JP2013225687A - Through wiring board and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a through wiring board in which through wiring without void which becomes a defect, is disposed in a conductor filling the inside of a through hole, and a manufacturing method of the through wiring board with which generation of the void in filling the through hole or a non-through hole with the conductor can be suppressed.SOLUTION: A through hole 4 is disposed which connects one principal surface 2 and the other principal surface 3 constituting a plate-like board 1, and a through wiring board 10 comprises through wiring 6 which is configured by filling the through hole 4 with a conductor 5. The through wiring board 10 is characterized in that, when the through hole 4 is viewed on one longitudinal cross section of the board 1, the through hole 4 is formed in the shape of a trapezoid with inner side faces of the through hole 4 as sides 4p and 4q, the two sides 4p and 4q of the trapezoid are not parallel with each other, and the two sides 4p and 4q are inclined to the same side, respectively, with respect to two perpendiculars Tand Tdrawn to a straight line including a counter side from two apexes forming an upper bottom or a lower bottom of the trapezoid.

Description

  The present invention relates to a through wiring substrate having a through wiring penetrating the inside of the substrate and a method for manufacturing the same.

2. Description of the Related Art Conventionally, as a method for electrically connecting devices individually mounted on one main surface and the other main surface of a substrate, a method of providing a through wiring penetrating the inside of the substrate has been used.
As an example of the through wiring substrate, Patent Document 1 describes a through wiring substrate including a through wiring in which a through hole having a portion extending in a direction different from the thickness direction of the substrate is filled with a conductor.

  An example is shown in FIG. In this through wiring substrate 100, a through hole 104 is arranged so as to connect one main surface 102 and a side surface 103 constituting a substrate 101 made of quartz glass or the like, and copper (Cu), tungsten (W ), And a through wiring 106 filled with a conductor 105 such as gold tin (Au—Sn).

Conventionally, in order to form such a through wiring 106 inside the substrate 101, after forming a through hole 104 extending obliquely inside the substrate 101, a plating method, a sputtering method, a molten metal filling method, a CVD method, a supercritical film formation A method of filling the conductor 105 by a method or the like is used.
Of these methods, conductor filling by plating is often used for consistency with semiconductor processes.

As an example, FIG. 18 shows a conventional method for manufacturing the through wiring substrate 100 by electroplating. First, a through-hole 104 extending in an oblique direction with respect to one main surface 102 of the substrate 101 is formed in the substrate 101 (FIG. 18A). Next, a seed layer 115 for electroplating is formed on the inner wall surface and one main surface 102 (FIG. 18B). Subsequently, after appropriately patterning with a resist 113 on the seed layer 115 on one main surface 102 (FIG. 18C), the substrate 101 is formed in order to fill the conductors 105 into the through holes 104 by electroplating. By immersing in a plating solution, an appropriate current is passed between the seed layer 107 and an anode electrode (not shown) separately provided in the plating solution to deposit a conductor 105 in the through hole 104, thereby forming the through wiring 106. It forms (FIG.18 (d)). Thereafter, the penetrating wiring substrate 100 is obtained by an appropriate method, except for the seed layer 115 and the resist 113 on one main surface 102 (FIG. 17). In FIG. 17, the seed layer 115 is not omitted.
In the above description, the method of filling the through hole with the conductor using the electroplating method has been described, but the through hole can be filled with the conductor also by the electroless plating method.

JP 2006-303360 A

  However, in the conventional manufacturing method, a void (void) 109 that is not filled with the conductor 105 is formed in the through hole 104 during plating, and the opening 107 of the through hole 104 is formed while the void 109 remains. The problem of being blocked by the conductor 105 often occurs (FIG. 19). If the void 109 is generated, a foreign substance such as a plating solution remains in the void 109, which may adversely affect the through wiring 106, the through wiring board 100, and the mounted electronic device.

  The present invention has been made in view of the above circumstances, and includes a through-wiring board on which a through-wiring without a void is formed in a conductor filled in the through-hole, and a conductor in the through-hole or non-through-hole It is an object of the present invention to provide a method of manufacturing a through wiring substrate that can suppress the generation of voids during filling.

  When the present inventors diligently examined the problem in the conventional manufacturing method, the clue which solves a problem in the shape of the opening parts 107 and 108 of the through-hole 104 was obtained (refer FIG. 20). That is, the openings 107 and 108 have portions 110 and 111 with sharp shapes in their cross sections, respectively. Here, due to the nature of the plating, the plating grows preferentially at the sharp portions 110 and 111, and the openings 110 and 111 are blocked before the through hole 104 is filled with the conductor 105. As a result, it was discovered that the void 109 was generated, and the following solution was found.

  According to a first aspect of the present invention, there is provided a method for manufacturing a through wiring substrate, wherein a through hole connecting one main surface and the other main surface constituting a planographic substrate is provided, and the through hole is filled with a conductor. When the through-hole is viewed in one longitudinal section of the substrate, the through-hole has a trapezoidal shape with the inner side surface of the through-hole as a side, and the trapezoidal 2 Two side edges are non-parallel to each other, and two side edges of the trapezoid form two vertical lines drawn from two vertices forming the upper or lower base of the trapezoid to a straight line including the opposite side. A method of manufacturing a through wiring board that is inclined to the same side, wherein a region to be a through hole connecting both main surfaces of the substrate is modified by laser irradiation, and the one main surface is changed from the other main surface. Step (A) for forming a modified portion that gradually increases in thickness toward the surface and the modified portion are excluded. Then, the step (B) of forming a non-through hole having a first opening on the one main surface and an end serving as the second opening existing in the substrate; and A step (C) of forming a seed layer on the inner wall, a step (D) of filling a conductor inside the non-through hole via the seed layer, and grinding the other main surface to form the non-through hole And (E) forming the second opening on the other main surface.

  According to a second aspect of the present invention, there is provided a method of manufacturing a through wiring substrate, wherein a through hole connecting one main surface and the other main surface constituting a planographic substrate is disposed, and the through hole is filled with a conductor. When the through-hole is viewed in one longitudinal section of the substrate, the through-hole has a trapezoidal shape with the inner side surface of the through-hole as a side, and the trapezoidal 2 Two side edges are non-parallel to each other, and two side edges of the trapezoid form two vertical lines drawn from two vertices forming the upper or lower base of the trapezoid to a straight line including the opposite side. A method of manufacturing a through wiring board that is inclined to the same side, wherein a region to be a through hole connecting both main surfaces of the substrate is modified by laser irradiation, and the one main surface is changed from the other main surface. A step (G) of forming a modified portion that gradually increases in thickness toward the surface, and removing the modified portion. A step (H) of forming through holes having first and second openings in the one and other main surfaces, and a step (I) of attaching a conductor layer to the other main surface, And (J) filling the inside of the through hole with a conductor via the conductor layer.

  According to a third aspect of the present invention, there is provided a method of manufacturing a through wiring substrate, wherein a through hole connecting one main surface and the other main surface constituting a planographic substrate is provided, and the through hole is filled with a conductor. When the through-hole is viewed in one longitudinal section of the substrate, the through-hole has a trapezoidal shape with the inner side surface of the through-hole as a side, and the trapezoidal 2 Two side edges are non-parallel to each other, and two side edges of the trapezoid form two vertical lines drawn from two vertices forming the upper or lower base of the trapezoid to a straight line including the opposite side. A method of manufacturing a through wiring board inclined to the same side, the step (M) of attaching a base material having a conductor layer in contact with the other surface of the board in contact with the conductor layer; A region that becomes a through hole connecting the main surfaces is modified by laser irradiation, and the one of the other main surfaces is The step (N) of forming a modified portion that gradually increases toward the main surface, the modified portion is removed, the first main surface has a first opening, and the other A step (O) of forming a through hole having a second opening at a boundary surface where the main surface and the conductor layer contact each other, and a step (P) of filling a conductor into the through hole through the conductor layer It is characterized by including these.

According to the through wiring board of the present invention, the conductor filled in the through hole is provided with a through wiring without a void that becomes a defect. Therefore, the conductor is peeled off in the through hole, It is possible to provide a through wiring board with improved reliability at the time of device mounting without fear of leakage of trapped foreign substances.
In addition, according to the method for manufacturing a through wiring board of the present invention, it is possible to suppress the generation of voids when a through hole or a non-through hole is filled with a conductor. A wiring board can be manufactured.

It is sectional drawing which shows an example of the penetration wiring board concerning this invention. It is sectional drawing which shows an example of the penetration wiring board concerning this invention. It is a perspective view which shows an example of the penetration wiring board concerning the present invention. It is the top view and sectional drawing which show the manufacturing method in an example of the penetration wiring board concerning the present invention. It is the top view and sectional drawing which show the 1st aspect of the manufacturing method of the penetration wiring board concerning the present invention. It is the top view and sectional drawing which show the 1st aspect of the manufacturing method of the penetration wiring board concerning the present invention. It is the top view and sectional drawing which show the 1st aspect of the manufacturing method of the penetration wiring board concerning the present invention. It is the top view and sectional drawing which show the 1st aspect of the manufacturing method of the penetration wiring board concerning the present invention. It is the top view and sectional drawing which show the 2nd aspect of the manufacturing method of the penetration wiring board concerning the present invention. It is the top view and sectional drawing which show the 2nd aspect of the manufacturing method of the penetration wiring board concerning the present invention. It is the top view and sectional drawing which show the 2nd aspect of the manufacturing method of the penetration wiring board concerning the present invention. It is the top view and sectional drawing which show the 2nd aspect of the manufacturing method of the penetration wiring board concerning the present invention. It is the top view and sectional drawing which show the 3rd aspect of the manufacturing method of the penetration wiring board concerning the present invention. It is the top view and sectional drawing which show the 3rd aspect of the manufacturing method of the penetration wiring board concerning the present invention. It is the top view and sectional drawing which show the 3rd aspect of the manufacturing method of the penetration wiring board concerning the present invention. It is the top view and sectional drawing which show the 3rd aspect of the manufacturing method of the penetration wiring board concerning the present invention. It is sectional drawing which shows an example of the conventional penetration wiring board. It is sectional drawing which shows the manufacturing method of the conventional penetration wiring board. It is sectional drawing which shows the state in which the void produced in the through-hole in the manufacturing method of the conventional penetration wiring board. It is sectional drawing which shows the middle stage in the manufacturing method of the conventional penetration wiring board.

The present invention will be described below based on preferred embodiments with reference to the drawings.
FIG. 1 is a longitudinal sectional view of a through wiring board 10 which is an example of a through wiring board according to the present invention cut in the thickness direction. The through wiring substrate 10 includes a through hole 4 that connects one main surface 2 and the other main surface 3 constituting the planographic substrate 1, and the through hole 4 is filled with a conductor 5. When the through-hole 4 is viewed in one longitudinal section of the substrate 1, the through-hole 4 has a trapezoidal shape with the inner side surface of the through-hole 4 as a side, two side 4p and 4q of the trapezoid is non-parallel to each other, and the two vertices forming the trapezoidal upper bottom or the lower bottom, two vertical lines T ₁ and T ₂ which are drawn to the straight line including the opposite side On the other hand, the two sides 4p and 4q of the trapezoid are inclined to the same side.

  The upper base of the trapezoid is formed by the first opening 7 of the through hole 4 in one main surface 2, and the lower base of the trapezoid is the second opening 8 of the through hole 4 in the other main surface 3. The two sides of the trapezoid are formed by the inner side surface (side 4p and side 4q) of the through hole 4. In FIG. 1, the length of the upper base> the length of the lower base.

In FIG. 1, vertical lines T ₁ and T ₂ are respectively drawn from two vertices (both ends of the lower base) forming the lower base of the trapezoid to a straight line (one main surface 2 of the substrate 1) including the upper base that is the opposite side. ing. As shown by the arrows in FIG. 1, the sides 4p of the trapezoid are inclined to the left with respect to the perpendicular T _1, the trapezoid sides 4p is inclined to the left with respect to the perpendicular T _2. That is, the sides 4p and 4q, to the perpendicular line _{T 1} and _{T 2,} respectively, are inclined in the same left side.

  FIG. 2 is a longitudinal sectional view taken in the thickness direction of the through wiring board 10 which is an example of the through wiring board according to the present invention, and shows the same cross section as FIG. However, FIG. 2 shows the directions of the side edges 4p and 4q with respect to the normal T passing through both main surfaces of the substrate 1.

  That is, the through wiring substrate 10 is provided with a through hole 4 connecting one main surface 2 and the other main surface 3 constituting the planographic substrate 1, and the through hole 4 is filled with a conductor 5. When the through hole 4 is seen in one longitudinal section of the substrate 1, the through hole 4 has side surfaces 4 p and 4 q on the inner side surface of the through hole 4. A trapezoidal shape, the two sides 4p and 4q of the trapezoid are non-parallel to each other, and two directions from one main surface 2 to the other main surface 3 along each side of the trapezoid ( (Directions represented by arrows α and β) are directed to the same side with respect to the normal T passing through both main surfaces of the substrate 1.

In FIG. 2, the two directions from one main surface 2 to the other main surface 3 along each side of the trapezoid are directed to the same side with respect to the perpendicular T. The directions indicated by β are both directed to the right side of the page with respect to the perpendicular T.
On the other hand, if the direction indicated by the arrow α is directed to the right side of the paper with respect to the perpendicular T and the direction indicated by the arrow beta is directed to the left side of the paper with respect to the vertical T, the two directions Is directed to a different side with respect to the perpendicular T.

  In other words, the through wiring board 10 has the through hole 4 arranged so as to connect one main surface 2 and the other main surface 3 constituting the single substrate 1, and the through wiring board 10 has a through hole. A through-wiring board 10 having a through-wiring 6 in which a hole 4 is filled with a conductor 5, the through-hole 4 extending obliquely with respect to one main surface 2 and the other main surface 3, and The first opening 7 narrows in a substantially tapered shape from the second opening 8 toward the second opening 8.

  The cross section of the through wiring substrate 10 in FIG. 2 is a cross section along the center of the first opening 7 and the center of the second opening 8 in the through hole 4. The through hole 4 is inclined and extended with respect to the one main surface 2 and the other main surface 3. That is, as shown in the perspective view of FIG. 3, the central axis J of the through hole 4 extends in a direction different from the thickness direction of the substrate 1. The central axis J passes through the center of the region of the through hole 4 included in an arbitrary plane parallel to the one main surface 2 or the other main surface 3. 1 and 2 are cross-sectional views taken along line XX of FIG.

  In the cross-sectional view of FIG. 2, if the angles formed by the opposite side 4p and side 4q of the through-hole 4 with one main surface 2 are expressed as an angle θ and an angle φ, respectively, the sum of the angle θ and the angle φ is 180 degrees (° ) Super. Here, the angle θ is an acute angle, and the angle φ is an obtuse angle. In this case, the side 4p and the side 4q are directed to the same side with respect to the perpendicular T passing through one main surface 2. Further, the shape of the through hole 4 becomes narrower in a substantially tapered shape from the first opening 7 toward the second opening 8. Note that the sides 4p and 4q are the two sides of the trapezoid.

  The two sides of the trapezoid are non-parallel to each other and are directed to the same side with respect to the normal T passing through one main surface 2 of the substrate 1, and the through-hole 4 is formed on one main surface 2 and the other of the substrate 1. Since the main surface 3 is inclined and extended, the position of the opening 7 on one main surface 2 and the position of the opening 8 on the other main surface 3 can be designed with a high degree of freedom. The through wiring 6 can be freely arranged in accordance with the arrangement of the electrode portions of the respective devices mounted on both surfaces of the through wiring substrate 10.

  Further, since the through hole 4 has a substantially tapered shape that becomes narrower from the first opening 7 toward the second opening 8, the conductor 5 is filled in the through hole 4 when the through wiring substrate 10 is manufactured. Thus, when the through wiring 6 is formed, formation of voids (voids) can be suppressed. For this reason, the through-wiring board 10 provided with the through-wiring 6 having no defective voids can have high reliability in use.

As a material of the board | substrate 1 in the through wiring board 10 of this invention shown above, insulators, such as glass, sapphire, a plastics, ceramics, and semiconductors, such as silicon (Si), are mentioned, for example. Among these materials, insulating quartz glass is preferable. When the substrate material is quartz glass, there is an advantage that there is no need to form an insulating layer on the inner wall of the through hole, which will be described later, and there is no hindrance to high-speed transmission due to the presence of stray capacitance components.
The thickness of the substrate 1 (distance from one main surface 2 to the other main surface 3) can be appropriately set within a range of about 150 μm to 1 mm.
Examples of the conductor 5 that fills the through hole 4 disposed in the through wiring substrate 10 include gold tin (Au—Sn) and copper (Cu).

  The pattern of the through wiring 6 provided in the through wiring board 10 of the present invention is not limited to the above examples, and can be appropriately designed.

<First Aspect of Manufacturing Method of Penetration Wiring Board>
Next, FIGS. 4 to 8 show a first embodiment of a method for manufacturing the through wiring board 10 which is an example of the through wiring board of the present invention.
4 to 8 are a plan view and a cross-sectional view of the substrate 1 on which the through wiring substrate 10 is manufactured. In the figure, (A) is a plan view of the substrate 1, and (B) is a cross-sectional view of the substrate 1 taken along line XX of the plan view.

The 1st aspect of the manufacturing method of the penetration wiring board 10 concerning the present invention has at least 5 processes of the following processes AE.
Here, as described with reference to FIG. 1, the through wiring substrate 10 is provided with a through hole 4 that connects one main surface 2 and the other main surface 3 constituting the planographic substrate 1, and A through-wiring board 10 having a through-wiring 6 formed by filling the through-hole 4 with a conductor 5 when the through-hole 4 is viewed in one longitudinal section of the substrate 1 is the through-hole 4. The trapezoidal two sides 4p and 4q are non-parallel to each other and include opposite sides from two vertices forming the upper or lower base of the trapezoid. against two perpendicular T ₁ and T ₂ which is pulled linearly, two side 4p and 4q of the trapezoid are inclined respectively on the same side.

  Further, as described with reference to FIG. 2, the through wiring substrate 10 is provided with a through hole 4 connecting one main surface 2 and the other main surface 3 constituting the planographic substrate 1, and the through hole 4 A through-wiring board 10 having a through-wiring 6 in which a hole 5 is filled with a conductor 5, and when the through-hole 4 is viewed in one longitudinal section of the board 1, It has a trapezoidal shape with the inner side faces 4p and 4q, and the two side edges 4p and 4q of the trapezoid are not parallel to each other and extend from one main surface 2 to the other along each side edge of the trapezoid. The two directions (directions represented by arrows α and β) toward the main surface 3 are directed to the same side with respect to the normal T passing through both main surfaces of the substrate 1.

  That is, the through wiring board 10 has a through hole 4 so as to connect one main surface 2 and the other main surface 3 constituting a single substrate 1, and the through hole 4 is filled with a conductor 5. The through-hole wiring board 10 includes the through-hole wiring 6, and the through-hole 4 extends obliquely with respect to the one main surface 2 and the other main surface 3, and the second opening is provided through the first opening 7. It becomes thin in the shape of a taper toward the opening 8.

<Process A>
In step A, the region to be the through hole 4 connecting both main surfaces of the substrate 1 is modified by laser irradiation.
As an example of the method, as shown in FIG. 4, there is a method of irradiating the substrate 1 with a laser beam L to form a modified portion 16 in which the material of the substrate 1 is modified in the substrate 1. The reforming unit 16 is provided in a region to be the through wiring 6.

Examples of the material of the substrate 1 include insulators such as glass, sapphire, plastic, and ceramics, and semiconductors such as silicon (Si). Among these materials, insulating quartz glass is preferable. When the substrate material is quartz glass, there is an advantage that there is no need to form an insulating layer on the inner wall of a through hole, which will be described later, and there is no hindrance to high-speed transmission due to the presence of stray capacitance components.
The thickness of the substrate 1 (distance from one main surface 2 to the other main surface 3) can be appropriately set within a range of about 150 μm to 1 mm.

  The laser beam L is irradiated from, for example, one main surface 2 side of the substrate 1 and forms a focal point S at a desired position in the substrate 1. At the position where the focal point S is connected, the material of the substrate 1 is modified. Accordingly, the position of the focal point S is sequentially shifted and moved (scanned) while irradiating the laser light L, and the modified portion 16 is formed by connecting the focal point S to the entire region serving as the through hole 4. be able to.

  Examples of the light source of the laser light L include a femtosecond laser. By irradiating the laser beam L, for example, the modified portion 16 having a diameter of several μm to several tens of μm can be obtained. Further, by controlling the position at which the focal point S of the laser beam L is connected inside the substrate 1, the modified portion 16 having a desired shape can be formed.

  As the laser irradiation method, for example, from the second end 18 existing in the substrate 1 serving as the second opening 8 of the through hole 4 toward the first end 17 serving as the first opening 7. When modifying by laser irradiation, the laser beam is appropriately scanned to gradually increase in thickness from the second end portion 18 toward the first end portion 17 (that is, from the first end portion 17 to the first end portion 17). And a method of forming the reforming portion 16 having a substantially tapered shape that narrows toward the second end portion 18.

  In the present embodiment, the angle θ and the angle φ are adjusted to be 70 degrees and 120 degrees, respectively, so that the radii of the first end portion 17 and the second end portion 18 are 15 μm and 5 μm, respectively. A mass 16 was formed.

  The arrow shown in the cross-sectional view (B) of FIG. 4 represents the direction in which the focal point S of the laser light L is scanned. That is, the arrow indicates that the focal point S is scanned from the second end 18 to the first end 17. At this time, it is preferable in terms of manufacturing efficiency to perform one-stroke scanning in the direction of the arrow.

  As described above, when the modified portion 16 is formed, the laser beam L may be irradiated only from one or the other main surface of the substrate 1 or both of the substrates 1 may be irradiated. Laser light L may be irradiated from the main surface.

<Process B>
In step B, the modified portion 16 formed in step A is removed, the first end 7 is formed on one main surface 2 of the substrate 1, and the second end portion that becomes the second opening 8. A non-through hole 14 is formed in the substrate 1.
As an example of the method, as shown in FIG. 5, the substrate 1 on which the modified portion 16 is formed is immersed in an etching solution (chemical solution) 19, and the modified portion 16 is etched (wet etching). The method of removing is mentioned. As a result, a non-through hole 14 (blind via) is formed in a portion where the reforming portion 16 exists. In this embodiment, a quartz glass plate having a thickness of 500 μm is used as the material of the substrate 1, and a solution mainly containing hydrofluoric acid (HF) is used as the etching solution 19. This etching utilizes the phenomenon that the modified portion 16 is etched much faster than the unmodified portion of the substrate 1, and as a result, the non-through hole 14 corresponding to the shape of the modified portion 16. Can be formed.

  The etching solution 19 is not particularly limited, and for example, a solution containing hydrofluoric acid (HF) as a main component, or a hydrofluoric acid-based mixed acid obtained by adding an appropriate amount of nitric acid or the like to hydrofluoric acid can be used. Further, other chemicals can be used depending on the material of the substrate 1.

<Process C>
In the process C, the seed layer 15 is formed on the inner wall of the non-through hole 14 formed in the process B and the one main surface 2.
As an example of the method, as shown in FIG. 6, a titanium (Ti) thin film having a thickness of 50 nm is first formed by sputtering, and then a copper (Cu) thin film having a thickness of 150 nm is formed by sputtering. There is a method of forming the seed layer 15 made of a Cu / Ti thin film by two-stage film formation.
The material of the seed layer 15 is not limited to titanium and copper, and gold (Au) or gold tin (Au—Sn) can be used. What is necessary is just to select suitably according to the material of the conductor 5 with which the process D of a back | latter stage is filled.

<Process D>
In Step D, the conductor 5 is filled into the non-through hole 16 through the seed layer 15 formed in Step C.
As an example of the method, as shown in FIG. 7, the surface of the seed layer 15 other than the portion to be plated is covered with a resist 13 and then immersed in a plating solution (not shown). Here, the resist 13 is patterned except for the inner wall of the non-through hole 14 and the periphery of the first opening 7. As a component of the plating solution, a copper sulfate plating solution suitable for filling the non-through holes 14 is preferably used.

  The seed layer not covered with the resist 13 is obtained by immersing the substrate 1 having a resist pattern in the plating solution and passing an appropriate current between the seed layer 15 and a separately provided anode electrode (not shown). The conductor 5, which is a plated metal, is deposited via 15, whereby the conductor 5 is filled into the non-through hole 14. The seed layer 15 and the resist layer 13 on one main surface are appropriately removed after the conductor 5 is filled.

  Here, as described above, the shape of the non-through hole 14 is processed so as to become thinner in a substantially tapered shape from the first opening 7 toward the second end 18 (second opening 8). Therefore, it is possible to prevent the conductor 5 from closing the first opening 7 and generating a region (void) in which the conductor 5 is not filled in the non-through hole 14. That is, the non-through hole 14 in which the seed layer 15 is formed has a shape that gradually increases from the second end portion 18 toward the first opening 7, and therefore, the conductor 5 is interposed via the seed layer 15 by plating. The second end 18 on the narrower side is filled faster than the first opening on the thicker side. For this reason, it can suppress that the void which becomes a defect generate | occur | produces in the inside of the filled conductor 5, and can obtain the non-penetrating wiring 12 which filled the conductor 5 in the non-through-hole 14 closely.

<Process E>
In step E, the other main surface 3 of the substrate 1 having the non-through wiring 12 formed in step D is ground (polished), and the non-through hole 14 and the non-through wiring 12 are respectively connected to the through hole 4 and the through wiring 6. None, the second opening 8 is formed in the other main surface 3.
More specifically, the other main surface 3 is ground, and the substrate 1 is thinned to a desired thickness so that the second end 18 existing in the substrate 1 is exposed to the other main surface 3. Moreover, you may grind one main surface 2 if desired. By grinding one main surface 2, the surface of the conductor 5 in the first opening 7 can be smoothed.
As the grinding method, a physical / chemical method such as mechanochemical polishing (MCP) may be applied.
Through the above steps A to E, the through wiring substrate 10 shown in FIG. 8 is obtained.

<Second Aspect of Manufacturing Method of Penetration Wiring Board>
Next, FIGS. 9 to 12 show a second embodiment of a method for manufacturing the through wiring board 10 which is an example of the through wiring board of the present invention.
Here, FIGS. 9 to 12 are a plan view and a cross-sectional view of the substrate 1 for manufacturing the through wiring substrate 10. In the figure, (A) is a plan view of the substrate 1, and (B) is a cross-sectional view of the substrate 1 taken along line YY in the plan view.

The 2nd aspect of the manufacturing method of the penetration wiring board 10 concerning the present invention has at least 4 processes of the following processes GJ.
Here, as described with reference to FIG. 1, the through wiring substrate 10 is provided with a through hole 4 that connects one main surface 2 and the other main surface 3 constituting the planographic substrate 1, and A through-wiring board 10 having a through-wiring 6 formed by filling the through-hole 4 with a conductor 5 when the through-hole 4 is viewed in one longitudinal section of the substrate 1 is the through-hole 4. The trapezoidal two sides 4p and 4q are non-parallel to each other and include opposite sides from two vertices forming the upper or lower base of the trapezoid. against two perpendicular T ₁ and T ₂ which is pulled linearly, two side 4p and 4q of the trapezoid are inclined respectively on the same side.

  Further, as described with reference to FIG. 2, the through wiring substrate 10 is provided with a through hole 4 connecting one main surface 2 and the other main surface 3 constituting the planographic substrate 1, and the through hole 4 A through-wiring board 10 having a through-wiring 6 in which a hole 5 is filled with a conductor 5, and when the through-hole 4 is viewed in one longitudinal section of the board 1, It has a trapezoidal shape with the inner side faces 4p and 4q, and the two side edges 4p and 4q of the trapezoid are not parallel to each other and extend from one main surface 2 to the other along each side edge of the trapezoid. The two directions (directions represented by arrows α and β) toward the main surface 3 are directed to the same side with respect to the normal T passing through both main surfaces of the substrate 1.

  That is, the through wiring board 10 has a through hole 4 so as to connect one main surface 2 and the other main surface 3 constituting a single substrate 1, and the through hole 4 is filled with a conductor 5. The through-hole wiring board 10 includes the through-hole wiring 6, and the through-hole 4 extends obliquely with respect to the one main surface 2 and the other main surface 3, and the second opening is provided through the first opening 7. It becomes thin in the shape of a taper toward the opening 8.

<Process G>
In the process G, the region to be the through hole 4 connecting both main surfaces of the substrate 1 is modified by laser irradiation.
As an example of the method, as shown in FIG. 9, there is a method of irradiating the substrate 1 with a laser beam L to form a modified portion 16 formed by modifying the material of the substrate 1 in the substrate 1. The reforming unit 16 is provided in a region to be the through wiring 6.

  The description of the material of the substrate 1, the modification of the substrate 1 at the focal point S of the laser light L, and the description of the light source of the laser light L are the same as the description in the first aspect of the method for manufacturing the through wiring substrate.

  As a method of irradiating the laser beam L, for example, laser irradiation is performed from the second end 18 serving as the second opening 8 of the through hole 4 toward the first end 17 serving as the first opening 7. When the modification is performed, the laser beam is appropriately scanned to gradually increase in thickness from the second end portion 18 toward the first end portion 17 (that is, from the first end portion 17 to the second end portion). And a method of forming the reforming portion 16 having a substantially tapered shape that narrows toward the portion 18.

  In the present embodiment, the angle θ and the angle φ are adjusted to be 70 degrees and 120 degrees, respectively, so that the radii of the first end portion 17 and the second end portion 18 are 15 μm and 5 μm, respectively. A mass 16 was formed.

  The arrows shown in the cross-sectional view (B) of FIG. 9 indicate the direction in which the focal point S of the laser light L is scanned. That is, the arrow indicates that the focal point S is scanned from the second end 18 to the first end 17. At this time, it is preferable in terms of manufacturing efficiency to perform one-stroke scanning in the direction of the arrow.

  As described above, when the modified portion 16 is formed, the laser beam L may be irradiated only from one or the other main surface of the substrate 1 or both of the substrates 1 may be irradiated. Laser light L may be irradiated from the main surface.

<Process H>
In Step H, the modified portion 16 formed in Step G is removed, and the first opening 7 is provided on one main surface 2 of the substrate 1, and the second opening 8 is provided on the other main surface 3. The through-hole 4 is formed.
As an example of the method, as shown in FIG. 10, the substrate 1 on which the modified portion 16 is formed is immersed in an etching solution (chemical solution) 19 and the modified portion 16 is etched (wet etching). The method of removing is mentioned. As a result, the through hole 4 (via) is formed in the portion where the reforming portion 16 exists. In this embodiment, a quartz glass plate having a thickness of 500 μm is used as the material of the substrate 1, and a solution mainly containing hydrofluoric acid (HF) is used as the etching solution 19. This etching utilizes the phenomenon that the modified portion 16 is etched much faster than the unmodified portion of the substrate 1, and as a result, the through hole 4 corresponding to the shape of the modified portion 16 is formed. Can be formed.
In addition, after forming the modified portion in a straight line, a solution having a small etching solution selection ratio (ratio of the etching rate between the modified layer and the non-modified layer) is appropriately selected, and etching is always performed from one side of the substrate. A tapered hole can also be formed by making it advance.

  The etching solution 19 is not particularly limited, and for example, a solution containing hydrofluoric acid (HF) as a main component, or a hydrofluoric acid-based mixed acid obtained by adding an appropriate amount of nitric acid or the like to hydrofluoric acid can be used. Further, other chemicals can be used depending on the material of the substrate 1.

<Process I>
In step I, the conductor layer 21 is affixed to the other main surface 3.
As an example of the method, as shown in FIG. 11, there is a method in which a conductor layer 21 made of a copper plate having a thickness of 1 mm is fixed to the other main surface 3 with a jig (not shown).
The material of the conductor layer 21 is not limited to copper, and a material made of a conductive material such as titanium, gold, gold-tin, or the like can be used, and the thickness thereof is appropriately set.

<Process J>
In step J, the conductor 5 is filled into the through hole 4 through the conductor layer 21 fixed in step I.
As an example of the method, there is a method in which the substrate 1 having the conductor layer 21 attached to the other main surface 3 is immersed in a plating solution (not shown). As a component of the plating solution, a copper sulfate plating solution suitable for filling the through holes 4 is preferably used.

  The conductive layer 21 is in contact with the second opening 8 of the through hole 4 by immersing the substrate 1 and flowing an appropriate current between the conductive layer 21 and a separately provided anode electrode (not shown). The conductor 5 which is a plating metal deposits through the portion, whereby the conductor 5 is filled into the through hole 4 (see FIG. 12).

  Here, since the shape of the through hole 4 is processed so as to become thinner in a substantially tapered shape from the first opening 7 toward the second opening 8 as described above, the conductor 5 is formed in the first hole 7. It is possible to prevent the opening 7 from being blocked and generating a region (void) in which the conductor 5 is not filled in the through hole 4. That is, since the through-hole 4 has a shape that gradually increases from the second opening 8 toward the first opening 7, the conductor 5 is deposited through the conductive layer 21 by plating, and the thin-side first When the conductor 5 is filled from the second opening 8 toward the thicker first opening 7, the plating solution in the through hole 4 is smoothly replaced, and the fresh plating solution is uniformly filled in the through hole. Therefore, stable plating growth without precipitation abnormality is performed. For this reason, it is possible to obtain the through wiring 6 in which the conductor 5 is densely filled in the through hole 4 by suppressing the generation of a void as a defect in the filled conductor 5.

The conductor layer 15 is removed by an appropriate method from the other main surface 3 of the through wiring substrate 10 on which the through wiring 6 is formed. Further, the surfaces of the conductor 5 exposed to the first opening 7 and the second opening 8 may be smoothed by polishing both main surfaces of the through wiring substrate 10.
Through the above steps G to J, the through wiring substrate 10 shown in FIG. 8 is obtained.

In the manufacturing method of the second aspect described here, steps such as resist patterning and grinding of the second main surface 3 are not essential, so the number of processes is reduced as compared with the manufacturing method of the first aspect described above. Manufacturing efficiency is good.
Further, since the conductor 5 is deposited through the conductive layer 21 in contact with the second opening 8, the conductor 5 tends to fill the through hole 4 from the second opening 8 toward the first opening 7. Yes, the formation of voids can be further suppressed.

<Third Aspect of Manufacturing Method of Penetration Wiring Board>
Next, FIGS. 13 to 16 show a third embodiment of a method for manufacturing the through wiring board 10 which is an example of the through wiring board of the present invention.
Here, FIGS. 13 to 16 are a plan view and a cross-sectional view of the substrate 1 for manufacturing the through wiring substrate 10. In the figure, (A) is a plan view of the substrate 1, and (B) is a cross-sectional view of the substrate 1 taken along the line ZZ in the plan view.

The 3rd aspect of the manufacturing method of the penetration wiring board 10 concerning the present invention has at least 4 processes of the following processes MP.
Here, as described with reference to FIG. 1, the through wiring substrate 10 is provided with a through hole 4 that connects one main surface 2 and the other main surface 3 constituting the planographic substrate 1, and A through-wiring board 10 having a through-wiring 6 formed by filling the through-hole 4 with a conductor 5 when the through-hole 4 is viewed in one longitudinal section of the substrate 1 is the through-hole 4. The trapezoidal two sides 4p and 4q are non-parallel to each other and include opposite sides from two vertices forming the upper or lower base of the trapezoid. against two perpendicular T ₁ and T ₂ which is pulled linearly, two side 4p and 4q of the trapezoid are inclined respectively on the same side.

  Further, as described with reference to FIG. 2, the through wiring substrate 10 is provided with a through hole 4 connecting one main surface 2 and the other main surface 3 constituting the planographic substrate 1, and the through hole 4 A through-wiring board 10 having a through-wiring 6 in which a hole 5 is filled with a conductor 5, and when the through-hole 4 is viewed in one longitudinal section of the board 1, It has a trapezoidal shape with the inner side faces 4p and 4q, and the two side edges 4p and 4q of the trapezoid are not parallel to each other and extend from one main surface 2 to the other along each side edge of the trapezoid. The two directions (directions represented by arrows α and β) toward the main surface 3 are directed to the same side with respect to the normal T passing through both main surfaces of the substrate 1.

  That is, the through wiring board 10 has a through hole 4 so as to connect one main surface 2 and the other main surface 3 constituting a single substrate 1, and the through hole 4 is filled with a conductor 5. The through-hole wiring board 10 includes the through-hole wiring 6, and the through-hole 4 extends obliquely with respect to the one main surface 2 and the other main surface 3, and the second opening is provided through the first opening 7. It becomes thin in the shape of a taper toward the opening 8.

<Process M>
In step M, a base material 23 having a conductor layer 22 is attached to the other surface 3 of the substrate 1 in contact with the conductor layer 22.
As an example of the method, as shown in FIG. 13, a substrate 23 made of a resin having a conductor layer 22 made of a copper thin film having a thickness of 50 μm provided on one side is used with a jig (not shown). A method of fixing the conductor layer 22 so as to be in contact with the other surface 3 may be mentioned.
As a method of forming a copper thin film on one surface of the base material 23, for example, a sputtering method can be mentioned.

The material of the conductor layer 22 is not limited to copper, and a material made of a conductive material such as titanium, gold, gold-tin or the like can be used, and the thickness thereof is appropriately set.
The material of the base material 23 is not limited to resin, and may be a semiconductor substrate or a metal plate made of Si or the like. The thickness is appropriately set.

<Process N>
In step N, the region to be the through hole 4 connecting both main surfaces of the substrate 1 is modified by laser irradiation.
As an example of the method, as shown in FIG. 14, there is a method of irradiating the substrate 1 with a laser beam L to form a modified portion 16 in which the material of the substrate 1 is modified in the substrate 1. The reforming unit 16 is provided in a region to be the through wiring 6.

  The description of the material of the substrate 1, the modification of the substrate 1 at the focal point S of the laser light L, and the description of the light source of the laser light L are the same as the description in the first aspect of the method for manufacturing the through wiring substrate.

  As a method of irradiating the laser beam L, for example, laser irradiation is performed from the second end 18 serving as the second opening 8 of the through hole 4 toward the first end 17 serving as the first opening 7. When the modification is performed, the laser beam is appropriately scanned to gradually increase in thickness from the second end portion 18 toward the first end portion 17 (that is, from the first end portion 17 to the second end portion). And a method of forming the reforming portion 16 having a substantially tapered shape that narrows toward the portion 18.

  In the present embodiment, the angle θ and the angle φ are adjusted to be 70 degrees and 120 degrees, respectively, so that the radii of the first end portion 17 and the second end portion 18 are 15 μm and 5 μm, respectively. A mass 16 was formed.

An arrow shown in the cross-sectional view (B) of FIG. 14 represents a direction in which the focal point S of the laser light L is scanned.
That is, the arrow indicates that the focal point S is scanned from the second end 18 to the first end 17. At this time, it is preferable in terms of manufacturing efficiency to perform one-stroke scanning in the direction of the arrow.

  As described above, when the modified portion 16 is formed, the laser beam L may be irradiated only from one or the other main surface of the substrate 1 or both of the substrates 1 may be irradiated. Laser light L may be irradiated from the main surface.

<Process O>
In step O, the modified portion 16 formed in step P is removed, the first opening 7 is provided on one main surface 2, and the boundary surface where the other main surface 3 and the conductor layer 22 are in contact with each other is described above. A through hole 4 having a second opening 8 is formed.
As an example of the method, as shown in FIG. 15, the substrate 1 on which the modified portion 16 is formed is immersed in an etching solution (chemical solution) 19, and the modified portion 16 is etched (wet etching). The method of removing is mentioned. As a result, the through hole 4 (via) is formed in the portion where the reforming portion 16 exists. In this embodiment, a quartz glass plate having a thickness of 500 μm is used as the material of the substrate 1, and a solution mainly containing hydrofluoric acid (HF) is used as the etching solution 19. This etching utilizes the phenomenon that the modified portion 16 is etched much faster than the unmodified portion of the substrate 1, and as a result, the through hole 4 corresponding to the shape of the modified portion 16 is formed. Can be formed.
In addition, after forming the modified portion in a straight line, a solution having a small etching solution selection ratio (ratio of the etching rate between the modified layer and the non-modified layer) is appropriately selected, and etching is always performed from one side of the substrate. A tapered hole can also be formed by making it advance.

  The etching solution 19 is not particularly limited, and for example, a solution containing hydrofluoric acid (HF) as a main component, or a hydrofluoric acid-based mixed acid obtained by adding an appropriate amount of nitric acid or the like to hydrofluoric acid can be used. Further, other chemicals can be used depending on the material of the substrate 1.

<Process P>
In the process P, the conductor 5 is filled into the through hole 4 through the conductive layer 22 provided on one side of the base material 23 fixed to the other main surface 3 of the substrate 1 in the process M.
As an example of the method, there is a method in which the substrate 1 having the conductor layer 22 attached to the other main surface 3 is immersed in a plating solution (not shown). As a component of the plating solution, a copper sulfate plating solution suitable for filling the through holes 4 is preferably used.

  The conductive layer 22 is in contact with the second opening 8 of the through hole 4 by immersing the substrate 1 and flowing an appropriate current between the conductive layer 22 and a separately provided anode electrode (not shown). The conductor 5 which is a plating metal deposits through the portion, whereby the conductor 5 is filled into the through hole 4 (see FIG. 16).

  Here, since the shape of the through hole 4 is processed so as to become thinner in a substantially tapered shape from the first opening 7 toward the second opening 8 as described above, the conductor 5 is formed in the first hole 7. It is possible to prevent the opening 7 from being blocked and generating a region (void) in which the conductor 5 is not filled in the through hole 4. That is, since the through-hole 4 has a shape that gradually increases from the second opening 8 toward the first opening 7, the conductor 5 is deposited through the conductive layer 22 by plating, and the thin side first When the conductor 5 is filled from the second opening 8 toward the thicker first opening 7, the plating solution in the through hole 4 is smoothly replaced, and the fresh plating solution is uniformly filled in the through hole. Therefore, stable plating growth without precipitation abnormality is performed. For this reason, it is possible to obtain the through wiring 6 in which the conductor 5 is densely filled in the through hole 4 by suppressing the generation of a void as a defect in the filled conductor 5.

The conductor layer 22 and the base material 23 are removed by an appropriate method from the other main surface 3 of the through wiring substrate 10 on which the through wiring 6 is formed. Further, the surfaces of the conductor 5 exposed to the first opening 7 and the second opening 8 may be smoothed by polishing both main surfaces of the through wiring substrate 10.
Through the above steps MP, the through wiring substrate 10 shown in FIG. 8 is obtained.

In the manufacturing method of the third aspect described here, steps such as resist patterning and grinding of the second main surface 3 are not essential, so the number of processes is reduced compared to the manufacturing method of the first aspect described above. Manufacturing efficiency is good.
Further, since the conductor 5 is deposited via the conductive layer 22 in contact with the second opening 8, the conductor 5 tends to fill the through hole 4 from the second opening 8 toward the first opening 7. Yes, the formation of voids can be further suppressed.

  By using the through wiring board of the present invention, high density of various devices such as three-dimensional mounting for mounting devices on both main surfaces and system in package (SiP) for systemizing a plurality of devices in one package. It can be suitably used for mounting.

DESCRIPTION OF SYMBOLS 1 ... Board | substrate 1 ... One main surface, 3 ... The other main surface, 4 ... Through-hole, 5 ... Conductor, 6 ... Through wiring, 7 ... 1st opening part, 8 ... 2nd opening part, 10 ... Through-hole Wiring board, 13 ... resist, 14 ... non-through hole, 15 ... seed layer, 16 ... modified portion, 17 ... one end, 18 ... other end, 19 ... etching solution, 21 ... conductive layer, 22 ... Conductive layer, 23 ... base material, L ... laser beam, T, T ₁ , T ₂ ... perpendicular line.

Claims (3)

A through hole connecting one main surface and the other main surface constituting the planographic substrate is provided, and a through wiring formed by filling the through hole with a conductor is provided. When the through-hole is viewed, the through-hole has a trapezoidal shape with the inner surface of the through-hole as a side, the two sides of the trapezoid are not parallel to each other, and the upper base of the trapezoid Or a through wiring board manufacturing method in which the two sides of the trapezoid are inclined to the same side with respect to two perpendicular lines drawn from two vertices forming the lower base to a straight line including the opposite side,
A step of modifying a region to be a through hole connecting both main surfaces of the substrate by laser irradiation, and forming a modified portion that gradually increases from the other main surface toward the one main surface (A And the modified portion is removed to form a non-through hole having a first opening on the one main surface and an end serving as the second opening existing in the substrate. A step (B), a step (C) of forming a seed layer on the inner wall of the non-through hole, a step (D) of filling a conductor into the non-through hole via the seed layer, and the other And a step (E) of grinding a main surface to form the non-through hole as a through hole and forming the second opening in the other main surface. Method. A through hole connecting one main surface and the other main surface constituting the planographic substrate is provided, and a through wiring formed by filling the through hole with a conductor is provided. When the through-hole is viewed, the through-hole has a trapezoidal shape with the inner surface of the through-hole as a side, the two sides of the trapezoid are not parallel to each other, and the upper base of the trapezoid Or a through wiring board manufacturing method in which the two sides of the trapezoid are inclined to the same side with respect to two perpendicular lines drawn from two vertices forming the lower base to a straight line including the opposite side,
A step of modifying a region to be a through hole connecting both main surfaces of the substrate by laser irradiation, and forming a modified portion that gradually increases from the other main surface toward the one main surface (G ), And removing the modified portion to form through holes having first and second openings in the one and other main surfaces, respectively, and in the other main surface A method of manufacturing a through wiring board, comprising: attaching a conductor layer (I); and filling the inside of the through hole with a conductor via the conductor layer (J). A through hole connecting one main surface and the other main surface constituting the planographic substrate is provided, and a through wiring formed by filling the through hole with a conductor is provided. When the through-hole is viewed, the through-hole has a trapezoidal shape with the inner surface of the through-hole as a side, the two sides of the trapezoid are not parallel to each other, and the upper base of the trapezoid Or a through wiring board manufacturing method in which the two sides of the trapezoid are inclined to the same side with respect to two perpendicular lines drawn from two vertices forming the lower base to a straight line including the opposite side,
A step of attaching a base material having a conductor layer to the other surface of the substrate in contact with the conductor layer (M), and modifying a region to be a through hole connecting both main surfaces of the substrate by laser irradiation And forming a modified portion that gradually increases in thickness from the other principal surface toward the one principal surface, and removing the modified portion to form a modified portion on the one principal surface. (O) forming a through hole having one opening, and having a second opening at a boundary surface where the other main surface and the conductor layer are in contact with each other, and the through hole through the conductor layer And a step (P) of filling the inside of the conductor with a conductor.

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