JP2010056496A - Method of forming metallic material in wafer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of forming a metallic material in a wafer, which facilitates filling a through-hole, while reducing an environmental load. <P>SOLUTION: The method of forming the metallic material in the wafer includes disposing the metallic material 20 into the through-hole 11 having a taper formed in a plate like wafer 10. The metallic material 20 having a diameter larger than that of the narrower side of the opening of the through-hole 11 is inserted into the through-hole 11 from the wider side of the opening. The portion of the metallic material 20 protruded from the through-hole 11 is pressed with a jig G to dispose the metallic material 20 into the through-hole 11, while the metallic material 20 is deformed and adhered on the side face of the through-hole 11. The center position of the metallic material 20 is placed in the range of the thickness of the wafer 10 when the metallic material 20 is inserted into the through-hole 11. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a metal material forming method for a wafer in which a through hole is filled with a metal material.

Conventionally, electronic boards on which electronic components are mounted are used in electronic devices. A conductive pattern made of a metal film is formed on the electronic substrate, and an electronic component is mounted on the electronic substrate by bonding a chip component such as a capacitor to the conductive pattern with solder or the like.
In addition to the chip component, the electronic component includes an electronic component having a structure in which various elements are mounted on a container having a recess and the recess is sealed. A plurality of container bodies used for the electronic component are provided in the state of a wafer, and various elements are mounted in the respective concave portions provided in the portion that becomes the container body in the state of the wafer.

Here, the conduction pattern provided on the wafer includes, for example, an external terminal for electrical and mechanical connection with the outside, a mounting pad for conducting with a device such as a crystal resonator element, and a routing pattern. Since the external terminal is provided on the main surface of the wafer opposite to the mounting pad provided on one main surface of the wafer, the external terminal is configured to conduct through the through hole (see, for example, Patent Document 1). .
In order to electrically connect the conductive patterns provided on both main surfaces of such a wafer, electrolytic plating or electroless plating was performed to fill the through holes.

JP 2005-347329 A

However, when the entire inside of the through hole is filled with electrolytic plating or electroless plating, a long time is required until the through hole is filled, so that there is a problem that productivity is deteriorated.
Further, when the through hole is filled with electrolytic plating or electroless plating, the metal material may flow out of the through hole, so that one opening of the through hole may be blocked to prevent this. In this case, there is a problem in that the number of steps for closing one opening of the through hole is increased, and the operation becomes complicated.
In addition, since electrolytic plating and electroless plating use a large amount of chemicals, there is also a problem that the environmental load increases.

  Therefore, an object of the present invention is to provide a method for forming a metal material of a wafer that solves the above-described problems, can easily fill a through hole, and has a low environmental load.

  In order to solve the above problems, the present invention provides a metal material forming method for a wafer in which a spherical metal material is provided in a tapered through hole provided in a plate-shaped wafer, and the narrow side of the opening of the through hole is provided. The metal material having a diameter larger than the diameter of the metal material is put into the through hole from the wide side of the opening, a portion protruding from the through hole of the metal material is pressed with a jig, and the metal material is deformed while being deformed. The metal material is provided in the through hole by being in close contact with a side surface of the through hole.

  Further, the present invention is characterized in that when the metal material is put into the through hole, the center position of the metal material is in the range of the thickness of the wafer.

According to such a metal material forming method for a wafer, the metal material squeezed by the jig can be in close contact with the side surface of the through hole, thereby filling the through hole. That is, the through hole can be easily filled by pressing the metal material into the through hole.
As a result, the through-hole can be filled without using chemicals as in electrolytic plating and electroless plating, so the environmental load can be reduced.

  In addition, when the metal material is put into the through hole, the center position of the metal material is in the range of the thickness of the wafer, so that the metal material is securely adhered to the side surface of the through hole, so that the airtight defect can be eliminated.

  Next, the best mode for carrying out the present invention (hereinafter referred to as “embodiment”) will be described in detail with reference to the drawings as appropriate. Note that each component is exaggerated for easy understanding of the state. In each drawing, the back side is “up” and the near side is “down” with respect to the page.

FIG. 1A is a conceptual diagram illustrating an example of a state before a through hole is formed in a wafer, and FIG. 1B is a conceptual diagram illustrating an example of a state in which a through hole is provided in a wafer. Is a conceptual diagram showing an example in which a base metal film is provided on a wafer, (d) is a conceptual diagram showing an example of a state in which a metal material is put in a through hole, and (e) is a diagram before pressurizing the metal material. It is a conceptual diagram which shows an example of a state, (f) is a conceptual diagram which shows an example of the state which press-fitted the metal material in the through-hole, (g) is filled with the metal material which comprised the metal material. FIG.
FIG. 2 is a conceptual diagram showing an example of a state in which a conductive pattern is provided on the wafer.
As shown in FIG. 1, the method for forming a metal material of a wafer according to an embodiment of the present invention fills the through hole 11 provided in the wafer 10 with a spherical metal material 20.

Here, the wafer 10 shown in FIG. 1 is made of any one of glass, glass ceramic, crystallized glass, silicon (Si), and fired ceramic, and is provided with a plurality of through holes 11.
In addition, this wafer 10 may be a plate-like member for individual parts, or a collective substrate in which a plurality of these plate-like members are collected. For ease of explanation, the wafer 10 will be described as an aggregate substrate made of quartz.

The through hole 11 shown in FIG. 1B is formed by, for example, a conventionally known photolithography technique and etching technique. The through hole 11 may be formed by a sand blast technique. In order to make the explanation easy to understand, the case where the through hole 11 is formed by the sandblasting technique will be described.
In the through hole 11, the diameter of one opening that has started forming the through hole 11 is larger than the diameter of the other opening that has finished forming the through hole 11. In other words, the through hole 11 is formed so as to increase in diameter from one main surface side toward the other main surface side, that is, tapered.
Further, it is preferable that the radius R1 on the wide side of the opening of the through hole 11 has a relationship of R1 <T, where T is the thickness of the wafer 10.

The metal material 20 shown in FIG. 1D is made of, for example, Au (gold). The metal material 20 is formed in a spherical shape, and is formed in such a size that the center position of the metal material 20 is located in the range of the thickness of the wafer 10 when inserted into the through hole 11. That is, the center position of the metal material 20 is located inside the wafer 10.
For example, when the radius R1 on the wide opening side of the through hole 11 is A and the radius R2 of the narrow opening is A / 2, the metal material 20 can be obtained by setting the radius R3 of the metal material 20 to A × 3/4. The center position of is located inside the wafer 10.

The metal material 20 is sized so that a part of the metal material 20 protrudes from the wafer 10 before being inserted into the through hole 11 before press-fitting described later.
The metal material 20 is formed in such a size when the center position of the metal material 20 is not within the thickness of the wafer 10, the volume of the metal material 20 becomes larger than the volume of the through hole 11 and press-fitted. Thereafter, the wafer 10 may protrude from the through hole 11 and be damaged. Further, even if the center position of the metal material 20 is within the thickness of the wafer 10, if there is no portion protruding from the wafer 10, press fitting cannot be performed, and the metal material 20 cannot be deformed to fill the through hole 11.
Therefore, as described above, the metal material 20 is preferably formed so that a part thereof protrudes from the wafer 10 and the center position is within the thickness of the wafer 10.

Next, a method for forming a metal material on a wafer according to an embodiment of the present invention will be described.
First, as shown in FIGS. 1A and 1B, the through holes 11 are formed by a photolithography technique, an etching technique, or a sand blast technique.
As shown in FIG. 1C, a base metal film forming step of forming a base metal film C on the formed wafer 10 having the through holes 11 by vapor deposition is performed.
At this time, the base metal film C is also provided inside the through hole 11 by vapor deposition.
For the base metal film C, Cr, Ni, Nichrome, Cu, Au, Ag, Ti, or the like can be used.

In this state, as shown in FIG. 1D, the wafer 10 is fixed to a predetermined mounting table with the wide opening of the through hole 11 facing upward.
A metal material installation step of putting the metal material 20 into the through hole 11 from the wide side of the opening of the through hole 11 is performed. Here, when there are a plurality of through holes 11, the metal material 20 is put into all the through holes 11.
At this time, a part of the metal material 20 protrudes from the wafer 10.
The through hole 11 of the wafer 10 has a tapered shape. Therefore, the metal material 20 stops in the through hole 11 while being in contact with the side surface of the through hole 11.

Here, as shown in FIG. 1 (e), a jig G having a flat surface is prepared, and the flat surface of the jig G is applied to a portion protruding from the through hole 11 of the metal material 20. Then, as shown in FIG. 1 (f), a pressurizing process is performed in which pressure is applied as it is toward the wafer 10. Thus, the metal material 20 is brought into close contact with the side surface of the through hole 11 while being deformed.
That is, the metal material 20 enters the through hole 11 using the point where the metal material 20 is in contact with the side surface of the through hole 11 as a support point. As a result, the metal material 20 is bonded to the base metal film C provided on the side surface of the through hole 11 and is in close contact with the side surface with high airtightness.
Therefore, as shown in FIG. 1G, the metal material 20 is in a state where the through hole 11 is filled. As a result, the metal material 20 can be used for electrical connection of the conductive patterns P provided on both main surfaces of the wafer 10, as shown in FIG.

According to such a metal material forming method for a wafer, the metal material 20 squeezed by the jig G can be in close contact with the side surface of the through hole 11 to fill the through hole 11. That is, the through hole 11 can be easily filled by press-fitting the metal material 20 into the through hole 11.
Thereby, since the through-hole 11 can be filled without using chemicals like electrolytic plating or electroless plating, the environmental load can be reduced.
Further, when the metal material 20 is put into the through hole 11, the center position of the metal material 20 is in the range of the thickness T of the wafer 10, so that the metal material 20 is securely adhered to the side surface of the through hole 11 after being press-fitted. , Airtightness can be eliminated.

  In addition, although embodiment of this invention was described, this invention is not limited to the said embodiment. For example, the material of the metal material 20 is not limited to Au, and a metal material that can conduct with the conduction pattern can be used. For example, Cu, Al, gold tin, gold germanium, solder balls, or the like can be used.

(A) is a conceptual diagram which shows an example of the state before forming a through-hole in a wafer, (b) is a conceptual diagram which shows an example of the state in which the through-hole was provided in the wafer, (c) is a wafer It is a conceptual diagram which shows an example which provided the base metal film in (d) is a conceptual diagram which shows an example of the state which put the metal material in the through-hole, (e) is a state before pressurizing a metal material. It is a conceptual diagram which shows an example, (f) is a conceptual diagram which shows an example of the state which press-fit the metal material in the through-hole, (g) is the state which filled the through-hole with the metal material which comprised the metal material It is a conceptual diagram which shows an example. It is a conceptual diagram which shows an example of the state which provided the conduction | electrical_connection pattern in the wafer.

Explanation of symbols

10 Wafer 11 Through-hole 20 Metal material G Jig C Base metal film

Claims (2)

A metal material forming method for a wafer in which a spherical metal material is provided in a tapered through hole provided in a plate-shaped wafer,
Put the metal material having a diameter larger than the diameter of the narrow side of the opening of the through hole into the through hole from the wide side of the opening,
Apply pressure to the part of the metal material protruding from the through hole with a jig,
A method of forming a metal material on a wafer, wherein the metal material is provided in the through hole by bringing the metal material into close contact with a side surface of the through hole while deforming the metal material.   The method for forming a metal material of a wafer according to claim 1, wherein when the metal material is put in the through hole, the center position of the metal material is in the range of the thickness of the wafer.

Images