this case, as shown in FIG. 4, the order in which the through holes are formed is that the position (1, 1) is the first (185-1) and the position (2, 1) is the second (185-2). ) And the position (5, 5) is the 25th (185-25).

  In order to form a plurality of through holes in the insulating substrate 180 in this order, for example, at the stage where the fifteenth through hole 185-15 is formed, the upper side of the surface of the insulating substrate 180 in FIG. Heat is accumulated in the portions (1, 1) to (5, 1), positions (1, 2) to (5, 2), and positions (1, 3) to (5, 3). . Therefore, the insulating substrate 180 is deformed in the middle of the process.

  5 and 6 are schematic cross-sectional views of the insulating substrate 180 when viewed from the direction of the arrow 410 in FIG. 4 at the stage where the fifteenth through-hole 185-15 is formed.

  5 and 6, the through hole 185A corresponds to the through holes 185-1 to 185-5 formed at the positions (1, 1) to (5, 1) in FIG. 4, and the through hole 185B 4 corresponds to the through holes 185-6 to 185-10 formed at positions (1, 2) to (5, 2) in FIG. 4, and the through holes 185C correspond to the positions (1, 3) to (5, 3 in FIG. Corresponds to the through-holes 185-11 to 185-15 formed in (1).

  In the example shown in FIG. 5, the right side portion of the insulating substrate 180 is deformed and protrudes upward. Since this deformed portion corresponds to the region where the formation of the through hole has been completed, it will be hereinafter referred to as a “through hole formation completed region” and represented by reference numeral 430. On the other hand, the left side portion of the insulating substrate 180 that has not been deformed corresponds to a region where the formation of the through hole is not completed, and is hereinafter referred to as a “through hole formation incomplete region” and denoted by reference numeral 440. To do.

  On the other hand, in the example shown in FIG. 6, the insulating substrate 180 is deformed such that the right side portion protrudes upward and the left side portion protrudes downward. That is, the “through-hole formation completion region” 430 protrudes upward, and the “through-hole formation incomplete region” 440 protrudes downward.

  Here, in the middle of the formation of the through hole, the insulating substrate 180 is deformed as shown in FIG. 5, that is, the “through hole formation completed region” 430 protrudes upward, and the “through hole formation incomplete region” 440 is flat. In the case where such deformation remains, it is unlikely that the formation position of the through hole is shifted from the desired position in the subsequent through hole formation process in the “through hole formation incomplete region” 440.

  On the other hand, in the middle of the formation of the through hole, the insulating substrate 180 is deformed as shown in FIG. 6, that is, the “through hole formation completion region” 430 protrudes upward, and the “through hole formation incomplete region” 440 In the case where a deformation that protrudes downward occurs, in the subsequent through-hole formation process in the “through-hole formation incomplete region” 440, there is a high possibility that the formation position of the through-hole is shifted from a desired position.

  It should be noted that whether the deformation of the insulating substrate 180 in FIG. 5 or FIG. 6 depends on slight variations in process conditions or the like, and therefore the deformation of the insulating substrate is predicted in advance. It ’s difficult.

  In addition, when sequentially forming a plurality of through holes in the insulating substrate, the positions of the electrode pairs with respect to the insulating substrate at the time of forming each through hole are programmed in advance, and based on this program, the electrodes or It is common to perform an operation of moving the insulating substrate. However, if the deformation mode of the insulating substrate cannot be predicted, such programming cannot be performed. In addition, when programming is performed based on one of the deformation modes of FIGS. 5 and 6, when a deformation different from the predetermined mode occurs, a through hole is formed in the “through hole formation incomplete region”. When forming, a positional deviation from a desired position occurs.

  In general, the distance between the electrodes 160A and 160B is extremely narrow, about 1 mm to 2 mm. For this reason, as a deformation mode of the insulating substrate 180, when a through hole forming process is performed by predicting the deformation as shown in FIG. 5, if the deformation of the mode as shown in FIG. May collide with the insulating substrate 180. Conversely, when the deformation of the embodiment as shown in FIG. 5 occurs even though the deformation of the embodiment as shown in FIG. Can occur.

  The inventors of the present application have recognized the problem of displacement of the through-hole formation position due to the deformation of the insulating substrate and the problem regarding the collision of the electrodes, and have studied a measure for reducing this problem. As a result, the inventors have found that the problem of positional deviation and / or collision between the electrode and the insulating substrate is significantly suppressed by setting the order of formation of the through holes to a predetermined order, and the present invention has been achieved.

That is, in the present invention,
A method of forming a plurality of through holes in an insulating substrate using laser induced discharge technology,
(I) preparing an insulating substrate;
(Ii) sequentially forming a total of n (where n is an integer of 9 or more) through holes on the surface of the insulating substrate at a constant pitch P in the horizontal X direction and the vertical Y direction;
Have
The step (ii)
(A) Of the n target positions where the through-hole is formed, when the target position at the center is one, the target position is referred to as the center position,
(B) Of the n target positions in which the through hole is formed, when there are two or more target positions at the center, the target positions are referred to as a central target position group,
The center position or the center object in a quadrilateral composed of two sides parallel to the horizontal X direction and two sides parallel to the vertical Y direction with the four target positions selected from the target positions as vertices When the smallest rectangle including the position group is drawn, the target positions located on the four sides and the four vertices of the rectangle are defined as the first target position group,
The first target position group is a quadrilateral composed of two side parallel to the horizontal X direction and two sides parallel to the vertical Y direction with the four target positions selected from the target positions as vertices. When the smallest rectangle included inside is drawn, the target positions located on the four sides and the four vertices of the square are set as the second target position group,
Similarly,
The (k-1) th object is a quadrangle formed by two object positions selected from the object positions as vertices and having two sides parallel to the horizontal X direction and two sides parallel to the vertical Y direction. When the smallest rectangle including the position group is drawn, and the target positions located on the four sides and the four vertices of the rectangle are the k-th target position group (where k is an integer of 2 or more),
(B1) First, a step of forming a through hole in all the target positions belonging to the central position or the central target position group;
(B2) Next to the step (b1), a step of forming through holes in all the target positions belonging to the first target position group;
...
(Bk) Next to the step (b (k-1)), a step of forming through holes in all the target positions belonging to the k-th target position group;
Is provided.

  Hereinafter, the effects of the present invention will be described with reference to FIGS.

  FIG. 7 is a partial top view of the insulating substrate 180 similar to FIG. In FIG. 7, the positions (1, 1) to (5, 5) of ◯ indicate positions where through holes are formed. The positions (1, 1) to (5, 5) are arranged on the XY plane at a constant pitch P (for example, 100 μm) in the X direction and the Y direction.

  Here, in the case of FIG. 7, the order in which the through holes are formed is different from the case of FIG. That is, in the through hole, the center position (3, 3) is the first (185-1), the position (3, 2) is the second (185-2), and the position (4, 2) is the second. 3rd (185-3), position (4,3) is 4th (185-4), position (4,4) is 5th (185-5), and position (3,4) is 6th (185-6), position (2, 4) becomes 7th (185-7), position (2, 3) becomes 8th (185-8), position (2, 2) Becomes the ninth (185-9), the position (2,1) becomes the tenth (185-10), the position (3,1) becomes the eleventh (185-11), and the position (4,1 ) Becomes the 12th (185-12), the position (5, 1) becomes the 13th (185-13), and the position (5, 2) becomes the 14th. 185-14), the position (5, 3) is the fifteenth (185-15), the position (5, 4) is the sixteenth (185-16), and the position (5, 5) is the seventeenth. (185-17), position (4, 5) is the 18th (185-18), position (3, 5) is the 19th (185-19), and position (2, 5) is the 20th. Position (185-20), position (1, 5) is 21st (185-21), position (1, 4) is 22nd (185-22), and position (1, 3) is position 21 23rd (185-23), position (1,2) is 24th (185-24), and position (1,1) is 25th (185-25). .

  That is, in the case of FIG. 7, the through holes are formed in the “spiral” order as shown in the upper right frame of the drawing.

  FIG. 8 is a schematic cross-sectional view of the insulating substrate 180 when viewed from the direction of the arrow 410 in FIG. 7 at the stage where the ninth through-hole 185-9 is formed at the position (2, 2). Show.

  8, the through hole 185D corresponds to the through holes 185-1, 185-4, and 185-8 formed at the positions (3, 3), (4, 3), and (2, 3) in FIG. The through hole 185E corresponds to the through holes 185-2, 185-3 and 185-9 formed at the positions (3, 2), (4, 2) and (2, 2) in FIG. The hole 185F corresponds to the through holes 185-5, 185-6, and 185-7 formed at the positions (4, 4), (3,4), and (2, 4) in FIG.

  As shown in FIG. 8, in this case, in the middle of the formation of the through hole, the insulating substrate 180 is deformed such that the “through hole formation completion region” 430, that is, the central portion of the insulating substrate 180 protrudes upward. However, the “through hole formation incomplete region” 440, that is, both end portions of the insulating substrate 180 remain substantially flat. In this case, the “through hole formation incomplete region” 440 is unlikely to deform so as to protrude downward. Therefore, when the through holes are formed in the order as shown in FIG. 7, the deformation mode of the insulating substrate becomes almost constant every time. For this reason, it is possible to accurately determine the formation position of each through hole in consideration of deformation of the insulating substrate.

  As described above, when the through holes are formed in the order as shown in FIG. 7, the through hole formation position deviates from a desired position in the subsequent through hole formation process in the “through hole formation incomplete region” 440. It becomes possible to reduce the problem.

  Further, when the deformation as shown in FIG. 8 always occurs, the problem that the insulating substrate 180 collides with the electrodes 160A and 160B is reduced. This is because the positions of the electrodes 160A and 160B in the vertical direction can be adjusted in advance based on the deformation amount.

  As described above, according to the present invention, when a plurality of through holes are formed in the insulating substrate using the laser induction type electric discharge machining technique, it is possible to provide a method in which the formation position of the through holes is not easily shifted. . Further, according to the present invention, it is possible to provide a method in which the problem of collision between the electrode and the insulating substrate is reduced.

  It should be apparent to those skilled in the art that the through hole formation order shown in FIG. 7 is merely an example.

  That is, according to the present invention, the formation order of the through holes when forming the through holes at a constant pitch P in the X and Y directions on the XY plane can be expressed as follows.

When there is one target position at the center among n target positions where the through hole is formed, the target position is referred to as a “center position”, and the XY coordinates of the “center position” are (i, j) When
A square having four points at the target positions represented by coordinates (i-1, j-1), coordinates (i-1, j + 1), coordinates (i + 1, j-1), and coordinates (i + 1, j + 1). The target positions located on the four sides and the four vertices of the square are defined as “first target position group”,
A square having four points at the target positions represented by coordinates (i−2, j−2), coordinates (i−2, j + 2), coordinates (i + 2, j−2), and coordinates (i + 2, j + 2). The target positions located on the four sides and the four vertices of the square are defined as “second target position group”,
Similarly,
A square having apexes at four points of the target position represented by coordinates (i−k, j−k), coordinates (i−k, j + k), coordinates (i + k, j−k), and coordinates (i + k, j + k) In the case where the target positions located on the four sides and the four vertices of the square are the “kth target position group”,
(1) First, a through hole is formed at the center position,
(2) After the step (1), through holes are formed in all the target positions belonging to the first target position group,
...
(K) After the step (k-1), through holes are formed in all the target positions belonging to the k-th target position group.

  By forming the through holes in this order, the effects of the present invention as described above can be obtained.

  In the above description, a case where a single target position, that is, a “center position” exists at the “center” of all target positions where the through holes are formed has been described as an example. For example, as shown in FIG. 7, in the example where the through holes are formed in a 5 × 5 matrix, the “center position” of all the target positions is the position (3, 3). For example, when the through holes are formed in a 3 × 3 matrix, the coordinates of the “center position” of all target positions are (2, 2).

  However, there may be a plurality of target positions at the “center” of all target positions where the through holes are formed.

  Hereinafter, with reference to FIG. 9, the formation order of the through holes in such a case will be described.

  FIG. 9 is a partial top view of the insulating substrate 180 similar to FIG. In FIG. 9, the positions (1, 1) to (4, 4) of ◯ indicate positions where through holes are formed. The positions (1, 1) to (4, 4) are arranged on the XY plane at a constant pitch P (for example, 100 μm) in the X direction and the Y direction.

  In such an arrangement in which the through holes are formed in a 4 × 4 matrix, there is no so-called mathematical “center” target position on the surface of the insulating substrate 180. Therefore, in the present invention, in such a case, among the target positions where the through holes are formed, a plurality of target positions at the center are represented as “a group of central objects”.

  When such a “group of central objects” exists, this “group of central objects” is handled in the same manner as the above-mentioned “center position”, and the formation order of each through hole is determined, thereby An effect can be obtained.

  For example, in the case of the through-hole arrangement shown in FIG. 9, the position (2, 2), the position (3, 2), the position (2, 3), and the position (3, 3) are “a group of central objects”. Further, the remaining target positions surrounding the “central target group” constitute a “first target position group”.

  Therefore, in the case of the through-hole arrangement shown in FIG. 9, the through-hole is, for example, the position (2, 3) of the “center object group” is the first (185-1) and the position (2, 2) is the first. 2nd (185-2), position (3,2) is 3rd (185-3), and position (3,3) is 4th (185-4) (hereinafter “central object group”) Next, the position (3, 4) is the fifth (185-5), the position (2, 4) is the sixth (185-6), and the position (1, 4) is the seventh (185). -7), the position (1,3) is the eighth (185-8), the position (1,2) is the ninth (185-9), and the position (1,1) is the tenth ( 185-10), position (2,1) becomes the eleventh (185-11), position (3,1) becomes the twelfth (185-12) Position (4, 1) is the thirteenth (185-13), position (4, 2) is the fourteenth (185-14), and position (4, 3) is the fifteenth (185-15). The position (4, 4) may be formed so as to be the 16th (185-16) (hereinafter referred to as “first target position group”).

  It will be apparent to those skilled in the art that the “group of central objects” is defined in the same procedure in the arrangement of the through holes other than FIG. For example, in the case of an arrangement in which the through holes are formed in a 3 × 4 (or 4 × 3) matrix, the two most central target positions are selected as the “center target group”.

To summarize the above discussion, when the through holes are formed at a constant pitch P in the X direction and the Y direction on the XY plane, the formation order of the through holes in the present invention is determined as follows:
In a quadrangle composed of two sides parallel to the horizontal X direction and two sides parallel to the vertical Y direction, with four target positions selected from n target positions where through-holes are formed as apexes , When the smallest square including “center position” or “center target position group” is drawn, the target positions located on the four sides and four vertices of the square are defined as the first target position group,
The first target position group is a quadrilateral composed of two side parallel to the horizontal X direction and two sides parallel to the vertical Y direction with the four target positions selected from the target positions as vertices. When the smallest rectangle included inside is drawn, the target positions located on the four sides and the four vertices of the square are set as the second target position group,
Similarly,
The (k-1) th object is a quadrangle formed by two object positions selected from the object positions as vertices and having two sides parallel to the horizontal X direction and two sides parallel to the vertical Y direction. When the smallest rectangle including the position group is drawn, and the target positions located on the four sides and the four vertices of the rectangle are the k-th target position group (where k is an integer of 2 or more),
(1) First, a step of forming through holes in all the target positions belonging to the central position or the central target position group;
(2) After the step of (1), a step of forming through holes in all target positions belonging to the first target position group;
...
(K) Next to the step (k-1), forming a through hole in all the target positions belonging to the k-th target position group;
A method comprising the steps of:

  Here, the expression “with a (including target position group) rectangle” means that all positions of the target “target position group” exist inside the rectangle, and the target “target It should be noted that any position in the “position group” does not include the case where the position is on the vertex and each side of the rectangle. For example, in FIG. 9, a quadrangle having four vertices at position (1, 2), position (4, 2), position (4, 4) and position (1, 4) is represented by position (2, 2) and position ( 3 and 2) are present on that side, and therefore do not include the “central object group” inside. Therefore, the four vertices of the rectangle and the positions on each side do not constitute the first target position group.

  Note that the order in which the through holes are formed is not particularly limited for each target position in the “group of central objects”. The same applies to each target position in the same “kth target position group”. However, as shown in FIGS. 7 and 9, when the through holes are formed in an order that spirally spreads outward from the center side, the positions of the electrodes 160A and 160B with respect to the insulating substrate 180 are not moved much. Therefore, the through hole can be formed more efficiently.

(Method of manufacturing an insulating substrate for an interposer)
Next, with reference to FIG. 10, a method for manufacturing an insulating substrate for an interposer according to the present invention will be described.

  FIG. 10 shows an example of a schematic flow diagram of a method for manufacturing an insulating substrate for an interposer according to the present invention.

As shown in FIG. 10, a method for manufacturing an insulating substrate for an interposer according to the present invention includes:
(A) a step of preparing an insulating substrate (step S110);
(B) A step of sequentially forming a total of n (where n is an integer of 9 or more) through holes on the surface of the insulating substrate at a constant pitch P in the horizontal X direction and the vertical Y direction (step S120). )When,
Have

  Hereinafter, each step will be described in detail.

(Step S110)
First, an insulating substrate for an interposer is prepared.

  The material of the insulating substrate is not particularly limited. The insulating substrate may be a glass substrate such as soda lime glass, for example.

  Further, the thickness of the insulating substrate is not particularly limited. The thickness of the insulating substrate may be, for example, in the range of 0.03 mm to 0.5 mm. As the thickness of the insulating substrate is reduced, the formation time of the through hole can be shortened, but handling becomes complicated.

(Step S120)
Next, a plurality of through holes are formed in the insulating substrate prepared in step S110 by using laser induction discharge technology.

  The laser induction discharge technology to be applied is not particularly limited, but a plurality of through holes may be formed in the insulating substrate using, for example, an apparatus as shown in FIG.

  The laser beam used may be a carbon dioxide laser. Further, the output of the laser beam may be, for example, in the range of 1W to 100W. Furthermore, the spot diameter of the laser beam may be in the range of 10 μm to 50 μm, for example. However, the spot shape of the laser beam may be a shape other than a circular shape, for example, an elliptical shape. Note that laser light may be emitted from both sides of the insulating substrate.

  The high frequency high voltage power supply used may have a frequency of 1 MHz to 100 MHz. The DC high-voltage power supply used may be a power supply that can apply a DC voltage in the range of 1 kV to 250 kV between the electrodes. In addition, the distance between electrodes is the range of 1 mm-10 mm, for example.

  As described above, when the through holes are formed in the insulating substrate, the electrodes are arranged above and below the insulating substrate. Next, in a state where the insulating substrate is irradiated with laser light and the target position (through hole forming position) is heated, a high frequency voltage is applied to the electrode from the high frequency high voltage power source to generate a discharge at the same position. As a result, the insulating substrate is locally melted. Next, by applying a direct current high voltage between the electrodes, the melt is removed and a through hole is formed in the insulating substrate.

  Each time the through hole is formed, the electrode is moved relative to the insulating substrate. And the same operation is performed in a new object position, and a through-hole is continuously formed in an insulating substrate. The time from the formation of one through hole to the formation of the next through hole is, for example, in the range of 1 msec to 2 msec.

The diameter of the opening of the through hole is, for example, in the range of 10 μm to 70 μm. The formation density of the through holes is, for example, in a range of 1000 / cm ^{2 to} 2000 / cm ² . Moreover, the pitch P between through-holes is 100 micrometers, for example.

Here, in the present invention, step S120 is performed as follows.
(A) Of the n target positions where the through-hole is formed, when the target position at the center is one, the target position is referred to as the center position,
(B) Of the n target positions in which the through hole is formed, when there are two or more target positions at the center, the target positions are referred to as a central target position group,
The center position or the center object in a quadrilateral composed of two sides parallel to the horizontal X direction and two sides parallel to the vertical Y direction with the four target positions selected from the target positions as vertices When the smallest rectangle including the position group is drawn, the target positions located on the four sides and the four vertices of the rectangle are defined as the first target position group,
The first target position group is a quadrilateral composed of two side parallel to the horizontal X direction and two sides parallel to the vertical Y direction with the four target positions selected from the target positions as vertices. When the smallest rectangle included inside is drawn, the target positions located on the four sides and the four vertices of the square are set as the second target position group,
Similarly,
The (k-1) th object is a quadrangle formed by two object positions selected from the object positions as vertices and having two sides parallel to the horizontal X direction and two sides parallel to the vertical Y direction. When the smallest rectangle including the position group is drawn, and the target positions located on the four sides and the four vertices of the rectangle are the k-th target position group (where k is an integer of 2 or more),
(B1) First, a step of forming a through hole in all the target positions belonging to the central position or the central target position group;
(B2) Next to the step (b1), a step of forming through holes in all the target positions belonging to the first target position group;
...
(Bk) Next to the step (b (k-1)), a step of forming through holes in all the target positions belonging to the k-th target position group;
including.

  As described above, by forming the through holes in this order, it is possible to reduce the problem that the through hole formation position deviates from the desired position in the through hole formation process in the “through hole formation incomplete region”. It becomes possible to do. Also, the problem of collision between the insulating substrate and the electrode pair is reduced.

  As described above, according to the present invention, it is possible to provide a method in which the formation position of the through hole is not easily displaced when the insulating substrate for the interposer is manufactured using the laser induction type electric discharge machining technique. In addition, it is possible to provide a method in which the problem of collision between an electrode and an insulating substrate is reduced when an insulating substrate for an interposer is manufactured using a laser induction type electric discharge machining technique.

  The present invention can be used for manufacturing an interposer or the like.

DESCRIPTION OF SYMBOLS 100 Laser induction type electrical discharge machining apparatus 110 Laser light source 113 Laser light 130 High frequency high voltage power supply 140 DC high voltage power supply 150 Switching unit 160A, 160B Electrode 162A, 162B Conductor 180 Insulating substrate 183 Irradiation position 185 Through hole 185A-185F Through hole 185P, 185Q Through-hole 190 Stage 192 Hollow portion 210 Restraint member 430 Through-hole formation complete area 440 Through-hole formation incomplete area.

Claims (8)

A method of forming a plurality of through holes in an insulating substrate using laser induced discharge technology,
(I) preparing an insulating substrate;
(Ii) sequentially forming a total of n (where n is an integer of 9 or more) through holes on the surface of the insulating substrate at a constant pitch P in the horizontal X direction and the vertical Y direction;
Have
The step (ii)
(A) Of the n target positions where the through-hole is formed, when the target position at the center is one, the target position is referred to as the center position,
(B) Of the n target positions in which the through hole is formed, when there are two or more target positions at the center, the target positions are referred to as a central target position group,
The center position or the center object in a quadrilateral composed of two sides parallel to the horizontal X direction and two sides parallel to the vertical Y direction with the four target positions selected from the target positions as vertices When the smallest rectangle including the position group is drawn, the target positions located on the four sides and the four vertices of the rectangle are defined as the first target position group,
The first target position group is a quadrilateral composed of two side parallel to the horizontal X direction and two sides parallel to the vertical Y direction with the four target positions selected from the target positions as vertices. When the smallest rectangle included inside is drawn, the target positions located on the four sides and the four vertices of the square are set as the second target position group,
Similarly,
The (k-1) th object is a quadrangle formed by two object positions selected from the object positions as vertices and having two sides parallel to the horizontal X direction and two sides parallel to the vertical Y direction. When the smallest rectangle including the position group is drawn, and the target positions located on the four sides and the four vertices of the rectangle are the k-th target position group (where k is an integer of 2 or more),
(B1) First, a step of forming a through hole in all the target positions belonging to the central position or the central target position group;
(B2) Next to the step (b1), a step of forming through holes in all the target positions belonging to the first target position group;
...
(Bk) Next to the step (b (k-1)), a step of forming through holes in all the target positions belonging to the k-th target position group;
A method comprising the steps of:   The method according to claim 1, wherein the order in which through holes are formed at the n target positions is spiral.   3. The method according to claim 1, wherein a time period from the formation of the through hole at one target position to the formation of the through hole at the next target position is in a range of 1 msec to 2 msec.   The method according to claim 1, wherein the diameter of each through hole is in the range of 5 μm to 200 μm.   The method according to claim 1, wherein the insulating substrate has a thickness in a range of 0.3 mm to 1.0 mm.   The method according to claim 1, wherein the pitch P is in a range of 30 μm to 500 μm. The method according to claim 1, wherein a through-hole density in the surface of the insulating substrate is in a range of 1000 / cm ^{2 to} 2000 / cm ² . A method of manufacturing an insulating substrate for an interposer having a plurality of through holes using laser induced discharge technology,
(I) preparing an insulating substrate;
(Ii) sequentially forming a total of n (where n is an integer of 9 or more) through holes on the surface of the insulating substrate at a constant pitch P in the horizontal X direction and the vertical Y direction;
Have
The step (ii)
(A) Of the n target positions where the through-hole is formed, when the target position at the center is one, the target position is referred to as the center position,
(B) Of the n target positions in which the through hole is formed, when there are two or more target positions at the center, the target positions are referred to as a central target position group,
The center position or the center object in a quadrilateral composed of two sides parallel to the horizontal X direction and two sides parallel to the vertical Y direction with the four target positions selected from the target positions as vertices When the smallest rectangle including the position group is drawn, the target positions located on the four sides and the four vertices of the rectangle are defined as the first target position group,
The first target position group is a quadrilateral composed of two side parallel to the horizontal X direction and two sides parallel to the vertical Y direction with the four target positions selected from the target positions as vertices. When the smallest rectangle included inside is drawn, the target positions located on the four sides and the four vertices of the square are set as the second target position group,
Similarly,
The (k-1) th object is a quadrangle formed by two object positions selected from the object positions as vertices and having two sides parallel to the horizontal X direction and two sides parallel to the vertical Y direction. When the smallest rectangle including the position group is drawn, and the target positions located on the four sides and the four vertices of the rectangle are the k-th target position group (where k is an integer of 2 or more),
(B1) First, a step of forming a through hole in all the target positions belonging to the central position or the central target position group;
(B2) Next to the step (b1), a step of forming through holes in all the target positions belonging to the first target position group;
...
(Bk) Next to the step (b (k-1)), a step of forming through holes in all the target positions belonging to the k-th target position group;
A method comprising the steps of:

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