JPH04332139A - Manufacture of electronic structure component with junction surface for soldering other article - Google Patents

Abstract

PURPOSE:To easily and effectively form an electronic structure component without labor by plating a primarily processed junction surface for soldering a material to be processed, and secondarily processing a soldering material except the junction surface to be soldered. CONSTITUTION:Junction surfaces 50, 70 for soldering other article of members A, B to be processed, to be scarcely moistened with a primarily processed soldering material, are so plated as to be easily moistened with the soldering material. Then, the members A, B to be processed, for forming a surface part in which a soldering material except the junction surfaces 50, 70 of the plated members A, B, are secondarily processed, the surface parts of the plated members A, B for forming a surface part undesirably adhered with the soldering material are removed, and an electronic structure component is formed. Thus, the component in which the surfaces 50, 70 for soldering other component are plated to be easily wettable with the soldering material and the surface undeisrably adhered with the soldering material except it are not plated, can be easily and effectively formed.

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 an electronic structural component having a joint surface for brazing other articles such as a peripheral wall of a semiconductor housing device to which ceramic terminals are brazed.

0002

2. Description of the Related Art Conventionally, there has been a semiconductor storage device called a metal package in which a peripheral wall of a cavity for accommodating a semiconductor chip is formed of a highly thermally conductive copper-tungsten alloy.

[0003] In this device, a ceramic terminal having a connection line is brazed to a part of the peripheral wall.

By the way, a peripheral wall made of copper-tungsten alloy or the like is difficult to wet with brazing material, so when brazing a ceramic terminal to the peripheral wall, the surface of the peripheral wall is coated with nickel plating, etc. The material is in a state where it is easy to get wet.

[0005]

[Problem to be Solved by the Invention] However, when a ceramic terminal is brazed to the above-mentioned plated peripheral wall, the brazing material for ceramic terminal brazing is applied to a surface other than the joint surface of the peripheral wall to which the ceramic terminal is brazed. , flowed out and adhered to the inner bottom surface of the surrounding wall, etc. The adhering brazing filler metal had various adverse effects on, for example, semiconductor chips bonded to the inner bottom surface of the peripheral wall, stages for mounting the chips, and the like. Specifically, when a semiconductor chip or stage was bonded to the inner bottom surface of the peripheral wall, a gap was created between the bottom surface of the chip or the stage and the inner bottom surface of the peripheral wall due to the brazing material adhering to the inner bottom surface of the peripheral wall. Then, the heat generated by the semiconductor chip cannot be efficiently dissipated to the outside of the semiconductor storage device through the surrounding wall, and the bonding strength of the bonding material decreases due to the silver in the brazing material getting mixed into the bonding material for the semiconductor chip or stage. It was.

[0006] This is because the inner bottom surface of the peripheral wall other than the bonding surface of the ceramic terminal is also plated with nickel or other plating, and these bottom surfaces are easily wetted by the brazing material. This is because the brazing filler metal flows out onto the inner bottom surface of those surrounding walls.

[0007] In order to solve these difficulties,
A method may be considered in which partial plating is applied only to the ceramic terminal brazing joint surface of the peripheral wall. However, recent semiconductor storage devices have become increasingly smaller and more dense, and the shape of their surrounding walls has also become smaller and more sophisticated. Accurately applying partial plating is extremely difficult and virtually impossible.

Another conceivable method is to braze the ceramic terminal to the peripheral wall and then cut, polish, etc. the inner bottom surface of the peripheral wall to remove the brazing material that has flowed and adhered to those surfaces. However, similar to the above, it is extremely difficult to remove the brazing filler metal that has flowed and adhered to the surfaces of small and refined peripheral walls by cutting, polishing, etc. without damaging the ceramic terminals. , making it virtually impossible.

[0009] The same can be said of other small and sophisticated electronic structural parts having bonding surfaces for brazing various other products in which the brazing material is plated with easy wettability.

[0010] The present invention has been made in view of the above problems, and includes plating that is easily wetted by the brazing material on the joint surface for brazing other products, and plating the surface area on which other brazing materials are not desired to adhere. It is an object of the present invention to provide a method for manufacturing an electronic structural component (hereinafter referred to as a manufacturing method) that can easily and accurately form an electronic structural component that is not plated and has a joint surface for brazing other articles.

[0011]

[Means for Solving the Problems] In order to achieve the above object, the manufacturing method of the present invention performs primary processing on a workpiece that is difficult to wet with a brazing material for forming electronic structural parts, and A process of forming a joint surface for brazing other articles, and plating at least the joint surface for brazing of the workpiece that has undergone the primary processing, and a state where the joint surface for brazing is easily wetted by the brazing material. Electronic structural components are manufactured by performing secondary processing on the part of the plated workpiece that forms at least the surface area on which the brazing material is not to be attached, other than the joint surface for brazing. The method is characterized in that it includes a step of forming.

0012

[Operation] In the manufacturing method consisting of the above steps, when plating is applied to at least the joint surface for brazing of the workpiece that has undergone the primary processing, the plating is not applied to the surface of the workpiece other than the joint surface for brazing. Even if it is applied, after that,
When secondary processing is performed on the part of the workpiece that forms a surface area other than the joint surface for brazing of the plated workpiece, where you do not want the solder metal to adhere, you do not want the solder metal to adhere to it. The plated surface portion of the workpiece forming the surface portion can be removed. Then, by applying plating to the joint surface for brazing other articles, it is possible to easily and accurately form an electronic structural component in which the other surface parts to which the brazing material is not desired to be plated are not applied.

[0013]

Embodiments Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a semiconductor storage device using electronic structural components that can be formed by the manufacturing method of the present invention, and specifically shows a perspective view thereof. The semiconductor storage device shown in this figure will be explained below.

In the figure, reference numeral 10 denotes a semiconductor chip housing made of a copper-tungsten alloy, a recently developed first, second, or third molybdenum-based alloy, which has high thermal conductivity and is difficult to get wet with the brazing material. This is a peripheral wall surrounding the cavity 60 for use.

[0015] Here, the first molybdenum-based alloy refers to a molybdenum-based alloy containing 2 to 12% by weight of nickel, 1.5 to 8% by weight of copper, and the balance being molybdenum and unavoidable impurities. is described in Japanese Patent Application No. 2-232792.

[0016] The second molybdenum-based alloy is nickel 2-
This refers to a molybdenum-based alloy having a composition of 12% by weight, 1.5 to 8% by weight of iron, and the balance being molybdenum and unavoidable impurities, the details of which are described in Japanese Patent Application No. 2-232791.

[0017] The third molybdenum-based alloy is nickel 2-
12% by weight, iron 1.5-8% by weight, tungsten 2-1
2% by weight, with the balance being molybdenum and unavoidable impurities, the details of which are described in Japanese Patent Application No. 2-232791.

The peripheral wall 10 has a rectangular box shape with a bottom and a wide opening at the upper end, and has stepped surfaces 14a and 14b on the inside and outside of the left and right side walls 12a and 12b, respectively.

Recesses 16a, 16b are provided in the center portions of the left and right side walls 12a, 12b provided with step surfaces 14a, 14b, and connecting lines 32 are provided in these recesses 16a, 16b.
Ceramic terminals 30 each having a diameter are brazed to each other.

A metal lead 40 is connected to the outer end of the connection line 32 of the ceramic terminal 30.

Peripheral wall 10 including the upper end surface of ceramic terminal 30
A seal ring 20 is brazed to the upper end surface.

The semiconductor storage device shown in FIG. 1 is constructed as described above, and in this device, the peripheral wall 10 can be formed using the manufacturing method of the present invention.

A preferred embodiment in which the peripheral wall 10 of this semiconductor storage device is formed according to the manufacturing method of the present invention will be described below.

A workpiece A in the shape of a rectangular block for forming the peripheral wall 10 is prepared, which is made of a copper-tungsten alloy or a first, second, or third molybdenum-based alloy that is difficult to wet with the brazing material. Then, as shown in FIG. 2, primary processing is performed on the workpiece A to form a ceramic terminal brazing joint surface 50 and a seal ring brazing joint surface 70 on the workpiece A, respectively. ing. Specifically, as shown in FIG. 2, blind hole-shaped vertically elongated notches 52 are respectively provided in the center surface of the left and right ends of the workpiece A using an end mill or the like, and these notches are A ceramic terminal brazing joint surface 50 is formed on a part of the inner circumferential surface of the ceramic terminal 52 . At the same time, the upper end surface of the workpiece A is smoothed by lapping or the like, and a seal ring brazing joint surface 70 is formed on a part of the upper end surface of the workpiece A.

Alternatively, a workpiece B in the form of a long strip block for forming the peripheral wall 10 is prepared, which is made of a copper-tungsten alloy or a first, second, or third molybdenum-based alloy that is difficult to wet with the brazing material. are doing. Then, as shown in FIG. 3, primary processing is performed on the workpiece B to form a ceramic terminal brazing joint surface 50 and a seal ring brazing joint surface 70 on the workpiece B, respectively. ing. Specifically, as shown in FIG. 3, blind cutout holes 52 and vertical holes 54 are formed at predetermined intervals in the longitudinal direction at the center of the surface of the workpiece B using an end mill or the like. A ceramic terminal brazing joint surface 5 is provided in a part of the inner peripheral surface of the notch hole 52 or the vertically long hole 54.
0 respectively. At the same time, workpiece B
The upper end surface is smoothed by lapping or the like, and a seal ring brazing joint surface 70 is formed on a part of the upper end surface of the workpiece B.

Next, the workpieces A and B, which have been subjected to the primary processing, include the ceramic terminal brazing joint surface 50 and the seal ring brazing joint surface 70.
Plating (not shown) such as nickel plating is applied to the entire surrounding surface, and the entire surrounding surface of workpieces A and B, including the joint surface 50 for brazing, is easily wetted by a brazing material such as silver solder. It is said that

Alternatively, the ceramic terminal brazing joint surface 50 and the seal ring brazing joint surface 70, or in addition to these, the workpiece A or B, excluding the upper end surface and a part of the side surface thereof, may be used. Plating (
(not shown) and their brazing joint surfaces 50,
70, or in addition, partial plating (not shown) is applied to the upper end surfaces and side surfaces of workpieces A and B around them, and the joint surfaces 50, 70 for brazing, or in addition The upper end surfaces and side surfaces of workpieces A and B in the vicinity thereof are in a state where they are easily wetted by the brazing material. Then, the ceramic terminal brazing joint surface 50 and the seal ring brazing joint surface 7 of the workpieces A and B
This prevents wasteful plating on the surrounding surface of workpiece A other than 0.

[0028] Next, using an end mill or the like, secondary processing is performed on the plated workpiece A or B on the part of the workpiece A or B that forms the surface portion to which the brazing metal is not desired to adhere. ing. At the same time, other predetermined parts of the workpiece A or B other than the ceramic terminal brazing joint surface 50 and the seal ring brazing joint surface 70 of the workpiece A or B that have been plated are Secondary processing is performed to

Specifically, in the workpiece A shown in FIG. 2, a rectangular cavity 60 with a bottom and a wide upper end is provided in the center of the upper end surface of the workpiece A. . At the same time, step surfaces 14a and 14b are provided inside and outside the left and right ends of the workpiece A, respectively.

In the workpiece B shown in FIG. 3, the workpiece B is cut horizontally into a plurality of pieces by crossing the midway part of the vertically elongated hole 54, as indicated by the dashed line in the figure. are doing. A rectangular cavity 60 with a bottom and a wide upper end is provided at the center of the upper end surface of the workpiece B cut into a plurality of pieces. At the same time, the step surfaces 14a are placed inside and outside the left and right ends of the cut workpiece B.
, 14b are provided respectively.

As shown in FIG. 4, the peripheral wall 10 is shaped like a rectangular box with a bottom and a wide opening at the upper end.
b, and the left and right side walls 12a, 12
b Forming a peripheral wall 10 made of any one of a copper-tungsten alloy, a first, a second, and a third molybdenum-based alloy, with recesses 16a and 16b each consisting of a notch hole 52 and a part of a longitudinal hole 54 in the center. are doing. At the same time, the recess 16a,
The ceramic terminal brazing joint surface 50 on the inner side of the ceramic terminal 16b and the seal ring brazing joint surface 70 on the upper end surface of the peripheral wall 10 are plated to be easily wetted by the brazing metal (the part hatched with broken lines in the figure), and the other An unplated peripheral wall 10 is formed on the inner bottom surface of the peripheral wall 10 to which it is not desired that the brazing material adheres.

The method for manufacturing the peripheral wall 10 shown in FIGS. 2 to 4 consists of the steps described above.

In addition, in this method of manufacturing the peripheral wall 10, step surfaces 1 are formed on the left and right ends of the workpiece A during the primary processing.
4b, or a groove (not shown) for forming the step surface 14b is provided on the left and right end portions of the workpiece B or on the surface of the midway portion thereof, crossing the notch hole 52 and the vertically elongated hole 54. , the trouble of providing those step surfaces 14b may be omitted during secondary processing. However, in such a case, those stair surfaces 14
Unless the surfaces b are covered with a masking member, the peripheral wall 10 is formed with plating applied to the surfaces of the step surfaces 14b.

FIG. 5 shows another semiconductor storage device using electronic structural components that can be formed by the manufacturing method of the present invention, and specifically shows a perspective view thereof. The semiconductor storage device shown in this figure will be explained below.

In the figure, reference numeral 100 indicates a copper-tungsten alloy having high thermal conductivity that is easily wetted by the brazing material;
The bottom plate is made of either a second or third molybdenum-based alloy.

The bottom plate 100 has a flat plate shape, and a thin plate-shaped stage 1 for mounting a semiconductor chip is provided at the center of the upper end surface.
20 are integrally protruded.

A ceramic frame 200 having a substantially rectangular frame shape is mounted around the upper end surface of the bottom plate 100, with a stage 120 fitted inside the ceramic frame 200. Then, the lower end surface of the ceramic frame 200 is brazed to the upper end surface of the bottom plate 100 via a metallized layer 220 which is plated (not shown) and is easily wetted with a brazing material provided on the lower end surface of the ceramic frame 200. And the bottom plate 1
00, the bottom surface of the ceramic frame 200 is hermetically sealed, and a bottomed cavity 600 for accommodating a semiconductor chip is formed inside the ceramic frame 200.

The ceramic frame 200 has an inverted T cross section.
It has a character shape, and there are staircase surfaces 230a, 23 around the inside and outside.
0b.

Step surfaces 230 inside and outside the ceramic frame 200
A, 230b are provided with a plurality of thin strip-shaped connection lines 300 made of metallized and arranged in succession through the inside of the ceramic frame 200.

Stair surface 230 on the outside of ceramic frame 200
A thin strip-shaped metal lead 400 is brazed to the outer end of the connection line 300 provided in FIG.

[0041] The upper end surface of the ceramic frame 200 is plated (not shown) that is easily wetted by the brazing material for cap brazing.
A metallized layer 240 is provided.

The semiconductor storage device shown in FIG. 5 is constructed as described above, and in this device, the stage 120
A bottom plate 100 having an integrally protruding structure can be formed using the manufacturing method of the present invention.

The stage 12 of this semiconductor storage device will be described below.
A preferred embodiment will be described in which a bottom plate 100 having an integrally protruding portion 0 is formed according to the manufacturing method of the present invention.

A workpiece C in the shape of a rectangular block for forming a bottom plate is prepared, which is made of a copper-tungsten alloy or a first, second, or third molybdenum-based alloy and is difficult to wet with the brazing material. Then, as shown in FIG. 6, primary processing is performed on the workpiece C to form a ceramic frame brazing joint surface 500 around the upper end surface of the workpiece C. Specifically, as shown in FIG. 6, a step surface 140 is continuously provided around the upper end surface of the workpiece C using an end mill or the like. A rectangular plate-shaped stage forming member 122 is left at the center of the upper end surface of the workpiece C.

Next, the workpiece C that has been subjected to the primary processing
Plating (not shown) such as nickel plating is applied to the entire surrounding surface of the workpiece C including the step surface 140, so that the entire surrounding surface of the workpiece C including the step surface 140 is easily wetted by the brazing material. There is.

Alternatively, the surrounding surface of the workpiece C, excluding the step surface 140 of the workpiece C, or in addition, the surrounding surface of the stage forming member 122 at the center of the upper end surface of the workpiece C, is coated to prevent adhesion of plating. While covered with a masking member, the surface around the workpiece C is plated, and the step surface 140, or in addition, the side surface around the stage forming member 122 in the vicinity thereof is plated (not shown).
The step surface 140 or, in addition, the side surfaces around the stage forming member 122 in the periphery thereof are made to be easily wetted by the brazing material. This prevents wasteful plating on the surrounding surface of the workpiece C other than that of the workpiece C.

Next, using an end mill or the like, perform secondary processing such as cutting on the upper end surface of the stage forming member 122 that forms the surface portion of the plated workpiece C to which the brazing metal is not desired to adhere. are giving. At the same time, the surrounding side surfaces and bottom surfaces of the workpiece C other than the step surface 140 of the workpiece C to which the above-mentioned plating has been applied are coated with wrapping, etc.
The next processing is being carried out.

[0048] Then, a bottom plate 100 as shown in FIG.
A continuous step surface 140 is provided around the upper end surface, and a thin plate-like stage 120 is integrally protruded from the center of the upper end surface of the bottom plate 100, and is made of copper-tungsten alloy, first, second, or third molybdenum-based alloy. A bottom plate 100 is formed. At the same time, the step surface 140 that constitutes the ceramic frame brazing joint surface 500 of the bottom plate 100 is plated to be easily wetted by the brazing material (the part hatched with broken lines in the figure).
The bottom plate 100 is formed by applying no plating to the upper end surface of the stage 120 and other side surfaces around the bottom plate 100 to which other brazing metals are not desired to be attached.

The method for manufacturing the bottom plate 100 shown in FIGS. 6 and 7 consists of the steps described above.

[0050]

[Effects of the Invention] As explained above, according to the manufacturing method of the present invention, the joint surfaces for brazing other products such as ceramic terminals, seal rings, and ceramic frames are plated to be easily wetted by the brazing material. Electronic structural parts made of workpieces that are difficult to get wet with brazing material, such as peripheral walls of semiconductor storage equipment and bottom plates with integrally protruding stages, which have unplated surfaces where you do not want other brazing materials to adhere. It can be formed easily and accurately without much effort.

[0051] When other articles such as ceramic terminals, seal rings, and ceramic frames are brazed to these joint surfaces for brazing, the surface portion where the base material of the workpiece that is not plated is exposed. The brazing material that is about to leak out can be repelled onto the brazing joint surface, etc. by the exposed surface of the workpiece material that is difficult to wet with the brazing material. Then, the brazing material leaks and adheres to the inner bottom surface of the peripheral wall to which the semiconductor chip and stage are bonded, the upper end surface of the peripheral wall to which the seal ring is brazed, the upper end surface of the stage integrally protruding from the bottom plate to which the semiconductor chip is bonded, etc. , it is possible to reliably prevent various adverse effects.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a semiconductor storage device using electronic structural components that can be formed by the manufacturing method of the present invention.

FIG. 2 is a manufacturing process explanatory diagram when the peripheral wall of the semiconductor storage device shown in FIG. 1 is formed by the manufacturing method of the present invention.

FIG. 3 is a manufacturing process explanatory diagram when the peripheral wall of the semiconductor storage device shown in FIG. 1 is formed by the manufacturing method of the present invention.

FIG. 4 is a manufacturing process explanatory diagram when the peripheral wall of the semiconductor storage device shown in FIG. 1 is formed by the manufacturing method of the present invention.

FIG. 5 is a perspective view of a semiconductor storage device using electronic structural components that can be formed by the manufacturing method of the present invention.

FIG. 6 is a manufacturing process explanatory diagram when the peripheral wall of the semiconductor storage device shown in FIG. 5 is formed by the manufacturing method of the present invention.

FIG. 7 is a manufacturing process explanatory diagram when the peripheral wall of the semiconductor storage device shown in FIG. 5 is formed by the manufacturing method of the present invention.

[Explanation of symbols]

10 Peripheral wall 20 Seal ring 30 Ceramic terminal 40 Lead 50 Ceramic terminal brazing joint surface 52 Notch hole 54 Vertical hole 60 Cavity 70 Seal ring brazing joint surface 100 Bottom plate 120 Stage 200 Ceramic frame 300 Connection line 400 Lead 500 Ceramic Joint surface 600 for frame brazing
Cavity A Workpiece member B Workpiece member C Workpiece member

Claims (1)

[Claims] Claim 1: A step of performing primary processing on a workpiece that is difficult to wet with a brazing material for forming electronic structural parts, and forming a joint surface for brazing other products on the workpiece, and the primary processing. A step of plating at least the joint surface for brazing of the plated workpiece to make the joint surface for brazing easily wetted by the brazing metal, and a step of applying plating to the joint surface for brazing of the workpiece to which the plating has been applied. A joint surface for brazing other products, characterized by comprising the step of forming an electronic structural component by performing secondary processing on a part of the workpiece that forms at least a surface part to which no brazing material is to be attached. A method of manufacturing an electronic structural component comprising: