JP2927777B1 - Method and apparatus for cleaning a fine component of a work - Google Patents

Abstract

[Problem] An object to be cleaned is an FC / BGA type LSI
A technology that can precisely clean a workpiece that is between two narrow planes in a short time. SOLUTION: A cleaning liquid 8 penetrates into a fine component 6 in which fine solder balls 7 are interposed between two planes formed by an integrated circuit chip 4 and a substrate 5, and a gap edge 15 between the two planes. High-speed flow 9a, 9b, 10
a and 10b are formed to clean the inside between the two planes by sucking the cleaning liquid 8 that has permeated the fine structure portion 6. After the cleaning between the two planes, the gap edge 15 between the two planes is further cleaned. A high-speed flow of drying air may be formed along the line to dry the inside between the two planes.

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus suitable for cleaning a fine component of a work, and more particularly to a solder ball in which an integrated circuit chip (wafer) is mounted on a substrate via a fine solder ball. The present invention belongs to a method suitable for cleaning a fine component such as a welded portion and a cleaning apparatus used for the method.

[0002]

2. Description of the Related Art Conventionally, in the case where the inside of a fine component of a work is to be precisely cleaned, an ultrasonic wave is generated in a cleaning liquid in which the work is immersed, and the characteristics of the ultrasonic wave are used to generate a fine wave. A method of dissolving unnecessary substances fixed or covered between various components in a cleaning liquid or removing them by vibration separation is adopted. In such a cleaning method, a portion where ultrasonic waves are well irradiated in the cleaning liquid can be precisely cleaned.

[0003]

In a work in which the fine components to be cleaned are shielded on both sides, for example, a flip-chip ball grid array (FC / BGA) type LSI which is currently under active development is integrated. A circuit chip is mounted on the substrate by welding a large number of solder balls (for example, 900) arranged on the entire back surface of the integrated circuit chip to the substrate. There is only a gap of about 0.05 mm between the integrated circuit chip having such a configuration and the substrate. When the solder balls are welded to the substrate, a flux is used.However, since this flux is in a state of being attached between the fine solder balls, the flux must be removed and cleaned before resin molding. Must. However, in the cleaning method using the ultrasonic waves, since the flux exists between the semiconductor chip and the substrate and the gap is narrow, the ultrasonic waves cannot be radiated well to the inside, and the flux is completely removed. It takes several hours to remove, so FC / BGA type L
There is a problem that the industrialization of SI is alienated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem. It is an object of the present invention to provide a method in which an object to be cleaned is located between two narrow planes as in the FC / BGA type LSI. An object of the present invention is to provide a method capable of precisely cleaning even such a work in a short time and a cleaning apparatus used for the method.

[0005]

Means for Solving the Problems (Solution 1) In order to achieve the above object, in the method for cleaning a finely structured portion of a work according to claim 1 of the present invention, a fine structure provided between two narrow flat surfaces. A method of cleaning a part, wherein a cleaning liquid is permeated into the fine component and a high-speed flow of the cleaning liquid is formed along the edge of a gap between the two planes to permeate the fine component. It is characterized in that the inside between the two planes is cleaned by sucking the cleaning liquid.

According to a second aspect of the present invention, there is provided a method of cleaning a finely configured portion of a work, wherein the finely configured portion provided between two narrow planes is cleaned. After cleaning the inside between the two planes by infiltrating the cleaning liquid into the part and forming a high-speed flow of the cleaning liquid along the edge of the gap between the two planes to suck the cleaning liquid that has permeated the fine component parts A high-speed flow of drying air is formed along the edge of the gap between the two planes to dry the interior between the two planes.

According to a third aspect of the present invention, there is provided a method for cleaning a finely structured portion of a work, wherein the two planes are integrated circuits. The semiconductor device is characterized in that it is formed of a chip and a substrate, and the fine component is a fine solder ball for conducting a circuit of the integrated circuit chip to a substrate contact.

According to a fourth aspect of the present invention, there is provided an apparatus for cleaning a finely configured part of a work, wherein the apparatus for cleaning a finely configured part of a work according to any one of the first to third aspects is used. And a nozzle for forming a high-speed flow of the cleaning liquid along the edge of the gap between the two planes of the work fixed at a predetermined position.

According to a fifth aspect of the present invention, there is provided an apparatus for cleaning a finely structured part of a work, wherein the two planes of the work are an integrated circuit chip, a substrate and And a rectifying plate having a surface portion appropriately wider than the integrated circuit chip and forming a gap between the integrated circuit chip and the substrate while covering the integrated circuit chip.

According to a sixth aspect of the present invention, in the apparatus for cleaning a fine component of a work according to the fifth aspect, the nozzle is provided with a pair of opposing surfaces of the integrated circuit chip. In addition to disposing the cleaning liquid one by one toward the corners, the cleaning liquid is discharged toward the gaps of the corners, and provided so as to form a high-speed flow of the cleaning liquid along the edges of the gaps spreading from the corners. I do.

According to a seventh aspect of the present invention, in the apparatus for cleaning a fine component of a work according to any one of claims 4 to 6, A nozzle for forming a high-speed flow of drying air is provided along an edge of a gap between two planes of the work.

[0012]

According to the first aspect of the present invention, when a high-speed flow of the cleaning liquid is formed along the edge of the gap between the two planes so that a part of the cleaning liquid permeates into the fine components of the work, the cleaning liquid comes into contact with the high-speed flow. Since the gap edge side becomes negative pressure and the inner surface side of the two planes is suctioned in that direction, the cleaning liquid that has permeated in the fine components in the two planes generates a flow rate and adheres to the fine part gap. Unnecessary substances such as fine powders, fats and oils and fluxes are easily eluted, and the cleaning liquid eluted from the unnecessary substances is sucked into a high-speed flow and discharged out of two planes, and finally, the fine component parts are cleaned. . Since the high-speed flow of the cleaning liquid does not directly act on the fine components, the cleaning can be performed without deforming the fine components. Since the cleaning liquid flows in the fine components, the elution of unnecessary substances is facilitated, and the cleaning liquid is positively discharged at a high flow rate, so that the cleaning can be efficiently performed by a simple operation.

According to the second aspect of the present invention, after the cleaning of the fine components, the cleaning air sucked in the air between the two flat surfaces is sucked by the same operation as the cleaning, and the cleaning air is discharged to the outside. Essential components can be dried efficiently. It is economical because a large amount of drying air is not required and a drying air supply device can be downsized.

According to the third aspect of the present invention, since the integrated circuit chip is very small, the solder balls interposed between the integrated circuit chip and the substrate are very small. The flux adhering between the solder balls elutes into the washing solution, and the washing solution with the eluted flux is sucked by the high-speed flow and discharged out of two planes, so that the arrangement portion of the fine solder balls can be efficiently washed. .

According to the fourth aspect of the present invention, a high-speed flow of the cleaning liquid is formed along the edge of the gap between the two planes by the nozzle so that a part of the cleaning liquid permeates into the fine components of the work. Since the edge side of the gap in contact with the high-speed flow becomes negative pressure and the inner surface side of the two planes is suctioned in that direction, a fine component in the two planes generates a flow rate in the permeating cleaning liquid, causing Fine powder,
Unnecessary substances such as fats and oils and flux are eluted, and the cleaning liquid in which the unnecessary substances are eluted is sucked into a high-speed flow and discharged out of two planes, whereby a fine component can be washed. The structure of the device can be easily provided,
Position adjustment and the like can be performed with a simple structure. It is economical because a large amount of cleaning liquid is not required and a cleaning liquid supply device and a waste liquid treatment device can be downsized.

According to the fifth aspect of the present invention, when the area of the integrated circuit chip is smaller than the area of the substrate, the integrated circuit chip can be formed even when a high-speed flow of the cleaning liquid is formed along the edge of the gap between the integrated circuit chip and the substrate. The high-speed flow does not concentrate along the edge of the gap due to the open side, but since the integrated circuit chip is covered with the rectifying plate, the high-speed flow of the cleaning liquid can be restrained between the rectifying plate and the substrate. A high-speed flow is formed intensively along the edge of the gap, and can be washed and cleaned well.

In the invention according to claim 6, by aiming at the corner of the integrated circuit chip with the high-speed flow formed by the nozzle, the high-speed flow is separated from the corner to both sides of the integrated circuit chip, and a part of the high-speed flow is from inside the gap. It is possible to efficiently purify the flux by infiltrating into the fine component to promote the elution of the flux, and simultaneously performing the elution, washing, and discharging. By simultaneously aiming at the diagonals of the integrated circuit chip, the impact forces act so as to cancel each other out, so that a simple fixing method can be adopted, and precision cleaning is performed by such a simple fixing method. be able to.

In the invention according to the seventh aspect, by performing drying after the washing, it is possible to efficiently perform a better and more complete cleaning.

[0019]

Embodiments of the present invention will be described below in detail with reference to the drawings. In the present embodiment, F
The following describes an example of a work in which a C / BGA type LSI integrated circuit chip is mounted on a substrate via fine solder balls. FIG. 1 is an explanatory view showing a cleaning device for a fine component of a work according to the present embodiment, FIG. 2 is an enlarged explanatory view of a main part,
FIG. 3 is an explanatory diagram showing a cleaning state.

FIG. 2 shows the arrangement of the work 1 and the nozzles 2 and 3 at the time of cleaning. Reference numeral 4 denotes an integrated circuit chip of the work 1, 5 denotes a substrate, and 6 denotes a fine space between the integrated circuit chip 4 and the substrate 5. These are fine components in which a large number of solder balls 7 are arranged and welded on a lattice. The nozzles 2 and 3 are used to discharge the cleaning liquid 8 as substantially fan-shaped jets 9 and 10,
The works 1 are arranged so as to face each other on a horizontal straight line, and the work 1 is arranged so that the opposing corners of the integrated circuit chip 4 face the nozzles 2 and 3. A rectangular body 11 indicated by a chain line in the figure is a rectifying plate,
When the workpiece 1 is cleaned, that is, when it is cleaned and dried, it is disposed so as to cover the upper surface of the integrated circuit chip 4 as shown in FIG. In this state, a rectifying path 12 is formed around the integrated circuit chip 4, the rectifying plate 11, and the substrate 5. Reference numeral 13 denotes a flux attached between the solder balls 7 of the fine component 6, and reference numeral 14 denotes a space where the flux is not present or the flux is removed.

Next, the operation of the jets 9 and 10 will be described. The jets 9 and 10 are integrated circuit chips 4
After contact with the corner of the gap 1, as shown in FIG.
5, high-speed flows 9a and 9b and high-speed flows 10a and 10b are formed in the rectification path 12 so as to simultaneously surround the four gap edges 15 of the integrated circuit chip 4. The high-speed flows 9a and 9b and the high-speed flows 10a and 10
When b rapidly flows so as to contact the gap edge 15, the space between the integrated circuit chip 4 and the substrate 5, that is, the fine component 6 side is strongly sucked.

When the jets 9 and 10 come into contact with the corners of the integrated circuit chip 4, a part of the jets becomes a space-free space portion 14 in the fine component 6.
Infiltrate The cleaning liquid 8 that has entered the space portion 14 elutes the flux 13 and at the same time, the high-speed flow 9a,
9b and the high-speed flows 10a and 10b are sucked and flow toward the gap edge 15 side. When the washing liquid 8 flows,
A large number of the solder balls 7 cause turbulence, and as shown in the enlarged portion of FIG. 2, the solder balls 7 are sucked toward the edge of the gap while wrapping around the entire circumference of each solder ball 7, and a new cleaning liquid is caused to enter by this suction. The elution of the flux is promoted, and the flux at any place can be efficiently removed and washed. Further, by simultaneously aiming and shooting the diagonals of the integrated circuit chip 4, the impact forces act so as to cancel each other out, so that a simple fixing method can be adopted. Can be washed.

Next, the process up to the completion of the cleaning of the workpiece will be described with reference to FIG. The work 1 in this example is the work 1
In order to simultaneously clean the entire surface of the substrate, particularly the solder ball welded portion 16 on the rear surface of the substrate, the substrate 5 is disposed with the rear surface facing upward and the integrated circuit chip 4 facing downward. (Overall Cleaning Step) First, the work 1 is carried into the cleaning tank 20 by an arm (not shown). The cleaning tank 20 includes a supply unit 21 for a quasi-aqueous cleaning liquid, a nozzle 22 for overall cleaning, and nozzles 2 and 3 for cleaning fine components. Then, the quasi-aqueous cleaning liquid (for rosin flux) pumped by the cleaning liquid pump of the supply unit 21 is applied to each of the nozzles 22, 2, 2.
3, which is jetted as a jet, and cleans the solder ball welding portion 16 and the fine component portion 6 of the integrated circuit chip by the operation described above.

(First Draining Step) After the entire cleaning step of the work 1 is completed, the work 1 is carried into the first drip tank 23. The first draining tank 23 is provided with a supply section 24 for clean pressure air, a nozzle 25 for overall drying, and nozzles 2a and 3a for drying the fine component. And the supply unit 24
Is jetted from each of the nozzles 25, 2a, 3a as a jet, and the cleaning liquid of the entire surface of the workpiece and the fine component 6 of the integrated circuit chip is removed by the above-described operation.

(Pre-rinsing step) After completion of the drying step,
The work 1 is carried into the pre-rinse tank 26. The pre-rinse tank 26 includes a pre-rinse (pure water) supply section 27, a nozzle 28 for overall pre-rinse, and nozzles 2b and 3b for pre-rinse in the fine component section. And the supply unit 2
The pre-rinse pumped by the pre-rinse pump 8 is jetted from each of the nozzles 28, 2b, 3b as a jet, and the pre-rinsing of the entire workpiece and the fine component 6 of the integrated circuit chip is performed by the operation described above. still,
The supply unit 27 includes a pure water regenerating device, and the pure water is reused in the pure water regenerating device as a closed system.

(Second Draining Step) After the pre-rinsing step of the work 1, the work 1 is carried into the second drip tank 29. The liquid draining tank 29 includes a clean pressure air supply unit 30 similar to that in the first liquid draining step, a nozzle 31 for drying the entirety, and nozzles 2c and 3c for drying the fine components. Then, the clean pressure air of the supply unit 30 is jetted from each of the nozzles 31, 2 c, and 3 c as a jet, and the cleaning liquid is removed from the entire surface of the work and the fine component unit 6 of the integrated circuit chip by the operation described above.

(Finish Rinse Step) After the completion of the second liquid draining step, the work 1 is carried into the finish rinse tank 32. The finishing rinsing tank 32 includes a finishing rinsing (pure water) supply unit 33 similar to that in the pre-rinsing step, a nozzle 34 for overall finishing rinsing, and nozzles 2d and 3d for rinsing fine components. And the supply unit 33
The finishing rinse pumped by the finishing rinsing pump is jetted from each of the nozzles 34, 2d, and 3d as a jet, and the entire work and the fine component 6 of the integrated circuit chip are rinsed by the operation described above. .
The supply unit 33 includes a pure water regenerating device, and the pure water is reused by the pure water regenerating device as a closed system.

(Drying Step) After the finish rinsing step of the work 1, the work 1 is carried into the drying tank 35. The drying tank 35 includes a clean pressure air supply unit 36 having a precision filter (for example, HEPA) and a heater for heating air.
And a nozzle 37 for drying the entire structure and nozzles 2e and 3e for drying the fine component. Then, the clean pressure air of the supply unit 36 is jetted from each of the nozzles 37, 2e, and 3e as a jet, and the entire surface of the work and the fine component 6 of the integrated circuit chip are dried by the above-described operation.

Although the embodiment has been described above, the specific configuration of the present invention is not limited to the embodiment, and even if there is a design change or the like without departing from the gist of the invention. Included in the invention.

The first draining step and the second draining step may be integrated. Further, the pre-rinsing step and the finishing rinsing step may be integrated. Work is FC / BGA type LSI
The present invention is not limited to this, and can be applied to a precision machine such as a timepiece, a micro machine, or the like, which has another fine component.

[0031]

As described above, in the method for cleaning a fine component of a work according to the first aspect of the present invention,
Since the above-described method is employed, the edge of the gap in contact with the high-speed flow becomes a negative pressure, and the inner surface of the two planes is suctioned in that direction. Unnecessary substances such as fine powder, oils and fats, and flux that have adhered to the gaps in the fine parts are easily eluted, and the washing liquid in which the unnecessary substances have eluted is sucked into the high-speed flow and discharged out of two planes. Fine components can be cleaned. Since the high-speed flow of the cleaning liquid does not directly act on the fine components, the cleaning can be performed without deforming the fine components. Since the cleaning liquid flows in the fine components, the elution of the unnecessary substances is facilitated, and the high-speed flow actively discharges the cleaning liquid. can get.

In the method for cleaning a fine component of a workpiece according to the second aspect, since the above method is employed, after cleaning the fine component, the drying air is supplied to the inside of the two planes by the same operation as the cleaning. By suctioning and discharging the cleaning liquid that has stayed at the surface, fine components can be efficiently dried. A large amount of drying air is not required, and the drying air supply device and the like can be reduced in size.

According to the third aspect of the present invention, since the above method is adopted, even if the solder balls interposed between the integrated circuit chip and the substrate are fine, Even the flux used during the welding and adhered between the solder balls elutes in the cleaning solution,
The cleaning solution in which the flux has been eluted is sucked by the high-speed flow and discharged out of the two planes, so that the effect that the arrangement portion of the fine solder balls can be efficiently cleaned can be obtained.

In the apparatus for cleaning a finely structured part of a work according to the fourth aspect of the present invention, since the above configuration is adopted, the edge of the gap in contact with the high-speed flow becomes a negative pressure and the inner surface of the two planes is subjected to a suction action in that direction. Therefore, the flow rate of the cleaning liquid that has permeated in the fine components in these two planes is generated, and unnecessary substances such as fine powder, oil and fat, and flux that have adhered to the gaps in the fine parts are eluted, and the unnecessary substances are eluted. By sucking the cleaning liquid in a high-speed flow and discharging the cleaning liquid out of the two planes, it is possible to clean fine components. The structure of the device can be easily provided, and the position can be adjusted with a simple structure. A large amount of cleaning liquid is not required, and the cleaning liquid supply device and the waste liquid treatment device can be miniaturized.

In the apparatus for cleaning a finely structured part of a work according to the present invention, the integrated circuit chip is covered with a rectifying plate even when the area of the integrated circuit chip is smaller than the area of the substrate. Therefore, the high-speed flow of the cleaning liquid can be restrained between the rectifier plate and the substrate, and the high-speed flow can be formed intensively along the gap edge of the integrated circuit chip, so that the cleaning and cleaning can be performed well. The effect is obtained.

In the apparatus for cleaning a finely structured part of a work according to claim 6, since the above structure is adopted, the high-speed flow formed by the nozzle is aimed at the corner of the integrated circuit chip so that the high-speed flow is reduced from the corner. Divided into both sides of the integrated circuit chip, part of the chip penetrates into the fine components from inside the gap to promote the elution of the flux, and at the same time performs the elution, washing, and discharging, so that the cleaning can be performed efficiently. . Also,
By simultaneously aiming at the diagonals of the integrated circuit chip, the impact forces act to cancel each other out,
It is possible to adopt a simple fixing method, and it is possible to obtain an effect that the cleaning can be accurately performed by such a simple fixing method.

In the apparatus for cleaning a finely structured part of a work according to claim 7, the corners of the integrated circuit chip are shot by the high-speed flow formed by the nozzles. By performing the drying, it is possible to obtain an effect such that the cleaning can be more efficiently performed with a high degree of perfection.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a cleaning device for a fine component of a work according to an embodiment of the present invention.

FIG. 2 is an enlarged explanatory view of a main part of the embodiment.

FIG. 3 is an explanatory diagram showing a cleaning state of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Work 2, 3 Nozzle 4 Integrated circuit chip (two planes) 5 Substrate (two planes) 6 Microstructure part 7 Solder ball 8 Cleaning liquid 9a, 9b High-speed flow 10a, 10b High-speed flow 11 Rectifier plate 15 Gap edge

Claims (7)

(57) [Claims] 1. A method for cleaning a fine component provided between two narrow planes, wherein the cleaning liquid penetrates the fine component and the cleaning liquid extends along an edge of a gap between the two planes. Cleaning the fine component of the workpiece by forming the high-speed flow and sucking the cleaning liquid permeating the fine component to clean the inside between the two planes. 2. A method for cleaning a fine component provided between two narrow planes, wherein the cleaning liquid penetrates the fine component and the cleaning liquid extends along the edge of a gap between the two planes. After cleaning the interior between the two planes by forming the high-speed flow and sucking the cleaning liquid that has permeated the fine component, a high-speed flow of drying air is formed along the gap edge between the two planes. A method for cleaning a fine component of a work, comprising drying the interior between two planes. 3. The semiconductor device according to claim 2, wherein the two planes are formed by an integrated circuit chip and a substrate, and the fine component is a fine solder ball for connecting a circuit of the integrated circuit chip to a substrate contact. 3. The method for cleaning a finely structured part of a work according to claim 1 or 2. 4. An apparatus for use in the method for cleaning a finely structured part of a work according to claim 1, wherein the two planes of the work fixed at a predetermined position are provided. And a nozzle for forming a high-speed flow of the cleaning liquid along the edge of the gap. 5. The work has two planes formed by an integrated circuit chip and a substrate, and has a surface portion appropriately wider than the integrated circuit chip in a state where the work is covered on the integrated circuit chip and a gap between the work and the substrate. 5. The apparatus for cleaning a fine component of a work according to claim 4, further comprising a rectifying plate for forming a work. 6. The nozzles are arranged one by one toward a pair of opposing corners of the integrated circuit chip, and a cleaning liquid is discharged toward a gap between the corners, and the nozzles are disposed between gap edges extending from the corners. 6. The apparatus for cleaning a fine component of a work according to claim 5, wherein the apparatus is provided so as to form a high-speed flow of the cleaning liquid along the same. 7. The apparatus according to claim 4, further comprising a nozzle for forming a high-speed flow of drying air along an edge of a gap between two planes of the work. A cleaning device for a fine component of the work described in the above. [0001]