JP2007300006A - Dust removal device, and method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make it possible to remove dust in a package securely, and to prevent resticking prior to the sealing of the package on which a semiconductor chip is mounted in the manufacturing of the semiconductor device in which the semiconductor chip is contained in a cavity. <P>SOLUTION: The dust removal device is made to be a structure having a dust suction 12 such as dust suction nozzle 14 etc. which opens facing to the inside of a package 1 or to the surface of a semiconductor chip 2. Since it has a dust suction structure where dust hardly disperse fundamentally, that is, the dust suction nozzle 14 is made to open in the vicinity of the inside of the package 1 or the surface of the semiconductor chip 2, the flow velocity in the suction is made large enabling secure suction of dust. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a dust removing apparatus and method for manufacturing a semiconductor device.

  When manufacturing and assembling a semiconductor device in which a semiconductor chip is housed in a package cavity, the semiconductor chip is mounted in the package cavity and electrically connected to a conductor such as wiring provided in the package by wire bonding or the like. Later, a cover material such as a cover glass is disposed on the upper surface of the package and sealed.

  However, dust may adhere to the inner surface of the package and the surface of the semiconductor chip before sealing with the lid member, and dust attached to the inner surface of the package may move after sealing and adhere to the surface of the semiconductor chip. When the semiconductor chip is a CCD chip, if dust of 5 μm or more adheres to the pixel surface, it is displayed as a scratch on the screen, which is a problem. Therefore, in order to improve the yield, it is necessary to remove dust or the like prior to sealing, and the dust in the package is scattered by air blow, and the scattered dust is sucked.

A conventional dust removing apparatus is shown in FIG. In FIG. 4A, reference numeral 1 denotes a semiconductor device being manufactured. The semiconductor chip 2 is mounted in the cavity 4 of the package 3 and bonded to a conductor (not shown) provided in the package 3 with a thin metal wire 5. It is sealed with. Reference numeral 7 denotes a transport carrier that positions the semiconductor device 1 at a predetermined dust removal position.
Reference numeral 50 denotes a dust removing unit of the dust removing device. An air blow nozzle 52 is provided at the center of a cap-type cover body 51 that covers the cavity 4 of the package 3, and a dust suction hole 53 that opens at the lower inner periphery of the cover body 51 is provided. In the figure, 54 is a dust suction port, 55 is an air supply port, 56 is an in-line filter, 57 is a flow meter, 57 is a vacuum pressure reducing valve, 59 is an ionizer, 60 is a clean filter, 61 is an in-line filter, 62 is a flow meter, 63 Is a regulator, and 64 is a dryer.
At the time of dust removal processing, the lower end of the cover body 51 is brought into contact with the upper surface of the package 3 and air is blown from the air blow nozzle 52 in a state where the inside of the package 3 is sealed, and dust adhered to the inner surface of the package 3 and the semiconductor chip 2 is removed. While being scattered, the scattered dust is sucked into the dust suction hole 53 and removed outside the cover body 51. At this time, the balance between the air blow and the dust suction is such that the air blow flow rate> the dust suction flow rate, so that the internal pressure of the sealed space formed by the cover body 51 is slightly higher than the outside to prevent the inflow of dust from the outside. To do.

  After performing such dust removal processing for about 5 to 10 seconds, air blow and dust suction are stopped, the dust removal unit 50 is raised as shown in FIG. 4B, and as shown in FIG. The processed semiconductor device 1 is sent out by the transport carrier 7 and the semiconductor device 1 to be processed next is positioned. Then, the dust removal process is performed again in the state shown in FIG.

As another dust removing device, an air ejection nozzle is formed in the center of the head arranged above the semiconductor device, and a dust suction port is provided around the air ejection nozzle so as to be located outside the package cavity. The air ejection nozzle is positioned directly above the cavity, and air is ejected vertically toward the cavity so that the dust in the package is scattered around the air ejection flow, and the scattered dust is sucked from the dust suction port. In some cases, the scattered dust is removed before it diffuses widely (Patent Document 1).
JP 2003-158048 A

The conventional dust removing apparatus described with reference to FIG. 4 has the following problems.
In the dust removing unit 50, as shown in an enlarged view in FIG. 5, the distance (blow distance) L1 from the outlet of the air blow nozzle 52 to the top surface of the chip to be processed is the air blowing area (blow area) of the entire bottom surface of the cavity. A is set so as to satisfy a predetermined mathematical formula in relation to the package maximum dimension (cavity maximum dimension) and the nozzle diameter B so as to be A. Therefore, up to a certain distance from the outlet of the air blow nozzle 52, a potential core (symbol C in FIG. 5) in which the air flow velocity, dynamic pressure, and kinetic energy are stored is formed, while the outside of the potential core is the surrounding air. As shown in FIG. 6, the dust D scattered from the inner surface of the package 3 and the surface of the semiconductor chip 2 is entrained in the air blow while being sucked into the dust suction hole 53, as shown in FIG. In some cases, it descends and collides with the surface of the semiconductor chip 2 to cause damage or reattachment.

  Further, as described above, at the time of dust removal processing, the lower surface of the cover body 51 is brought into contact with the upper surface of the package 3 in order to prevent dust from scattering to the surroundings, so that the air directly hits the package 3. Therefore, the dust removing unit 50 receives the lifting force and needs to be pressed against the package 3 with a force stronger than the lifting force. Therefore, when the package 3 is a relatively fragile material such as a ceramic material, when the dust removal unit 50 is raised as shown in FIG. After that, it may drop due to gravity and reattach to the inner surface of the package 3 or the semiconductor chip 2.

  Further, as shown in FIG. 8, dust D adhering to the periphery of the air blow nozzle 52 and the dust suction hole 53 and in the dust suction pipe during the dust removal process falls when the air blow and dust suction are stopped, and the inner surface of the package 3 is removed. In some cases, it reattaches on the semiconductor chip 2 or the like.

  In the dust removing device described in Patent Document 1, the dust in the package is sucked from the dust suction port while being scattered around the air jet flow, and the principle is the same as that of the dust removing device in FIG. It was difficult to reliably prevent this.

  The present invention solves the above problems, and an object thereof is to provide a dust removing device and a dust removing method that can reliably remove dust in a package and prevent reattachment.

  In order to solve the above-mentioned problems, the present invention basically has a dust suction structure in which dust is hardly scattered, that is, the dust suction part is disposed in close proximity to the inner surface of the package or the surface of the semiconductor chip. Therefore, the flow rate during suction was increased, and dust was reliably sucked and removed.

  That is, the dust removing apparatus of the present invention removes dust in a package prior to sealing the package on which the semiconductor chip is mounted when manufacturing a semiconductor device in which the semiconductor chip is accommodated in the cavity of the package. And it has the dust suction part opened facing the inner surface of the said package or the surface of a semiconductor chip, It is characterized by the above-mentioned. It is particularly convenient when the semiconductor chip is an optical element.

The dust suction unit is characterized in that it can move in a direction approaching and separating from the upper surface of the semiconductor chip.
It has a cover body capable of contacting the package and sealing the inside of the package, and an air supply portion opened to the cover body.

  The cover body is formed in a cylindrical shape, and the cylindrical dust suction portion moves in the cover body in a direction approaching and separating from the upper surface of the semiconductor chip. The cover body is formed by being divided into a lower cylinder body connected to the end face of the package and an upper cylinder body holding the dust suction portion, and a non-dust-generating elastic material between the lower cylinder body and the upper cylinder body. The body is interposed.

The air supply unit communicates with the clean room through a filter, and performs natural intake so that the sealed space formed by the cover body is at atmospheric pressure.
In the dust removing method of the present invention, when manufacturing a semiconductor device in which a semiconductor chip is accommodated in a cavity of a package, the package on which the semiconductor chip is mounted is covered with a cover body and sealed before sealing. The dust in the package is removed by sucking with a dust suction part provided at a predetermined suction position facing the inner surface of the package or the surface of the semiconductor chip.

  After sucking for a predetermined time by a dust suction portion opened at a predetermined suction position, the dust suction portion is raised to a predetermined upper position while continuing the suction, and then the cover body is separated from the package. .

  As described above, the dust removing device of the present invention opens the dust suction part in close proximity to the inner surface of the package or the surface of the semiconductor chip, thereby increasing the flow velocity during suction and reducing the dust. Can be reliably aspirated and removed.

  In addition, the dust suction part is movable up and down so that it can be sucked while the inside of the package is sealed with the cover body and when it is released from the seal. It is possible to prevent reattachment to the inner surface or the surface of the semiconductor chip. Even if the dust falls, suction by the dust suction unit is always performed, so that floating dust can be sucked and removed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a configuration of a dust removing apparatus according to an embodiment of the present invention.
Reference numeral 1 denotes a semiconductor device that is being processed and is being manufactured. The semiconductor chip 2 is mounted on the bottom surface in the cavity 4 of the package 3 and bonded to a conductor (not shown) provided in the package 3 with a thin metal wire 5. In the subsequent process, the lid 6 is sealed as indicated by the phantom line. When the semiconductor chip 2 is a CCD chip, the CCD pixel surface is mounted as an upper surface, and a cover glass as the lid member 6 is fixed with a UV curable resin or the like. Such a semiconductor device 1 is about 0.1 to 1 g, and handling of the semiconductor device 1 between facilities and processes is performed by a dedicated carrier 7. However, the semiconductor chip 2 may be an optical element other than a CCD chip or may not be an optical element.

  The dust removing unit 10 of the dust removing device includes a cover body 11 that can seal the inside of the package 3 in contact with the package 3, and a dust suction unit that opens to face the upper surface of the semiconductor chip 2 (or the inner surface of the package 3). 12 and an air supply port 13 opened to the cover body 11.

The cover body 11 is formed in a cylindrical shape, and slides in a direction in which the cylindrical dust suction portion 12 approaches and separates from the upper surface of the semiconductor chip 2 while sealing the space between the cover body 11 and the cover body 11. . A dust suction nozzle 14 having an inner diameter of 2 to 3 mm is coaxially attached to one end of the dust suction portion 12.
The cover body 11 is formed by being divided into a lower cylinder body 12 a connected to the end face of the package 3 on the lower surface and an upper cylinder body 11 b holding the dust suction part 12. The air supply port 13 and the air supply hole 15 described above are formed in the lower cylindrical body 12a so as to open on the inner peripheral surface thereof.

  The air supply port 13 is connected to a clean room 17 as an air supply source through an air supply line 16. The air supply line 16 includes, in order from the clean room 17 side, a dryer 18 for removing moisture contained in the driving air, an in-line filter 19 for removing dust of 10 μm or more contained in the air, and 0.01 μm contained in the air. A clean filter 20 for removing the above dust and an ionizer 21 for removing the charge of the semiconductor or dust are disposed, and suction by the dust suction nozzle 14 is performed so that the sealed space formed by the cover body 11 becomes atmospheric pressure. As a result, air is naturally sent in, and dust is prevented from flowing into the air.

  The other end of the dust suction unit 12 is connected to the decompression device 23 through the exhaust line 22. In the exhaust line 22, a vacuum pressure reducing valve 24, a flow meter 25, and an in-line filter 26 are disposed in order from the pressure reducing device 23 side.

  The cover body 11 and the dust suction unit 12 have the following air bearing structure so that the dust suction unit 12 is integrated with the dust suction nozzle 14 and can always move in the vertical direction with a sliding resistance 0. .

  The dust suction portion 12 has a uniform hole diameter from the upper end to the lower end, but the outer shape has a portion having a large diameter over a predetermined length in the central portion in the axial direction, and protrudes like a bowl at the upper end of the central portion. There is a part that did. Hereinafter, the large diameter portion of the central portion is referred to as a medium diameter portion 27, the bowl-shaped portion is referred to as a large diameter portion 28, and the other portions are referred to as an upper small diameter portion 29 and a lower small diameter portion 30.

  The cover body 11 includes an upper small-diameter opening 31 that is in sliding contact with the upper small-diameter portion 29 of the dust suction section 12, a large-diameter opening 32 that is in sliding contact with the large-diameter portion 28, and a medium-diameter opening 33 that is in sliding contact with the medium-diameter portion 27. And a lower small-diameter opening 34 that is in sliding contact with the lower small-diameter portion 30.

  The size of the cover body 11 and the dust suction part 12 is such that the large diameter part 28 of the dust suction part 12 hits the stepped part between the upper small diameter opening part 31 and the large diameter opening part 32, the large diameter opening part 32 and the middle part. It can move up and down by a predetermined distance over the lower limit position corresponding to the stepped portion with the diameter opening portion 33, and when the large diameter portion 28 is lowered to the lower limit position, only the medium diameter portion 27 is in the medium diameter opening portion 33. Instead, a part of the lower small diameter portion 30 is located and a gap is set on the outer peripheral side of the lower small diameter portion 30.

  In the cover body 11, an upper thrust port 35 is formed in the large-diameter opening 32, and a lower thrust port 36 is formed in a position below the medium-diameter opening 33 and where the above-described gap is formed. The upper thrust port 35 and the lower thrust port 36 are respectively connected to air supply lines 39 and 40 having regulators 37 and 38 interposed therebetween.

  In the cover body 11, a pressurization port 41 is formed between the upper thrust port 35 and the lower thrust port 36, that is, an upper portion of the medium diameter opening 33, and an air groove 46 connected to the pressurization port 41 has a medium diameter. Formed on the inner peripheral surfaces of the opening 33 and the lower small-diameter opening 34, a porous block 47 is disposed in the air groove 46. The pressurization port 41 is connected to an air supply line 45 that includes a clean filter 42, an in-line filter 43, and a regulator 44.

  FIG. 2A shows a dust suction state. The semiconductor device 1 to be processed is positioned at a predetermined dust removal position by the transport carrier 7, and the cover body 11 of the dust removal unit 10 covers and seals the cavity 4 of the package 3. In the cover body 11, the dust suction part 12 is at the lower limit position due to the pressure of the upper thrust port 35, and the dust suction nozzle 14 opens at a height of 0.5 mm from the upper surface 2 a of the semiconductor chip 2.

  In this state, suction is performed through the dust suction nozzle 14. As a result, clean air is naturally fed into the sealed space through the air supply hole 15, and the dust adhered to the inner surface of the package 3 and the surface of the semiconductor chip 2 is peeled off by this air flow, and the air flow is accompanied. It is removed to the outside of the cover body 11 through the dust suction nozzle 14. At the time of this suction, it is necessary to pay attention to the amount of air sucked from the air supply hole 15 so that the sealed space formed by the cover body 11 does not become negative pressure.

  After the suction for 5 to 10 seconds, as shown in FIG. 2 (b), the dust suction part is increased by raising the pressure of the lower thrust port 36 while lowering the pressure of the upper thrust port 35 while keeping the suction. 12 is raised to increase the distance between the dust suction nozzle 14 and the upper surface of the semiconductor chip 2 and stop at a prescribed position. This position is set in advance as a position where the suction force of the suction nozzle 14 is less than the weight of the semiconductor device 1 to be processed.

  Next, as shown in FIG. 2 (c), the entire dust removing unit 10 is raised by raising the cover body 11 by a driving means (not shown) while suctioning. As a result, the cavity 4 of the package 3 is opened, and at the same time, the air supply from the air supply hole 15 is naturally stopped. After the dust removal unit 10 is raised, the processed semiconductor device 1 is carried out by the transport carrier 7 and the next semiconductor device 1 to be processed is positioned at the dust removal position.

Thereafter, the dust removing unit 10 is lowered to seal the cavity 4 of the package 3 (the arrangement is the same as that in FIG. 1B).
Thereafter, the pressure of the lower thrust port 36 is lowered while the pressure of the upper thrust port 35 is raised, thereby lowering the dust suction part 12 and again lower limit position shown in FIG. 1A, that is, the dust suction nozzle 14. Is stopped at a predetermined position at a height of 0.5 mm from the upper surface of the semiconductor chip 2. In this state, dust is removed in the same manner as described above.
As described above, the dust removing device is configured so that the dust suction nozzle 14 is movable up and down integrally with the dust suction unit 12 and is independent of the cover body 11 holding the upper surface of the package 3 without stopping dust suction. Then, the cover body 11 is also lifted to open the cavity 4 of the package 3.

  As a result, it is possible to effectively prevent dust adhering to the periphery of the dust suction nozzle 14 or in the dust suction pipe from dropping and reattaching to the inner surface of the package 3 or the upper surface of the semiconductor chip 2. Become. Even if the dust falls, since the suction by the dust suction nozzle 14 is always performed, the floating dust can be sucked and removed.

  That is, in the first stage, dust adhering to the inner surface of the package 3 and the surface of the semiconductor chip 2 is peeled off by nozzle suction, and is removed to the outside of the cover body 11 through the dust suction nozzle 14 along with the air flow. .

In the second stage, the dust suction unit 12 is raised to reduce the suction force on the inner surface of the package 3 and the surface of the semiconductor chip 2, sucking only floating dust, and the dust suction nozzle 14 along with the air flow. And removed to the outside of the cover body 11. Moreover, the floating dust accompanying the raising of the cover body 11 holding the package 3 is similarly removed.
A plurality of dust suction nozzles 14 may be installed in accordance with the shape of the package 3, thereby enhancing the dust removal effect. If a plurality of dust removal units 10 cannot be installed at the same time, a plurality of dust removal units 10 with different positions of the dust suction nozzles 14 may be installed along the line of the transport carrier 7 to remove dust at each position.

  As shown in FIG. 3, if a non-dust-generating elastic body 48 such as silicon is interposed between the lower cylinder 11 a and the upper cylinder 11 b of the cover body 11, the upper surface of the package 3 is covered. The lower cylindrical body 11a can be easily copied, and the adhesion can be improved.

  As described above, the dust removal apparatus and method of the present invention are useful for dust removal in a package in the process of manufacturing a semiconductor device. In particular, when an optical element such as a CCD chip is used, dust is re-applied to an optical part. It is possible to reduce defects due to scratches caused by adhesion or dust.

Sectional drawing which shows the structure of the dust removal apparatus in one Embodiment of this invention. Sectional drawing explaining the dust removal method by the dust removal apparatus of FIG. Sectional drawing which shows the structure of the dust removal apparatus in other embodiment of this invention. Sectional drawing explaining the structure of the conventional dust removal apparatus, and the dust removal method by it 4 is a partially enlarged sectional view of the dust removing device of FIG. Sectional drawing explaining the dust reattachment condition in the dust removal apparatus of FIG. Sectional drawing explaining the other dust reattachment condition in the dust removal apparatus of FIG. Sectional drawing explaining the further dust reattachment condition in the dust removal apparatus of FIG.

Explanation of symbols

1 Semiconductor Device 2 Semiconductor Chip 3 Package 4 Cavity
10 Dust removal unit
11 Cover body
11a Lower cylinder
11b Upper cylinder
12 Dust suction part
13 Air supply port (air supply part)
14 Dust suction nozzle
17 Clean room
19 Inline filter
20 Clean filter
48 Elastic body D Dust

Claims (9)

  A dust removing device that removes dust in a package prior to sealing a package on which the semiconductor chip is mounted when manufacturing a semiconductor device in which a semiconductor chip is stored in a cavity of the package, A dust removing device having a dust suction portion that opens to face the surface of a semiconductor chip.   The dust removing apparatus according to claim 1, wherein the semiconductor chip is an optical element.   2. The dust removing device according to claim 1, wherein the dust suction part is movable in a direction approaching and separating from the upper surface of the semiconductor chip.   The dust removing device according to any one of claims 1 to 3, further comprising: a cover body that can contact the package and seal the inside of the package; and an air supply portion that opens to the cover body.   The dust removing device according to claim 4, wherein the cover body is formed in a cylindrical shape, and the cylindrical dust suction portion moves in a direction in which the cover dust body approaches and separates from the upper surface of the semiconductor chip.   The cover body is formed by being divided into a lower cylinder body connected to the end face of the package and an upper cylinder body holding the dust suction part, and a non-dust-generating elastic body between the lower cylinder body and the upper cylinder body The dust removing device according to claim 4, wherein   2. The dust removing device according to claim 1, wherein the air supply unit communicates with the clean room via a filter and performs natural intake so that a sealed space formed by the cover body is at atmospheric pressure.   When manufacturing a semiconductor device in which a semiconductor chip is accommodated in a cavity of a package, the package on which the semiconductor chip is mounted is covered and sealed with a cover body prior to sealing, and the inner surface of the package or the semiconductor provided on the cover body A dust removing method for removing dust in the package by sucking with a dust suction part opened at a predetermined suction position facing the surface of the chip.   9. The cover body is separated from the package after the dust suction part is lifted to a predetermined upper position while suction is continued after the dust suction part opened at the predetermined suction position for a predetermined time. Dust removal method.

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