JP2003340875A - Cleaning method of component in resin molding and apparatus therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning method to remove deposit on a component, for example a mold when a chip is sealed with a resin, a substrate, a package or the like, when resin molding is carried out by using the mold, and an apparatus therefor. <P>SOLUTION: The cleaning apparatus is provided with a lamp unit 14 having an excimer lamp 15, a rail 17 moving the lamp unit 14 and a gas supply pipe 12 emitting a nitrogen gas in the vicinity of the mold face of an upper mold 3 and a lower mold 4. In a condition that a film is absent between the upper mold 3 and the lower mold 4, the lamp unit 14 is moved between the upper mold 3 and the lower mold 4 and the mold face of cavities 7 and 10 or the like is irradiated by an excimer ultraviolet light 18 for a specific time. Owing to this, the energy of the excimer ultraviolet light 18 breaks down the molecular bond of the deposit on the mold face, and an active oxygen generated by the excimer ultraviolet light 18 oxidizes, decomposes and volatilizes the deposit. The volatilized deposit is removed from an exhaust pipe 13. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to constituent elements in the case of producing a molded product by resin molding, for example, a metal mold for resin molding, an insert member before resin molding,
And to remove the deposits on the molded products after resin molding,
The present invention relates to a cleaning method and device.

[0002]

2. Description of the Related Art Recently, molded products manufactured by resin molding are required to have higher and higher quality, for example, good dimensional accuracy and appearance quality. For this reason, it is even more important to secure mold releasability between the mold and the molded product. Therefore, in order to facilitate the release of the molded product, with a synthetic resin film stretched along the mold surface of the mold,
A method of pressurizing a molten resin and injecting it into a cavity to mold the resin is used. By using such a film, the molded product can be easily released from the mold, so that good dimensional accuracy and appearance quality can be secured.

Here, as an example of resin molding, a chip shape mounted on a component molded in an appropriate position in a molded product, that is, a lead frame as an insert member, a printed circuit board or the like (hereinafter referred to as a substrate). The case where the electronic component (hereinafter, referred to as a chip) is sealed with resin will be described. In this case, a package such as an LSI is manufactured as a molded product by resin sealing. For such a package, not only dimensional accuracy and appearance quality but also high reliability is strongly required as quality. This resin encapsulation has a problem that the wire used for wiring between the chip and the substrate may be deformed or broken by the molten resin under pressure. Here, if a film is used at the time of resin sealing, a molten resin containing no release agent can be used, so that the resin fluidity is improved. Therefore, the moldability at the time of resin sealing is improved, and the deformation and disconnection of the wire are suppressed, so that the quality and yield of the package are improved.

Further, for the convenience of carrying the substrate before resin sealing, the substrate is also attached to an adhesive tape. In this case, the substrate can be stably transported while being attached to the adhesive tape. Furthermore,
For convenience when carrying the package after resin sealing,
It is also carried out that the package is attached to an adhesive tape.

[0005]

However, according to the above-mentioned conventional resin molding, there are cases where deposits mainly composed of organic substances are found at the locations shown in FIG. Hereinafter, as an example of resin molding, a case where a chip mounted on a substrate as an insert member is resin-sealed to manufacture a package such as an LSI will be described. Figure 6
FIG. 6 is a partial cross-sectional view showing a place where an adhered matter is found when a film is used in a resin sealing step. In FIG. 6, the lower mold 30 and the upper mold 31 facing each other are molds for resin sealing, and a film 32 is stretched between these molds. In the recess 33 provided in the lower die 30, a substrate 34 on which a chip (not shown) is mounted is placed. The film 32 along the cavity 35 provided in the upper mold 31 in a state where the lower mold 30 and the upper mold 31 are clamped.
In a space surrounded by the upper surface of the substrate 34, that is, a cavity in a narrow sense, a molten resin (not shown) is pressed and injected to cure. As a result, the cured resin 36 is formed. The film 32 is supplied between the molds by the supply roll 37 and the winding roll 38, and is wound around the winding roll 38 after use. The package 39 after resin sealing is sucked and conveyed by a suction pad (not shown).

When a film is used in the resin encapsulation process, an adhering substance 41 may be found on the cavity surface 40 of the upper mold 31. It is considered that the deposit 41 is generated due to the following reasons. First, the substance eluted from the film 32 may adhere to the cavity surface 40. Next, the gas component contained in the heated molten resin may be condensed after passing through the film 32 through the micropores of the film 32 by being pressurized and then adhered to the cavity surface 40. These deposits 41 may reduce the releasability between the cavity surface 40 and the film 32. In addition, even if the film is not used in the resin sealing step, a part of the molten resin may adhere to the cavity surface 40 as a resin residue.

Further, there is a case where the deposit 42 is found on the upper surface of the substrate 34, and it is considered that the deposit 42 is generated due to the substance eluted from the film 32. Furthermore,
Adhesive matter 43 may be found on the lower surface of the substrate 34 before resin sealing, and the adhering matter 43 is caused by an adhesive layer of the adhesive tape when the substrate 34 is attached to an adhesive tape (not shown). It is thought that this occurs. These deposits 4
Nos. 2 and 43 reduce the appearance quality of the package 39, and may evaporate in the reflow process when the package 39 is mounted, which may adversely affect the atmosphere in the reflow apparatus. Further, when the bumps are formed on the electrodes (not shown) provided on the lower surface of the substrate 34, the deposits 43 may reduce the adhesion between the electrodes and the bumps.

In some cases, an adhering substance 44 is found on the mold surface of the recess 33 of the lower mold 30. This deposit 4
It is considered that No. 4 was formed by transferring the adhering matter 43 on the lower surface of the substrate 34, and there is a possibility that it will be transferred again to the clean substrate 34.

Further, in order to remove these deposits 41 to 44, for example, a step of interrupting the resin sealing step and physically cleaning the cavity surface 40 or the like with a brush or a resin sealing step. Separately, it is necessary to provide a step of cleaning the substrate 34 and the package 39. Therefore, when the chip is resin-sealed, there is a problem that the cavity surface 40 is physically damaged or the man-hour of the entire resin sealing is increased.

The present invention has been made in order to solve the above-mentioned problems, and is a component in the case of producing a molded product by resin molding, such as a resin molding die, a resin molding An object of the present invention is to provide a cleaning method and apparatus for removing deposits on insert members and molded products after resin molding.

[0011]

In order to solve the above-mentioned technical problems, a cleaning method according to the present invention is performed by molding a resin by injecting a molten resin into a cavity provided in a mold and curing the resin. A method of cleaning a constituent element in the case of manufacturing an article using an irradiation means, a step of bringing the constituent element and the irradiation means close to each other by a predetermined distance, and using an irradiation means by excimer ultraviolet light. And irradiating the constituents to remove deposits on the constituents.

According to this method, the constituent element is illuminated through a predetermined distance by excimer ultraviolet light having a single peak wavelength and large photon energy. The excimer ultraviolet light breaks the molecular bonds of the deposits, particularly organic substances, on the constituents, thus lowering the adhesion between the surface of the constituents and the deposits. Further, the active substances generated by excimer ultraviolet light mainly oxidize and decompose the deposits whose molecular bonds are broken. Therefore, the deposits can be removed from the surface of the component without physically damaging the component.

Further, the cleaning method according to the present invention is
In the above-described cleaning method, the constituent element is the mold surface of the mold, and the deposit is a substance adhered to the mold surface due to the molten resin.

According to this, on the die surface of the die, the molecular bond of the deposit adhered due to the molten resin is cut by excimer ultraviolet light. This reduces the adhesion between the deposit and the mold surface. Further, the active oxygen generated mainly by the excimer ultraviolet light oxidatively decomposes the deposit having the broken molecular bond, and the deposit can be removed from the mold surface.

Further, the cleaning method according to the present invention is
In the above-mentioned cleaning method, the component is the mold surface of the mold, and the adhered matter is a substance adhered to the mold surface due to the film stretched along the mold surface during resin molding. Characterize.

According to this, on the die surface of the die, the molecular bond of the deposit adhered due to the film is cut by the excimer ultraviolet light. This reduces the adhesion between the deposit and the mold surface. Further, the active oxygen generated mainly by the excimer ultraviolet light oxidatively decomposes the deposit having the broken molecular bond, and the deposit can be removed from the mold surface.

Further, the cleaning method according to the present invention is
In the above-described cleaning method, the component is an insert member integrally formed with the molded product by resin molding, and the deposit is caused by a film stretched along the surface of the insert member during resin molding. The substance adhered to the surface of the insert member or the substance adhered to the surface of the insert member by transferring the substance adhered to the mold surface of the mold.

According to this, on the surface of the insert member, the molecular bond of the adhered matter caused by the film or the adhered matter caused by the transfer of the substance adhered to the mold surface can be prevented by excimer ultraviolet light. Disconnect. This reduces the adhesion between the deposit and the surface of the insert member. Furthermore, the active oxygen generated mainly by the excimer ultraviolet light oxidizes and decomposes the deposit whose molecular bond has been cut, and this can be removed from the surface of the insert member.

Further, the cleaning method according to the present invention is
In the above-mentioned cleaning method, the step of optically evaluating the surface state of the constituent element, and based on the result of the evaluation, determine whether or not the constituent element is irradiated by the irradiation means, or the irradiation means determines the constituent element. And a step of determining an irradiation condition at the time of irradiation.

According to this, whether or not to irradiate the constituent element is determined or the irradiation condition is determined based on the result of optically evaluating the surface state of the constituent element. Therefore, by irradiating the constituent elements under appropriate irradiation conditions as needed, it is possible to improve the work efficiency in cleaning the constituent elements.

Further, the cleaning method according to the present invention is
The above-described cleaning method is characterized by including a step of supplying a gas having a property of suppressing the attenuation of excimer ultraviolet light in the vicinity of the irradiated surface of the constituent element.

According to this, the attenuation of the excimer ultraviolet light is suppressed by the gas supplied in the vicinity of the irradiated surface of the constituent element. As a result, the ability to cut the molecular bond of the deposit by the excimer ultraviolet light and the ability to generate active oxygen are maintained. Therefore, it is possible to maintain the ability to cleave the molecular bond of the deposit and to oxidize and decompose the cleaved deposit, that is, the ability to clean the components. In addition, even when the constituent elements have irregularities, since the excimer ultraviolet light is suppressed from being attenuated in the concave portion where the irradiation distance is long, it is possible to effectively remove the deposit in the concave portion.

Further, the cleaning method according to the present invention is
In the cleaning method described above, in the supplying step,
It is characterized in that the supply of gas is controlled so that the concentration of the gas becomes an optimum concentration for cleaning the component.

According to this, it is possible to suppress the phenomenon that the generation efficiency of active oxygen and the like decreases due to the increase of the gas concentration. Therefore, the constituent elements can be cleaned under the optimum conditions of suppressing the attenuation of excimer ultraviolet light and maintaining the generation efficiency of active oxygen and the like.

Further, the cleaning method according to the present invention is
The above-described cleaning method is characterized by including a step of heating the gas.

According to this, it is possible to suppress a decrease in temperature on the irradiated surface of the constituent element. Therefore, it is unlikely that the oxidative decomposition of the adhered matter is inhibited by the temperature decrease, and therefore the ability to oxidatively decompose and remove the adhered matter on the irradiated surface, that is, the ability to clean the constituent elements is maintained. You can

Further, the cleaning device according to the present invention is
A cleaning device for cleaning constituent elements when a molded product is manufactured by injecting a molten resin into a cavity provided in a mold and curing the resin, the irradiation device irradiating an excimer ultraviolet light, and an excimer. And a gas supply means for supplying a gas having a property of suppressing attenuation of ultraviolet light in the vicinity of the irradiated surface of the constituent element, and the irradiation means is a constituent element in a state where the concentration of the gas is increased in the vicinity of the irradiated surface By irradiating the excimer ultraviolet light with respect to, the deposits on the constituent elements are removed.

According to this, the constituent element is illuminated through a predetermined distance by excimer ultraviolet light having a single peak wavelength and large photon energy. The excimer ultraviolet light breaks the molecular bonds of the deposits, particularly organic substances, on the constituents, and thus the adhesion between the surface of the constituents and the deposits is reduced. Further, the active oxygen generated by the excimer ultraviolet light oxidizes and decomposes the deposit having the molecular bond cut. Thus, the deposit is removed from the surface of the component without the component being physically damaged. Moreover, the attenuation of excimer ultraviolet light is suppressed by the gas supplied in the vicinity of the irradiated surface of the constituent elements. As a result, the ability to break the molecular bond of the deposit and the ability to generate active oxygen by excimer ultraviolet light are maintained. Therefore, the ability to cleave the molecular bonds of the deposit and oxidatively decompose the cleaved deposit, ie, the ability to clean the components, is maintained. In addition, even if the constituent elements have irregularities, attenuation of excimer ultraviolet light is suppressed in the concave portion, which is a portion where the irradiation distance is long, so that the deposits in the concave portion are effectively removed.

Further, the cleaning device according to the present invention is
The above-mentioned cleaning device is characterized by including heating means for heating the gas, and the gas supply means supplies the heated gas.

According to this, it is possible to suppress the temperature drop on the irradiated surface of the constituent element. Therefore, it is unlikely that the oxidative decomposition of the deposits is inhibited by the temperature decrease, and therefore the ability to oxidatively decompose and remove the deposits on the irradiated surface, that is, the ability to clean the constituent elements is maintained. .

[0031]

(First Embodiment) First Embodiment of the Present Invention
Embodiments will be described with reference to FIGS. 1 and 2. Here, as an example of resin molding, a component molded at an appropriate position in a molded product, that is, a chip mounted on a substrate as an insert member is resin-sealed to manufacture a package such as an LSI as a molded product. A case will be described. Further, a mold will be described as an example of a constituent element in the case of manufacturing a molded product. FIG. 1 is a schematic front view showing a state in which the cleaning device according to the present embodiment is incorporated in a resin sealing device. FIG. 2 is a schematic side view showing a state in which the cleaning device of FIG. 1 irradiates the mold surface with excimer ultraviolet light.

In FIG. 1, a mold unit 1 is a unit for sealing resin, and a standby unit 2 is a unit connected to the mold unit 1 for a lamp unit (irradiation means) described later to stand by. In the mold unit 1, the upper mold 3 and the lower mold 4 are resin-sealing dies provided to face each other. The upper die 3 is a fixed die, and is provided with a runner 6 and a cavity 7 which are in communication with the cull 5 and the cull 5, respectively. The cull 5, the runner 6, and the cavity 7 together form a resin flow portion 8 on the side of the upper mold 3.
The lower mold 4 is a movable mold, and a pot 9 is provided at a position facing the cull 5 and a cavity 10 is provided at a position facing the cavity 7. The pot 9 and the cavity 10 together constitute a resin flow part 11 on the side of the lower mold 4.

The nozzle 12 is connected to a gas supply source (neither is shown) via a valve, and injects a predetermined gas near the die surfaces of the upper die 3 and the lower die 4 as necessary. It is a gas supply means to be supplied. The supplied gas is a gas other than oxygen and has a property of suppressing attenuation of excimer ultraviolet light, for example, nitrogen gas. The exhaust pipe 13 is an exhaust unit that is connected to a suction pump (neither is shown) via a valve and discharges the gas in the mold unit 1 to the outside.

The lamp unit 14 is an irradiation means for irradiating the surface to be irradiated, that is, the mold surfaces of the upper mold 3 and the lower mold 4, with excimer ultraviolet light through a predetermined distance. The excimer lamp 15 is mounted inside the lamp unit 14, and is a lamp that generates excimer ultraviolet light having a wavelength of 172 nm by dielectric barrier discharge using, for example, xenon (Xe) as a discharge gas. Translucent window 16
Is an irradiation window provided on both upper and lower surfaces of the lamp unit 14 and made of, for example, synthetic quartz glass. From the viewpoint of preventing a decrease in the irradiance of excimer ultraviolet light on the mold surface, it is preferable that the distance between the transparent window 16 and each mold surface is as small as possible. The rail 17 is the lamp unit 1
4 is a moving means for moving, and is a motor (not shown)
The lamp unit 14 driven by moves horizontally along the rail 17.

The operation of the cleaning device according to this embodiment will be described with reference to FIGS. 1 and 2. Upper mold 3 and lower mold 4 which have been heated to a predetermined molding temperature (for example, 180 ° C.) in advance.
By performing resin sealing, for example, the following deposits mainly made of organic substances may be attached to the mold surfaces of the resin flow parts 8 and 11 of. First, when the film is not used in the resin encapsulation step, a component caused by the molten resin, that is, a resin residue made of a part of the molten resin, may adhere to the mold surface. The molten resin referred to here includes both thermosetting resin and thermoplastic resin. Secondly, when a film is used, a component derived from the film, that is, a substance eluted from the film may adhere to the mold surface. Thirdly, when a film is used, a component derived from the molten resin, that is, a gas component contained in the heated molten resin is permeated through the film through the micropores of the film when pressurized. After that, it may be condensed and adhere to the mold surface.

In the present embodiment, first, in FIG. 1, the lamp unit 14 is moved from the standby unit 2 along the rail 17 so that the excimer ultraviolet light passing through the light-transmitting window 16 becomes the upper mold 3 and the lower mold 4. It is stopped at a predetermined position where the desired area of the mold surface is uniformly irradiated. In addition, the nozzle 12
Then, nitrogen gas is supplied near the mold surfaces of the upper mold 3 and the lower mold 4. As a result, the atmosphere near the mold surface has a low oxygen concentration.

Next, a predetermined high frequency voltage is applied to the excimer lamp 15. As a result, as shown in FIG. 2, the excimer lamp 15 has a predetermined center wavelength (for example, 172n when Xe is used as the discharge gas).
Excimer UV light 18 having m) is generated. The lamp unit 14 receives the excimer ultraviolet light 1 through the transparent window 16.
8 is applied to the mold surfaces of the upper mold 3 and the lower mold 4, that is, the mold surfaces in the resin flowing parts 8 and 11 shown in FIG. This excimer ultraviolet light 18 is vacuum ultraviolet light (VUV).
m Ultra Violet), which has a wavelength in an extremely narrow range around the center wavelength, that is, a single peak wavelength, and has a characteristic that the energy of photons is large.

The irradiation conditions for irradiating the excimer ultraviolet light 18 are defined as follows. First, the energy of the excimer ultraviolet light 18 does not peel off a layer such as a plating layer formed in advance on the mold surface for the purpose of protecting the mold surface and ensuring releasability when the mold surface is irradiated for a certain period of time. It is set to be a value of degree. Further, this energy is set to a value at which the deposit on the mold surface can be sufficiently decomposed and removed when the mold surface is irradiated for a certain period of time. Therefore, by irradiating the mold surface with the excimer ultraviolet light 18 having such energy,
It is possible to sufficiently decompose and remove deposits on the mold surface without peeling off the plating layer or the like. Then, the cleaning of the mold surface is completed by irradiating the mold surface with the excimer ultraviolet light 18 for a certain period of time.

The action of the excimer ultraviolet light 18 will be described in detail as follows. First, the energy of the excimer ultraviolet light 18 breaks the molecular bonds of the deposits, especially organic substances, on the mold surface. This reduces the adhesion between the mold surface and the deposit. Along with that, excimer ultraviolet light 1
By the energy of 8, ozone (O ₃ ) and active oxygen are generated from oxygen existing in the mold unit 1.
Next, among these, mainly active oxygen acts on the adhering substance whose molecular bond is broken, and the adhering substance is oxidatively decomposed and volatilized. As a result, the deposits on the mold surface are decomposed and removed. The gas in the mold unit 1 contains ozone which is harmful to the human body and deteriorates and corrodes metallic materials, polymeric materials and the like. Therefore, this gas is discharged to the outside of the resin sealing device by the exhaust pipe 13.

Further, according to this embodiment, the vicinity of the mold surface,
That is, the space between the light-transmitting window 16 and the mold surface has a low oxygen concentration atmosphere by supplying the nitrogen gas having the property of suppressing the attenuation of the excimer ultraviolet light 18. This suppresses the attenuation of the excimer ultraviolet light 18 caused by oxygen. Therefore, the ability to break the molecular bond of the deposit by the excimer ultraviolet light 18 and the ability to generate active oxygen are maintained. This makes it possible to maintain the ability to cut the molecular bond of the deposit and to oxidatively decompose the deposit with the broken molecular bond, that is, the ability to clean the constituent elements. In addition, even in the case where the constituent elements have irregularities, the attenuation of the excimer ultraviolet light 18 is suppressed in the concave portion that is the portion where the irradiation distance is long, for example, in the cavities 7 and 10. Therefore, it is possible to effectively remove the deposits in the recess.

Next, the supply of nitrogen gas from the nozzle 12 is stopped and the lamp unit 14 is moved along the rail 17 as shown in FIG.
Move to the standby unit 2 shown in. After that,
A substrate having chips mounted thereon is placed on the lower mold 4, the upper mold 3 and the lower mold 4 are clamped, and molten resin is put into the cavities 7 and 10 from the pot 9 through the cull 5 and the runner 6 in sequence. (Not shown) is injected and cured to form a cured resin.

Next, the upper mold 3 and the lower mold 4 are opened, and a molded product (not shown) composed of the substrate and the cured resin is taken out. This completes the resin sealing of the chip.

Next, the lamp unit 14 is again moved from the standby unit 2 to a predetermined position, and nitrogen gas is supplied to the vicinity of the mold surfaces of the upper mold 3 and the lower mold 4 by the nozzle 12. Then, as shown in FIG.
Irradiates the mold surface of the upper mold 3 and the lower mold 4 with excimer ultraviolet light 18. Thereafter, cleaning of the mold surface and resin sealing of the chip are repeated.

As described above, according to the present embodiment, the excimer ultraviolet light 18 having a single peak wavelength and large photon energy is provided between the resin encapsulation of the chip.
The mold surfaces of the upper mold 3 and the lower mold 4 are irradiated, and the mold surfaces are cleaned by a non-contact method. As a result, it is not necessary to interrupt the resin sealing and perform cleaning with a brush or the like as a separate step, so that the resin sealing can be continuously performed without physically damaging the mold surface. Further, by supplying the nitrogen gas, the attenuation of the excimer ultraviolet light 18 caused by oxygen is suppressed. Therefore, the ability to cut the molecular bond of the deposit and the ability to generate active oxygen are improved, and even when the mold surface has irregularities, the deposit in the recess, which is the portion where the irradiation distance becomes long, is removed. , Can be effectively decomposed and removed.

In the description of this embodiment, after the lamp unit 14 is stopped at a predetermined position, the excimer lamp 15 is turned on and the excimer ultraviolet light 18 is emitted. Instead of this, the lamp unit 14 may be moved while the excimer lamp 15 is turned on while irradiating the mold surface with the excimer ultraviolet light 18. In this case, it is preferable to determine the irradiation conditions for the mold surface in consideration of not only the energy of the excimer ultraviolet light 18 but also the moving speed of the lamp unit 14. In addition, perpendicular to the paper surface of FIG.
It is preferable to provide one or more excimer lamps 15.

In the description of this embodiment, the mold surface is irradiated every time the resin is sealed. Not limited to this,
The relationship between the number of consecutive resin encapsulations, the state of the mold surface, and the quality of the molded product, that is, the package, etc. is evaluated in advance, and the resin encapsulation is performed a predetermined number of times according to the evaluation. The mold surface may be irradiated after irradiation. As a result, the lamp unit 14 is operated a minimum number of times, so that the work efficiency of resin sealing is improved.

By supplying nitrogen gas,
The attenuation of the excimer ultraviolet light 18 caused by oxygen is suppressed. However, when the concentration of nitrogen gas is high, the concentration of oxygen gas is low, and as a result, ozone and active oxygen are less likely to be generated. Therefore, the cleaning efficiency may decrease. Therefore, the optimum concentration of nitrogen gas according to the irradiance of the excimer ultraviolet light 18 is experimentally investigated in advance, and the supply of nitrogen gas is controlled with the goal of achieving the optimum concentration of nitrogen gas. Is preferred. Thereby, the mold surface can be cleaned under the optimum conditions of the irradiance of the excimer ultraviolet light 18 and the optimum nitrogen gas concentration according to the irradiance.

(Second Embodiment) A second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a schematic front view showing a state in which the cleaning device according to the present embodiment is incorporated in the resin sealing device. A feature of this embodiment is that the cleaning device incorporates an evaluation unit that optically detects and evaluates the state of the mold surface to determine the necessity of irradiation. In FIG. 3, the sensor 19 irradiates the irradiation light 20 in both the upper and lower directions, detects the reflected light 21 which is the light reflected by the mold surface, and the ratio of the reflected light 21 to the irradiation light 20, That is, it is an evaluation means for calculating the reflectance and comparing the calculated value with a predetermined reference value. The sensor 19 may be, for example, an optical non-contact sensor that uses visible light, infrared rays, a laser, or the like.

The operation of the cleaning device according to this embodiment will be described with reference to FIG. First, similarly to the first embodiment, the lamp unit 14 is moved to move the nozzle 1
Nitrogen gas is supplied to the vicinity of the mold surfaces of the upper mold 3 and the lower mold 4 by 2.

Next, when the sensor 19 reaches above the cavities 7 and 10, the sensor 19 irradiates the irradiation light 20 in both upper and lower directions, and the irradiation light 20 is reflected by the mold surfaces of the cavities 7 and 10. The reflected light 21, which is the reflected light, is detected. Further, the sensor 19 calculates the reflectance and compares the calculated value with a predetermined reference value. Here, as the reference value,
For example, the reflectance when the mold is unused, that is,
The reflectance in the initial state of the mold can be used. The detection of the reflected light 21, the calculation of the reflectance, and the comparison with the reference value may be performed separately in the sensor body and the calculation unit.

Here, when the calculated value of the reflectance is, for example, the reference value or more, the sensor 19 judges that the state of the mold surface has not changed so much compared with the initial state, and the excimer lamp. No signal is generated to turn on 15. Then, after the lamp unit 14 returns to the standby unit 2 without irradiating the mold surface, the upper mold 3 and the lower mold 4 are clamped, and normal resin sealing is performed. On the other hand, when the calculated value of the reflectance is lower than the reference value, the sensor 19 determines that the state of the mold surface is worse than that in the initial state, that is, a considerable amount of the deposit is attached to the mold surface. , Generates a signal for turning on the excimer lamp 15. And the lamp unit 14
Irradiates the mold surface under predetermined irradiation conditions according to the signal, and then returns to the standby unit 2. After that, normal resin sealing is performed.

As described above, according to this embodiment, whether or not to irradiate the mold surface is determined based on the result of optically evaluating the state of the mold surface. Therefore, the same effect as that of the first embodiment can be obtained, and the mold surface is cleaned by irradiating the mold surface as necessary, so that the work efficiency of resin sealing is further improved.

In the description of this embodiment, the mold surface is irradiated while the lamp unit 14 is stationary. Not limited to this, the mold surface may be irradiated while the lamp unit 14 is moving.

Further, based on the evaluation result of the sensor 19, it was determined whether or not the mold surface should be irradiated and cleaned. Not limited to this, based on the evaluation result by the sensor 19, for example, irradiation conditions such as irradiation distance, irradiance, irradiation time when irradiation is performed in a stationary state, and moving speed when irradiation is performed while moving may be determined. it can. That is, when it is evaluated that the mold surface is significantly deteriorated from the initial state, for example, by increasing the irradiation time, it is possible to reliably remove the deposits from the mold surface.

Further, when the sensor 19 evaluates the state of the mold surface, the reflectance is calculated at a plurality of points, and the reflectance is evaluated based on the value indicating the most changed state of the mold surface. Alternatively, the evaluation may be performed based on their average value.
Further, even in a portion where the state of the mold surface is likely to change, for example, in a portion near each runner 6 in each of the cavities 7 and 10, the reflectance is pinpointed to evaluate the state of the mold surface. Good.

Further, the sensor 19 calculates reflectance and compares it with a reference value. However, the condition of the mold surface may be evaluated based on the image data of a certain area that is captured. For example, the sensor 19 is C
It is also possible to use a type having a CD camera and an image processing unit, binarize a photographed image with a predetermined threshold value, and compare the area of a high density portion with a reference value, for example.

(Third Embodiment) A third embodiment of the present invention will be described with reference to FIG. FIG. 4 is a schematic front view showing a state in which the cleaning device according to the present embodiment is incorporated in the resin sealing device to perform cleaning.
A feature of this embodiment is that the cleaning device is provided with a means for heating and supplying a predetermined gas.

In FIG. 4, the nozzle 22 is connected to a gas supply source 25 via a gas pipe 23 and a valve 24, and on both upper and lower surfaces of the lamp unit 14, for example, from the corners to the center of those surfaces. It is a gas supply means provided so as to face. The nozzle 22 is provided with excimer ultraviolet light 1 in the vicinity of the mold surfaces of the upper mold 3 and the lower mold 4 heated to a molding temperature (for example, 180 ° C.) as a mold temperature.
A gas having a property of suppressing the attenuation of 8 such as nitrogen gas 26 is supplied. The heater 27 is a heating unit that is attached to a portion of the gas pipe 23 between the gas supply source 25 and the valve 24 and heats the nitrogen gas 26 to a predetermined temperature (for example, a temperature substantially equal to the mold temperature). . The cooling liquid pipe 28 is provided in the lamp unit 14 for the transparent window 16.
It is a cooling means that is provided in the periphery of and cools the transparent window 16 to a predetermined temperature (for example, 120 ° C.) or less by circulating a cooling liquid such as water.

If it is possible to heat the supplied nitrogen gas 26 to a predetermined temperature, the heater 27 can be attached to each portion of the gas pipe 23 near each nozzle 22. In this case, the valve 24
At a portion closer to each nozzle 22 than the heater 27,
You can also attach each. Further, instead of the cooling liquid pipe 28, a cooling means such as a Peltier element may be provided near the transparent window 16.

According to this embodiment, the following effects can be obtained. First, since the mold surface is kept at a predetermined temperature, the effect of cleaning the mold surface is maintained for the following reasons. That is, the nitrogen gas 26 heated by the heater 27 to a predetermined temperature substantially equal to the mold temperature is supplied near the mold surfaces of the upper mold 3 and the lower mold 4. Thereby, the temperature of the mold surface is maintained at a predetermined mold temperature. Here, the effect of the active oxygen generated by the excimer ultraviolet light 18 to oxidatively decompose the deposit and clean the mold surface is suppressed when the temperature of the mold surface is lowered. Therefore, by maintaining the mold surface at a predetermined mold temperature, the effect of cleaning the mold surface is maintained. Secondly, the cooling liquid pipe 28 cools the translucent window 16, whereby the irradiance of the excimer ultraviolet light 18 on the mold surface is maintained for the following reason.
That is, since the translucent window 16 made of synthetic quartz glass has a property that the translucency decreases when the temperature rises, the translucency is maintained by cooling the translucent window 16. Therefore, since the irradiance of the excimer ultraviolet light 18 on the mold surface is maintained, the effect of cleaning the mold surface is maintained.

In this embodiment, the molding temperature (180
In the vicinity of the mold surface of the mold heated to (° C.), nitrogen gas 26 having a temperature substantially equal to the mold temperature was supplied. The present invention is not limited to this, and the mold may be heated to the optimum temperature for cleaning within the range permitted by the apparatus, the process, and the like.
For example, the mold can be heated at a temperature higher than the molding temperature to improve the cleaning efficiency. Further, it is preferable to adjust the temperature of the nitrogen gas 26 according to the mold temperature. Further, the nitrogen gas 26 may be supplied at room temperature when the adhesion strength of the deposit is low, the mold temperature is high to some extent, or the flow rate of the nitrogen gas 26 may be low.

In each of the first to third embodiments described so far, the nozzle 12 and the lamp unit 14 are provided.
(And the sensor 19 and the nozzle 22) may be attached to a transfer unit that carries in a substrate and carries out a molded product, that is, a loader / unloader. As a result, both before loading the substrate and after unloading the molded product,
The mold surface can be easily cleaned. Therefore, the mold surface can be cleaned with an even shorter cycle and high frequency.

Although the mold surfaces of both the upper mold 3 and the lower mold 4 are cleaned, the invention is not limited to this, and only one of the mold surfaces may be cleaned if necessary.

In addition, the nozzle 12 and the lamp unit 14
(And the sensor 19 and the nozzle 22) are provided for one mold surface, a gas is supplied to this mold surface, the excimer ultraviolet light 18 is irradiated, and the state of the mold surface is evaluated. Good. In this case, if necessary, the nozzle 1
2, lamp unit 14 (and sensor 19, nozzle 2
2) may be inverted and used.

When the film is used, the film is retracted horizontally or vertically from between the lamp unit 14 and the die to be irradiated in consideration of absorption of the excimer ultraviolet light 18 by the film. It is preferable to irradiate the excimer ultraviolet light 18 in this state. Further, when exchanging the film, it is possible to irradiate the mold with the excimer ultraviolet light 18 to regularly clean the mold.

(Fourth Embodiment) A fourth embodiment of the present invention will be described with reference to FIG. FIG. 5 is a schematic front view showing a state in which the cleaning device according to the present embodiment irradiates the package. In FIG. 5, the resin-sealed package 39 is fixed by being sucked by the suction pads 29, which are transport mechanisms, respectively. Each suction pad 29 conveys each package 39 right above the lamp unit 14 and stops. In this state, the lamp unit 14 irradiates the lower surface of the substrate 34, which is a part of the package 39, with the excimer ultraviolet light 18. As a result, the deposit 43 on the lower surface of the substrate 34
Is decomposed and removed.

According to the present embodiment, it is possible to disassemble and remove the deposits on the package 39 after resin sealing by utilizing a part of the carrying step after resin sealing. Therefore, since it is not necessary to separately provide a cleaning step, the package 39 can be cleaned without increasing the total number of steps when the chip is sealed with resin.

In the description of this embodiment, the package 39 after resin encapsulation, that is, the molded product is irradiated with the excimer ultraviolet light 18. More specifically, the lower surface of the substrate 34 as a part of the package 39 was irradiated with the excimer ultraviolet light 18. The present invention is not limited to this, and it is also possible to irradiate another object depending on the condition of the attached matter. For example, the substrate 34 as a single body before resin sealing or the substrate 34 with a chip mounted may be irradiated. Further, the upper surface of the substrate 34 or the cured resin 36 as a part of the package may be irradiated. In other words, the object to be irradiated with the excimer ultraviolet light 18 may be any constituent element when the chip is resin-sealed using the mold. As a typical example, the mold surface of the mold described in the above embodiments,
In addition to the substrate before resin sealing and the package after resin sealing, a jig for adsorbing the substrate or the package, a jig for conveying, and a tray for storing may be mentioned.

Further, in this embodiment, the sensor 19 shown in FIG.
May be used to optically evaluate the condition of the package 39, that is, the molded article. In this case, it is possible to judge the necessity of cleaning and determine the irradiation condition based on the evaluation result.

In each of the above-mentioned embodiments, a gas consisting of xenon (Xe) alone was used as the discharge gas to generate excimer ultraviolet light having a wavelength of 172 nm. Not limited to this, it is also possible to use a discharge gas containing at least one of the elements such as F, Ar, Kr, and Xe. Also in these cases, excimer ultraviolet light having a single peak wavelength other than the wavelength of 172 nm, particularly a single peak wavelength shorter than the wavelength of 172 nm, can be obtained.

The following substances have been mentioned as the deposits on the mold surface. That is, a resin residue consisting of a part of the molten resin, a substance eluted from the film, a gas component contained in the molten resin condensed after passing through the film through the micropores of the film, and an adhesive tape It is a substance caused by layers and the like. The deposits on the mold surface and the like are not limited to these, and include fats and oils components adhered to the mold surface and the like due to an operator's careless touch, substances attached by volatilization of the lubricating oil of the mechanism portion, and the like.

Up to this point, when cleaning the die surface of the die, the lamp unit 14 was moved to above the die. The present invention is not limited to this, and the mold removed from the resin sealing device may be moved to below (or above) the lamp unit 14. In this case, it is preferable to preheat the mold to the optimum temperature for cleaning within the range permitted by the apparatus and process.

Further, up to this point, as the mold, the mold used for sealing the chip with the resin has been described as an example.
The present invention is not limited to this, and the present invention can be applied to other resin molding dies and constituent elements in resin molding.

The present invention is not limited to the above-mentioned embodiments, and can be arbitrarily and appropriately changed and selected as necessary within the scope of the gist of the present invention. It is a thing.

[0075]

EFFECTS OF THE INVENTION According to the present invention, the molecular bond of the deposit in the constituent element is broken by excimer ultraviolet light having a single peak wavelength and large photon energy. Furthermore, the active oxygen generated by the excimer ultraviolet light oxidizes and decomposes the deposit whose molecular bond has been cut. Therefore, the deposits can be removed from the surface of the component without physically damaging the component. Further, since the gas supplied in the vicinity of the surface to be irradiated in the constituent elements suppresses the attenuation of excimer ultraviolet light, the ability to cut the molecular bond of the deposit by excimer ultraviolet light and the ability to generate active oxygen are maintained. . Therefore, the ability to cleave the molecular bonds of the deposit and the ability to oxidatively decompose the cleaved molecular bond, ie, the ability to clean the components, can be maintained. In addition, even when the component has unevenness, it is possible to effectively remove the deposits in the recessed portion where the irradiation distance is long. In addition, it is unlikely that the oxidative decomposition of the deposits is hindered by the temperature decrease on the irradiated surface of the component. Therefore, the ability to oxidatively decompose and remove the deposits on the irradiated surface, that is, the ability to clean the constituent elements can be maintained. INDUSTRIAL APPLICABILITY As described above, the present invention provides a method and apparatus for cleaning a component in resin molding, which cleans a component in the case of producing a molded product by resin molding without causing physical damage. That is, it has an excellent practical effect.

[Brief description of drawings]

FIG. 1 is a schematic front view showing a state in which a cleaning device according to a first embodiment of the present invention is incorporated in a resin sealing device.

FIG. 2 is a schematic side view showing a state in which the cleaning device shown in FIG. 1 irradiates a mold surface with excimer ultraviolet light.

FIG. 3 is a schematic front view showing a state in which a cleaning device according to a second embodiment of the present invention is incorporated in a resin sealing device.

FIG. 4 is a schematic front view showing a state in which a cleaning device according to a third embodiment of the present invention is incorporated in a resin sealing device to perform cleaning.

FIG. 5 is a schematic front view showing a state in which a cleaning device according to a fourth exemplary embodiment of the present invention irradiates a package.

FIG. 6 is a partial cross-sectional view showing a place where a deposit is found when a film is used in a resin sealing step.

[Explanation of symbols]

1 Mold unit 2 Standby unit 3 Upper mold (mold) 4 Lower mold (mold) 5 cal 6 runners 7, 10 cavities 8, 11 Resin flow section 9 pots 12 nozzles (gas supply means) 13 Exhaust pipe 14 Lamp unit (irradiation means) 15 excimer lamp 16 translucent windows 17 rails 18 Excimer UV light 19 sensors 20 irradiation light 21 reflected light 22 nozzles (gas supply means) 23 Gas piping 24 valves 25 gas supply source 26 Nitrogen gas (gas) 27 Heater (heating means) 28 Piping for cooling liquid 29 Adsorption pad 30 Lower mold 31 Upper mold 32 films 33 recess 34 substrate 35 cavities 36 Cured resin 37 supply rolls 38 winding roll 39 packages (molded products) 40 Cavity surface (mold surface) 41-44 Adhesion

Continued front page    (72) Inventor Shigeru Hirata             5 Toamigamicho, Minami-ku, Kyoto-shi, Kyoto Prefecture             Towa Co., Ltd. (72) Inventor Atsushi Hirota             5 Toamigamicho, Minami-ku, Kyoto-shi, Kyoto Prefecture             Towa Co., Ltd. F term (reference) 4F202 AH37 AM10 CA12 CB01 CB17                       CS02

Claims (10)

[Claims] 1. A cleaning method for cleaning components using irradiation means when resin molding is performed by injecting a molten resin into a cavity provided in a mold and curing the resin to produce a molded product. A step of bringing the constituent element and the irradiation means close to each other by a predetermined distance, and a step of irradiating the constituent element with excimer ultraviolet light using the irradiation means to remove deposits on the constituent element. A cleaning method characterized by being provided. 2. The cleaning method according to claim 1, wherein the constituent element is a mold surface of the mold, and the deposit is a substance adhered to the mold surface due to the molten resin. The characteristic cleaning method. 3. The cleaning method according to claim 1, wherein the constituent element is a mold surface of the mold, and the deposit is a film stretched along the mold surface during the resin molding. A cleaning method characterized in that the substance is a substance that adheres to the mold surface. 4. The cleaning method according to claim 1, wherein the constituent element is an insert member integrally formed with the molded product by the resin molding, and the deposit is the insert when the resin molding is performed. Attached to the surface of the insert member by transferring the substance attached to the surface of the insert member due to the film stretched along the surface of the member or the substance attached to the mold surface of the mold A cleaning method characterized in that it is a substance. 5. The cleaning method according to any one of claims 1 to 4, wherein the step of optically evaluating the surface state of the constituent element, and the irradiation unit based on a result of the evaluation. And a step of deciding whether or not to irradiate the constituent element, or deciding an irradiation condition when the irradiating means irradiates the constituent element. 6. The cleaning method according to claim 1, wherein a gas having a property of suppressing attenuation of the excimer ultraviolet light is supplied in the vicinity of a surface to be irradiated in the constituent element. A cleaning method comprising: 7. The cleaning method according to claim 6, wherein in the supplying step, the supply of the gas is controlled so that the concentration of the gas becomes an optimum concentration for cleaning the constituent element. The characteristic cleaning method. 8. The cleaning method according to claim 6, further comprising a step of heating the gas. 9. A cleaning device for cleaning constituent elements when a molded product is manufactured by molding a resin by injecting a molten resin into a cavity provided in a mold and curing the resin, and irradiating excimer ultraviolet light. Irradiation means and a gas supply means for supplying a gas having a property of suppressing the attenuation of the excimer ultraviolet light in the vicinity of the irradiated surface of the constituent element, and the concentration of the gas in the vicinity of the irradiated surface is A cleaning device characterized in that the irradiation means irradiates the constituent element with the excimer ultraviolet light in an increased state to remove deposits on the constituent element. 10. The cleaning device according to claim 9, further comprising: a heating unit configured to heat the gas, wherein the gas supply unit supplies the heated gas.