JP2617518B2 - Ceramic package and method of manufacturing the same - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a ceramic package used for a semiconductor device and the like and a method of manufacturing the same.

(Prior art) Ceramic packages containing semiconductor elements, etc.
Good element attachment property for element attachment part and internal lead part,
For the purpose of imparting wire bonding properties or the like, or improving the corrosion resistance and solderability of the external lead portion and the like, plating is performed by plating such as gold plating at necessary places.

FIG. 4 shows an example of a conventional ceramic package. FIG. 4 (a) is a cross-sectional view of the internal lead pattern, and 1 is an internal lead pattern.

In addition, since plating such as gold plating is usually performed by electrolytic plating, the end of each internal lead pattern 1 pulled out to the side surface of the substrate 2 is connected to the substrate as shown in the side view of FIG. Conduction is provided collectively by the side surface patterns 3 formed on the side surfaces, and a contact at the time of plating may be formed by the side surface patterns 3.

(Problems to be Solved by the Invention) As described above, in the ceramic package, the fourth
As shown in the figure, since the side pattern 3 is formed to make contact with plating, a side pattern is formed on the side of the substrate before plating, and the side pattern is removed after plating to remove the side pattern. It is necessary to eliminate the short circuit of the internal lead pattern.

By the way, the side pattern 3 is formed by screen-printing a metallized paste on the side surface of the laminated green sheet. However, conventionally, the printing surface of the side pattern 3 is different from the printing surface of the wiring pattern of the green sheet. Because it is the side surface of the green sheet laminate, the side pattern must be printed in a process different from the wiring pattern, and there is troublesome handling such as re-chucking the green sheet laminate, and after plating. However, it is necessary to remove the side pattern by grinding or the like, but it is necessary to re-chuck the substrate similarly, and there is a problem that the operation becomes very complicated.

FIG. 4 (c) is a side view of the conventional ceramic package after the side pattern has been removed. After the side pattern has been removed, the lead end 4 of the internal lead pattern 1 is exposed on the side of the substrate in a dot-like manner. I do. Such a ceramic package is often mounted by inserting a lead into a circuit board for an electronic device or the like after being mounted with a jig after a semiconductor element or the like is mounted. When the side surface is sandwiched, static electricity flows to the semiconductor element or the like via the leading end exposed on the side surface of the substrate of the internal lead pattern, or the leading end is short-circuited, thereby destroying the function of a semiconductor device or the like on which the semiconductor element is mounted. Or deterioration.

FIG. 4 (d) is a partial cross-sectional view of an example in which a grinding recess 5 is provided on the side surface of the substrate so that the drawer end 4 does not contact the insertion jig or the like in order to solve this problem. However, forming the grinding concave portion 5 on the side surface of the substrate in this way is extremely complicated in terms of work.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to make it possible to easily form a conductive pattern portion for plating and to remove the conductive pattern portion after plating. It is an object of the present invention to provide a ceramic package which can be easily manufactured and a method of manufacturing the same.

(Means for Solving the Problems) The present invention has the following configuration to achieve the above object.

That is, in a method of manufacturing a ceramic package formed by laminating and firing a plurality of green sheets, a green sheet on which a wiring pattern such as an internal lead pattern is formed and a green sheet on which a conductive pattern portion for plating is formed to be conductive to the wiring pattern. A sheet is laminated to form a green sheet laminate in which the conductive pattern portion is exposed at the peripheral portion of the upper surface or the lower surface, and the green sheet laminate is fired to form a substrate, and a contact is made by the conductive pattern portion. After plating the wiring pattern, the periphery of the substrate on which the conductive pattern is formed is chamfered to remove the conductive pattern.

Further, the conductive pattern portion is electrically connected to the wiring pattern via a via formed in the green sheet.

Further, in a ceramic package formed by stacking and firing the plurality of green sheets, an end of the wiring pattern after removing a conductive pattern portion for plating that is conductive to a wiring pattern such as an internal lead pattern is formed on a substrate. It is characterized in that it is exposed at the chamfered peripheral portion of the upper surface or the lower surface.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 (a) and 1 (b) are explanatory views showing a method for manufacturing a pin grid array (PGA) type ceramic package according to the present invention.

In the figure, reference numeral 10 denotes a ceramic substrate formed by laminating and firing green sheets, and reference numeral 12 denotes an internal lead pattern formed of a metallized layer formed on the substrate 10. The internal lead pattern 12 is printed in a predetermined wiring pattern on a green sheet before lamination forming the substrate 10 using a metallizing paste.

Then, the internal lead pattern 12 is drawn and printed so as to reach the periphery of the substrate 10 when printing the wiring pattern of the green sheet, and the leading end of each internal lead pattern 12 drawn to the periphery of the substrate 10 is drawn. The conductive pattern portion 14 that is short-circuited and made conductive is printed.

A green sheet for forming an upper layer substrate 16 is further laminated on the green sheet for forming the substrate 10, and a seal pattern 19 made of a metallized layer is formed on the upper surface of the upper layer substrate 16 and the conductive pattern portion is formed. The substrate 14 is formed smaller than the substrate 10 so as to be exposed around the upper substrate 16.

The green sheets forming the substrate 10 and the upper substrate 16 are laminated and fired, and then subjected to electroless nickel plating.The leads 18 are joined by silver brazing, and then subjected to electrolytic nickel plating. Will be applied. At the time of plating, the conductive pattern portion 14 is used as a contact for plating.

FIG. 1 (b) shows a state where the substrate after plating is ground, and the conductive pattern portion 14 provided on the peripheral portion of the substrate 10 is shown.
Shows a state in which is removed by grinding. Conduction pattern section
By removing 14, each internal lead pattern 12 is separated independently. In this embodiment, the conductive pattern portion 14 is ground obliquely so as to bevel the peripheral portion of the substrate 10.
Has been removed. Reference numeral 20 denotes an oblique removal portion formed by grinding.

FIG. 1 (c) shows another embodiment in which the conductive pattern portion 14 is ground, in which a concave portion 22 is formed in the peripheral edge of the upper surface of the substrate 10 on which the conductive pattern portion 14 is formed and ground. It is.

According to the method for manufacturing a ceramic package described above,
Since the conductive pattern portion 14 for plating is on the same surface as the printed surface of the wiring pattern such as the internal lead pattern 12, the conductive pattern portion 14 can be printed simultaneously with the printing of the internal lead pattern 12 and the like, and the conductive There is an advantage that an operation process for printing the pattern portion is not required.

Also, the work to grind the conductive pattern after plating,
It is only necessary to grind the top and bottom edges of the substrate in the same direction while holding the chuck, which is extremely efficient compared to the work of re-chucking and grinding each conductive pattern on the side of the substrate. Can be performed. Further, the shapes shown in FIGS. 1 (b) and 1 (c) are in positions where the drawn ends of the internal lead patterns 12 are not in direct contact with each other when the side surface of the substrate is sandwiched by an insertion jig or the like. Does not adversely affect the functions of the semiconductor device or the like due to static electricity.

Although FIG. 1 shows an example in which one upper layer substrate is provided on the substrate 10, the same applies to the case where a plurality of upper layer substrates are provided.
A conductive pattern portion is provided on a peripheral portion of each green sheet to be laminated, and the size of the upper green sheet is gradually reduced from the size of the lower green sheet, so that the respective lower conductive patterns are exposed to the outside. And so on
The conductive pattern may be removed by grinding after plating.

Note that the conductive pattern portion in this specification refers to a portion for performing plating by short-circuiting a portion where predetermined plating is performed, including a seal pattern for a cap seal provided on the substrate surface in addition to the internal lead pattern 12. The wiring pattern is a pattern having conductivity, and a wiring pattern is a pattern having a portion where required plating required for a ceramic package is applied.

FIG. 2 shows another embodiment in which a conductive pattern portion for plating is provided.

In this example, the upper substrate 16a is formed to have the same size as the substrate 10, and the internal lead patterns 12 are formed via the vias 24.
It is electrically connected to the conductive pattern portion 14 provided on the peripheral portion of the upper surface of the portion a. In this case, the conductive pattern portion 14 is a seal pattern
Since it is on the same plane as the printing surface of 19, the conduction pattern portion 14 can be printed simultaneously with the printing of the seal pattern 19. FIG. 2 (b) shows a state where the conductive pattern portion 14 is ground and removed after plating, and the ground surface 26 is obliquely removed.

FIG. 2 (c) is a side view of the substrate after grinding, and shows the ground surface.
The lead end 28 of the internal lead pattern 12 is exposed in a dot-like manner at 26, but since the lead end 28 is at a position where the insertion jig and the like do not come into contact during handling, the influence of static electricity or the like is prevented.

FIG. 3 shows an example in which two upper substrates are stacked on the substrate 10. In this case as well, the internal lead patterns 12a and 12b are provided with conductive patterns 14 provided on the uppermost substrate via vias 24a and 24b, respectively. Is conducted. The removal of the conductive pattern portion 14 by grinding after plating is the same as in the above-described example, and an oblique removal portion is provided on the ground surface, or a concave portion is provided on the upper surface of the substrate as shown in FIG. You may.

Vias 24 filled with conductors shown in FIGS.
When conducting with the conductive pattern portion 14 using a conductive pattern portion 14, it is not necessary to prepare green sheets having different sizes when laminating a plurality of green sheets.
Need not be formed on each green sheet, the work of grinding the conductive pattern portion 14 only requires grinding the uppermost conductive pattern portion 14, and the area for grinding the conductive pattern portion 14 is small. There are advantages such as.

Further, in the conventional ceramic package, since the corner portion is chamfered to prevent chipping of the corner portion of the ceramic substrate due to impact or the like, the grinding of the conductive pattern portion can be performed together with this chamfering work, and the work process can be reduced. Also has the advantage of being simple.

In the above embodiment, the conductive pattern portion 14 is provided on the peripheral portion of the upper surface opposite to the surface on which the leads 18 are erected,
The lead 18 may be provided on the periphery of the same lower surface as the surface on which the lead 18 is erected, and may be similarly removed.

In addition to the method of removing the conductive pattern portion after the plating, the conductive pattern portion can be removed by being chemically dissolved by an etching process in addition to the removal by grinding. For example, in the case of gold plating, the metallized layer can be removed by etching after the gold plated layer is chemically stripped.

In the above embodiment, a pin grid array (PGA) type ceramic package was described. However, the manufacturing method is not limited to this package. The present invention can be similarly applied to a package component or the like in which it is necessary to remove the conductive pattern after the operation is performed.

For example, even in the case of a motherboard type ceramic package in which a plurality of semiconductor devices using a ceramic package are mounted, similarly to the above ceramic package, a green sheet provided with a predetermined wiring pattern is formed by laminating. A conductive pattern portion is provided on the upper surface, and the conductive pattern portion and a lead pattern provided on each layer are configured to be conductive via vias, so that conduction for plating can be achieved. Can be ground in the same manner as described above.

As described above, the present invention has been described variously with reference to the preferred embodiments. However, the present invention is not limited to these embodiments, and it goes without saying that many modifications can be made without departing from the spirit of the invention. That is.

(Effect of the Invention) According to the method for manufacturing a ceramic package of the present invention,
The conductive pattern portion for plating is provided on the peripheral portion of the upper surface or the lower surface of the substrate, and the conductive pattern portion is formed at the same time as forming the wiring pattern, so that the conventional conductive pattern portion is formed. Work process becomes unnecessary.

Also, when removing the conductive pattern portion, it can be removed only by grinding in the same direction in a plane, and can be performed together with the chamfering work of the substrate, so that the working efficiency can be greatly improved.

Also, after the substrate is chamfered and the conductive pattern portion is removed, the end of the wiring pattern is exposed at the periphery of the chamfered substrate. , The influence of static electricity or the like can be eliminated, and handling such as mounting on a mounting substrate becomes easy.

According to the method of conducting the wiring pattern and the conduction pattern portion via the via, the conduction pattern portion can be formed particularly easily in a package formed by laminating a plurality of green sheets on which the internal lead patterns are formed. In addition to this, there is a remarkable effect that the conductive pattern portion can be easily removed.

[Brief description of the drawings]

1 (a), 1 (b) and 1 (c) are explanatory views showing a method for manufacturing a ceramic package according to the present invention, and FIGS.
(B), (c) and FIG. 3 are explanatory views showing another method of manufacturing the ceramic package, and FIGS. 4 (a), (b),
(C), (d) is explanatory drawing which shows the manufacturing method of the conventional ceramic package. 1 ... internal lead pattern, 2 ... board, 3 ... side pattern, 4 ... draw-out end, 5 ... ground recess, 9 ... seal pattern, 10 ... ceramic substrate, 12 ... internal lead pattern, 14 …… Conduction pattern part, 16 …… Upper layer substrate,
19: seal pattern, 20: diagonally removed portion, 22: concave portion, 24: via, 28: drawn end.

Claims (3)

(57) [Claims] 1. A method of manufacturing a ceramic package, comprising laminating and firing a plurality of green sheets, wherein a green sheet on which a wiring pattern such as an internal lead pattern is formed and a conductive pattern portion for plating which is conductive to the wiring pattern. The formed green sheet is laminated to form a green sheet laminate in which the conductive pattern portion is exposed at the peripheral portion of the upper surface or the lower surface, and the green sheet laminate is fired to form a substrate. A method of manufacturing a ceramic package, comprising: removing a conductive pattern portion by chamfering a peripheral portion of a substrate on which the conductive pattern portion is formed after plating the wiring pattern by taking a contact. 2. The method according to claim 1, wherein the conductive pattern portion is electrically connected to the wiring pattern via a via formed in the green sheet. 3. In a ceramic package formed by laminating and firing a plurality of green sheets, an end of the wiring pattern after removing a conductive pattern portion for plating which is conductive to a wiring pattern such as an internal lead pattern, A ceramic package which is exposed at a chamfered peripheral portion of an upper surface or a lower surface of a substrate.