JP2764628B2 - Electronic circuit board and manufacturing method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention relates to an electronic circuit board directly connected to an LSI silicon chip or an LSI silicon wafer, an inspection board such as a burn-in board, or an extremely fine liquid crystal display panel. The present invention relates to an electronic circuit board having a high-density conductive circuit, such as an electronic circuit board directly connected to a component having a simple circuit, and a method of manufacturing the same.

(Prior art) Conventionally, as a method of connecting an LSI silicon chip or an LSI silicon wafer to an electronic circuit board or an external connection terminal, a wire bonding method of connecting with a metal wire such as gold, or a device hole is formed in advance. A conductor circuit is formed on the tape and the conductor circuit is suspended in the device hole.The TAB method of directly connecting the conductor circuit to the LSI silicon chip, or soldering to one or both of the electronic circuit board and the chip There is a flip-chip connection method in which bumps are formed, and these are brought into direct contact with each other to melt and connect the solder bumps.

(Problems to be Solved by the Invention) Among the above three connection methods, in the wire bonding method and the TAB method, connection can be performed by directly reading connection terminals of a wafer or a chip and performing positioning. However, in the case of the flip chip connection method,
Since the wafer or chip is turned upside down and connected, when connecting to a non-translucent electronic circuit board,
Since the position of the connection terminal cannot be directly read, a method of increasing the distance or width of the connection terminal of the chip to facilitate alignment is conventionally used for connection with such an electronic circuit board. Was. Therefore, in this method,
The connection terminals of the chip could not be fine, and it was difficult to realize high-density mounting.

The present invention has been made in view of the above circumstances, and its purpose is to connect a chip having a fine connection terminal with a non-light-transmitting electronic circuit board with high precision, An object of the present invention is to provide an electronic circuit board capable of high-density mounting, and to provide a manufacturing method capable of easily and efficiently manufacturing the electronic circuit board.

(Means for Solving the Problems) In order to solve the problems as described above, the measures taken by the invention according to claim 1 include “an electronic circuit board (10) having a non-translucent substrate (1). )
A through hole (3) penetrating through the base material (1); a conductor (5b) formed on one surface of the base material (1) while being suspended in the through hole (3); An electronic circuit board (10) comprising: an opening (6) formed in the conductor (5b) so as to be recognizable from the other surface of the substrate (1) through the through hole (3). ) ".

The structure will be described with reference to FIG. An electronic circuit board (10) according to the present invention includes a conductor circuit (5) formed on one surface of a non-translucent substrate (1) in which a through hole (3) penetrating the front and back is formed.
a) A conductor (5b) such as a) is formed, and an opening (6) recognizable through the through hole (3) is formed in the conductor (5b). Then, the opening (6) is inserted into the through hole (3).
Through this, the position of the connection terminal on the substrate side to which the chip is connected can be confirmed with high precision by recognizing it from the other surface side of the substrate (10), so that it can be securely connected to the connection terminal of the wafer or chip. It was made. That is, the opening (6) formed in the conductor circuit (5a) or the like is used as a positioning mark used when connecting a chip or the like.

The through hole (3) preferably has a hole size of 5 mmφ or less. The reason is that if the diameter is larger than 5 mmφ, the interval for supporting the conductor (5b) is widened, and it is difficult to maintain a highly accurate shape of the conductor (5b).

The thickness of the conductor (5b) formed in a suspended state is preferably 5 to 50 μm. The reason is 5μ
When the thickness is smaller than m, the strength of the conductor (5b) is reduced, and the conductor (5b) is easily deformed during use, and it is difficult to maintain a highly accurate shape. Because it becomes. Therefore, suitable conditions are 10 to 35 μm.

Further, the conductor formed in the suspended state (5b)
The shape of the opening is preferably any one of a square, a circle, and a polygon having no convex portion inside. The reason is that the shape of the opening of the conductor (5b) formed in a suspended state can be various shapes as shown in FIG. 2, but the opening (6) as shown in FIG. This is because, in a shape having a convex portion on the inside of the opening, the strength of the convex portion is low, and the shape of the opening (6) tends to lack stability.

As for the conductor (5b), a conductor circuit (5a) having a circuit pattern may be used, or the conductor circuit (5b) may be used.
It may be provided completely differently from a), as long as the opening (6) serving as a positioning mark can be formed.

Next, in order to manufacture the electronic circuit board (10) easily and efficiently, the means adopted by the manufacturing method according to the second aspect of the present invention is as follows: “penetration through the non-translucent base material (1)”; Hole (3),
A conductor (5b) formed on one side of the substrate (1) in a state of being suspended in the through hole (3), and the conductor (5b) is inserted into the conductor (5b) through the through hole (3). A method for manufacturing an electronic circuit board, comprising: manufacturing an electronic circuit board (10) having an opening (6) formed so as to be recognizable from the other surface by the following steps.

(A) a step of forming an adhesive layer (2) on one side of a non-translucent substrate (1); (b) a step of forming a through hole (3) in the substrate (1) of (a); (C) A conductive foil (5) having a resin layer (4) or a glass layer (4) formed on a portion or the entire surface corresponding to the through-hole (3) of (b) through the adhesive layer (2) to the base material. Step (a) of attaching the resin layer (4) or glass layer (4) to the through hole (3) of (b) after attaching the conductor foil (5) to the base material (1). (D) a step of subjecting the conductor foil (5) of (c) to a chemical treatment to form a necessary conductor circuit (5a) and an opening (6) of the conductor (5b); (e) resin Removing the layer (4) or the glass layer (4). It is.

This manufacturing process will be described in more detail with reference to FIGS.

Step (a) is a step of forming an adhesive layer (2) on a non-translucent substrate (1) as shown in FIG. The adhesive layer (2) is a semi-curable sheet such as a prepreg, or a liquid having a relatively high heat resistance such as an epoxy resin, an acrylic resin, a polyimide resin, and a bismaleimide-triazine resin. May be applied. This adhesive layer (2) must be in a state where the adhesive strength is left because the conductive foil (5) is required to be subsequently bonded.

Step (b) is a step of providing a through hole (3) in the base material (1) in step (a), as shown in FIG. Through this through hole (3), the opening (6) (positioning mark) of the conductor (5b) formed on the back surface is read. If the size of the through-hole (3) is too large, the strength of the conductor (5b) (alignment mark) to be formed later decreases and it becomes difficult to maintain the position. Therefore, the preferable size is 5 mm or less.

In the step (c), as shown in FIG. 5, a conductor foil (5) (for example, a metal foil such as copper, gold, or aluminum) is applied to the one formed in the step (b) via the adhesive layer (2). This is the step of bonding. Here, it is necessary to form a resin layer (4) or a glass layer (4) on the adhesive layer (2) side of the through hole (3). The reason is that without this resin layer (4) or glass layer (4), in the next step (d),
When forming a necessary conductor circuit (5a) by chemical treatment or removing an unnecessary portion of the opening (6) (alignment mark) of the conductor (5b), the opening (6)
Since the chemical treatment liquid wraps around the inside of the through hole (3), the conductor (5b) such as the conductor circuit (5a), that is, the alignment mark is further removed from the inside, so that accurate alignment is performed. This is because it becomes difficult to form a use mark. Therefore, the resin layer (4) or the glass layer (4) must be made of a material that can withstand a chemical treatment solution. Materials suitable for this purpose include:
Either using at least one of epoxy resin, polypropylene resin, polyethylene resin, and polycarbonate resin as a main component, a composite of these resins and inorganic fibers, or a glass having a low melting point, such as high lead glass, alumino It is preferable to use silicate glass, lead potassium soda glass, lead silicate glass, lead boron glass, lead boron zinc glass, or the like. In order to form the resin layer (4) or the glass layer (4), as shown in FIG. 5, the resin layer (4) or the glass layer (4) must be formed on the conductive foil (5) in advance and then adhered to the base material (1). Alternatively, as shown in FIG. 6, either a method of forming a resin layer (4) or a glass layer (4) after sticking a conductor foil (5) can be used.

The thickness of the resin layer (4) or the glass layer (4) only needs to be at least 5 μm or more. Since the resin layer (4) or the glass layer (4) must be removed later, the thickness is extremely large. Is not preferred. The thickness of the conductive foil (5) used in this step (c) is preferably 5 to 50 μm. The reason is that if the thickness is less than 5 μm, the mechanical strength is reduced and the precise position cannot be maintained. On the other hand, if the thickness is more than 50 μm, the accurate conductor (5b)
Cannot be formed by chemical treatment.

In the step (d), as shown in FIG. 7, a necessary conductor circuit (5a) is formed by chemical treatment or an opening (6) (alignment mark) of the conductor (5b) is formed. It is a process that does. In this step, the resin layer (4) or the glass layer (4) for preventing the chemical treatment solution from flowing around as described above works effectively.

Step (e) is a step of removing the resin layer (4) or the glass layer (4) as shown in FIG.
In other words, the edge of the conductor circuit (5a) or the alignment mark (the opening (6) of the conductor (5b)) formed by the chemical treatment in the step (d) is exposed to improve the reading accuracy. is there. Therefore, in this step, the resin layer (4) or the glass layer (4) is promptly removed and the conductor circuit (5a) or the conductor (5b) is removed.
(6) (alignment mark) must be removed with a solvent or the like which does not easily erode. As the liquid used for this purpose, it can be used according to the resin layer (4) or the glass layer (4) to be used such as dichloromethane, trichloroethane, hydrochloric acid, sulfuric acid, hydrofluoric acid and the like.

(Operation of the Invention) By the means as described above, the present invention operates as follows.

That is, in the electronic circuit board (10) according to the first aspect of the present invention, as shown in FIG. 9, an alignment mark (opening of the conductor (5b)) recognizable from the opposite surface of the board (1). Since the portion (6) is formed with high precision, it is easy to directly connect to the LSI chip or the wafer.

According to the manufacturing method of the second aspect, in the step of forming the circuit pattern (conductor circuit (5a)), the positioning mark (opening (6) of the conductor (5b)) is formed. Therefore, it is possible to easily and efficiently manufacture an electronic circuit board (10) having a highly accurate alignment mark.

(Example) Next, each Example of this invention is described.

Example 1 First, a substrate (1) was made of a cordierite sintered body (porosity).
This is a ceramic-resin composite base material having a thermal expansion coefficient of 3.8 ppm / ° C., which is filled with an epoxy resin. A prepreg composed of an epoxy-glass fiber composite was laminated on both sides of the substrate (1). Then, it was pressed and adhered in a vacuum autoclave at 120 ° C. for 1 hour at 5 atm. Then, through holes (3) having a diameter of 3 mm were formed in the base material (1) thus formed at four places by a drill. Then, a copper foil (5) (18 μm thick), which was coated and cured on one side with a polycarbonate resin liquid (4) having a diameter of 5 mm and a thickness of 15 μm, was laminated at a position corresponding to the position of the through hole (3). ℃,
It was pressed and adhered in a vacuum autoclave under the condition of 9 atm for 1 hour. Next, a through-hole was formed in this substrate by drilling, and then through-hole plating was performed with chemical copper at 15 μm. As a result, the thickness of the conductor (5b) on the through-hole (3) became 33 μm. Next, a mask film having a square notch of 0.3 mm square was applied to the center of the through hole (3), and etching was performed with a cupric chloride solution to remove the 0.3 mm square portion of the copper foil. Finally, the polycarbonate resin (4) was removed from the substrate with a dichloromethane solution to form an alignment mark as shown in FIG.

The size of the alignment mark thus obtained is 0.
It was 295 x 0.297 mm, and was located with extremely high precision within 6 µm from the set position. Then, as shown in FIG. 9, this alignment mark is recognized from the opposite surface of the substrate (10) through the through hole (3), and 1800 connection terminals formed on the surface of the silicon wafer of 150 mm in diameter are connected to each other. Upon connection, the maximum deviation between the connection terminal of the silicon wafer and the connection terminal (7) on the substrate side was 12 μm, and short-circuit and open connection failure did not occur.

Example 2 The same as Example 1, except that the through holes (3) in Example 1 were φ5 mm and φ7 mm, respectively, and the thickness of the copper foil (5) was etched to 3 μm to reduce the chemical copper thickness. Each recognition result when 0.10 μm is used, when 70 μm copper foil (5) is used or when the chemical copper thickness is 10 μm, and when the opening (6) of the conductor (5b) is set to FIG. Are shown in Table 1.

As shown by these results, it is understood that the substrate (10) of the present invention achieves excellent alignment accuracy.

Comparative Example As a result of connection in Example 1 without using the alignment mark of the present invention, the maximum deviation amount was 48 μm, and 200 or more connection failures occurred.

(Effect of the Invention) As described above, the electronic circuit board according to the first aspect of the present invention
An electronic circuit board having a non-light-transmitting base material, a through-hole penetrating the base material, a conductor suspended on the through-hole, and formed on one surface of the base material, And an opening formed so as to be recognizable from the other surface of the base material through the through-hole. "

Therefore, according to this electronic circuit substrate, even if the substrate is a non-translucent substrate, the alignment mark (opening of the conductor) that can be recognized from the opposite surface is formed with high precision.
It can be easily connected directly to I-chip or wafer. That is, when this electronic circuit board is used, the alignment mark is directly read from the lower surface of the board through the through hole,
Not only LSI chips or wafers, but also various components or modules can be aligned at the top of the board, so space can be used more effectively compared to mounting devices that recognize at the top and align at the top. A compact mounting device can be obtained.

Further, the manufacturing method according to the invention of claim 2 includes a method of: “a through-hole penetrating the non-translucent base material, a conductor formed on one surface of the base material while being suspended in the through-hole, An electronic circuit board, comprising: an electronic circuit board having a conductor and an opening formed so as to be recognizable from the other surface of the base material through the through hole, by the following process.

(A) a step of forming an adhesive layer on one surface of a non-translucent substrate; (b) a step of forming a through hole in the substrate of (a); (c) a portion corresponding to the through hole of (b) Alternatively, a step of sticking a conductor foil having a resin layer or a glass layer formed on the entire surface to the base material via the adhesive layer, or a step of sticking the conductor foil to the base material and (b) applying a resin (D) a step of subjecting the conductor foil of (c) to a chemical treatment to form necessary conductor circuits and conductor openings; (e) removing the resin layer or the glass layer Process. ”Is its structural feature.

Therefore, according to this manufacturing method, the alignment mark (opening of the conductor) can be formed in the step of forming the circuit pattern (conductor circuit), so that the electronic circuit having the accurate alignment mark can be formed. The substrate can be easily and efficiently manufactured.

[Brief description of the drawings]

FIG. 1 is a partial sectional view showing a first embodiment of the electronic circuit board according to the first aspect of the present invention, and FIGS. 2 to 2 are partially enlarged plan views showing respective shapes of openings (positioning marks) of conductors. 3 to 8 are partial cross-sectional views showing the manufacturing method according to the second aspect of the invention in the order of steps, and FIG. 9 is a method for directly connecting chips using the electronic circuit board according to the first aspect. FIG. EXPLANATION OF SYMBOLS 10 ... Electronic circuit board, 1 ... Base, 2 ... Adhesive layer, 3 ...
... through-hole, 4 ... resin or glass layer, 5 ... conductor foil, 5a
... conductor circuit, 5b ... conductor, 6 ... opening, 7 ... connection terminal.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H01L 21/60 311 H05K 13/04

Claims (2)

(57) [Claims] 1. An electronic circuit board having a non-light-transmitting base material, a through-hole penetrating the base material, and a conductor formed on one surface of the base material while being suspended in the through-hole. And an opening formed in the conductor so as to be recognizable from the other surface of the base material through the through hole. 2. A through-hole penetrating a non-translucent base material, a conductor formed on one side of the base material suspended in the through-hole, and a conductor formed through the through-hole through the conductor. A method for manufacturing an electronic circuit board, comprising: manufacturing an electronic circuit board having an opening formed so as to be recognizable from the other surface of a base material by the following steps. (A) a step of forming an adhesive layer on one surface of a non-translucent substrate; (b) a step of forming a through hole in the substrate of (a); (c) a portion corresponding to the through hole of (b) Alternatively, a step of sticking a conductor foil having a resin layer or a glass layer formed on the entire surface to the base material via the adhesive layer, or a step of sticking the conductor foil to the base material and (b) applying a resin (D) a step of subjecting the conductor foil of (c) to a chemical treatment to form necessary conductor circuits and conductor openings; (e) removing the resin layer or the glass layer Process.