JPH0823156A - Method for sealing electronic component and surface grinder for grinding sealing resin - Google Patents

Abstract

PURPOSE:To provide a method which allows excellent cost performance, productivity and dimension accuracy for sealing an electronic component. CONSTITUTION:An IC chip 7, which is an electronic component, is mounted on a substrate 1 for mounting electronic component. Sealing resin 26 is printed on the substrate 1 using a metal mask, and whole plane of the IC chip 7 is covered. Then, the printed sealing resin 26 is heat-cured. The top plane of the cured sealing resin 26 is ground by a surface grinder 8, and the sealing resin 26 is permitted to have a prescribed thickness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for sealing electronic parts and a surface grinding machine for grinding a sealing resin.

[0002]

2. Description of the Related Art Conventionally, in the process of manufacturing a semiconductor package in which the total thickness is severely limited, in order to protect electronic components such as IC chips and LSI chips mounted on an electronic component mounting substrate from external moisture. In some cases, resin sealing is performed.

As a method of sealing with resin, for example,
A method (transfer molding method) is known in which a substrate on which an IC chip is mounted is set in a mold and a sealing resin is injected into the mold to mold the resin into a predetermined shape.

There is also known a method (potting method) in which a sealing frame having a certain thickness is provided on a substrate on which an IC chip is mounted and a sealing resin is poured into the frame by a dispenser or the like. Furthermore, a sealing method is also performed in which the sealing thickness is controlled by cutting the upper surface of the resin formed by the potting method without using a sealing frame with a planing machine having a metal cutting blade. ing.

[0005]

However, the above-mentioned transfer molding method has a drawback that the equipment cost is increased because a dedicated mold and a large-sized apparatus for molding are required. .

The potting method has a drawback in that the cost of material for the substrate is high because a sealing frame is required. Further, since the application is performed by a dispenser, the number of sheets that can be processed at one time is small, and the production efficiency is poor.

In the method of cutting after potting, in addition to the poor production efficiency caused by the dispenser, since the sealing frame is not used, the thickness control and range control of the sealing resin cannot be sufficiently performed, and There is a drawback that the dimensional accuracy becomes poor. In addition, if the potting method does not use a sealing frame, the resin will sag, and the thickness variation of the resin will inevitably become large (usually about ± 400 μm to ± 600 μm). Therefore, in the case of a multi-piece substrate or the like, the amount to be cut is different and sufficient cutting accuracy cannot be obtained. As a result, there is a drawback in that the resin cannot be made uniform in thickness.

The present invention has been made to solve the above problems, and a first object thereof is to provide a method for sealing an electronic component excellent in cost efficiency, productivity and dimensional accuracy. . A second object of the present invention is to provide a surface grinding apparatus for grinding a sealing resin, which is suitable for carrying out the sealing method.

[0009]

In order to solve the above-mentioned problems, in the invention according to claim 1, a sealing resin is applied to the substrate so that the electronic components mounted on the substrate are covered. The gist is a method of sealing an electronic component, in which after printing and curing the sealing resin, the upper surface of the cured sealing resin is ground.

Particularly, in claim 1, a metal mask having a supply port larger than a projected area of the electronic component to be sealed is arranged on the substrate, and the sealing resin is moved to move the electronic resin mounting region by moving the squeegee. It can also be printed on.
Further, regarding grinding, the upper surface of the cured sealing resin can be ground using a surface grinding machine.

Grinding using a polishing member having a 180th to 240th abrasive adhered to the surface, and then performing grinding using a 320th to 500th abrasive adhered to the surface. You can also There is also a method of manufacturing a semiconductor package in which an electronic component is mounted on a substrate for mounting an electronic component, and then the electronic component is resin-sealed by the sealing method according to claim 1 and surface-ground.

According to the second aspect of the invention, the endless polishing belt is wound between the driving roller and the contact roller and has an abrasive material fixed on the surface thereof, and the sealing resin is printed. A table for fixing the substrate, a driving means for relatively moving the polishing belt and the table, and a vacuuming means for performing vacuuming via a suction hole opened on the upper surface of the table,
While being arranged between the substrate and the table,
The gist of the invention is a surface grinding device for grinding a sealing resin, which is provided with at least a lower portion of an electronic component mounting area and a plate-shaped jig having a communication hole that communicates between the suction hole.

According to a third aspect of the present invention, in the second aspect, at least the upper surface of the table is made of iron, and the plate jig is a flexible magnet sheet.

[0014]

According to the invention described in claim 1, since the sealing resin is formed by the printing method which is excellent in the forming accuracy in the thickness direction and the plane direction, the thickness variation of the sealing resin can be prevented. Get smaller. Therefore, the surface grinding can be performed easily and highly accurately in the post process.

In the printing method, the sealing resin is pushed out from the supply port by the movement of the squeegee so that a predetermined amount of the sealing resin is transferred to the electronic component mounting area on the substrate. At this time, by setting the thickness of the metal mask and the size of the supply port in advance, the printing thickness and printing range of the sealing resin can be controlled.

Further, regarding the grinding, it is possible to improve such that when the rotating polishing belt is brought into contact with the substrate, the upper surface of the sealing resin is scraped off flat by the abrasive adhered to the surface of the polishing belt. is there. As a result, the sealing resin is controlled to have a predetermined thickness. Further, since it is dry grinding that does not use a grinding liquid, there is no need for equipment for supplying and circulating the grinding liquid, and there is no contamination of the substrate by the grinding liquid.

Further, an improvement can be made in which rough grinding is first performed with a coarse abrasive having a small count, and then final grinding is performed with a fine abrasive having a larger count.
Such grinding not only improves the grinding accuracy but also improves the grinding efficiency.

According to the second and third aspects of the present invention, the substrate is brought into close contact with the plate-like jig by evacuation through the suction hole and the communication hole, and as a result, the substrate is securely placed on the upper surface of the table. Fixed to. Therefore, when performing grinding with the rotating polishing belt, high grinding accuracy is ensured. Further, since the plate-shaped jig is arranged between the substrate and the table, the substrate does not come into direct contact with the upper surface of the table.

According to the third aspect of the invention, the magnet sheet is surely attracted to the upper surface of the table by the magnetic force. Also, with this fixing method, the attachment and detachment of the magnet sheet is relatively easy. Further, the flexible magnet sheet absorbs the impact during the surface grinding process, so that the substrate is not easily scratched.

[0020]

【Example】

[Embodiment 1] An embodiment in which the present invention is embodied in a method of manufacturing a semiconductor package for an IC card will be described in detail below with reference to FIGS.

In this embodiment, the semiconductor package 2 is manufactured by performing a die bonding process, a wire bonding process and a resin sealing process (a resin printing process, a resin curing process and a surface grinding process) on the electronic component mounting substrate 1. are doing. Before describing each step in detail, first, the configurations of instruments and devices used in the resin sealing step will be described.

The resin encapsulation process of this embodiment is mainly composed of three processes including a resin printing process, a resin curing process and a surface grinding process. As shown in FIG. 3, in the resin printing process, a general screen printer 3 is used as a means for printing the resin. The screen printer 3 includes a table 4 for fixing the electronic component mounting substrate 1 during printing, a metal mask 5, a squeegee 6, and the like. A plurality of supply ports 5a are formed at predetermined locations of the metal mask 5 (that is, locations corresponding to the electronic component mounting area R of the substrate 1). Each of the supply ports 5a has a projected area (5 mm × 5) of the IC chip 7 which is an electronic component to be sealed.
mm = 25 mm ² ). The thickness of the metal mask 5 is set to be slightly larger than the height of the wire loop when the IC chip 7 is wire-bonded. In this embodiment, the metal mask 5 has a thickness of 5
It is set to 00 μm. Here, the metal mask 5
By previously setting the thickness of the resin and the size of the supply port 5a, the printing thickness and the printing range of the resin are controlled.

FIG. 7 schematically shows a wet and grinding wheel type surface grinding device 8 used in the surface grinding process. The surface grinding apparatus 8 includes a grinding wheel head 10 including a grinding wheel 9, a belt conveyor 11, a grinding wheel head driving means (not shown), a table 13 having an iron plate 12 on its upper surface, a vacuum pump (not shown), and a grinding fluid circulation pipe 14. A magnet sheet 15 as a plate-shaped jig is provided.

A table 13 is provided on the belt conveyor 11.
Is mounted so that it can be moved horizontally. Inside the table 13, a passage 13a for vacuuming is formed which communicates with a vacuum pump provided outside the table 13. An iron plate 12 having excellent flatness is fixed to the upper surface of the table 13. As shown in FIG. 6, the iron plate 12 is regularly formed with a plurality of suction holes 16 having a substantially circular cross section. On the upper surface of the iron plate 12, a flexible magnet sheet (thickness: about 1 mm) 15 as a plate jig is attracted by magnetic force. The magnet sheet 15 is produced, for example, by applying a resin paste containing magnetic powder onto the surface of a resin or rubber base. Like the iron plate 12, the magnet sheet 15 also has excellent flatness.
The magnet sheet 15 is arranged on the iron plate 12 with its magnetic surface facing downward.

The magnet sheet 15 is formed with a plurality of communication holes 17 for communicating the lower part of the electronic component mounting area R and the suction holes 16. Therefore, when the iron plate 12 and the magnet sheet 15 are arranged on the table 13 to perform vacuuming, air is discharged through the communication hole 17, the suction hole 16 and the passage 13a. Then, the substrate 1 is brought into close contact with the magnet sheet 15, and as a result, the substrate 1 is attached to the table 1.
It is securely fixed to the upper surface of No. 3.

As shown in FIGS. 5 and 7, above the belt conveyor 11, a grinding wheel head 10 having a grinding wheel 9 is arranged at a predetermined distance. Whetstone head 1
The position of 0 can be adjusted on the order of several μm by a height adjusting mechanism (not shown). The grinding fluid is supplied to the grindstone head 10 from the polishing fluid circulation pipe 14. Further, the supplied grinding fluid is circulated in the grinding fluid circulation pipe 14 via a recovery means, a filter, a pump and the like which are not shown. The grinding liquid is for avoiding the temperature rise of the grinding portion by reducing the sliding resistance of the rotating grinding wheel 9.

As shown in FIG. 5, the grinding wheel 9 comprises an abrasive 20 fixed to the outer peripheral surface of a base metal 19 with a binder 18. In this example, 240th CB
Two wheels, a grinding wheel 9 using an abrasive 20 made of N (Cubic boron nitride) and a grinding wheel 9 using an abrasive 20 made of CBN of 400 count are used.

Next, a procedure for manufacturing the semiconductor package 2 will be described. 1 and 6 schematically show an electronic component mounting substrate 1 used in a die bonding process. This board (length 250mm, width 33mm, thickness 15
0 μm) 1 is a so-called multi-piece flexible substrate having electronic component mounting regions R at 36 places.
A conductor pattern 21 is formed on the lower surface of the substrate 1.
A thin gold plating (not shown) is applied to the conductor pattern 21. A part of the conductor pattern 21 is exposed by the five through holes 22 provided immediately around the electronic component mounting region R. That is, in this substrate 1, the exposed portion is the bonding pad 23.

In the die bonding step, first, the die bonding resin 24 is printed on the electronic component mounting region R of the substrate 1 by using the printing means of a conventionally known die bonding apparatus. In this embodiment, a commonly used insulating epoxy resin is selected. Next, the IC chip 7 is mounted on the die bonding resin 24 using the mounter of the die bonding apparatus. Then, the die bonding resin 24 is cured by curing at a predetermined temperature.

The substrate 1 that has undergone the die bonding process is conveyed to a wire bonder for performing the wire bonding process next. In the wire bonder, as shown in FIG. 2, an electrode (not shown) on the IC chip 7 side and a bonding pad 23 on the substrate 1 side are joined via a gold wire 25.

The substrate 1 that has undergone the wire bonding process is
Then, it is conveyed to the screen printing machine 3 described above. In the resin printing process by the screen printing machine 3, first, the metal mask 5 is arranged so as to be in close contact with the upper surface of the substrate 1 fixed on the table 4. Then, the squeegee 6 is moved in a predetermined direction while the sealing resin 26 is supplied to the upper surface of the metal mask 5. Then, the moving squeegee 6 pushes out the sealing resin 26 from the supply port 5a, and the substrate 1
A predetermined amount of the sealing resin 26 is transferred to the upper electronic component mounting area R. As a result, as shown in FIG. 3, the IC chip 7, the gold wire 25, and the bonding pad 23 are entirely resin-sealed. In this embodiment, an insulating epoxy resin is selected as the sealing resin 26.

After that, the metal mask 5 is removed, and the substrate 1 is heat-treated at a predetermined temperature in a curing device for carrying out a resin curing step. Then, as shown in FIG.
The uncured encapsulating resin 26 cures while maintaining the shape when printed to some extent. In this embodiment, the set thickness of the sealing resin 26 after curing is 6
It is 00 μm, and the variation with respect to the set thickness is ± 120
It becomes about μm.

The substrate 1 that has undergone the resin curing step is then conveyed to the above-described surface grinding device 8. In the surface grinding process in the surface grinding device 8, first, the table 1 having the iron plate 12 is provided.
The substrate 1 is fixed to the upper surface of the substrate 3 via the magnet sheet 15. Next, after adjusting the height of the grindstone head 10,
The table 13 is horizontally reciprocated by the belt conveyor 11. Then, when the substrate 1 passes under the grindstone head 10, the rotating grinding wheel 9 contacts the upper surface of the substrate 1 as shown in FIG. As a result, the upper surface of the sealing resin 26, which is the protruding portion, is scraped off flat by the abrasive material 20.

In this embodiment, first, rough grinding is carried out by a grinding wheel 9 having a coarse abrasive material 20 of 240 count, and then finish grinding is carried out by a grinding wheel 9 having a fine abrasive material of 400 count. 1 for rough grinding
50 μm to 200 μm is ground, and 30 is used for finish grinding.
It is ground to about 40 μm to 40 μm. As a result, as shown in FIG. 8, the final set thickness of the sealing resin 26 is 580 μm.
The semiconductor package 2 is manufactured. At this time, the variation of the sealing resin 26 with respect to the final set thickness is ± 20.
It becomes about μm. In addition, the surface-ground sealing resin 26
The surface roughness of the upper surface of Ra is 0.5 μm to 2.5 μm.
Rmax = 5 μm to 20 μm.

In the method of manufacturing the semiconductor package 2 described above in detail, the sealing resin 26 is transferred by the screen printing method which is excellent in the forming accuracy in the thickness direction and the plane direction. Therefore, the thickness variation of the sealing resin 26 is smaller than that of the conventional potting method. Therefore, the amount to be cut is substantially equal in each sealing resin 26. Therefore, the upper surface of the sealing resin 26 can be surface-ground easily and with high accuracy. In particular,
In this embodiment, since two types of grinding wheels 9 are used for rough grinding and finish grinding, not only grinding accuracy but also grinding efficiency is excellent. Further, such highly accurate grinding makes it extremely unlikely that problems such as the upper surface of the sealing resin 26 being partially thinned or the gold wire 25 or the like being partially exposed occur. Therefore, the semiconductor package 2
Moisture resistance and reliability are improved.

Since the screen printing method using the metal mask 5 is adopted in this embodiment, the equipment cost is lower than that of the transfer molding method. Further, with the screen printing method, even when there are electronic component mounting regions R at a plurality of locations on a single substrate 1, the processing can be performed at once. Therefore, the production efficiency is superior to the potting method using a dispenser or the like.

According to the grinding wheel type surface grinding device 8 of this embodiment, the substrate 1 is securely fixed to the upper surface of the table 13 by vacuuming, so that a high grinding accuracy is ensured when the surface grinding is performed. You can Therefore, it is effective when the flexible substrate 1 is selected as in this embodiment. Further, since the flexible magnet sheet 15 is used, it is possible to reliably absorb the impact applied to the substrate 1 during the surface grinding process. Therefore, the soft material forming the substrate 1 (for example, gold plating of the conductor pattern 21 on the back surface) is not easily scratched, and the defective product generation rate is also reduced.

Further, if a plurality of magnet sheets 15 having different shapes of the communication holes 17 are produced, there is an advantage that the position of the suction holes 16 in the iron plate 12 does not have to be changed even if the dimensions of the substrate 1 are changed. . Therefore, the versatility of the surface grinding device 8 can be improved. In addition, the magnet sheet 15 has an advantage that it can be easily attached and detached. [Second Embodiment] Next, a method of manufacturing a semiconductor package according to a second embodiment will be described in detail with reference to FIGS. 1 to 4, 6, and 8 to 10.

Also in this embodiment, as in the first embodiment, the semiconductor package 2 is formed by the die bonding process, the wire bonding process and the resin sealing process (the resin printing process, the resin curing process and the surface grinding process) for the electronic component mounting substrate 1. Manufacturing. However, in the second embodiment, the surface grinding is performed by the surface grinding device 30 having a configuration different from that of the first embodiment.

FIG. 10 schematically shows a surface grinding device 30 used in the second embodiment. The surface grinding device 30 is a dry type and a belt type, and is a so-called belt sander.

The surface grinding device 30 includes a driving roller 31, a contact roller 32, a polishing belt 33, a support head 34 containing a motor (not shown), a belt conveyor 11,
A table 13 having an iron plate 12 on its upper surface, a vacuum pump (not shown), a magnet sheet 15 as a plate jig, and the like are provided. The dry surface grinding apparatus 30 is not provided with the grinding fluid circulation pipe 14 as in the first embodiment. Belt conveyor 11, iron plate 12, table 1
Since the configurations and functions of the magnetic sheet 3 and the magnet sheet 15 are basically the same as those in the first embodiment, detailed description thereof will be omitted here.

The drive roller 31 is integrally rotatably fixed to the rotary shaft of the motor built in the support head 34. Below the drive roller 31, a contact roller 32 is rotatably arranged at a predetermined distance. An endless polishing belt 33 as a grinding tool is wound around the drive roller 31 and the contact roller 32. Therefore, when the driving roller 31 is rotated by the motor, the driving force is transmitted through the polishing belt 33, and the contact roller 32 follows and rotates. The drive roller 31 and the contact roller 32 can be position-adjusted on the order of several μm by a height adjusting mechanism (not shown).

Here, the polishing belt 33 is a general term for belt-shaped types among the types of polishing cloth paper, and refers to what is called an abrasive belt or the like. The polishing belt 33, which can secure a long circumference, is characterized in that it has a relatively wide polishing surface and the amount of grinding work that a specific polishing material 20 handles per unit time is small. Also, the polishing belt 3 is automatically used during grinding.
Since 3 is air-cooled, there is also a feature that the temperature rise of the grinding portion hardly occurs.

As shown in FIG. 9, the polishing belt 33.
Is bonded to the outer peripheral surface of the base material 35 by the binder 18
It is made by fixing. In this embodiment, a polishing belt 33 using the abrasive material 20 made of 180th silicon carbide,
And a polishing belt 33 using the abrasive material 20 made of silicon carbide of 400 count.

In the method of manufacturing the semiconductor package 2 of the second embodiment, the die bonding process, the wire bonding process, the resin printing process and the resin curing process are first performed according to the procedure of the first embodiment.

The substrate 1 which has undergone the resin curing step is conveyed to the above-mentioned surface grinding apparatus 30. In the surface grinding process in the surface grinding device 30, first, the table 1 having the iron plate 12 is provided.
The substrate 1 is fixed to the upper surface of the substrate 3 via the magnet sheet 15. Next, after adjusting the height of the contact roller 32, the table 13 is horizontally reciprocated by the belt conveyor 11. Then, when the substrate 1 passes under the contact roller 32, as shown in FIG.
The rotating polishing belt 33 contacts the upper surface of the substrate 1. As a result, the upper surface of the sealing resin 26, which is the protruding portion, is scraped off flat by the abrasive material 20.

In this embodiment, first, rough grinding is performed by the polishing belt 33 having the coarse abrasive 20 fixed to the 180th count, and then finish grinding is performed using the polishing belt 33 having the fine abrasive 20 fixed to the 400th count. The rough grinding is about 150 μm to 200 μm, and the finish grinding is about 30 μm to 40 μm. as a result,
As shown in FIG. 8, the semiconductor package 2 in which the final setting thickness of the sealing resin 26 is 580 μm is manufactured.
At this time, the variation of the sealing resin 26 with respect to the final set thickness is about ± 20 μm. The surface roughness of the upper surface of the sealing resin 26 whose surface has been ground is Ra = 0.5 μm.
2.5 μm, Rmax = 5 μm to 20 μm.

It is obvious that even the method of manufacturing the semiconductor package 2 of the second embodiment as described above has the same effects as the first embodiment. Particularly, in this embodiment, since the grinding is a dry grinding method that does not use a grinding liquid, a facility for supplying and circulating the grinding liquid is not necessary. Therefore, the structure of the surface grinding device 30 is also simplified, and the cost can be reduced as a whole. Further, since the substrate 1 is not exposed to the grinding liquid, there is an advantage that, for example, the gold plating applied to the conductor pattern 21 does not have water stains. Therefore, the cleaning in the subsequent process is naturally unnecessary and the productivity is improved.

Further, in the case of the polishing belt 33 in which the temperature rise in the grinding portion is small, the resin portion constituting the substrate 1
In particular, it is possible to avoid the situation where the sealing resin 26 is deteriorated by heat. Therefore, the defective product generation rate can be reduced.

The present invention is not limited to the above embodiment, but can be modified as follows. (1) The grinding wheel type surface grinding device 8 of the first embodiment is used as a dry type, or the belt type surface grinding device 30 of the second embodiment is used.
May be used as a wet type. Of course, it is also possible to use a surface grinding machine of a type different from the surface grinding machines 8 and 30 illustrated in these embodiments. That is, a general surface grinding device can perform surface grinding with higher accuracy than a cutting device such as a planing machine.

(2) The sealing resin 26 is not limited to the insulating epoxy resin, but may be another thermosetting resin such as an insulating polyimide resin. (3) In the surface grinding devices 8 and 30 of Embodiments 1 and 2, driving means other than the belt conveyor 11 may be used. In addition, the table 1 is provided by the belt conveyor 11 and the like.
Not only the 3 side may be moved, but the grinding tool side such as the grinding wheel 9 and the polishing belt 33 may be moved. Of course, both the grinding tool and the table 13 may be moved.

(4) The abrasive 20 is not limited to the CBN and silicon carbide used in Examples 1 and 2. For example, fused alumina, garnet, emery, silica stone,
The abrasive 20 may be selected from iron oxide, zirconium carbide, silica stone, iron oxide, mullite, titanium nitride, silicon nitride, titanium carbide, diamond, boron carbide, and the like.
Further, the count of the abrasive material 20 can be freely changed and is not necessarily limited to the combination of the first and second embodiments.

(5) The substrate 1 used for manufacturing the semiconductor package 2 does not have to be flexible, and may be, for example, a rigid resin substrate. Further, not only a resin substrate but also a ceramic substrate or the like may be used.

(6) Depending on the type and material of the substrate 1 such as when there is no conductor pattern 21 on the back surface, for example, the plate jig 15 may be replaced with a non-flexible magnet sheet or may be flexible. In addition, a sheet containing no magnet powder may be used instead.

(7) Table 4 of the screen printing machine 3
A structure for vacuuming may be provided similarly to the surface grinding devices 8 and 30, and the magnet sheet 15 may be arranged on the upper surface thereof. In this way, the substrate 1 is reliably fixed to the table 4 during screen printing, so that the printing accuracy of the sealing resin 26 is further improved and the cutting accuracy in the surface grinding step is further increased.

(8) The electronic component to be sealed is not limited to the IC chip 7 shown in Embodiments 1 and 2, but may be various chip components or the like. Of course, the region where the IC chip 7 and the chip components are mounted can be entirely sealed with the sealing resin 26.

Here, in addition to the technical ideas described in the claims and the like, the technical ideas grasped by the above-described embodiments and other examples will be listed below together with their effects. (1) A magnet sheet arranged between an iron plate material on the upper surface of a table and a workpiece, comprising a communication hole that connects a lower portion of a predetermined region of the workpiece and a suction hole of the iron plate material. Magnet sheet. This magnet sheet can improve the versatility of a flat polishing apparatus and the like.

(2) A screen printing machine provided with a vacuuming means for fixing an object to be printed, the technical concept 1
Screen printing machine with a magnet sheet. With this configuration, the cutting accuracy in the surface grinding process is further increased.

(3) A grinding wheel having a polishing surface, a rotation driving means for rotating the grinding wheel, a table for fixing a substrate on which a sealing resin is printed, the grinding wheel and the table Is arranged between the substrate and the table, and a driving means for relatively moving the table and a vacuum drawing means for drawing a vacuum through a suction hole opened on the upper surface of the table. A grinding wheel type surface grinding device for grinding a sealing resin, which includes a plate-shaped jig having a communication hole that communicates between a lower portion of a component mounting area and the suction hole. With this device, it is possible to reduce the defective product generation rate, secure grinding accuracy, and improve productivity and versatility.

The technical terms used in this specification are defined as follows. "Electronic parts: ICs made of silicon, gallium arsenide, etc.
In addition to semiconductor components such as chips and LSI chips, chip components such as chip transistors, chip diodes, chip resistors, chip capacitors, and chip inductors are also referred to. "

[0061]

As described in detail above, according to the electronic component sealing method of the first aspect, since the sealing resin formed by the printing method is subjected to surface grinding, Cost efficiency, productivity, and dimensional accuracy can be improved.
In particular, according to the invention of the second embodiment described as an improvement plan, since the substrate is not exposed to the grinding liquid, it is possible to reduce the influence on the constituent material of the substrate in the surface grinding process. Moreover, according to the invention described in claims 2 and 3,
It is possible to reduce the defective product generation rate when performing the sealing method, secure grinding accuracy, and improve productivity and versatility.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an electronic component mounting substrate before an IC chip is mounted in a method for manufacturing a semiconductor package according to a first embodiment.

FIG. 2 is likewise a schematic cross-sectional view showing a state in which wire bonding is performed on an IC chip mounted on a substrate.

FIG. 3 is likewise a schematic cross-sectional view showing a state in which a sealing resin is printed.

FIG. 4 is likewise a schematic cross-sectional view showing a state where the printed sealing resin is cured.

FIG. 5 is likewise a schematic cross-sectional view showing a ground state of the sealing resin.

FIG. 6 is likewise a partial schematic exploded perspective view showing a substrate, a magnet sheet and an iron plate.

FIG. 7 is likewise a partial schematic front view showing a wet and grinding wheel type surface grinding device for grinding a sealing resin.

FIG. 8 is likewise a schematic cross-sectional view showing a state in which the sealing resin has been ground.

FIG. 9 is a schematic cross-sectional view showing a state in which the sealing resin is ground in the method for manufacturing a semiconductor package according to the second embodiment.

FIG. 10 is also a partial schematic front view showing a dry and belt type surface grinding device for polishing the sealing resin.

[Explanation of symbols]

1 ... (Electronic component mounting) substrate, 2 ... Semiconductor package,
13 ... Table, 5a ... Supply port, 5 ... Metal mask, 6
... Squeegee, 7 ... IC chip as an electronic component, 8, 3
0 ... Surface grinder, 11 ... Belt conveyor as driving means, 15 ... Magnet sheet as plate jig, 16
... Suction hole, 17 ... Communication hole, 20 ... Abrasive material, 26 ... Sealing resin, 31 ... Driving roller, 32 ... Contact roller, 3
3 ... Polishing belt, R ... Electronic component mounting area.

Claims (3)

[Claims] 1. An encapsulation resin is printed on the substrate so that the electronic components mounted on the substrate are covered with the encapsulation resin, and the encapsulation resin is cured. A method for sealing electronic components by grinding. 2. An endless polishing belt which is wound between a driving roller and a contact roller and has an abrasive adhered to its surface, and a table for fixing a substrate on which a sealing resin is printed. A driving means for moving the polishing belt and the table relative to each other, a vacuuming means for performing a vacuuming via a suction hole opened on the upper surface of the table, and a space between the substrate and the table. Is located at
A surface grinding device for grinding a sealing resin, which is provided with at least a lower portion of an electronic component mounting area and a plate-shaped jig having a communication hole for communicating the suction hole. 3. A surface grinding apparatus for grinding a sealing resin according to claim 2, wherein at least an upper surface of the table is made of iron and the plate-shaped jig is a magnet sheet having flexibility.