JP2598685B2 - Method and apparatus for manufacturing solder ball carrier - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing a solder ball carrier capable of uniformly and collectively forming a large number of fine solder bumps on high-density connection pads of a semiconductor device. .

[Conventional technology]

In the conventional method of manufacturing a solder ball carrier,
As a method of supplying solder to the semiconductor mounting portion, in addition to generally known solder vapor deposition and solder plating, as shown in FIG. 15 (see JP-A-60-234396), a groove is formed in the substrate 19. A method has been proposed in which the solder paste 20 is filled, heated to form a ball, and then supplied to the mounting portion.

[Problems to be solved by the invention]

In the prior art, when Sn-based solder is vapor-deposited on a substrate by a solder vapor deposition method, it takes a long time to obtain a predetermined amount because of the relationship between Sn vapor pressure, that is, the melting temperature is high. In addition, the method using solder plating or solder paste printing is a mixture of both, so that the plating film thickness and the solder particle size fluctuate greatly. There is a problem that the formation of connection bumps greatly reduces connection reliability.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method and an apparatus for manufacturing a high-precision solder ball carrier capable of collectively forming a small, uniform and fixed amount of a large number of solder bumps on a semiconductor mounting portion having a high-density connection pad portion. It is in.

[Means for solving the problem]

In order to achieve the above object, a method of manufacturing a solder ball carrier according to the present invention includes punching a through hole in a sheet that does not react with the solder and melting the sheet into a molten solder bath and pressing the solder into the through hole. The press-fit solder is shaped, cooled and solidified.

The solder ball carrier manufacturing equipment includes a lifting mechanism that lifts and lowers the sheet into the molten solder bath, a plurality of rotating rolls that press the solder into the through holes in the sheet, and a structure that shapes, cools, and solidifies the press-fit solder. The rotating roll is provided in or on a bath of solder in a molten solder bath.

The structure consists of a shaping unit that is provided adjacent to the rotating roll and shapes the press-fit solder pressed into the through-holes in the sheet, and a cooling unit that cools and solidifies the shaped solder. And a control mechanism for interlocking the operations of the rotating roll and the structure.

Further, the rotating roll may be formed of ceramics, and may be formed by coating a metal material having a small melting reaction with solder or a coating of the metal material on the surface.

And the sheet is formed so that the vertical cross-sectional area of the open end on one side of the through hole is larger than the vertical cross-sectional area of the open end on the other side,
The vertical cross-sectional shape of each open end of the through hole may be formed in an asymmetric trapezoid or a flat circular shape with respect to a tangent line in contact with each other.

In addition, a sheet with through holes is placed on the preheating plate, and solder dripped from one side of the sheet is pressed into the through holes by moving the rotating roll, and the pressed roll solder is shaped by following the rotating roll, followed by cooling and solidification. The method may be a method of manufacturing a solder ball carrier to be used, and a preheating plate on which a sheet is placed, a supply jig that moves while dripping solder from one side of the sheet, and at least one rotation that moves while pressing the solder into the sheet. An apparatus for manufacturing a solder ball carrier including a roll and a structure that moves following the rotating roll to shape the press-fit solder and cool and solidify may be used.

[Action]

According to the present invention, the rotating roll installed in the molten solder bath or on the bath surface of the method and apparatus for manufacturing a solder ball carrier is free from rotation in the normal direction when the sheet held by the elevating mechanism is released and lowered. When the sheet is lifted, the sheet is rotated by the left and right rotating rolls so as to apply a load pressure to the sheet. When the elevating mechanism descends, the structure for shaping, cooling, and solidifying is separated from the sheet to the left and right, and sandwiches the sheet with a constant pressure immediately before the sheet ascends via the rotating roll. Next, the solder that has been raised and injected into the through holes is cooled and solidified in the cooling unit while the thickness of the sheet or more is removed in the shaping unit.

Then, the operation of the structure and the rotating roll for shaping, cooling and solidifying according to the operation of the elevating mechanism for holding the sheet are interlocked with each other.

〔Example〕

One embodiment of the present invention will be described with reference to FIGS.

As shown in FIGS. 1 to 4, a method for manufacturing a solder ball carrier is as follows. A through hole 1A is formed in a sheet 1 that does not react with the solder 2 by melting, and the sheet 1 is immersed in a molten solder bath 3. The solder 2 is press-fitted into the through hole 1A, and the press-fitted solder 2A is shaped, cooled and solidified.

The ball carrier manufacturing apparatus includes a lifting mechanism 7 that lifts and lowers the sheet 1 into the molten solder bath 3, a plurality of rotating rolls 5 that presses the solder 2 into the through holes 1 </ b> A of the sheet 1,
A structure 9 for shaping and cooling / solidifying the press-fit solder 2A is provided, and the rotating roll 5 is provided in the bath of the solder 2 in the molten solder bath 3 or on the bath surface.

The structure 9 is provided adjacent to the rotating roll 5 and includes a shaping unit 9A for shaping the press-fit solder 2A pressed into the through hole 1A of the sheet 1, and a cooling unit 9B for cooling and solidifying the press-fit solder 2A after shaping. And a control mechanism 12 for interlocking the operation of the rotating roll 5 and the structure 9 with an operation signal of the lifting mechanism 7.
Is provided.

Further, the rotating roll 5 may be formed of ceramics, and may be formed by coating a metal material having a small melting reaction with the solder 2 or the metal material on the surface.

As shown in FIGS. 12 and 13, the sheet 1 is formed such that the vertical cross-sectional area of the open end on one side of the through hole 1A is larger than the vertical cross-sectional area of the open end on the other side.
The vertical cross-sectional shape of each open end of 1A may be formed in an asymmetric trapezoidal or semicircular shape with respect to a tangent line tangent to each other.

Further, as shown in FIG. 14, a sheet 1 having a through hole 1A is placed on a preheating plate 3A, and solder 2 dropped from one surface of the sheet 1 is pressed into the through hole 1A by moving a rotating roll 5. A method of manufacturing a solder ball carrier that shapes the press-fit solder 2A by following the rotating roll 5 and cools and solidifies the solder 2A may be used. Alternatively, the preheating plate 3A on which the sheet 1 is placed and the solder 2 may be dropped from one surface of the sheet 1 A supply jig 13 that moves while moving E, at least one rotating roll 5 that moves while pressing the solder 2 into the sheet 1,
An apparatus for manufacturing a solder ball carrier including a structure 9 that moves E following the rotating roll 5 to shape the press-fit solder 2A and cool and solidify the solder 2A may be used.

 Next, the operation of the present embodiment will be described.

A sheet 1 (for example, stainless steel or ceramic thin plate) that does not directly react with the solder 2 by melting is formed into a small conical through-hole corresponding to a minute pad portion of a semiconductor.
1A is drilled and press-fit solder is inserted into this through hole 1A.
The solder ball carrier is manufactured by press-fitting 2A. In this case, the amount of solder must be controlled with high precision in order to form minute solder bumps on the minute pads of the semiconductor. For this purpose, the press-fit solder 2A needs to be shaped so as to have the same thickness as the sheet 1.

As shown in FIG. 4, the heating element 4 of the molten solder bath 3
Two heat-resistant rotary rolls 5 are placed on a solder bath of, for example, Sn-40 wt% Pb (melting point: solid phase: 183 ° C., liquid phase: 190 ° C.) melted by heating. In this case, the solder 2 is heated and maintained at about 200 ° C.

On the other hand, above the molten solder tank 3, a sheet 1 having minute through holes (through holes), for example, a thin plate made of stainless steel or ceramics, is held by an elevating function 7 having an elevating function of an ascending and descending arrow A. Immersed in the molten solder 2 through the space between the rotating rolls 5. In this case, the rotating roll is free to rotate left and right while the movement of the rotating direction arrow B, that is, the rotating operation in the normal direction is stopped. Immediately before lifting the sheet 1 from the molten solder bath 3, the side surface of the sheet 1 is structured by a structure 9 having a solder shaping section 9 A having an acute angle and a cooling section 9 B having a cooling water flow path 11 therein. It is sandwiched with a constant pressure so that excess solder other than sheet thickness can be shaped. When the sheet is lifted from the molten solder tank 3 in this state, the rotating roll 5 rotates as indicated by the normal rotation direction arrow B. By pulling up the sheet 1 in this manner, a solder ball carrier can be easily manufactured.
The structure 9 having the sharpening section and the cooling section and the rotating roll 5 are controlled by the control device 12 in conjunction with each other.

FIGS. 5 to 9 show the movement of each part when manufacturing the solder ball carrier.

As shown in FIG. 5, when the lifting mechanism 7 holding the sheet 1 descends, the structure 9 including the sharp shaping section and the cooling section is separated to the left and right of the sheet 1 and
The rotary roll 5 for press-fitting the solder into the through-hole moves freely in the reverse rotation direction C at the time of press-fitting and guides the sheet 1 into the melted solder 2.

FIG. 6 shows a state in which the through hole, which is the main part of the sheet 1, has penetrated into the molten solder bath. In this state, the molten solder has not yet completely entered the through hole.

FIG. 7 shows a state in which the sheet begins to be pulled out of the molten solder bath, and the rotating roll moves the molten solder onto the sheet.
And rotate B while press-fitting. Immediately before that, a structure 9 having a sharp shaping section and a cooling section is provided with a horizontal slide D.
Then, each side of the sheet is pressed with a constant pressure. In this state, the sheet is pulled up by the elevating mechanism 7, so that the excess press-fit solder on the sheet surface is cooled and solidified in the cooling unit while being shaped and removed, and is passed through the steps shown in FIGS. The press-fit solder 2A is filled and shaped to form a solder ball carrier.

The operation of another embodiment of the present invention will be described with reference to FIG.

As shown in FIG. 10, the solder 2 in the molten solder bath 3
On the bath surface, a high-temperature rotating roll 5, for example, a ceramic material, or a metal material having a low melting reaction with the solder 2 or a ceramic formed by coating a metal having a low melting reaction with the solder 2 is provided. A sheet 1 having a through hole is inserted between the respective rotating rolls, and when the sheet 1 is pulled up, the solder 2 melted by the rotating rolls is press-fitted, and then the solder is cooled and solidified in a cooling atmosphere for mass production. This is a device that can manufacture solder ball carriers. In this apparatus, in order to reliably press the solder into the through hole of the sheet, it is effective to install the rotating roll 5A in the molten solder bath.

The operation of another embodiment of the present invention will be described with reference to FIG.

Right and left symmetrical structures 9 are placed directly above the solder bath surface of the molten solder bath 3. Each of the structures 9 has a structure in which the tip can shape the solder 2 to the thickness of the sheet 1, and has a water flow path therein to cool and solidify the solder. Further, an ultrasonic oscillation horn is arranged in the molten solder bath so as to face the through hole surface of the sheet 1.

Sheet 1 with through holes in molten solder bath
Is immersed in the space between the respective structures 9, and electric power is supplied to the ultrasonic horn 21 so that the ultrasonic horn is
The 21 vibration waves propagate through the molten solder to eliminate air in the through-hole and allow the solder to enter. Then, the sheet 1 is pulled up as indicated by an arrow A. In this case, the sheet 2 is sandwiched between the structures 9 and the sheet 1 is pulled up while applying a constant pressure, so that the solder 2 entering the through-hole of the sheet 1 is shaped at the tip of the structure 9 and cooled and solidified inside. This is an apparatus that can manufacture a solder ball carrier.

FIG. 14 shows another embodiment of the present invention, and its operation will be described.

To the extent that the solder does not melt on the sheet 1 having through holes, for example, Sn-40% Pb solder (melting point: 183 to 190 ° C.)
When press-fitting, the sheet 1 is placed on the preheating plate 3A preheated to 170 ° C. or less, and the feeding jig 13 is
The molten solder 2 is moved while being dropped into the through hole and supplied to the entire area. Following the movement of the molten solder supply jig 13, the molten solder 2 is moved by pressing the molten solder 2 into the through hole by the high-temperature rotating roll 5. In addition, the tip has a shaping function part at the tip so that the solder in the through-hole that has been pressed in so as to follow the roll 5 so that the solder does not flow out, and the solder other than the through-hole can be removed. A method and an apparatus for manufacturing a solder ball carrier by providing a path 11 and moving a structure 9 for cooling and solidifying the solder 2.

Another embodiment of the present invention will be supplementarily described with reference to FIGS.

FIG. 12 is a vertical sectional view of a through hole obtained by press-fitting and cooling and solidifying the solder 2A into the through hole of the sheet 1, and the through hole of the sheet 1 has a longitudinal sectional area 15 at one open end and an open end at the other. This is formed so as to be larger than the vertical cross-sectional area 16 at the end, and facilitates press-fitting of the solder 2A.

FIG. 13 shows a vertical cross-sectional shape of the through hole of the sheet 1 made of an asymmetric trapezoid (17 and 18). The press-fitted solder 2A is re-melted into a solder ball and supplied to other parts. In this case, the solder is moved in one direction, that is, the one having a larger volume due to the surface tension of the molten metal, and the effect that the solder balls are positioned as high as possible above the sheet surface to facilitate supply is considered.

〔The invention's effect〕

According to the present invention, in a method and an apparatus for manufacturing a solder ball carrier, an inexpensive solder ball capable of supplying a small amount of solder with high accuracy by press-fitting a solder into a through hole of a sheet, shaping, and cooling and solidifying the solder. Carriers can be mass-produced, and by supplying them to the semiconductor mounting portion, there is an effect that a semiconductor device having an inexpensive and highly reliable solder joint can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of the sheet of the present invention, and FIG.
FIG. 3 is a cross-sectional view taken along the line II-II in FIG. 1, FIG. 3 is a cross-sectional view showing a state where solder is pressed into FIG. 2, and FIG. 4 is a vertical cross-sectional view of a manufacturing apparatus showing one embodiment of the present invention. FIGS. 5 to 9 are views for explaining a manufacturing process of an embodiment of the present invention, FIGS. 10 to 14 are cross-sectional views showing another embodiment of the present invention, and FIG. FIG. DESCRIPTION OF SYMBOLS 1 ... Sheet, 1A ... Through hole, 2 ... Solder, 2A ... Press-fit solder, 3 ... Molten solder bath, 5 ... Rotating roll, 7 ... Elevating mechanism, 9 ... Structure.

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Ichiji Yamada 4026 Kuji-cho, Hitachi City, Ibaraki Prefecture Within Hitachi Research Laboratory, Hitachi, Ltd. (56) References JP-A-1-308038

Claims (10)

(57) [Claims] 1. A through hole is formed in a sheet which does not react with the solder by melting, and the sheet is immersed in a molten solder bath, and the solder is pressed into the through hole, and the pressed solder is shaped, cooled and solidified. A method for producing a solder ball carrier. 2. A lift mechanism for raising and lowering a sheet into a molten solder bath, a plurality of rotating rolls for pressing the solder into through holes of the sheet, and a structure for shaping, cooling and solidifying the press-fit solder. An apparatus for manufacturing a solder ball carrier. 3. The apparatus for manufacturing a solder ball carrier according to claim 2, wherein the rotating roll is provided in or on a bath of the solder in the molten solder bath. 4. The structure comprises: a shaping section provided adjacent to a rotating roll and shaping press-fit solder pressed into a through hole of a sheet; and a cooling section cooling and solidifying the press-fit solder after shaping. 3. The apparatus for manufacturing a solder ball carrier according to claim 2, wherein: 5. The solder ball carrier manufacturing apparatus according to claim 2, further comprising a control mechanism for interlocking the operation of the rotating roll and the structure with an operation signal of the lifting mechanism. 6. The apparatus for manufacturing a solder ball carrier according to claim 2, wherein the rotating roll is formed of ceramics. 7. An apparatus for manufacturing a solder ball carrier according to claim 2, wherein the rotating roll is formed by coating a metal material having a low melting reaction with solder on the surface thereof. 8. A manufacturing apparatus for a solder ball carrier, comprising a through-hole having a vertical cross-sectional shape formed in a shape in which two trapezoids or semi-circles of different shapes are arranged such that the upper sides thereof are in contact with each other. Sheet. 9. A sheet having a through hole is placed on a preheating plate, and solder dripped from one surface of the sheet is pressed into the through hole by moving a rotating roll, and the solder is pressed into the through hole so as to follow the rotating roll. A method for producing a solder ball carrier, comprising shaping, cooling, and solidifying. 10. A preheating plate on which a sheet is placed, a supply jig that moves while dripping solder from one surface of the sheet, and at least one rotating roll that moves while pressing the solder into the sheet. A solder ball carrier manufacturing apparatus comprising: a structure that moves following the rotating roll to shape the press-fit solder, and to cool and solidify the solder.