JP2006324494A - Coater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coater and a coating method coating a base material with which a semiconductor chip such as a semiconductor element, a solid-state image sensing element or the like is bonded, with a coating liquid such as an adhesive in a stable quantity, and capable of preventing the deterioration of a productivity. <P>SOLUTION: The coater has: a nozzle with a discharging section discharging the coating liquid; and a two-dimensional information acquiring means for acquiring a two-dimensional information related to the shape of the coating liquid from the horizontal direction of the discharging section, under the state in which the coating liquid is held to the discharging section before the base material is coated with the coating liquid. The coater further has an arithmetic section computing the quantity of the coating liquid coated on the basis of the two-dimensional information acquired by the two-dimensional information acquiring means. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a coating apparatus, and more particularly to a coating apparatus suitable for applying an adhesive in a die bonding process for bonding a semiconductor element or a solid-state imaging element to a package, a lead frame, or a substrate.

  Conventionally, when a semiconductor element is bonded to a semiconductor substrate or a solid-state imaging element is bonded to a package container, an adhesive is applied to these substrates from an adhesive application device, and then the semiconductor element and the solid-state imaging element are assembled to these substrates. The process is being performed.

  When attaching a semiconductor element or a solid-state image sensor (hereinafter collectively referred to as a semiconductor chip) to the bottom of a ceramic or resin package container, first, a solid-state image sensor called die attach at the bottom of the package container is used. Adhesive is applied to the mounting position using an applicator. Examples of the coating apparatus include those shown in Patent Documents 1 and 2 below.

  When attaching an adhesive to the bottom of a package container, if the amount of adhesive applied to the bottom by an applicator is not appropriate, the semiconductor chip to be bonded may be slightly tilted or fixed. It may shift and may cause quality degradation. Therefore, as in Patent Documents 1 and 2, the application amount of the adhesive is optimized.

JP 2001-338938 A JP 2002-280399 A

  FIG. 6 is a diagram illustrating a conventional coating system. Conventionally, the coating apparatus 100 causes a base material W such as a package container or a lead frame transported by a transport member to eject an adhesive P such as silver paste from a discharge portion of a nozzle 102 in the coating member 103, thereby causing the base material W to be discharged. The adhesive P is applied to the surface. Then, after applying the adhesive P to the substrate W, the semiconductor chip T is held by the assembly member 107 and adhered to the substrate W.

  In Patent Document 1, after the adhesive P is applied to the substrate W, the adhesive P applied on the substrate W is monitored from the upper surface of the substrate W by the image recognition unit 105, and the operator applies the application time. The application conditions such as can be adjusted. However, the applied adhesive P has a problem that the shape does not become constant due to stringing or the like, and the measured application area does not accurately match the actual application amount. Hereinafter, a specific description will be given with reference to FIG.

  FIG. 7 is a diagram illustrating the state of the adhesive applied to the substrate. FIGS. 7A and 7B both show a state where the adhesive P is applied to the base material W, and the upper side of each figure is a top view of the base material W viewed from above (upper side in FIG. 6). The lower part of each figure represents the side view which looked at the base material W from the side (front of FIG. 6). In the top views of FIGS. 7A and 7B, the areas of the adhesive P applied to the substrate W are both equal. For this reason, when the top view is seen from the base material W like the said patent document 1, it is recognized that the application quantity of the adhesive agent P is both equal. However, as shown in the side views of FIGS. 7A and 7B, when the thicknesses h1 and h2 to which the adhesive P is applied are different, the application amount of the adhesive P is different. Patent Document 1 is based on the premise that the shape of the adhesive P is constant. However, when the applied adhesive P is viscous, such as silver paste, the coating liquid applied by stringing or the like is used. The shape does not become constant, and as shown in FIGS. 7A and 7B, there is a concern that an error may occur when the application amount is measured by the area of the adhesive P recognized from above the substrate W.

  Moreover, in the evaluation method of patent document 2, as shown in FIG. 8, the paste adhesive P apply | coated to the island of base materials W, such as a lead frame which should adhere | attach a semiconductor chip, is applied to an application volume laser displacement measuring device etc. Measurement is performed using a means, the result is fed back to the coating device, and the coating amount is adjusted to optimize the coating amount of the adhesive P. However, since the shape of the adhesive P applied as described above does not become constant due to stringing or the like, in order to measure the volume of the applied adhesive P with high accuracy, a coating liquid using a laser displacement meter is used. It is necessary to increase the number of measurement points S by minimizing the scanning pitch between the measurement points S of the surface height, thereby increasing the measurement accuracy. Then, the time required for measurement and volume measurement becomes enormous, and it is inevitable that productivity is lowered.

  The present invention has been made in view of the above circumstances, and its purpose is to apply a stable amount of a coating solution such as an adhesive to a base material to which a semiconductor chip such as a semiconductor element or a solid-state imaging element is bonded. An object of the present invention is to provide a coating apparatus and a coating method capable of preventing the deterioration of the property.

  The above-mentioned object of the present invention is a coating apparatus for applying a coating liquid to a base material, the nozzle having a discharge unit for discharging the coating liquid, and before the coating liquid is applied to the base material, and A two-dimensional information acquisition unit that acquires two-dimensional information related to the shape of the coating liquid from the horizontal direction of the discharge unit while being held by the discharge unit, and the two-dimensional information acquired by the two-dimensional information acquisition unit This is achieved by a coating apparatus comprising a calculation unit that calculates a coating amount of the coating liquid based on information.

  Also, there is provided a coating method for applying a coating liquid to a substrate, wherein the coating liquid is discharged from a discharge portion of a nozzle, and is held by the discharge portion before the coating liquid is applied to the substrate. This is achieved by a coating method characterized in that two-dimensional information related to the shape of the coating liquid is obtained from the horizontal direction of the discharge unit and the coating amount of the coating liquid is calculated based on the two-dimensional information. .

  The coating apparatus of the present invention obtains two-dimensional information related to the shape of the coating liquid when viewed from the horizontal direction before being applied to the base material and held in the discharge section. The coating liquid in such a state is held in a state of being deformed in the vertical direction by gravity until it is separated from the discharge unit, but can be regarded as a uniform shape when viewed from any direction in the horizontal direction. . For this reason, by calculating the three-dimensional shape of the coating liquid based on the two-dimensional information, the coating amount can be calculated together with the volume of the coating liquid. In this way, when the coating liquid is viscous like an adhesive such as silver paste, the coating liquid applied to the substrate due to the shape of the coating liquid applied by stringing or the like being not constant. By measuring this, it is possible to avoid a problem that an error occurs. Therefore, the coating apparatus of the present invention can accurately measure the coating amount of the coating liquid, and based on this coating amount, the coating amount can be stably coated by a certain amount.

  In the coating apparatus of the present invention, the two-dimensional information acquisition unit is preferably an image recognition unit that acquires image information of the coating liquid. In the coating method, the two-dimensional information is preferably image information in a state where the coating liquid is viewed from the horizontal direction. By doing this, it is possible to calculate the coating amount of the coating liquid by measuring the image information about the shape of the coating liquid in a horizontal view once, and the measurement and measurement compared to the measurement by the conventional laser displacement measuring device. Since an increase in time required for volume measurement can be prevented, a decrease in productivity can be prevented.

  It is preferable that feedback control is performed so that the coating apparatus has a target coating amount according to the coating amount calculated by the calculation unit. Moreover, it is preferable that the application method performs feedback control so as to achieve a target application amount in accordance with the application amount. In this way, the coating device can be controlled to adjust the target coating amount according to the measured coating amount, the coating amount of the coating liquid can be stabilized, and productivity can be improved. Can be planned.

  According to the present invention, there is provided a coating apparatus and a coating method capable of applying a stable amount of a coating solution such as an adhesive to a substrate to which a semiconductor chip such as a semiconductor element or a solid-state imaging element is bonded, and preventing a decrease in productivity. Can be provided.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Note that, as an example, the coating apparatus of this embodiment will be described using a dispenser that is used to apply an adhesive to a package container as a base material when the solid-state imaging device is bonded to the package container. Moreover, although demonstrated using the adhesive agent used by the die bonding process which adhere | attaches a solid-state image sensor to a package container as a coating liquid, a coating liquid is not specifically limited to an adhesive agent.

  In the present embodiment, a process of applying an adhesive to a substrate using the coating apparatus and the coating method according to the present invention and bonding a solid-state imaging device to the substrate will be described. However, the adhesive application device of the present invention can be applied in a process of applying an adhesive for adhering a semiconductor element to a semiconductor substrate to a semiconductor substrate.

FIG. 1 is a diagram for explaining the configuration of a coating apparatus according to the present invention.
As shown in FIG. 1, the coating apparatus 10 includes a discharge mechanism 13 that discharges the adhesive P to the package container W at a predetermined pressure. The discharge mechanism 13 includes a dispenser nozzle 15 that discharges the adhesive P.

  A controller 11 that pressurizes the adhesive P with air is connected to the discharge mechanism 13 via the supply pipe 12.

  FIG. 2 is a diagram illustrating a state in which the dispenser nozzle is viewed in the horizontal direction (the left-right direction in FIG. 1). The dispenser nozzle 15 is formed with a plurality of cylindrical discharge portions 16 protruding downward in the vertical direction so as to discharge the adhesive P.

  The discharge mechanism 13 is configured to be driven up and down. When the base material W transported by a transport mechanism (not shown) has reached the application position, the discharge mechanism 13 is driven downward to bring the discharge portion 16 of the dispenser nozzle 15 closer to the base material W from the discharge portion 16. The adhesive P is controlled to be discharged onto the substrate W. In addition, after the adhesive P is discharged onto the substrate W, the discharge mechanism 13 is controlled to rise so that the dispenser nozzle 15 is separated from the substrate W.

  When the adhesive P is discharged, a predetermined pressure is applied to the discharge mechanism 13, whereby the adhesive P is ejected from the discharge portion 16 of the dispenser nozzle 15 and expands while being held by the discharge portion 16. At this time, the application mechanism 13 is lowered and the discharge unit 16 approaches the substrate W, and the adhesive P held by the discharge unit 16 adheres to a predetermined part of the substrate W.

  After the adhesive P is applied, the substrate W is transported to a die bonding position where the solid-state imaging element T is attached. At the die bonding position, the solid-state imaging element T held by the attachment member 18 such as an arm controlled so as to be able to be lifted and lowered is attached to the attachment position on the base material W coated with the adhesive P. Here, in the package container W of the present embodiment, a predetermined amount of adhesive P is applied to the attachment region of the solid-state imaging device T called die attach on the bottom surface of the package container W, and this die attach is used as a reference. A solid-state image sensor T is attached.

  The coating apparatus 10 according to this embodiment includes a two-dimensional information acquisition unit 21 that acquires two-dimensional information related to the shape of the adhesive P, and an adhesive P based on the two-dimensional information acquired by the two-dimensional information acquisition unit 21. And a calculation unit 22 for calculating the coating amount.

  The two-dimensional information acquisition means 21 is installed at a height substantially equal to the dispenser nozzle 15 in a state where the dispenser nozzle 15 is in the raised position. In this embodiment, an image recognition unit such as a CCD camera is used as the two-dimensional information acquisition unit 21. Specifically, as shown in FIG. 2, the two-dimensional information acquisition unit 21, when applying the adhesive P, ejects the adhesive P from the discharge portion 16 of the dispenser nozzle 15, and the adhesive P is discharged from the package container W. It is possible to acquire two-dimensional information related to the shape of the adhesive P held in the discharge part 16 as viewed from the horizontal direction before being applied to the liquid and in the state held in the discharge part 16. .

  In addition, in this embodiment, although it is the structure which measures the application quantity of the adhesive agent P discharged from any one among the some discharge parts 16, it is not limited to this in particular, Among the some discharge parts 16 The same number of two-dimensional information acquisition means 21 may be provided so that all or a plurality of them can be measured. Alternatively, the single two-dimensional information acquisition unit 21 may be driven in the horizontal direction to measure all or a plurality of the plurality of ejection units 16. If all of the plurality of discharge units 16 are in communication with the inside of the dispenser nozzle 15, the application mechanism 13 can apply by measuring any one of these discharge units 16 as in this embodiment. It is possible to calculate the total applied amount.

  FIGS. 3A and 3B are views showing the shape of the adhesive as seen from the horizontal direction of the discharge portion. As shown in FIG. 3A, the adhesive P ejected from the discharge unit 16 is further pushed out by applying pressure, and is held at the tip of the discharge unit 16 as shown in FIG. Deforms to hang down due to gravity. Here, in a direction perpendicular to the direction in which gravity acts, that is, in a horizontal direction, the shape is substantially uniform when viewed from any direction. The two-dimensional information acquisition unit 22 acquires, as two-dimensional information, the quadratic curve indicating the contour line of the adhesive P held by the discharge unit 16 or the area of the adhesive P when projected in the horizontal direction. Is. In the image recognition unit of the present embodiment, image information is acquired as two-dimensional information by imaging the adhesive P held by the discharge unit 16.

FIG. 4 is a block diagram showing a control system of the coating apparatus according to the present invention.
As shown in FIGS. 1 and 4, when applying the adhesive P, two-dimensional information related to the shape of the adhesive liquid is acquired from the horizontal direction of the discharge unit, and the two-dimensional information is output to the calculation unit 22 via the signal wiring 23. is doing.

  The calculation unit 22 includes a calculation processing circuit and a program necessary for calculating the application amount of the adhesive P based on the two-dimensional information acquired from the two-dimensional information acquisition unit 22. A computer can be used. In the calculation unit 22, for example, based on a quadratic curve or an area indicating the contour line of the adhesive P, assuming the case of rotating around the central axis, the volume of the adhesive P can be calculated by performing integral calculation. And the coating amount can be measured.

  Moreover, the calculating part 22 can measure the difference with the target application amount according to the calculated application amount. Then, the calculation unit 22 calculates the discharge pressure and the supply amount in the coating device necessary to reach the target coating amount, and outputs the control signal as a control signal to the coating device 10 via the wiring 24, thereby performing feedback control. Is possible.

Next, the procedure for coating with the coating apparatus according to the present invention will be described. FIG. 5 is a flowchart showing a procedure of coating performed by the coating apparatus according to the present invention.
After starting the coating process, the adhesive P, which is a coating liquid, is discharged to the tip of the discharge section 16 of the dispenser nozzle 15 (step 11). At this time, before the adhesive P is applied to the base material (package container W) and in a state of being held by the discharge unit 16, the shape of the coating liquid from the horizontal direction of the discharge unit 16 by the image recognition unit 21. The image information regarding is acquired (step S12).

  The image information acquired by the image recognition unit 21 is output to the calculation unit 22, and the calculation unit 22 calculates the application amount of the adhesive P based on the image information (step S13). Next, in the calculation part 22, it is discriminate | determined whether the calculated application quantity is the range of an appropriate value (step S14). The appropriate value can be set in advance according to the target application amount. When the calculated coating amount is larger or smaller than the appropriate value range, a control signal is output to the coating device 10 to adjust the coating amount by the coating device 10, and the coating amount is feedback controlled (step). S15).

  The coating apparatus 10 resets the coating conditions based on the input control signal (step S16). Here, as an application condition, for example, as shown in FIG. 1, a pressurizing time or an air pressure of the air pressure from the control unit 11 when the adhesive P is pressed from the application mechanism 13.

  When the calculated application amount is in the range of an appropriate value, and after resetting the application condition of the application device 10, the adhesive P discharged from the discharge portion 16 of the dispenser nozzle 15 is applied to the substrate W ( Step S17). It is determined whether or not to continue the coating process (step S18). When the coating process is continued, the next base material W is set at the coating position by the transport mechanism (step S19). Then, the procedure from step S11 to step S17 is repeated until the coating process is completed.

  As described above, the coating apparatus and the coating method according to the present embodiment can obtain the two-dimensional information about the shape of the adhesive P in the state held before the coating on the substrate W and held by the discharge unit 16 from the horizontal direction. To get. The adhesive P in such a state is held in a state of being deformed in the vertical direction by gravity until it is separated from the discharge unit 16, but can be regarded as a uniform shape when viewed from any direction in the horizontal direction. It is. For this reason, the application amount can be calculated together with the volume of the adhesive P by calculating the three-dimensional shape of the coating liquid based on the two-dimensional information. In this way, when the adhesive P is viscous, such as silver paste, the adhesive P applied to the substrate due to the shape of the adhesive P applied by stringing or the like being not constant. By measuring this, it is possible to avoid a problem that an error occurs. Therefore, the coating apparatus 10 can accurately measure the application amount of the adhesive P, and can stably apply the adhesive P by a certain amount based on the application amount.

  In this embodiment, the adhesive is used as an example of the coating liquid. However, the coating apparatus according to the present invention is not limited to the above-described apparatus for applying the adhesive, and the coating liquid is applied with a constant coating amount. It can be applied to a coating apparatus.

  Moreover, if the two-dimensional information acquisition unit 21 is an image recognition unit that acquires image information of the adhesive P as in the coating apparatus 10 of the present embodiment, an image related to the shape of the adhesive P in the horizontal direction view. By measuring the information once, the application amount of the adhesive P can be calculated, and an increase in time required for measurement and volume measurement can be prevented as compared with the case of measuring with a conventional laser displacement measuring device. Therefore, a decrease in productivity can be prevented.

  If the coating apparatus 10 is configured such that feedback control is performed so that the target application amount is obtained according to the application amount calculated by the calculation unit 22, the target application amount is adjusted according to the measured application amount. Therefore, the coating apparatus 10 can be controlled, the application amount of the adhesive P can be stabilized, and productivity can be improved.

It is a figure explaining the structure of the coating device concerning this invention. It is a figure which shows the state which looked at the dispenser nozzle in the horizontal direction. It is a figure which shows the shape of the adhesive agent seen from the horizontal direction of the discharge part. It is a block diagram which shows the control system of the coating device concerning this invention. It is a flowchart which shows the procedure of application | coating performed with the coating device concerning this invention. It is a figure explaining the conventional coating system. It is a figure explaining the state of the adhesive agent apply | coated to the base material. It is a figure explaining the state which measures a coating liquid with a laser displacement meter.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Discharge mechanism 15 Dispenser nozzle 16 Discharge part 21 Two-dimensional information acquisition means 22 Calculation part P Adhesive (coating liquid)
T Solid-state image sensor W Package container (base material)

Claims (6)

A coating apparatus for coating a substrate with a coating liquid,
A nozzle having a discharge section for discharging the coating liquid;
Two-dimensional information acquisition for acquiring two-dimensional information related to the shape of the coating liquid from the horizontal direction of the discharge unit before the coating liquid is applied to the base material and held by the discharge unit Means,
An application apparatus comprising: an arithmetic unit that calculates an application amount of the application liquid based on the two-dimensional information acquired by the two-dimensional information acquisition means.   The coating apparatus according to claim 1, wherein the two-dimensional information acquisition unit is an image recognition unit that acquires image information of the coating liquid.   The coating apparatus according to claim 1, wherein feedback control is performed so that a target coating amount is obtained in accordance with the coating amount calculated by the calculation unit. An application method for applying a coating liquid to a substrate,
The application liquid is discharged from a discharge part of a nozzle, and before the application liquid is applied to the base material and is held by the discharge part, it relates to the shape of the application liquid from the horizontal direction of the discharge part. An application method comprising: obtaining two-dimensional information and calculating an application amount of the application liquid based on the two-dimensional information.   The coating method according to claim 4, wherein the two-dimensional information is image information in a state where the coating liquid is viewed from a horizontal direction.   6. The coating method according to claim 4, wherein feedback control is performed so as to achieve a target coating amount according to the coating amount.

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