JP7149170B2 - Fluid material coating method, coating device, and nozzle head - Google Patents

Description

TECHNICAL FIELD The present invention relates to a coating method, a coating device, and a nozzle head useful for coating a substrate held by a holding part with a fluid material.

In recent years, there has been a demand for thinning and miniaturization of semiconductor products, and attention has been focused on package technologies called panel level packages (PLP) and wafer level packages (WLP). In these packaging technologies, a plurality of semiconductor elements arranged on a panel or wafer are collectively sealed with a resin sealing material.

As the resin encapsulating material, tablet-like, granular, sheet-like, liquid-like encapsulating material is selected according to the encapsulating method. Among them, a liquid resin sealing material is widely used from the viewpoint of easy thinning and miniaturization and easy application to various mounting forms. A liquid resin sealing material is generally applied to a substrate using a dispenser or the like (Patent Document 1, etc.).

JP 2018-118189 A

As the nozzle of the dispenser, a needle-like nozzle or a nozzle having a very small discharge hole is usually used. When these nozzles are used, a fluid material such as a liquid encapsulant is discharged in dots near the center of a sheet-like substrate such as a substrate, or in a line by moving the substrate with respect to the nozzle. is discharged to However, when the fluid material spreads over the substrate, the distribution of the components contained in the fluid material is uneven, resulting in flow marks. In particular, when the thickness of the layer of fluid material to be formed is reduced, flow marks are likely to occur.

One aspect of the present invention is a method of applying a fluid material to a substrate held by a holding part, comprising:
a coating step of applying the fluid material to the base material by discharging the fluid material from a nozzle toward the base material;
In the applying step, when the discharge direction of the fluid material is the z-axis direction, the position of the nozzle portion relative to the substrate is changed by moving the position of at least one of the holding portion and the nozzle portion. A step of changing in the x-axis and y-axis directions,
The nozzle part has a discharge surface facing the base material,
The ejection surface includes an opening area for ejecting the fluid material and a closed area other than the opening area,
The opening area relates to a method of applying a fluid material, in which the opening area is formed along a path drawn two-dimensionally on the ejection surface.

Another aspect of the present invention is a coating device for coating a substrate with a fluid material,
a holding part that holds the base material;
a nozzle section for discharging the fluid material toward the substrate;
Assuming that the discharge direction of the fluid material is the z-axis direction, by moving the position of at least one of the holding portion and the nozzle portion, the relative position of the nozzle portion with respect to the substrate can be changed in the x-axis direction and the y-axis direction. a control unit for axially varying,
The nozzle part has a discharge surface facing the base material,
The ejection surface includes an opening area for ejecting the fluid material and a closed area other than the opening area,
The opening region relates to a fluid material coating device formed along a two-dimensional path drawn on the ejection surface.

Yet another aspect of the present invention is a nozzle head for ejecting a fluid material toward a substrate,
having a discharge surface facing the substrate;
The ejection surface includes an opening area for ejecting the fluid material and a closed area other than the opening area,
The opening region is formed along a path drawn two-dimensionally on the ejection surface,
It relates to the nozzle head, wherein the closed area occupies half or more of the ejection surface.

It is possible to suppress the generation of flow marks when the fluid material is applied onto the substrate.

FIG. 2 is a plan view of the ejection surface of the nozzle head (nozzle portion) according to the first embodiment of the present invention, viewed from the base material side; FIG. 8 is a plan view of the ejection surface of the nozzle head according to the second embodiment of the present invention, viewed from the base material side; FIG. 8 is a plan view of the ejection surface of the nozzle head according to the third embodiment of the present invention, viewed from the base material side; FIG. 11 is a plan view of the ejection surface of a nozzle head according to a fourth embodiment of the present invention, viewed from the substrate side; FIG. 11 is a plan view of the ejection surface of a nozzle head according to a fifth embodiment of the present invention, viewed from the base material side; FIG. 11 is a plan view of the ejection surface of a nozzle head according to a sixth embodiment of the present invention, viewed from the base material side; BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram for demonstrating the coating device which concerns on one Embodiment of this invention. FIG. 4 is a schematic diagram for explaining how a fluid material is supplied to a base material; FIG. 4 is a top view of a substrate provided with flowable material;

A method of applying a fluid material according to one aspect of the present invention is a method of applying a fluid material to a substrate held by a holding unit, and the fluid material is discharged from a nozzle toward the substrate. It has a coating step of coating a base material with a fluid material. In the coating step, when the discharge direction of the fluid material is the z-axis direction, at least one of the holding portion and the nozzle portion is moved to change the position of the nozzle portion relative to the substrate in the x-axis and y-axis directions. A step of changing the direction is provided.

A coating device according to another aspect of the present invention is a coating device for coating a base material with a fluid material, comprising: a holder for holding the base material; and a nozzle for discharging the fluid material toward the base material. By moving at least one of the holding portion and the nozzle portion, the position of the nozzle portion relative to the substrate can be changed in the x-axis direction and the y-axis direction, where the discharge direction of the fluid material is the z-axis direction. and a control unit that changes to

In such a coating method and coating apparatus, the nozzle part has a discharge surface facing the substrate, and the discharge surface has an opening area for discharging the fluid material and a closed area other than the opening area. The opening area is formed along a path drawn two-dimensionally on the ejection surface.
The x-axis direction, the y-axis direction, and the z-axis direction are directions orthogonal to each other.

For example, when sealing semiconductor elements, electronic parts, and the like, a liquid resin sealing material is used as a fluid material. Conventionally, dispensers have been frequently used when applying fluid materials such as liquid sealing materials to sheet-like substrates such as wafers and panels. In a conventional dispenser, the fluid material is discharged in dots from a nozzle onto a partial area (for example, near the center) of the substrate. In addition, by discharging the fluid material from the nozzle while changing the relative position of the nozzle and the substrate, the fluid material may be supplied to the substrate in a line (straight or curved). The encapsulant is then compression molded using, for example, a flat-sided mold. However, when the material is supplied in dots or lines, the distribution of the solid components in the coating film may vary while the fluid material spreads over the entire surface of the substrate. In addition, when the dots or lines spread out, solid components such as fillers contained in the fluid material may be unevenly distributed in the periphery. Such uneven distribution of solid components is observed as flow marks. Flow marks tend to become noticeable particularly when a fluid material is thinly applied.

According to the aspect of the present invention, the ejection port (opening area) is formed along the two-dimensional path (or trajectory) on the ejection surface of the nozzle section. In addition, the fluid material is ejected from the nozzle while changing the relative position of the nozzle with respect to the substrate in the x-axis direction and the y-axis direction with respect to the ejection direction (z-axis direction) of the fluid material. The relative position of the nozzle section with respect to the substrate is changed by moving the position of at least one of the holding section that holds the substrate and the nozzle section. Therefore, the ejected fluid material is supplied onto the substrate so that the two-dimensional shapes overlap. Therefore, even with the same time interval, the flowable material can be supplied to a larger area of the surface of the substrate than conventionally. In addition, by ejecting the fluid material while changing the relative position of the nozzle portion with respect to the substrate by moving the holding portion and/or the nozzle portion, the surface of the substrate can be adjusted according to the shape and/or size of the substrate. It is also possible to supply a small amount of flowable material to a larger area of . As a result, the flowable material can be spread more easily and more uniformly and thinly on the substrate than conventionally. Since uneven distribution of the solid component can be reduced or suppressed, generation of flow marks can be suppressed.

Further, another aspect of the present invention includes the nozzle portion (in other words, nozzle head).

One of the features of the above aspect is the opening region on the ejection surface of the nozzle portion. Another feature is that the fluid material is ejected from the nozzle portion while changing the relative position of the nozzle portion with respect to the substrate. These features will be described in more detail below.

(Nozzle part (or nozzle head))
The fluid material is applied to the substrate held by the holding portion by being discharged from the nozzle portion toward the substrate. The nozzle section has a discharge surface facing the substrate (more specifically, the substrate held by the holding section). The ejection surface includes an open area for ejecting the fluid material and a closed area other than the open area.

The ejection surface is not necessarily a flat surface as long as it can face the area of the base material to which the fluid material is applied, and may be a curved surface. Further, the ejection surface may have unevenness. Note that the ejection surface is the area where the opening area is arranged and the surface facing the substrate when the nozzle portion is viewed from the substrate side. The closed region is preferably flush with the ejection surface. The surface on which this closed region exists may be used as the ejection surface.

In the ejection surface, it is important that the opening area is formed along the two-dimensionally drawn path. As a result, the fluid material ejected from the opening area is supplied onto the substrate so that the two-dimensional shapes overlap. Even with the same time interval, the flowable material can be supplied to a larger area of the surface of the substrate, so that the generation of flow marks can be suppressed as described above.

It should be noted that the expression that the opening region is formed along a path drawn two-dimensionally means that the opening region is formed along one one-dimensional (such as a linear shape) path, or that the opening region is It does not include the case of one dot-shaped ejection hole (zero-dimensional opening area). The opening region may be formed along a two-dimensional path in a plan view of the ejection surface viewed from the substrate side. The opening region may be formed by one ejection slit, or may be an assembly of a plurality of ejection holes and/or ejection slits. When the opening region is formed along a two-dimensional path, when the shape of the opening region is two-dimensional in a plan view (xy plan view) of the ejection surface viewed from the substrate side, A case where a shape (path or trajectory) drawn by virtually connecting a plurality of ejection holes and/or ejection slits is two-dimensional is included.

Preferably, the closed area occupies more than half of the discharge surface (ie, the open area is less than half of the discharge surface). In this case, the thickness of the coating film of the fluid material formed on the substrate tends to become small, and flow marks tend to occur. However, even in such a case, according to the aspect of the present invention, the opening region is formed along the two-dimensional path on the ejection surface, and the relative position of the nozzle portion with respect to the substrate is changed. The generation of flow marks can be effectively suppressed by performing the ejection while allowing the ink to flow.

Note that the expression that the closed region occupies half or more of the ejection surface means that the ratio of the area of the open region is less than 50% when the area of the ejection surface is taken as 100%. The area of the ejection surface refers to the projected area when the entire ejection surface is vertically projected onto the xy plane. The area of the opening region means the projected area when the opening region is projected in the vertical direction onto the xy plane. When the opening area is a set of a plurality of ejection holes and/or ejection slits, the total area of all the ejection holes and ejection slits is the area of the opening area.

The ratio (r _o ) of the area of the opening region to the area of the ejection surface is, for example, less than 50%, may be 30% or less, or may be 10% or less or 5% or less. Normally, the smaller the ratio of the area of the open regions, the smaller the amount of fluid material supplied to the substrate at the same time interval, and the smaller the thickness of the coating film, so flow marks tend to occur. However, even in such a case, according to the aspect of the present invention, the opening region is formed along the two-dimensional path on the ejection surface, and the relative position of the nozzle portion with respect to the substrate is changed. The generation of flow marks can be effectively suppressed by performing the ejection while allowing the ink to flow. The area ratio r ₀ is preferably 0.01% or more, more preferably 0.1% or more. These upper and lower limits can be combined arbitrarily. The area ratio _ro (%) is, for example, 0.01 (or 0.1) ≤ _ro < 50, 0.01 (or 0.1) ≤ _ro ≤ 30, 0.01 (or 0.1) ≦ _ro ≦10, or 0.01 (or 0.1)≦ _ro ≦5.

The area of the ejection surface is not particularly limited, but may be, for example, 50 mm ² or more and 35000 mm ² or less, or 200 mm ² or more and 10000 mm ² or less. The area of the ejection surface is the projected area of the region surrounded by the outer edge of the ejection surface with respect to the substrate. Also, the shape of the ejection surface is not particularly limited, but may be, for example, circular, elliptical, or polygonal (such as square). Alternatively, as shown in FIGS. 1, 5, and 6 to be described later, the shape of the path (or locus) of the opening region may be determined so as to follow the shape of the outer edge of the ejection surface. . For example, when the ejection surface is circular, the path may be circular. When the ejection surface is polygonal (quadrangular, etc.), the route may be polygonal loop (quadrangular loop, etc.). It should be noted that the shape of the ejection surface is the projected shape of the area surrounded by the outer edge of the ejection surface with respect to the substrate.

The opening region may be formed along a path drawn two-dimensionally on the ejection surface, and the shape of the path is not particularly limited. However, it is preferable that the open area is arranged so as to surround part of the closed area. In this case, the fluid material ejected from the opening region is likely to be supplied so as to overlap on the substrate. Even with the same time interval, the flowable material can be supplied to a larger area on the surface of the substrate, which is more effective in suppressing the generation of flow marks.

The shape of the path (or trajectory) is not particularly limited, and may be, for example, a ring shape, a curved shape, a curved shape, or a combination of two or more selected from these shapes. A combination of at least one selected from these shapes and a dot shape (for example, a circular shape, an elliptical shape, a polygonal shape, etc.) and/or a linear shape may be used. Alternatively, the path may be a plurality of spaced straight lines. The shape of the ring is also not particularly limited, and may be a circular ring, an elliptical ring, a polygonal ring (such as a square ring), or an asymmetrical ring (variant ring) on the discharge surface. It may be a combination. Among these, the opening region is preferably formed along at least a ring-shaped, curved and/or bent-shaped path. The ring shape, curved shape, and bent shape on the ejection surface may each be single or multiple (for example, double to quadruple).

For example, when the path is annular, the diameter may be 10 mm or more and 200 mm or less, or may be 20 mm or more and 100 mm or less. Further, for example, in the case of a square ring, one side may be 10 mm or more and 200 mm or less, or may be 20 mm or more and 100 mm or less. The paths are formed by connecting the center lines of the slits in the width direction and/or the centers of the dots. When the shape of the path is circular, the diameter is within the above range, and when the path is quadrangular, the length of one side is within the above range.

The average hole diameter of the discharge holes is, for example, 0.01 mm or more and 2.0 mm or less, and may be 0.05 mm or more and 0.5 mm or less.
The average hole diameter of the ejection holes is obtained by obtaining the diameter of a circle having the same area as that of each ejection hole for a plurality of (for example, 10) arbitrarily selected ejection holes when the ejection surface is viewed from the vertical direction, It is obtained by averaging.

The average slit width of the ejection slits is, for example, 0.01 mm or more and 2.0 mm or less, and may be 0.05 mm or more and 0.5 mm or less. The average slit width is obtained by measuring and averaging the slit widths at a plurality of arbitrarily selected locations (for example, 10 locations) when the ejection surface is viewed in a vertical direction.

The shape of the ejection slit when the ejection surface is viewed from the base material side is not particularly limited, and may be linear, ring, curved, curved, or the like. Ejection slits having two or more shapes selected from these shapes may be arranged on the ejection surface. The shape of the ejection holes when the ejection surface is viewed from the substrate side is preferably dot-shaped. Examples of the dot shape include a circular shape, an elliptical shape, and a polygonal shape, but are not limited to these. Both the ejection slit and the ejection hole may be provided on the ejection surface.

1 to 6 show plan views of the ejection surface of the nozzle portion (nozzle head) viewed from the substrate side. 1 to 6 illustrate the case where the opening region is formed along the ring-shaped path, but the present invention is not limited to these cases. In each of FIGS. 1 to 6, the entire plan view shows the ejection surface.

In the example of FIG. 1 (first embodiment), the ejection surface includes one ejection slit 101a and a closed area 102 other than the ejection slit 101a. The ejection slit 101a has an annular shape and forms an opening area by itself. In the example of FIG. 2 (second embodiment), the ejection surface includes one rectangular ring-shaped ejection slit 101 b and a closed area 102 . The ejection slit 101b is in the shape of a quadrangular ring, and one slit forms an opening region.

The examples of FIGS. 3 to 5 show the case where the opening area is a collection of a plurality of ejection slits.
In the example of FIG. 3 (third embodiment), the ejection surface includes four linear ejection slits 101c and closed areas 102 other than the ejection slits 101c. Four ejection slits 101c form an opening region. On the ejection surface, the four ejection slits 101c are arranged along the rectangular annular path R. As shown in FIG. More specifically, the four ejection slits 101c are arranged on the ejection surface so as to constitute part of each side of the quadrangular annular path R, respectively.

In the example of FIG. 4 (fourth embodiment), the ejection surface includes two curved (specifically, L-shaped) ejection slits 101d and a closed region 102 other than the ejection slits 101d. Two ejection slits 101d form an opening region. On the ejection surface, the two slits 101d are arranged along the quadrangular annular path R. As shown in FIG. More specifically, each of the ejection slits 101d is arranged on the ejection surface so as to constitute a part of two adjacent sides of the rectangular annular path R. As shown in FIG.

In the example of FIG. 5 (fifth embodiment), the ejection surface includes four curved (specifically, arcuate) ejection slits 101e and closed areas 102 other than the ejection slits 101e. Four ejection slits 101e form an opening region. The four slits 101e are arranged along the circular path R on the ejection surface.

FIG. 6 (sixth embodiment) shows an example in which the opening region is a set of a plurality of ejection holes. In FIG. 6, the ejection surface includes a plurality of ejection holes 101f and closed areas 102 other than the ejection holes 101f. Each ejection hole 101f is in the shape of a circular dot. 101 f of several discharge holes are arrange|positioned along the circular path|route R, and form the opening area|region.

In these embodiments, closed regions 102 are present both outside and inside the open region. That is, the open area is formed so as to surround part of the closed area. When an opening region is formed by a plurality of ejection slits or a plurality of ejection holes, closed regions 102 also exist between adjacent ejection slits or between adjacent ejection holes.

In these embodiments, an example in which the shape of the route R is ring-shaped has been shown, but it is not limited to the ring-shaped case as described above. For example, in FIG. 5, one curved ejection slit 101e, or two or three ejection slits 101e are arranged on the ejection surface to form an opening region along a curved path. may By arranging a plurality of discharge holes 101f side by side in a part of the annular path R in FIG. 6 (for example, half or quarter of the annular area), an opening area is formed along the curved path. You may By arranging two or three linear ejection slits 101c as shown in FIG. 3 on the ejection surface, a curved opening region may be formed. It may be arranged. Only one curved ejection slit 101d as shown in FIG. 4 may be arranged on the ejection surface.

In the above embodiment, the case of having ejection slits or ejection holes has been shown, but the present invention is not limited to such cases, and both may be combined. For example, dot-shaped ejection holes may be arranged inside and/or outside the ejection slits shown in FIGS. Alternatively, the opening region may be formed such that the ejection slit and the ejection hole form a path having a ring shape, a curved shape, or a bent shape.

The material of the nozzle portion is not particularly limited, and known materials can be used. The nozzle portion is formed of, for example, an inorganic material such as a metal material, a resin material, or a combination thereof. Structures of the nozzle portion other than those described above are not particularly limited, and known structures can be employed. Also, the members forming the discharge surface may be formed integrally with the nozzle portion, but when they are formed separately, they are fixed by fixing means such as screws.

(Step of changing the relative position of the nozzle part with respect to the substrate (or control part))
In the coating method according to the aspect of the present invention, the relative position of the nozzle portion to the substrate is changed in the coating step of applying the fluid material to the substrate by discharging the fluid material from the nozzle portion. That is, the coating step includes a step of changing the relative position of the nozzle portion with respect to the substrate (position changing step). Moreover, the coating device according to the aspect of the present invention includes a control section that changes the relative position of the nozzle section with respect to the substrate.

The relative position of the nozzle part to the base material is changed in the x-axis direction and the y-axis direction by moving the position of at least one of the holding part and the nozzle part when the discharge direction of the fluid material is the z-axis direction. Let When applying the fluid material to the base material using the nozzle part having the opening area as described above, by changing the relative position of the nozzle part with respect to the base material in this manner, the fluid material is applied to the opening area. are supplied to the surface of the base material so that two-dimensional shapes obtained by reversing the shape of . This allows the flowable material to spread more easily and more uniformly over the surface of the substrate. As a result, uneven distribution of the solid components contained in the fluid material is reduced or suppressed, thereby suppressing the occurrence of flow marks.

The ejection surface (particularly the opening area) of the nozzle portion is normally positioned vertically above the substrate held by the holding portion. Since the holding part is generally arranged to horizontally hold the substrate, it has a horizontal surface for holding the substrate. Therefore, the ejection direction is the direction perpendicular to the horizontal plane of the holding portion, and this direction is the z-axis direction. The holding portion and/or the nozzle are arranged such that the relative position of the nozzle portion with respect to the substrate changes in the x-axis direction and the y-axis direction in a plane parallel to the horizontal plane of the holding portion (i.e., changes two-dimensionally). move the part.

The movement of the holding portion and the movement of the nozzle portion may be performed such that the relative position of the nozzle portion with respect to the substrate changes in the x-axis direction and the y-axis direction while the fluid material is discharged. For example, when moving the holding portion, the holding portion may be moved in the x-axis direction and/or the y-axis direction. Moreover, when moving the nozzle section, the nozzle section may be moved in the x-axis direction and/or the y-axis direction. The movement pattern of the holding portion and the nozzle portion is not particularly limited. For example, one of the holding portion and the nozzle portion may be moved in the x-axis direction and the y-axis direction. Also, both the holding portion and the nozzle portion may be moved in the x-axis direction and the y-axis direction, respectively. One member of the holding portion and the nozzle portion may be moved by a predetermined length in one of the x-axis direction and the y-axis direction, and the other member may be moved in the other direction by a predetermined amount. Also, these movements may be repeated at appropriate intervals. When moving both the holding part and the nozzle part, each member may be moved at the same time, or after one member is moved, the other member may be moved. Alternatively, the movement of one member and the movement of the other member may be repeated alternately. Moreover, if necessary, a plurality of patterns may be selected from these movement patterns and combined.

The relative position of the nozzle part with respect to the substrate is not particularly limited as long as it is changed so as to include movement in both the x-axis and y-axis directions. The relative position of the nozzle part with respect to the substrate may be changed in the x-axis direction and the y-axis direction at the same time. good too. The change in one direction and the change in the other direction may be alternately repeated. Simultaneous changes in the x-axis and y-axis directions and changes in the x-axis and/or y-axis directions may be combined as appropriate. From the viewpoint of enabling more uniform application, it is preferable to change the relative position in a spiral and/or serpentine (especially spiral) manner.

The spiral shape may be a shape similar to a circle (for example, a shape like the arrow A in FIG. 8 described later), or a shape similar to a square (for example, the shape of the spiral part of the thunder pattern (square It may be a spiral shape that spreads out)). A spiral shape or a serpentine shape may be determined according to the shape of the substrate. Note that the movement of the nozzle section and the movement of the holding section are normally performed along the x-axis direction and/or the y-axis direction, respectively. Therefore, the spiral shape does not necessarily have to be a smooth curve. Also, the positions of the start and end of the change are not particularly limited. For example, when the relative position is changed spirally, the relative position may be changed from the inner side (for example, near the center) to the outer side of the base material, or may be changed from the outer side to the inner side. . In addition, if necessary, the surface of the substrate is divided into a plurality of regions, and the position of the nozzle portion relative to the substrate is changed (for example, spirally and/or serpentinely) for each region. good too.

FIG. 7 is a schematic diagram for explaining the coating apparatus according to this embodiment.
The coating device 1 includes a holding section 20 that holds a base material 21, a nozzle section 10 that discharges a fluid material 40 toward the base material 21, and a control section that changes the relative position of the nozzle section 10 with respect to the base material 21. 30. The base material 21 is held on the horizontal surface 20 a of the holding portion 20 . The ejection surface 103 of the nozzle portion 10 is formed with the above-described opening region and closed region. Then, the fluid material 40 is discharged from the opening region of the discharge surface 103 toward the surface (upper surface) of the substrate 21 opposite to the holding portion 20 in the z-axis direction, thereby flowing to the surface of the substrate 21. A protective material 40 is applied. The control unit 30 moves the positions of the holding unit 20 and/or the nozzle unit 10 in the x-axis and/or y-axis directions, thereby changing the relative position of the nozzle unit 10 with respect to the substrate 21 in the x-axis direction and the y-axis direction. change direction. The coating apparatus 1 may include an input/output section 50 for inputting data to and/or outputting data from the control section 30 (or other constituent units of the apparatus 1).

FIG. 8 is a schematic diagram for explaining how the fluid material is supplied to the substrate 21. As shown in FIG. FIG. 9 is a top view of the substrate 21 to which the fluid material has been applied.

FIG. 8 schematically shows a disk-shaped base material 21 such as a semiconductor substrate (wafer or the like) viewed vertically from above. FIG. 8 shows how the fluid material is supplied to the surface of the substrate 21 using a nozzle portion having a discharge surface formed with an annular opening region as shown in FIG. By controlling the movement of the holding part and/or the nozzle part in the x-axis direction and/or the y-axis direction within a plane parallel to the horizontal plane of the holding part, the relative position of the nozzle part with respect to the substrate 21 can be changed in the x-axis direction and/or the y-axis direction. It can be changed in the y-axis direction (more specifically, it can be changed in a spiral shape as indicated by arrow A). The flowable material ejected from the annular opening area becomes a coating film 41 having an annular shape (or similar shape) corresponding to the opening area at the moment it reaches the surface of the substrate 21 . FIG. 8 schematically shows a state in which the annular coating film 41 formed on the surface of the base material 21 at a certain point spirally overlaps in the direction of arrow A as time elapses. there is When the fluid material is continuously supplied to the base material 21 , the coating film 41 is actually formed continuously as the relative position of the nozzle section to the base material 21 changes. In this case, the ring-shaped coating film 41 is more densely formed than shown in FIG.

In the conventional technology, the fluid material is supplied in a dot shape near the center of the base material, or in a line shape (for example, in a spiral shape from a dot-shaped discharge hole along the arrow A in FIG. 8). . Compared to these cases, in the coating method and the coating apparatus according to the above aspects, the fluid material is coated on the surface of the base material so that two-dimensionally shaped coating films overlap. Therefore, as shown in FIG. 9, it is possible to easily form a more uniform coating film 41 of the fluid material 40 on the entire surface of the substrate 21 . The occurrence of flow marks is suppressed by enabling more uniform application.

The position changing step may be performed at least partly while the fluid material is discharged from the nozzle portion toward the substrate in the coating step. However, from the viewpoint of forming a more uniform coating film, it is preferable to perform the position changing step over the entire discharge period. Although the position changing step may be performed intermittently, it is preferable to perform it continuously from the same viewpoint as above.

Elements of the coating method and the coating apparatus relating to the above aspects other than the above features will be described below.
(Coating process)
In the application step, as described above, the fluid material is applied from the nozzle portion toward the substrate. The temperature and atmosphere for application may be determined according to the application and composition of the fluid material.

The thickness of the coating film of the fluid material formed on the surface of the base material in the coating step is the thickness of the coating film obtained by solidifying (e.g., curing) the coating film (or the coating film after molding (e.g., after compression molding)). , 50 μm or more and 500 μm or less. In some cases, the fluid material is applied in such a thickness that the film thickness is as small as 100 μm or less (for example, 50 μm or more and 100 μm or less). Even in such a case, the occurrence of flow marks can be effectively suppressed.

(fluid material)
As the fluid material, any material that can be applied using a dispenser can be used without particular limitation. The flowable material used for coating film formation includes, for example, solids. The solid content may be dissolved in a liquid (solvent, etc.), dispersed in a liquid (dispersion medium, etc.), or melted or softened by heating. In particular, when a fluid material contains a solid component that does not dissolve in a liquid, such as a filler, flow marks are likely to occur in the conventional application method using a dispenser. According to the coating method according to the aspect of the present invention, it is possible to effectively suppress the occurrence of flow marks in the coating film even when a fluid material containing such components is used. Solid components may be either inorganic or organic materials. The solid component dispersed in the fluid material may be particulate, plate-like, fibrous, or the like. In the packaging technology of semiconductor products, the liquid resin encapsulating material used for element encapsulation contains relatively large amounts of solid components such as fillers. A more uniform coating film formation is required. Therefore, according to the coating method according to the aspect of the present invention, it is possible to effectively suppress the generation of flow marks even when such a liquid sealing material is used as the fluid material.

A fluid material such as a liquid sealing material is, for example, a curable resin composition containing a curable resin, a filler, a curing agent and/or a curing accelerator, and the like. The curable resin composition may be either thermosetting or photocurable. Examples of curable resins include epoxy resins. Examples of fillers include ceramic particles such as silica particles. However, the curable resin and filler are not limited to these. The curing agent and curing accelerator are selected according to, for example, the type of curable resin and the application of the fluid material. The curable resin composition may be of a one-component curing type or a two-component curing type.

The content of solid components (especially filler) in the fluid material is not particularly limited. When the solid component content is high, for example, 50% by mass or more (or 60% by mass or more), particularly 70% by mass or more (or 80% by mass or more), flow marks are particularly noticeable in conventional coating methods. easy to become In the coating method according to the aspect described above, it is possible to effectively suppress the generation of flow marks even when the content of solid components such as fillers is so large. The upper limit of the content of solid components in the fluid material is not particularly limited, but is, for example, 95% by mass or less.

The fluid material may further contain additives depending on the application of the fluid material. Examples of such additives include, but are not limited to, silane coupling agents, carbon black, antifoaming agents, leveling agents, pigments, stress relaxation agents, pregelling agents, ion catchers, and the like. do not have.

The viscosity of the fluid material at 25° C. is, for example, 10 Pa·s or more and 800 Pa·s or less, preferably 10 Pa·s or more and 150 Pa·s or less. When the fluid material having such a viscosity is used, even when the ratio of the opening area to the ejection surface is small, it can be ejected smoothly, and a more uniform coating film having a small thickness can be formed.
The above viscosity can be measured at a rotation speed of 10 rpm, for example, using a cone-plate E-type viscometer.

(Base material)
Various materials can be used as the base material depending on the application of the fluid material. According to the above aspect of the present invention, a more uniform coating film can be formed. is preferable, and a substrate may be used. Substrates include substrates with electronic components, aggregates of electronic components, or electronic components themselves.

Substrates include release films, wafers, panels, glass substrates with electronic components, resin substrates, printed wiring boards, and the like. Examples of the release film include polymer films such as polyester (polyethylene terephthalate, polybutylene terephthalate, etc.) and polyamide, but are not limited thereto. If necessary, the surface of the polymer film may be subjected to a release treatment or the like. Wafers include silicon wafers, sapphire wafers, compound semiconductor wafers, and the like. Examples of resin substrates include bismaleimide triazine substrates, polyimide substrates, and fluorine resin substrates. In particular, in package applications such as PLP and WLP, it is required to apply the liquid sealing material more thinly and more uniformly to the surface of the wafer or panel. According to the coating method according to the aspect of the present invention, it is possible to effectively suppress the generation of flow marks even when used for such packaging applications.

(Holding part)
The holding part is not particularly limited in structure and/or material as long as it can hold the base material in a state in which the fluid material discharged from the nozzle part can adhere to the surface of the base material. For example, a known holder used in dispensers may be used. As described above, the holding portion preferably has a horizontal surface on the side that holds the substrate so that the sheet-like or disc-shaped substrate can be stably held.

(Coating device)
The coating device may include at least a holding section, a nozzle section, and a control section, but may also include other components. The applicator device may include known components such as, for example, dispenser devices.

The coating device may include a drive section for moving the holding section and/or the nozzle section, a detection section for detecting the relative position of the nozzle section with respect to the substrate, and the like. The control section may have at least the function of changing (or controlling) the relative position of the nozzle section with respect to the substrate. The control unit receives information from the detection unit, for example, and drives the driving unit based on this information, thereby changing the relative position.

The applicator, if necessary, has a sensor for detecting the amount (or supply speed) of the fluid material supplied to the nozzle, and a sensor for detecting the amount (or ejection speed) of the fluid material ejected from the opening area. , a tank for supplying the fluid material to the nozzle part, a sensor for detecting the remaining amount of the fluid material in the tank, and the like. When a two-liquid curable fluid material is used, the coating device may, if necessary, have a tank containing each liquid and a mixing chamber for mixing each liquid. Based on the information from each sensor, etc., the control unit controls the supply speed and discharge speed by controlling the valves, etc., controls the start and stop of supply and discharge, and controls the fluidity as necessary. The remaining amount of material may be displayed on the input/output unit (HMI). The coating apparatus may also include heating means (heating means) for heating (heating) the nozzle portion, the tank, and/or the supply path.

(others)
The coating film of the fluid material formed on the surface of the substrate by the coating process according to the aspect described above is dried, heat-treated, and/or cured as necessary, depending on the application and composition of the fluid material. It may be used for processing or the like. When a liquid sealing material as a fluid material is applied to the surface of a substrate as a base material, the surfaces of the substrate and the substrate are sealed by curing the coating film formed on the surface of the substrate in the coating process. It is possible to obtain a sealing body containing a cured product of the liquid sealing material.

The coating method and coating apparatus according to the above aspects of the present invention are useful for coating various substrates with a fluid material to form a more uniform coating film. In particular, it is useful when applying a liquid resin sealing material for sealing a substrate (especially a package such as PLP or WLP) to the substrate.

1: Coating device, 10: Nozzle part (nozzle head), 20: Holding part, 20a: Horizontal surface, 21: Base material (substrate), 30: Control part, 40: Fluid material (liquid resin sealing material), 41: coating film, 50: input/output unit, 101a to 101e: ejection slit, 101f: ejection hole, 102: closed area, 103: ejection surface, R: path (trajectory)

Claims (9)

A method of applying a fluid material to a substrate held by a holding part, comprising:
a coating step of applying the fluid material to the base material by discharging the fluid material from a nozzle toward the base material;
In the applying step, when the discharge direction of the fluid material is the z-axis direction, the position of the nozzle portion relative to the substrate is changed by moving the position of at least one of the holding portion and the nozzle portion. A step of changing in the x-axis direction and the y-axis direction,
The nozzle part has a discharge surface facing the base material,
The ejection surface includes an opening area for ejecting the fluid material and a closed area other than the opening area,
The opening region is formed along a path drawn two-dimensionally on the ejection surface ,
The method of applying a fluid material , wherein the open area is arranged to partially surround the closed area . 2. The method of applying a fluid material according to claim 1, wherein said opening region is a collection of a plurality of ejection holes and/or ejection slits. 3. The method of applying a fluid material according to claim 1, wherein the closed area occupies half or more of the ejection surface. The method of applying a fluid material according to any one of claims 1 to 3 , wherein the ratio of the area of the opening region to the area of the ejection surface is 5% or less. The method of applying a fluid material according to any one of claims 1 to 4 , wherein the opening region is formed along the path in a ring shape, curved shape, or curved shape. The method of applying a fluid material according to any one of claims 1 to 5 , wherein in the applying step, the relative position of the nozzle part with respect to the base material is spirally changed. A coating device for coating a base material with a fluid material,
a holding part that holds the base material;
a nozzle section for discharging the fluid material toward the substrate;
Assuming that the discharge direction of the fluid material is the z-axis direction, by moving the position of at least one of the holding portion and the nozzle portion, the relative position of the nozzle portion with respect to the substrate can be changed in the x-axis direction and the y-axis direction. a control unit for axially varying,
The nozzle part has a discharge surface facing the base material,
The ejection surface includes an opening area for ejecting the fluid material and a closed area other than the opening area,
The opening region is formed along a path drawn two-dimensionally on the ejection surface ,
The fluid material applicator , wherein the open area is arranged to partially surround the closed area . A nozzle head for ejecting a fluid material,
having a discharge surface,
The ejection surface includes an opening area for ejecting the fluid material and a closed area other than the opening area,
The opening region is formed along a path drawn two-dimensionally on the ejection surface ,
The open area is arranged to surround a part of the closed area ,
The nozzle head, wherein the closed area occupies half or more of the ejection surface. 9. The nozzle head according to claim 8 , wherein said closed area of said ejection surface is flush.

Images