JP2002011718A - Method for manufacturing ceramic connected substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a ceramic connected substrate capable of preventing a closure of a breaking groove before baking, preventing fusion bonding of the groove at the baking time, further eliminating excess increasing of an opening width of the groove even by deeply inserting a grooving blade and hardly generating a burr when drawing the blade. SOLUTION: The method for manufacturing the ceramic connected substrate comprises the steps of inserting a first groove forming blade 20 having a plate- like part 21 having a predetermined thickness, a distal end 22 having a predetermined cutting edge angle and an intermediate part 23 disposed between the plate-like part and the distal end and having a taper angle smaller than the edge angle of the distal end, from a first main surface 5 side up to the part 23, and forming a first breaking groove 14 at an unbaked ceramic large size element 1 to become many circuit boards after dividing and having a circuit board region 2 including a recess 3 for mounting an electronic component opened at the surface 5 side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a ceramic connecting substrate, and more particularly, to a method of manufacturing a ceramic connecting substrate having a plurality of wiring substrate regions (product parts) which become wiring substrates after division. The present invention relates to a method for manufacturing a ceramic connecting substrate in which a break groove is formed at an outer peripheral boundary of a substrate region.

[0002]

2. Description of the Related Art Conventionally, when mass-producing a small-sized ceramic wiring board (chip carrier), a large number of wiring board areas (product parts) having cavities in one unfired ceramic large format are formed, and each wiring board is manufactured. A V-shaped break groove is formed by a groove forming blade along the outer peripheral boundary line (center line of the seal convex portion) of the region. After that, the unfired ceramic large-size is fired to form a ceramic connecting substrate, then subjected to a desired plating, and finally broken along break grooves (so-called chocolate break), so that it is divided into individual wiring substrates. (See JP-A-2000-77204 and JP-A-2000-141344).

[0003]

Conventionally, as shown in FIG. 5, a parallel plate-like portion 31 having a predetermined thickness is used.
And a groove forming blade 30 having a tip portion 32 having a predetermined cutting edge angle. However, when the break groove is formed using the groove forming blade 30, if the plate-shaped portion 31 is inserted into the unfired ceramic large format 1 (see FIG. 1), the plate-shaped portion 31 is formed when the groove forming blade 30 is pulled out. There is a problem that burrs 34 are generated in the vicinity of the break groove opening because the side surface of the broken break groove is rubbed up (see FIG. 6).

On the other hand, without inserting up to the plate-shaped portion 31,
When the break groove is formed by inserting only the distal end portion 32, the above problem is solved. However, the deeper the distal end portion 32 is inserted, the larger the opening width of the break groove becomes. The area becomes small,
The sealing metallization layer 8 cannot be provided with a sufficient width (see FIG. 7). In recent years, semiconductor chips mounted on a wiring board have been increasingly miniaturized, and accordingly, the wiring board has also been miniaturized, and the width of the seal projection 4 around the cavity 3 has also become narrower. It is important to secure a region (width) for forming the metallization layer 8 for sealing formed on the seal projection 4.

If the tip angle of the tip 32 is reduced as shown in FIG. 8, the opening width of the break groove can be reduced accordingly, but the width at the bottom of the break groove becomes too small, so that the formation of the groove is too small. After the blade is pulled out, the unstrengthened ceramic returns to the original direction due to the elastic force of the large format, that is, the direction in which the break groove is closed, that is, if so-called springback occurs, the formed break groove is closed or fired. There is a drawback that they may be fused or hard to break.

[0006] The present invention has been made in view of such circumstances, and the object thereof is to prevent the break grooves before firing from being closed, and prevent fusion of the break grooves during firing. It is still another object of the present invention to provide a method for manufacturing a ceramic connecting substrate in which the opening width does not become too large even when the groove forming blade is inserted deeply, and burr does not easily occur when the groove forming blade is removed.

[0007]

According to a first aspect of the present invention, there is provided a method of manufacturing a ceramic connecting substrate, comprising a first main surface and a second main surface, wherein a large number of divided substrates are provided after division. The unsintered ceramic large-size, in which the wiring substrate is formed with a wiring substrate region provided with a concave portion for mounting electronic components which is opened on the first main surface side, is formed along the outer boundary line of each wiring substrate region on the first main surface side. Forming a first break groove by inserting a first groove forming blade into the ceramic substrate, and firing the unfired ceramic large-size sheet having the first break groove formed thereon to form a ceramic connecting substrate. The first groove forming blade is located between the plate-shaped portion having a predetermined thickness, a tip portion having a predetermined tip angle, and the tip portion, and a tip angle of the tip portion is provided. An intermediate portion having a smaller taper angle, and Break groove, the first groove forming blade and forming pledged to the intermediate portion.

According to this method, since the first groove forming blade cannot be inserted into the plate-shaped portion, the first groove forming blade does not rub the inside of the first break groove when pulling out the first groove forming blade. Burrs can be prevented from occurring. In addition, since the tip portion has a relatively large included angle and the middle portion has a relatively small angle, the opening width of the first break groove does not become too large even if the first groove forming blade is inserted deeply. In addition, since a certain width can be secured even at the bottom of the break groove, springback before firing and welding during firing can be prevented.

In order to prevent springback and welding, the tip angle of the tip of the first break blade must be
It is preferably at least 30 °, more preferably at least 35 °. Further, the angle of the intermediate portion is preferably 30 ° or less, and more preferably 25 ° or less. In order to prevent the side wall of the break groove from being rubbed, the angle of the intermediate portion is preferably 5 ° or more, more preferably 10 ° or more.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for manufacturing a wiring board according to the present invention will be described in detail with reference to FIGS. First, in the drawing, reference numeral 1 denotes an unfired ceramic large-size (hereinafter, referred to as a multi-cavity) having a first main surface 5 and a second main surface 6 and having a wiring board area (product part) 2 to be each wiring board after division. , Simply referred to as large format). FIG. 1 is a sectional view of a large format 1. At the center of each wiring board region 2, there is provided a cavity (recess) 3 which is stepwise downwardly narrow in a rectangular shape in plan view. Also, the first main surface 5 of the large format 1
On the (upper surface), a seal projection 4 is provided around each cavity 3, and on the upper surface of the seal projection, a sealing metallization layer 8 is formed in a square frame shape in plan view so as to surround the cavity 3. I have.

Such a large format 1 is a ceramic green sheet (having a thickness of 0.25 mm or more) containing alumina as a main component and formed to form the ceramic layers 11, 12 and 13 so that a predetermined number of substrate portions can be formed. 0.3 mm). Then, the metallized paste is cut and punched into a shape corresponding to each ceramic layer, and a metallized paste of W, Mo, or the like, such as a sealing metallized layer 8, a wiring layer, and a common conductive layer for plating is printed. The thus-produced ceramic green sheets are laminated and pressed to obtain an unfired ceramic large format 1 shown in FIG.

Next, the break groove forming step will be described. The first groove forming blade 20 shown in FIG.
1, a tip 22 having a bevel angle of 40 °, and an intermediate portion 23 having a taper angle of 18 °. The first groove forming blade 20 is inserted into the unfired ceramic large format 1 from the first main surface 5 side to the middle of the intermediate portion 23 (see FIG. 3), and pulled out, so that the outer peripheral boundary line of each wiring board region 2 is obtained. A first break groove 14 is formed along 7 (see FIG. 4).

The tip portion 22 has an edge angle of 30 ° or more (40 ° in the present embodiment), so that springback before firing and welding during firing can be effectively prevented. In addition, since the intermediate portion has a taper angle smaller than the blade tip angle (5 ° or more and 30 ° or less, 18 ° in the present embodiment), the opening width 15 does not become very wide even if the first groove forming blade is inserted deep. Therefore, the metallization layer 8 for sealing can be formed with a sufficient width. Further, since the first groove forming blade 20 is inserted halfway into the intermediate portion 23 having a taper angle of 18 °, the first groove forming blade 20 can be removed without being rubbed up, so that burrs are generated near the opening of the first break groove 14. Can be prevented.

The unfired ceramic large format 1 which has been subjected to the break groove forming step as described above is fired, and then nickel plating is applied to necessary portions such as a metallization layer 8 for sealing and a wiring layer. Next, a preform of a brazing material (silver solder) in a square frame shape in plan view corresponding to the metallizing layer 8 for sealing of each wiring substrate region 2 is placed on each metallizing layer 8 for sealing, and heated and melted. Thus, a brazing material is formed on the metallizing layer 8 for sealing.
After that, the metallizing layer 8 for sealing on which a brazing material is previously applied
A seal ring made of Kovar having a quadrangular frame shape in a plan view is placed thereon, and in this state, the brazing material is heated and melted again to complete the brazing of the seal ring.

Large format 1 after brazing of seal ring
After plating the surface of the seal ring and the surface of each wiring layer with Ni plating, Au plating, or the like, it is divided along each first break groove 14 to form a large number of wiring boards (chip carriers). The wiring board is used by, for example, joining a lid to a seal ring after electronic components such as a SAW filter are mounted in the cavity 3.

In the above embodiment, the step of forming the first break grooves 14 only on the first main surface 5 side has been exemplified. However, the groove forming blades (second groove forming blades) are also formed on the second main surface 6 side. ) Is inserted, and the second break groove is formed at a position corresponding to the first break groove 14, since the breakability is further improved. Further, as the second groove forming blade, similarly to the first groove forming blade 20, a blade having a tip portion, an intermediate portion, and a plate-like portion can be used.

Further, in the above-described embodiment, the groove forming blade having only one intermediate portion has been exemplified. However, a groove forming blade having a plurality of intermediate portions having different taper angles may be used. For example, it is also possible to use a groove forming blade having a plurality of intermediate portions such as a tip portion of 40 °, a first intermediate portion of 25 °, and a second intermediate portion of 18 °.

According to the present invention, the break grooves before firing can be prevented from being closed, and the fusion of the break grooves during firing can be prevented. Further, even if the groove forming blade is inserted deeply, the opening width becomes large. It is possible to provide a method of manufacturing a ceramic connecting substrate, which is not too simple and hardly generates burrs when the groove forming blade is pulled out.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an unfired ceramic large format according to the present invention.

FIG. 2 is a sectional view of a main part of a first groove forming blade used in a break groove forming step of the present invention.

FIG. 3 is an explanatory view showing a state in which a first groove forming blade is inserted into an unfired ceramic large format according to the present invention.

FIG. 4 is an explanatory view showing a state in which a first break groove is formed in an unfired ceramic large format according to the present invention.

FIG. 5 is a sectional view of a main part of a conventional groove forming blade.

FIG. 6 is an explanatory view showing a problem when a conventional groove forming blade is inserted.

FIG. 7 is an explanatory view showing a problem when a conventional groove forming blade is pulled out.

FIG. 8 is an explanatory view showing a problem after the conventional groove forming blade is pulled out.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Unfired ceramic large format 2 Wiring board area (product part) 3 Cavity (concave part) 4 Seal convex part 5 1st main surface 6 2nd main surface 7 Perimeter boundary line 8 Sealing metallization layer 11, 12, 13 Ceramic layer 14 First break groove 20 First groove forming blade 21 Plate-like portion 22 Tip portion 23 Intermediate portion

Claims (1)

[Claims] 1. A wiring board region having a first main surface and a second main surface, becomes a large number of wiring boards after division, and has a wiring board region provided with a concave portion for mounting electronic components, which is opened on the first main surface side. A break groove forming step of forming a first break groove by inserting a first groove forming blade into the first main surface side along an outer peripheral boundary line of each wiring board region in the unfired ceramic large format; A firing step of firing the formed unfired ceramic large-size sheet to form a ceramic connecting substrate, wherein the first groove forming blade has a plate-shaped portion having a predetermined thickness, and a tip having a predetermined cutting edge angle. And an intermediate portion located between the plate-shaped portion and the tip portion and having a smaller taper angle than the cutting edge angle of the tip portion. The first break groove includes the first groove forming blade. A ceramic tube, which is formed by inserting the intermediate portion up to the intermediate portion. A method for manufacturing a bonding substrate.