JPH09298266A - Removal of solder whisker or solder ball of ic package and removing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of steps in removal of solder whiskers or solder scums and also to prevent deformation of lead in its removing works. SOLUTION: In the method for eliminating solder whiskers and/or solder scums of a lead part 1 led out from a molded part 3a of an IC package 3 generated during manufacturing; solder plating material and solder whiskers/scums attached on the lead part 1 of the IC package 3 is melted by heating the lead part 1 to cause the surface tension based on solder property to flatten the solder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing solder whiskers / scraps in an IC package, which removes solder whiskers / scraps generated in a manufacturing process on a lead portion of an IC package.

[0002]

2. Description of the Related Art Generally, IC packages are classified into an insertion mounting type package and a surface mounting type package. The former is a structure in which a lead pin is inserted into a through hole provided in a printed circuit board for soldering, and the latter is a structure. It has a planar structure that is directly solder-mounted on a soldering pattern (mount pad) provided on a printed circuit board.

A solder plating method is often used as a lead treatment at the time of this mounting, and this is performed for the purpose of performing good soldering mounting and preventing corrosion of the lead portion. The process before and after the solder plating process of the IC package will be explained here. In the molding process, a plurality of resin-sealed mold frames (for example, 6 to 10 stations) are loaded in the rack in the plating process, and the solder plating process is performed. To be done. Next, the model name etc. is stamped on the mold surface (stamping process) and sent to the lead processing step, where primary lead processing (corner cut / resin cut / tie bar removal) and secondary lead processing (lead cut / lead bending) are performed. To be done. This lead processing machine uses a die (punch and die), a fixed bending die method for lead bending, and a roller bending method.

The thus completed IC package separated (cut and bent) one by one is then sent to a characteristic selection step for conducting an electrical characteristic test. This sorting device is generally called a handler device, and each IC package is brought into contact with a test socket one by one, and a tester device connected to the socket determines whether the IC package is a good product or a defective product.

[0005]

However, in the above-described manufacturing process, as a problem of the lead portion of the IC package, a factor due to the variation of the film thickness in the solder plating process, and the bending by the punch and the die in the lead processing. Factors due to abrasion due to wear of the punch and die during processing, or influence of solder that adheres to the punch and die, etc.-Position misalignment at the time of contact with the lead part and measurement socket in the characteristic selection process, and measurement socket The lead part is rubbed or scraped due to wear (damage), etc.
Solder whiskers and dust are generated on the package leads. FIG. 7 is a perspective view showing a lead portion in which the solder whiskers and dust are generated. In the figure, 1 is a lead portion, and a bent portion 1a.
Front and back, mounting surface 1b, mounting surface 1c, mounting portion side 1
Solder beard / dust 2 is generated at various places such as d.

When the IC package in which the solder whiskers and dust are generated is mounted on a printed circuit board, there is a problem that a short circuit (short circuit) accident occurs due to the solder whiskers and dust between the leads. Further, there is a problem that the removal of the solder beard / scrap requires a lot of man-hours depending on the operator, and a lead deformation is newly generated in the removal work.

In view of the above problems, the present invention provides a method and a structure for removing solder whiskers / dust without resorting to the hand of an operator to reduce the number of steps for removing the solder whiskers / dust. It is an object of the present invention to prevent a short circuit accident due to solder whiskers and dust and to provide an IC package with high operation reliability. Further, it is an object of the present invention to obtain a method and a structure for removing solder whiskers / scraps by a method that does not apply a load to the leads, prevent deformation of the leads in the removing work, and improve yield and quality.

[0008]

In order to achieve the above object, the first invention is to remove the solder whiskers and dusts by heat treatment which does not contact the leads. That is, in the first aspect of the present invention, in the method for removing solder whiskers / scraps of an IC package, which removes the solder whiskers / scraps generated in the manufacturing process in the lead portion led out from the mold portion of the IC package, heating the lead portion. Is characterized in that the solder plating and the solder whiskers and scraps applied to the surface of the lead portion are melted and flattened by the surface tension based on the solder characteristics.

At this time, it is preferable that only the lead portion is covered in a tunnel shape, and the inside of the covered portion is heated by a plurality of heat sources. Further, it is preferable that a plurality of pipe heaters are used as a heat source for heating, the temperature is controlled by the temperature control means, and a slight air flow is generated from the inlet to the outlet.

The method according to the first aspect of the present invention is a device for removing solder whiskers / scraps from an IC package, which removes solder whiskers / scraps generated in a manufacturing process on a lead portion derived from a mold portion of the IC package. I
A supply mechanism for supplying the C package, an endless conveyor belt, a first pick-and-press mechanism for adsorbing the IC packages one by one from the supply mechanism and mounting the IC package on the conveyor belt, and the conveyor. A heat generation part that covers only the lead part provided in the substantially middle part of the belt, a storage mechanism that is mounted in a tray for storing the IC package that has been removed at the latter stage of the heat generation part, and the heat generation part of the heat generation part. This can be carried out by an apparatus provided with a second pick-and-press mechanism which is located at the latter stage and which picks up the IC packages, which have been removed on the conveyor belt, and mounts them one by one on the tray of the storage mechanism.

In the second aspect of the invention, the solder whiskers and debris are brushed and removed fully automatically by a brush.
That is, a second aspect of the present invention is a method for removing solder whiskers / scraps generated in a manufacturing process on a lead portion led out from a mold portion of an IC package, wherein the lead brush is provided with a rotating brush. The feature is that the contact drive is performed to remove the solder whiskers and scraps.

At this time, it is advisable to place and position the mold portion of the IC package in the recessed groove, and drive the rotary brush in contact with the lead portion while the lead portion is substantially half-fitted in the recessed groove. In addition, the IC package is alternately positioned on the front and back sides of a mounting positioning block having two recessed grooves to be mounted on each of the front and back sides of the IC package.
It is advisable to drive the rotating brushes on the front and back sides of the lead portion.

The method according to the second aspect of the present invention is a device for removing solder whiskers / scraps in an IC package, which removes solder whiskers / scraps generated in a manufacturing process on a lead portion led out from a mold portion of an IC package, and stored in a tray. I
A supply mechanism for supplying a C package, a concave groove for mounting and positioning the mold part of the IC package, and a plurality of concave grooves into which a plurality of leads are fitted. Placement positioning block, fixing mechanism for fixing the IC package to each of the frontside placement placement positioning block and the backside placement placement positioning block, a rotary brush that abuts and drives a plurality of lead portions, and a removal process According to the process of
This can be carried out by an apparatus provided with a plurality of pick-and-press mechanisms for adsorbing and rotating the packages and moving them up and down, left and right, and a storage mechanism for mounting and storing the IC packages that have undergone the removal processing on a tray.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. First, FIG. 3 is a perspective view showing an example of an IC package. This IC package 3 is a type in which the lead portion 1 is taken out in four directions from the mold portion 3a.
This is called FP (Quad Flat Package).

First, an embodiment of the first invention will be described. FIG. 1 is a perspective view showing an outline of an embodiment of a first invention of the present invention, and FIG. 2 is a sectional view of an essential part of the embodiment.
In the figure, reference numeral 4 denotes an IC package supply unit as a supply mechanism for supplying the IC packages mounted on the tray 5, and the IC package supply unit 4 arranges the trays 5 accommodating a plurality of IC packages 3 in a plurality of stages. Elevation mechanism that stacks and moves up and down, tray cutting mechanism that sends trays 5 to the transport unit one by one, and cut tray 5
A loader unit 6 having a means for sequentially shifting the load to the IC package row, and an empty tray 5 sent out from the loader unit 6 by the same mechanism as the loader unit 6 are sequentially stacked and stored. It comprises a loader section 7.

Reference numeral 8 is a first for sequentially picking up the IC packages 3 one by one from a tray 5 cut out in the loader section 6 of the IC package supply section 4 and carrying and placing them in a predetermined position.
It is the pick and press mechanism of. Reference numeral 9 denotes an endless conveyor belt which mounts and positions the mold portion 3a of the IC package 3 adsorbed by the first pick and press mechanism 8 and rotates.

Reference numeral 10 denotes a heat generating portion provided at a substantially middle portion of the conveyor belt 9 and covers so as to sandwich only the lead portion 1 led out from the mold portion 3a of the IC package 3.
Further, although not shown, an IC package storage unit (L / UL) serving as a storage mechanism for storing the IC package 3 that has been removed by the same mechanism as the IC package supply unit 4 is provided at the subsequent stage of the heat generation unit 10. ) And a second pick-and-press mechanism for adsorbing the IC packages 3 on the conveyor belt 9 and mounting them one by one on the tray 5 of the IC package storage section.

In FIG. 2, 3 is an IC package, 3a is a mold part of the IC package 3, and 1 is a lead part led out from the mold part 3a. Reference numeral 11 denotes a placement / positioning portion installed on the conveyor belt 9, 10 denotes a heat generating portion for covering the lead portion 3a in a tunnel shape, and 12 denotes a pipe heater disposed inside the heat generating portion 10 as a heat source for heating. The temperature near the leads is set to 400 ° C. by a plurality of temperature control means.
It can be variably set to ~ 500 ° C. Further, although not shown, a slight air flow is generated from the inlet of the heat generation part 10 toward the outlet to bring it into a warm air state.

Although only one side of the IC package 3 is shown in FIG. 2, the heat generating portion 10 is constructed so as to straddle both sides. Hereinafter, the operation of the present embodiment will be described. The trays 5 pulled out from the loader unit 6 of the IC package supply unit 4 are 1 in the row in the lateral direction of the tray outer dimensions.
The sheets are sequentially picked up by the first pick-and-press mechanism 8 and conveyed and placed on the conveyor belt 9. The first pick-and-press mechanism 8 is configured to move in pitch with respect to, for example, five IC package pitches accommodated in the lateral direction, and the trays 5 are sequentially arranged in the next row in the longitudinal direction. The pitch is fed. The tray 5 that has been emptied by sequentially removing the IC packages 3 in this manner is stored in the unloader unit 7.

As shown in FIG. 2, the conveyor belt 9 is engraved with a plurality of mounting positioning portions 11 so that the IC packages 3 can be positioned and mounted by fitting the molding portions 3a one by one. The conveyor belt 9 is configured to rotate endlessly as described above, and is configured to rotate or stop in synchronization with the first pick and press mechanism 8.

The IC package 3 mounted on the placement and positioning unit 11 on the transport belt 9 is transported to the heat generation unit 10. In the heat generator 10, the temperature near the reed is set to, for example, 400 to 500 ° C. by the pipe heater 12, the temperature control means, and the warm air as described above, so the reed 1 should pass through such a state. As a result, the solder scraps and whiskers attached and formed on the lead portion 1 are melted and flattened by the surface tension based on the solder characteristics due to the heat.

The IC package 3 after the removal processing is
Subsequently, the second belt (not shown) is carried out from the heat generation section 10 while being mounted on the placement positioning section 11 on the conveyor belt 9.
The pick-and-press mechanism sucks the IC package 3 and conveys and mounts it on an empty tray of an IC package storage unit (not shown), and the IC package storage unit stores the tray together.

The operation has been described for the Gull-Wing type in which the IC package 3 takes out the lead portion 1 in two directions from the main body, but the QFP type has leads in four directions shown in FIG. With regard to (2), a third pick-and-press mechanism for rotating the IC package by 90 ° on the conveyor belt 9 after passing through the heat-generating part 10 and a second heat-generating part are provided to deal with.

Next, an embodiment of the second invention will be described. FIG. 4 and FIG. 5 are cross-sectional views of essential parts showing an embodiment of a second invention of the present invention. FIG. 6 is a schematic view showing the same embodiment, and shows the rotation / placement operation of the IC package 3 step by step. In the figure, reference numeral 13 is a front surface mounting placement positioning block, and 14 is a back surface mounting placement positioning block.
And the backside placement positioning block 14 are respectively I
The recessed grooves 13a and 14a for mounting and positioning the mold portion 3a of the C package 3 and the recessed grooves 13b and 14b into which the lead portions 1 are fitted are provided. The recessed grooves 13b and 14b into which the lead portion 1 is fitted match the bending shapes of the plurality of lead portions 1, and approximately half the thickness of the lead portion 1 is fitted.

Numerals 15 and 16 are fixing blocks as a fixing mechanism for fixing the IC package 3 to each of the front surface mounting placement positioning block 13 and the back surface mounting placement positioning block 14, and 17 is applied to a plurality of lead portions. It is a rotating brush that is driven in contact, and the rotating brush 17 is provided on opposite sides (both sides). This embodiment is further capable of operating vertically and horizontally and rotating with an IC package supply section and an IC package storage section (not shown) similar to those of the above-described first embodiment of the invention, and supplies the IC package. 90 ° by picking up one IC package 3 from each tray 5
The rotating first pick-and-press mechanism 18, and the first
Second pick-and-press mechanism 19 which receives the IC package 3 from the pick-and-press mechanism 18 and rotates 90 ° and reverses direction, and receives the IC package 3 from the second pick-and-press mechanism 19 and rotates 90 °. And a third pick-and-press mechanism 20 for delivering the IC package 3 to the tray 21 of the IC package storage section.

The operation of this embodiment will be described below with reference to FIG. First, the IC package 3 shown in FIG. 3 is adsorbed by the first pick-and-press mechanism 18 from the tray 5 pulled out to the loader section by the IC package supply mechanism (not shown), adsorbed as shown in the figure, and rotated 90 ° ( Figure 5). After that, the second pick and press mechanism 1
9 adsorbs the back surface of the IC package 3 as shown. Therefore, the vacuum of the first pick-and-press mechanism 18 is cut off and the IC package 3 is delivered to the second pick-and-press mechanism 19. Then, by rotating 90 ° similarly to the first pick-and-press mechanism 18, the IC package 3 is inverted and lowered and placed on the backside placement positioning block 14 provided in the lower portion. Next, the fixed block 15 moves to the upper surface of the placed IC package 3 and presses the IC package 3. Then rotating brush 1
7 slides on the upper surface of the lead portion 1 along the lead bending shape, so that the solder whiskers formed on the lead portion 1
Remove scraps. After processing one pair of opposite sides as described above, the entire backside placement positioning block 14 is set to 9
The unprocessed opposite side is processed by rotating it by 0 °, and the back side placement positioning block 14 is rotated again to return to the original state. After the predetermined brushing is completed in this way, the rotary brush 17 moves, and again the second pick-and-press mechanism 19 sucks and raises the IC package 3.
It rotates 90 ° in the direction opposite to the receiving direction (Fig. 5).

After that, the third pick-and-press mechanism 2
0 adsorbs the IC package surface as shown. Therefore, the vacuum of the second pick-and-press mechanism 19 is cut off and transferred to the third pick-and-press mechanism 20. Next, as with the second pick and press mechanism 19, 9
By rotating 0 °, the IC package 3 is inverted,
It is in the same direction as when it was put in, and is lowered and mounted on the surface-mounting positioning block 13 provided at the bottom. Similarly, after that, the rotating brush 1 is fixed by the fixed block 16.
Remove solder beard and scrap by 7. Then, the IC package 3 is sucked and raised again by the third pick and press mechanism 20 (FIG. 5).

Finally, the third IC package 3 is attached.
The pick and press mechanism 20 is moved to the storage side, mounted on the tray 21 (FIG. 5), and stored in the IC package storage unit (not shown).

[0029]

As described above, according to the first aspect of the present invention, the solder whiskers and scraps of the IC package are removed, which removes the solder whiskers and scraps generated in the manufacturing process in the lead portion led out from the mold portion of the IC package. In the removal method, by heating the lead portion, the solder plating and the solder whiskers and scraps applied to the surface of the lead portion are melted and flattened by the surface tension based on the solder characteristics, so that heat treatment that does not contact the leads Can remove solder whiskers and dust.

As a result, it becomes possible to remove solder whiskers and debris without the need for the operator's hand, and the man-hour for removing the solder whiskers and debris can be reduced to zero.
There is an effect of preventing a short circuit accident due to dust and providing an IC package with high operation reliability. Furthermore, according to the first aspect of the present invention, since the processing is performed without contacting the lead portion, it is possible to remove the solder whiskers / scraps without applying a load. Therefore, there is an effect that the lead deformation in the removing work is prevented and the yield and quality are improved.

At this time, only the lead portion is covered in a tunnel shape, and inside the covered portion is heated by a plurality of heat sources, and a plurality of pipe heaters are used as a heat source for heating, and the temperature is controlled by a temperature control means and is turned on. When a warm air condition is generated in which a slight breeze is generated from the mouth to the exit, there is an effect that a stable treatment effect can be controlled.

According to the second aspect of the present invention having the above structure, the solder whiskers and scraps of the IC package are removed, which removes the solder whiskers and scraps generated in the manufacturing process on the lead portion led out from the mold portion of the IC package. In the removing method, the rotating brush is brought into contact with and driven by the lead portion to remove the solder whiskers and scraps, so that the solder whiskers and dust can be brushed and removed fully automatically by the brush.

As a result, as in the first aspect of the invention, it becomes possible to remove the solder whiskers and dust without the operator's hand, and the man-hour for removing the solder whiskers and dust can be made zero, and the solder whiskers and dust can be eliminated. -It has the effect of preventing a short circuit accident due to dust and providing an IC package with high operational reliability. At this time, when the mold portion of the IC package is placed and positioned in the concave groove and the lead portion is fitted in the concave groove approximately halfway and the rotary brush is driven to contact the lead portion, the load of the rotary brush is reduced. On the other hand, since the lead portion can be protected, there is an effect that the lead deformation in the removing work is prevented and the yield and quality are improved.

Further, the IC packages are alternately positioned on the mounting positioning blocks having two concave grooves to be mounted on the front and back sides of the IC package, and the rotating brushes are respectively mounted on the front and back sides of the lead portion. The contact drive has an effect that the solder whiskers and scraps formed on the front and back surfaces and the sides of the leads can be reliably removed.

[Brief description of drawings]

FIG. 1 is a perspective view showing an outline of an embodiment of a first invention of the present invention.

FIG. 2 is a cross-sectional view of essential parts of an embodiment of a first invention of the present invention.

FIG. 3 is a perspective view showing an example of an IC package.

FIG. 4 is a cross-sectional view of essential parts showing an embodiment of a second invention of the present invention.

FIG. 5 is a cross-sectional view of essential parts showing an embodiment of a second invention of the present invention.

FIG. 6 is a schematic view showing an embodiment of a second invention of the present invention.

FIG. 7 is a perspective view showing a lead portion in which solder whiskers and dust are generated.

[Explanation of symbols]

 1 Lead Section 3 IC Package 4 IC Package Supply Section 5 Tray 6 Loader Section 7 Unloader Section 8 First Pick and Press Mechanism 9 Conveyor Belt 10 Heat Generation Section 12 Pipe Heater 13 Positioning Block for Surface Mounting 14 Backside Mounting Placement positioning block 15, 16 Fixed block 17 Rotating brush 18 First pick and press mechanism 19 Second pick and press mechanism 20 Third pick and press mechanism 21 Tray

Claims (8)

[Claims] 1. A method for removing solder whiskers / scraps in an IC package, which removes solder whiskers / scraps generated in a manufacturing process on a lead part led out from a mold part of an IC package, by heating the lead part, Melt the solder plating and solder whiskers and scraps on the surface of the lead part,
A method for removing solder whiskers / scraps of an IC package, which comprises flattening by surface tension based on solder characteristics. 2. The method for removing solder whiskers / scraps of an IC package according to claim 1, wherein only the lead portion is covered in a tunnel shape, and the inside of the covered portion is heated by a plurality of heat sources. 3. A warm air state in which a plurality of pipe heaters are used as a heat source for heating, the temperature is controlled by a temperature control means, and a slight breeze is generated from an inlet to an outlet. Item 2. A method for removing solder whiskers and scraps from an IC package according to Item 2. 4. An IC package solder whiskers / scraps removing device for removing solder whiskers / scraps generated in a manufacturing process from a lead portion led out from a mold portion of the IC package, and supplying the IC package mounted on a tray. A mechanism, an endless conveyor belt, a first pick-and-press mechanism for adsorbing the IC packages one by one from the supply mechanism and mounting the IC package on the conveyor belt, and an intermediate portion of the conveyor belt. A heat generating section that covers only the provided lead section, a storage mechanism that is in the latter stage of the heat generating section and that stores the IC package that has been subjected to the removal processing in a tray, and a transport belt that is in the latter stage of the heat generating section. A second pick-and-press mechanism that adsorbs the IC packages that have undergone the above removal processing and mounts them one by one on the tray of the storage mechanism; An IC package solder whiskers / scraps removing apparatus comprising: 5. A method for removing solder whiskers / scraps generated in a manufacturing process on a lead part led out from a mold part of an IC package, wherein a rotating brush is brought into contact with the lead part. And then, Handa Beard
A method for removing solder whiskers and scraps from an IC package, which is characterized by scraping off scraps. 6. The rotating brush is brought into contact with and driven by the lead portion in a state where the mold portion of the IC package is placed and positioned in the recessed groove and the lead portion is substantially half-fitted in the recessed groove. The method for removing solder whiskers / scraps of an IC package according to claim 5. 7. The IC package is alternately positioned on the front and back of a mounting positioning block provided with two concave grooves to be mounted on each of the front and back of the IC package, and a rotating brush is attached to each of the front and back of the lead portion. 6. The method for removing solder whiskers / scraps of an IC package according to claim 5, wherein the method is abutting drive. 8. An IC package solder whiskers / scraps removing device for removing solder whiskers / scraps generated in a manufacturing process from a lead portion led out from a mold portion of the IC package, and supplying the IC package accommodated in a tray. A mechanism, a recessed groove for mounting and positioning the mold part of the IC package and a recessed groove into which a plurality of leads fit, and a mounting positioning block for front surface mounting and a mounting positioning block for rear surface mounting, A fixing mechanism for fixing the IC package to each of the mounting positioning block for front surface mounting and the mounting positioning block for back surface mounting, a rotary brush that abuts and drives a plurality of lead portions, and the removal processing is sequentially performed according to the removal process. A plurality of pick-and-press mechanisms for adsorbing the IC package, rotating it, and moving it vertically and horizontally; And a storage mechanism for storing the processed IC package on a tray.
C package solder beard / scrap remover.