WO2014010237A1

WO2014010237A1 - Method for producing semiconductor device

Info

Publication number: WO2014010237A1
Application number: PCT/JP2013/004255
Authority: WO
Inventors: 拓也作田; 寛和伊藤; 圭正杉本; 拓也三木; 酒井　峰一
Original assignee: 株式会社デンソー
Priority date: 2012-07-12
Filing date: 2013-07-10
Publication date: 2014-01-16
Also published as: JP2014033177A

Abstract

This method for producing semiconductor device has the steps of: preparing a semiconductor wafer (40); positioning an adhesive (20) at a predetermined locations on the semiconductor wafer (40); dividing the semiconductor wafer (40) into individual semiconductor chips (30) through cutting by dicing; preparing a substrate (10), mounting the semiconductor chips (30) onto the substrate (10) through the adhesive (20); and precuring the adhesive (20). Precuring of the adhesive is carried out prior to positioning of the adhesive, or subsequent to positioning of the adhesive. Precuring of the adhesive is carried out prior to the cutting by dicing.

Description

Manufacturing method of semiconductor device

Cross-reference of related applications

The present disclosure is based on Japanese Application No. 2012-156114 filed on July 12, 2012 and Japanese Application No. 2013-20067 filed on February 5, 2013. Is used.

The present disclosure relates to a method for manufacturing a semiconductor device in which a semiconductor wafer is diced and cut into semiconductor chips and then the semiconductor chips are mounted on a substrate.

Conventionally, a dicing method of a semiconductor wafer has been proposed in Patent Document 1, for example. Specifically, Patent Document 1 describes a method of dicing a semiconductor wafer by applying an adhesive to one surface of a semiconductor wafer and inserting a dicing blade from the adhesive side.

However, in the above conventional technique, when a soft adhesive is used, there is a problem that when the semiconductor wafer is diced and cut, the soft adhesive is caught as a foreign matter in the dicing blade.

Japanese Patent Laid-Open No. 2002-25945

An object of the present disclosure is to provide a method of manufacturing a semiconductor device that can be cut by dicing so as not to entrap foreign matter even if a soft adhesive is provided on a conductor wafer.

In the first aspect of the present disclosure, a method for manufacturing a semiconductor device includes preparing a semiconductor wafer, placing an adhesive at a predetermined position on one surface of the semiconductor wafer, and dicing the semiconductor wafer. The semiconductor wafer is divided into individual semiconductor chips, a substrate is prepared, the semiconductor chip is mounted on the substrate via the adhesive, and the adhesive is temporarily cured. The temporary curing of the adhesive is performed before the placement of the adhesive or after the placement of the adhesive. The temporary curing of the adhesive is performed before the dicing cut.

According to the manufacturing method of the semiconductor device, since the semiconductor wafer is diced and cut after the adhesive is hardened to some extent by the temporary curing step, it is possible to prevent the soft adhesive from being caught in the dicing blade as a foreign matter. it can. Therefore, even if a soft adhesive is provided on the semiconductor wafer, dicing can be cut so that no foreign matter is caught in the dicing blade.

As an alternative, a portion of the adhesive that does not contact the semiconductor wafer may be covered with a cover film. In this case, when the adhesive is disposed on one surface of the semiconductor wafer, the adhesive is covered with the cover film. For this reason, it can prevent that the coupling agent which determines adhesiveness is washed from an adhesive agent at the time of a dicing cut. That is, it is possible to prevent a decrease in the adhesive coupling agent.

As an alternative, the method for manufacturing a semiconductor device may include a method in which the adhesive is not disposed on one surface of the semiconductor wafer after the placement of the adhesive and the temporary curing of the adhesive and before the dicing cut. It may further include disposing a protective material harder than the adhesive. In the dicing cut, the semiconductor wafer is diced and cut in a state where the protective material is disposed on one surface of the semiconductor wafer. In this case, since the region where the adhesive is not disposed on one surface of the semiconductor wafer is covered with the protective material, the shavings adhere to the region, or the shavings attached to the region are prevented from adhering to the adhesive. be able to. Further, since the protective material is harder than the adhesive, it is difficult for foreign matter to come out when the protective material is shaved. For this reason, the adhesion of foreign matter to the adhesive can be prevented.

The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description with reference to the accompanying drawings. The drawing
FIG. 1 is a cross-sectional view of the semiconductor device according to the first embodiment. FIG. 2A to FIG. 2D are diagrams showing manufacturing steps of the semiconductor device shown in FIG. FIG. 3 is a diagram illustrating a manufacturing process of the semiconductor device according to the second embodiment. FIG. 4 is a diagram showing how the semiconductor wafer is diced and cut from the cover film side in the second embodiment. FIG. 5 is a diagram showing a state where the cover film is peeled off from the semiconductor chip in the second embodiment. FIG. 6 is a diagram illustrating a state in which an adhesive is disposed on the cover film in the third embodiment. FIG. 7 is a plan view of a cover film according to the third embodiment. FIG. 8 is a diagram illustrating a manufacturing process of the semiconductor device according to the third embodiment. FIG. 9A and FIG. 9B are perspective views showing an example of the uneven structure on the surface of the cover film according to the fifth embodiment. FIG. 10 is a diagram illustrating a dicing process according to the sixth embodiment. FIG. 11 is a diagram showing a state where the semiconductor chip is removed from the cover film in the sixth embodiment. FIG. 12 is a diagram showing a protective material process according to the seventh embodiment, FIG. 13 is a diagram illustrating a dicing process according to the seventh embodiment. FIG. 14A to FIG. 14F are diagrams showing examples of the planar pattern of the adhesive in the eighth embodiment. FIG. 15A and FIG. 15B are diagrams showing manufacturing steps according to the ninth embodiment. FIG. 16 is a diagram illustrating a manufacturing process according to the ninth embodiment. FIG. 17 is a plan view of a semiconductor chip according to the tenth embodiment, FIG. 18 is a diagram showing an adhesive process according to the eleventh embodiment, FIG. 19 is a diagram showing a mounting process according to the eleventh embodiment. FIG. 20 is a cross-sectional view of the semiconductor device completed by the mounting process shown in FIG. 21A is a plan view and a cross-sectional view of a semiconductor device without an adhesive leak path, and FIG. 21B is a plan view and a cross-sectional view of a semiconductor device with an adhesive leak path. FIG. 22 is a diagram showing a mounting process according to the twelfth embodiment. FIG. 23 is a diagram illustrating a mounting process according to the thirteenth embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the semiconductor device according to this embodiment includes a substrate 10, an adhesive 20, and a semiconductor chip 30.

The substrate 10 is formed with an electric circuit and serves as a base of the semiconductor device. For example, a printed circuit board or a package is used as the substrate 10.

The adhesive 20 is for fixing the semiconductor chip 30 to the substrate 10. A silicone-based adhesive is used as the adhesive 20. Silicone adhesives are softer than epoxy adhesives.

The semiconductor chip 30 is a semiconductor chip having a predetermined structure formed on a semiconductor substrate. For example, an inertial sensor structure such as an acceleration sensor or a yaw rate sensor is formed on the surface 31 side of the semiconductor chip 30. The back surface 32 side of the semiconductor chip 30 is fixed to the substrate 10 via the adhesive 20.

The structure of the semiconductor chip 30 and the electric circuit of the substrate 10 are electrically connected by, for example, a bonding wire (not shown). The above is the configuration of the semiconductor device according to the present embodiment.

Next, a method for manufacturing the semiconductor device shown in FIG. 1 will be described with reference to FIGS. 2 (a) to 2 (d). First, a preparation process for preparing the semiconductor wafer 40 is performed. On the other surface 42 side opposite to the one surface 41 of the prepared semiconductor wafer 40, a fine structure such as an acceleration sensor is formed in units of semiconductor chips 30 by, for example, MEMS technology.

Subsequently, in the process shown in FIG. 2A, an adhesive process is performed. Specifically, the mask 50 is disposed on the one surface 41 of the semiconductor wafer 40. For example, a metal mask or a mesh mask is used as the mask 50. The pattern of the mask 50 is a pattern in which a portion corresponding to each semiconductor chip 30 in the one surface 41 of the semiconductor wafer 40 is opened.

Then, the adhesive 20 is screen-printed on the one surface 41 of the semiconductor wafer 40 using the mask 50. As a result, the adhesive 20 is disposed at a predetermined position on the one surface 41 of the semiconductor wafer 40. Thus, since the adhesive 20 is arrange | positioned for every semiconductor chip 30, each adhesive 20 corresponding to each semiconductor chip 30 is isolate | separated, without contacting, respectively.

Thus, since an appropriate amount of the adhesive 20 is disposed at a predetermined position on the one surface 41 of the semiconductor wafer 40, the adhesive 20 is not wasted. That is, since the adhesive 20 is disposed on the semiconductor wafer 40 as much as necessary, for example, a part of the size corresponding to the semiconductor chip 30 is not cut out from the roll-shaped adhesive sheet and the remaining adhesive sheet is not discarded. Therefore, there is a great effect in reducing the cost of the adhesive 20.

Note that the adhesive 20 may be directly screen-printed on the one surface 41 of the semiconductor wafer 40 without using the mask 50.

Subsequently, in the process shown in FIG. 2B, a temporary curing process is performed. In the present embodiment, the adhesive 20 after the adhesive 20 is disposed on the one surface 41 of the semiconductor wafer 40 is temporarily cured. Specifically, the adhesive 20 is temporarily cured by a method of heating the adhesive 20 or a method of irradiating the adhesive 20 with laser or ultraviolet rays. Thereby, the elastic modulus of the adhesive 20 that has been softened is improved.

Thereafter, in the process shown in FIG. 2C, a dicing process is performed. That is, the semiconductor wafer 40 is fixed to a dicing tape (not shown), and the semiconductor wafer 40 is diced along the dotted line in FIG. Thus, the semiconductor wafer 40 is divided into individual semiconductor chips 30.

Here, as described above, since the adhesive 20 is disposed at a predetermined position rather than the entire surface 41 of the semiconductor wafer 40, the gap between the cutting line of the dicing blade 51 in the semiconductor wafer 40 and the adhesive 20 is between. There is a gap. Due to the presence of this gap, it is possible to prevent foreign matter that is shavings from adhering to the adhesive 20. Further, since the dicing blade 51 does not directly contact the adhesive 20, the adhesive 20 is not scraped or turned up by the dicing blade 51.

And since the semiconductor wafer 40 is diced and cut in a state where the adhesive 20 is temporarily cured in the temporary curing step, it is possible to prevent the soft adhesive 20 from being caught in the dicing blade 51 as a foreign matter. Therefore, the dicing blade 51 can be diced and cut so that no foreign matter is caught in the dicing blade 51.

After the dicing process, a mounting process is performed in the process shown in FIG. In the mounting process, the substrate 10 is prepared, and the semiconductor chip 30 is mounted on the substrate 10 via the adhesive 20. Specifically, the semiconductor chip 30 is removed from the dicing tape and placed on the substrate 10. Then, the adhesive 20 is fully cured by applying heat.

Thereafter, a wire bonding step is performed to electrically connect the sensor structure of the semiconductor chip 30 and the electric circuit of the substrate 10. Thus, the semiconductor device shown in FIG. 1 is completed.

(Second Embodiment)
In the present embodiment, parts different from the first embodiment will be described. The present embodiment is characterized in that the adhesive 20 is covered with a cover film.

Specifically, the adhesive 20 is disposed on one surface 41 of the semiconductor wafer 40, and after the temporary curing step shown in FIG. 2B, the semiconductor wafer 40 of the adhesive 20 is bonded to the semiconductor wafer 40 as shown in FIG. A cover film process of covering the non-contact portion with the cover film 52 is performed. In other words, the cover film 52 covers the pre-cured adhesive 20 and the cover film 52 covers a region of the one surface 41 of the semiconductor wafer 40 where the pre-cured adhesive 20 is not disposed. The semiconductor wafer 40 is fixed with a dicing tape 53.

Thereafter, the dicing process shown in FIG. In the present embodiment, as shown in FIG. 4, the cover film 52 and the semiconductor wafer 40 are diced with a dicing blade 51 from the cover film 52 side. Here, since the adhesive 20 is covered with the cover film 52, it is possible to prevent the coupling agent that determines the adhesiveness of the adhesive 20 from being washed from the adhesive 20 when the semiconductor wafer 40 is diced. . That is, a decrease in the coupling agent of the adhesive 20 can be prevented.

Further, since the adhesive 20 is covered with the cover film 52, it is possible to prevent the shavings of the semiconductor wafer 40 from adhering to the adhesive 20.

Furthermore, since the area | region where the adhesive 20 is not arrange | positioned is covered with the cover film 52 among the one surface 41 of the semiconductor wafer 40, it can prevent that the shavings adhering to the said area | region adheres to the adhesive 20. FIG.

Thus, when the semiconductor wafer 40 is divided into the semiconductor chips 30, a part of the cover film 52 is on each semiconductor chip 30. Therefore, before the mounting step shown in FIG. 2D, as shown in FIG. 5, a tape 54 is applied to the entire cover film 52 after the dicing step, and the tape 54 is lifted to cover each semiconductor chip 30. The piece of film 52 is peeled off.

Thereafter, the mounting process shown in FIG. As described above, the adhesive 20 can be covered with the cover film 52.

(Third embodiment)
In the present embodiment, parts different from the above embodiments will be described. In the present embodiment, before the adhesive 20 is disposed on the one surface 41 of the semiconductor wafer 40, the cover film process is performed before the temporary curing process, the temporary curing process is performed after the cover film process, and the temporary curing process is performed. It is characterized by performing an adhesive process.

Specifically, after the preparation step, as shown in FIG. 6, a cover film 52 is prepared, and the adhesive 20 is screen-printed on the surface 55 of the cover film 52 on the one surface 41 side of the semiconductor wafer 40.

Since the adhesive 20 is soft, in order to prevent the adhesive 20 from spreading, an adhesive having a recess 56 in which the surface 55 of the cover film 52 is recessed is used as shown in FIG. Therefore, the adhesive 20 is screen-printed on each recess 56 of the cover film 52. The surface 55 of the cover film 52 may include not only the surface that contacts the one surface 41 of the semiconductor wafer 40 but also the wall surface and bottom surface of the recessed portion 56.

The temporary curing process is performed after this cover film process. Then, as shown in FIG. 8, the temporarily cured adhesive 20 is attached to one surface 41 of the semiconductor wafer 40 together with the cover film 52. As a result, the adhesive 20 is disposed on the one surface 41 of the semiconductor wafer 40, and the region of the one surface 41 of the semiconductor wafer 40 where the adhesive 20 is not disposed is covered with the cover film 52.

The subsequent steps after the dicing step are the same as those in the second embodiment. As described above, the adhesive 20 may be disposed on the one surface 41 of the semiconductor wafer 40 after being applied to the cover film 52 and temporarily cured.

(Fourth embodiment)
In the present embodiment, parts different from the third embodiment will be described. In this embodiment, the cover film process is performed before the adhesive 20 is disposed on the one surface 41 of the semiconductor wafer 40 and before the temporary curing process. That is, after the preparation step, the adhesive 20 is screen-printed on the cover film 52 as shown in FIG.

Then, an adhesive process is performed after this cover film process. As a result, the adhesive 20 is disposed on the one surface 41 of the semiconductor wafer 40, and the region of the one surface 41 of the semiconductor wafer 40 where the adhesive 20 is not disposed is covered with the cover film 52.

At this stage, the adhesive 20 is still soft. Therefore, the adhesive 20 is temporarily cured by performing the temporary curing step. The subsequent steps after the dicing step are the same as those in the second embodiment.

(Fifth embodiment)
In the present embodiment, parts different from the second to fourth embodiments will be described. The present embodiment is characterized in that a cover film 52 having a concavo-convex structure on the surface 55 is used.

As the concavo-convex structure, for example, there are a slit 57 shown in FIG. 9A and a protrusion 58 shown in FIG. 9B. These slits 57 and protrusions 58 are also provided on the bottom surface of the recessed portion 56. Note that the slit 57 and the protrusion 58 may be provided on the side surface of the recessed portion 56.

The cover film 52 can be easily peeled off from the semiconductor wafer 40 by the uneven structure such as the slits 57 and the protrusions 58.

For the correspondence between the description of the present embodiment and the description of the scope of claims, the slit 57 and the protrusion 58 correspond to the “concavo-convex structure” of the scope of claims.

(Sixth embodiment)
In the present embodiment, parts different from the second to fourth embodiments will be described. In the present embodiment, as shown in FIG. 10, in the dicing process, the semiconductor wafer 40 is diced with a dicing blade 51 from the other surface 42 side opposite to the one surface 41 of the semiconductor wafer 40. At this time, the cover film 52 is half cut without being completely cut.

In the mounting process, as shown in FIG. 11, the semiconductor chips 30 are removed one by one from the cover film 52 that is joined together and mounted on the substrate 10. Thus, since it is not necessary to remove the cover film 52 from each semiconductor chip 30 that has been diced, the process can be simplified.

(Seventh embodiment)
In the present embodiment, parts different from the above embodiments will be described. In the present embodiment, the protective material process shown in FIG. 12 is performed after the adhesive process shown in FIG. 2A and the temporary curing process shown in FIG. 2B and before the dicing process.

Specifically, a protective material 60 that is harder than the adhesive 20 is disposed in a region of the one surface 41 of the semiconductor wafer 40 where the adhesive 20 is not disposed. For example, a material made of polyimide is used as the protective material 60.

When the protective material 60 is disposed on the semiconductor wafer 40, the height of the protective material 60 with respect to the one surface 41 of the semiconductor wafer 40 is set lower than that of the adhesive 20. This prevents the protective material 60 from covering the adhesive 20.

Thereafter, in the dicing process, as shown in FIG. 13, the semiconductor wafer 40 is diced and cut in a state where the protective material 60 is disposed on the one surface 41 of the semiconductor wafer 40. Thereby, since the area | region where the adhesive 20 is not arrange | positioned is covered with the protective material 60 among the one surfaces 41 of the semiconductor wafer 40, the shavings adhere to the said area | region, or the shavings adhering to the said area | region are the adhesive 20 Can be prevented from adhering to the surface. Further, since the protective material 60 is harder than the adhesive 20, it is difficult for foreign matter to be produced when the protective material 60 is shaved. For this reason, adhesion of a foreign substance to the adhesive 20 can be suppressed.

In the mounting process, the semiconductor chip 30 is mounted on the substrate 10. At this time, it may be mounted with the protective material 60 left on the semiconductor chip 30 removed, or may be mounted with the protective material 60 left on the semiconductor chip 30.

When the semiconductor chip 30 is mounted on the substrate 10 with the protective material 60 remaining on the semiconductor chip 30 even after the dicing cut, the soft adhesive 20 can be continuously supported by the protective material 60. For this reason, deformation of the adhesive 20 can be suppressed when the semiconductor chip 30 is mounted.

(Eighth embodiment)
In the present embodiment, parts different from the above embodiments will be described. The present embodiment is characterized in that the adhesive 20 is arranged in a predetermined pattern in the adhesive process in the adhesive process.

Here, the planar pattern of the adhesive 20 is a planar pattern of the adhesive 20 in one semiconductor chip 30. In other words, it is not a planar pattern on the entire surface 41 of one semiconductor wafer 40.

Specifically, the planar pattern of the adhesive 20 includes a cross shape in FIG. 14 (a), a bow tie shape in FIG. 14 (b), a round shape in FIG. 14 (c), that is, a circular shape, and FIG. An elliptical shape, a rectangular frame shape in FIG. 14E, or a triangular shape in FIG.

Note that the bow tie shape is a shape in which the apexes of two triangles overlap each other. The triangular shape is an example of a polygonal shape, and may be a quadrangular shape or a pentagonal shape.

In the semiconductor chip 30, stress is applied to the region where the adhesive 20 is applied. That is, in each planar pattern shown in FIG. 14A to FIG. 14F, the stress of the adhesive 20 is not applied to the blank portion where the adhesive 20 is not located. Therefore, when a structure that is not desired to be stressed is formed on the semiconductor chip 30, if a planar pattern of the adhesive 20 is selected so that the structure and the adhesive 20 do not overlap in the mounting direction of the semiconductor chip 30. good.

In this way, the planar pattern of the adhesive 20 is made to correspond to the structure formed on the semiconductor chip 30 when the semiconductor chip 30 is formed with a fine structure such as a comb-teeth structure of a capacitive acceleration sensor. Especially effective. That is, it is because the thermal distortion and mounting stress to the area | region where the adhesive agent 20 is not apply | coated among the semiconductor chips 30 can be suppressed. Of course, the structure formed in the semiconductor chip 30 is not limited to the acceleration sensor, but may be another structure such as an angular velocity sensor.

Further, since the mounting stress of the semiconductor chip 30 can be suppressed, there is an advantage that the temperature characteristic adjustment inspection after the semiconductor chip 30 is assembled to the substrate 10 becomes unnecessary, and the manufacturing process can be simplified.

(Ninth embodiment)
In the present embodiment, parts different from the above embodiments will be described. The present embodiment is characterized in that the structure of the semiconductor chip 30 and the electric circuit of the substrate 10 are electrically connected without connecting the structure of the semiconductor chip 30 and the electric circuit of the substrate 10 with bonding wires. Yes.

Specifically, in the manufacturing method described in the first embodiment, in the adhesive process shown in FIG. 2A, the one surface 41 of the semiconductor wafer 40 is exposed as the adhesive 20 as shown in FIG. 15A. The one having the opening 21 to be disposed is disposed on one surface 41 of the semiconductor wafer 40. That is, the opening 21 is provided so that a pad (not shown) formed on the one surface 41 of the semiconductor wafer 40 is not covered with the adhesive 20.

Further, as shown in FIG. 15B, a conductive adhesive 22 is disposed in the opening 21. Specifically, the conductive adhesive 22 is disposed on a pad (not shown) formed on the one surface 41 side of the semiconductor wafer 40 by a screen printing method or a dispensing method. This pad (not shown) is electrically connected to the structure on the other surface 42 side of the semiconductor wafer 40 by a through electrode or the like.

Subsequently, a dicing process is performed, and in the subsequent mounting process, a substrate 10 having a pad formed at a position corresponding to the conductive adhesive 22 is prepared. Then, as shown in FIG. 16, the semiconductor chip 30 is mounted on the substrate 10, thereby electrically connecting the semiconductor chip 30 and the substrate 10 via the conductive adhesive 22.

As described above, by providing the opening 20 in the adhesive 20 in advance and disposing the conductive adhesive 22 in the opening 21, the semiconductor chip 30 can be connected to the semiconductor chip 30 via the conductive adhesive 22 without performing wire bonding. The substrate 10 can be electrically connected. For this reason, a wire bonding process can be omitted.

The opening 21 provided in the adhesive 20 is not a through-hole, and the side surface of the adhesive 20 may be recessed inside, or one of the four corners of the adhesive 20 may be removed. Of course, also in this embodiment, the cover film 52 shown in the second to sixth embodiments may be used, or the protective material 60 shown in the seventh embodiment may be used.

(10th Embodiment)
In the present embodiment, parts different from the ninth embodiment will be described. As shown in FIG. 17, the adhesive 20 is not provided in the adhesive 20, but is applied to the end of the semiconductor chip 30 by, for example, a dispensing process. Further, a pad 33 is provided on the opposite side of the semiconductor chip 30 on the side where the adhesive 20 is disposed on the back surface 32 where the adhesive 20 is disposed.

Thus, when the adhesive 20 is provided on a part of the back surface 32 of the semiconductor chip 30, the semiconductor chip 30 can be mounted on the substrate 10 in a cantilever manner. Thereby, since the area of the adhesive 20 to be used becomes smaller than each said embodiment, it becomes possible to further reduce stress.

(Eleventh embodiment)
In the present embodiment, parts different from the first embodiment will be described. The present embodiment is characterized in that the timing of temporary curing of a part of the adhesive 20 is shifted. For this reason, in the adhesive process shown in FIG. 2A after the preparation process, as shown in FIG. 18, a part of the adhesive 20 sealed in the capsule 23 is used as a semiconductor wafer as shown in FIG. It is arranged at a predetermined position on one surface 41 of 40. In FIG. 18, one semiconductor chip 30 of the semiconductor wafer 40 is illustrated.

The capsule 23 is a hollow spherical container and is a so-called shell. As the material of the capsule 23, a material that does not contain a component that hardens the adhesive 20 is employed. For example, acrylic resin is employed. The size of the capsule 23 is, for example, on the order of 100 μm. It is preferable that the capsule 23 has a waterproof property in consideration of the case where water is used in a later step of the adhesive process. A large number of capsules 23 are mixed in the adhesive 20 in advance. The number of capsules 23 mixed in the adhesive 20 is determined according to the viscosity of the adhesive 20, the temporarily cured shape of the adhesive 20 when the adhesive 20 is temporarily cured, and the like.

Thus, since a part of the adhesive 20 is encapsulated in the capsule 23, the adhesive 20 in the capsule 23 and the adhesive 20 outside the capsule 23 are completely separated. In other words, the adhesive 20 in the capsule 23 is not affected by the outside of the capsule 23 unless the capsule 23 is broken.

Then, when the adhesive 20 is disposed on the one surface 41 of the semiconductor wafer 40, the outer edge of the adhesive 20 has a cornered shape as shown in FIG. That is, the groove 24 is formed in the central portion of the adhesive 20. This is because the adhesive 20 adhered to the opening of the mask 50 is lifted when the mask 50 is lifted from the semiconductor wafer 40 after the adhesive 20 is screen-printed on the one surface 41 of the semiconductor wafer 40 using the mask 50. This is because.

Note that it is conceivable to reduce the viscosity of the adhesive 20 so that the corners of the outer edge of the adhesive 20 do not stand. However, the outer edge portion of the adhesive 20 hangs down without maintaining its shape. As a result, since the adhesive 20 has a conical shape with a protruding central portion, the bonding area between the adhesive 20 and the substrate 10 cannot be secured. Therefore, it is not preferable to lower the viscosity of the adhesive 20.

Subsequently, a part of the adhesive 20 is temporarily cured in the temporary curing step shown in FIG. Thereby, the adhesive 20 located outside the capsule 23 is temporarily cured without temporarily curing the adhesive 20 in the capsule 23. That is, the temporary curing timing of the adhesive 20 in the capsule 23 is changed with time. Specifically, by encapsulating a part of the adhesive 20 in the capsule 23, the timing for temporarily curing the adhesive 20 in the capsule 23 is set to be higher than the timing for temporarily curing the adhesive 20 outside the capsule 23. Delay.

Then, in the mounting process shown in FIG. 2 (d) after the dicing process shown in FIG. 2 (c), the adhesive 20 is fully cured by applying heat as shown in FIG. At this time, the acrylic resin constituting the capsule 23 is decomposed at 80 ° C., for example. That is, the capsule 23 is broken by heat applied to the adhesive 20 in order to fully cure the adhesive 20. That is, the curing timing of the adhesive 20 in the capsule 23 is not the timing of the temporary curing process but the timing of this mounting process. In this way, the semiconductor chip 30 is attached to the substrate 10 via the adhesive 20 that has not been temporarily cured in the temporary curing step, that is, the adhesive 20 enclosed in the capsule 23 and the adhesive 20 that has been temporarily cured in the temporary curing step. Implement.

Then, by destroying the capsule 23 as described above, as shown in FIG. 20, the fluid adhesive 20 enclosed in the capsule 23 that has not been temporarily cured flows out of the capsule 23 and is temporarily cured. The gap between the groove 24 of the agent 20 and the substrate 10 is filled. For this reason, it is possible to eliminate a leak path in which the groove 24 of the temporarily cured adhesive 20 is connected to the outside. In addition, the adhesion area and the sealing property of the adhesive 20 to the substrate 10 can be ensured.

In FIGS. 18 to 20 described above, the thickness of the adhesive 20 is drawn to be thicker than the thickness of the substrate 10 or the semiconductor chip 30, so that the shape of the adhesive 20 can be understood schematically. It is. Therefore, actually, the adhesive 20 is sufficiently thinner than the substrate 10 and the semiconductor chip 30 as shown in FIG.

Such an effect of eliminating the leak path is particularly effective when a pressure sensor is employed as the semiconductor chip 30. For example, when the pressure sensor is configured to detect relative pressure, the substrate 10 has a through hole 11 for introducing a pressure medium, as shown in FIGS. 21 (a) and 21 (b). is doing. Further, the semiconductor chip 30 has a diaphragm 35 that is thinned by forming a recess 34 on the back surface 32. A configuration in which the diaphragm 35 is deflected due to a pressure difference between a pressure received from the front surface 31 side of the semiconductor chip 30 and a pressure received from the back surface 32 side through the through hole 11 of the substrate 10, and a relative pressure is detected according to the amount of the deflection. It has become.

When the pressure sensor for detecting the relative pressure as described above is formed in the semiconductor chip 30, it is necessary that the space on the front surface 31 side and the space on the back surface 32 side of the substrate 10 are completely separated. In other words, the semiconductor chip 30 needs to be bonded to the substrate 10 by the adhesive 20 provided on the back surface 32 of the substrate 10 so as to go around the diaphragm 35. When the entire adhesive 20 is temporarily cured at the same timing at a time, a leak path 25 occurs because a part of the adhesive 20 cannot secure a bonding area with the substrate 10 as shown in FIG. Resulting in. Thereby, there is a possibility that the relative pressure cannot be measured accurately.

However, by delaying the timing of temporary curing of a part of the adhesive 20 as in the present invention, as shown in FIG. 21A, the circumference of the diaphragm 35 of the semiconductor chip 30 can be interrupted once around the substrate 10. It is possible to join with the adhesive 20 without any problem. That is, the leak path 25 can be eliminated, and the space on the front surface 31 side and the space on the back surface 32 side of the substrate 10 can be completely separated. Therefore, the relative pressure can be reliably detected in the pressure sensor.

(Twelfth embodiment)
In the present embodiment, parts different from the eleventh embodiment will be described. In the present embodiment, the capsule 23 mixed in the adhesive 20 is mechanically destroyed in the mounting process.

Specifically, as shown in FIG. 22, a substrate 10 whose mounting surface is not mirror-finished is prepared. That is, the mounting surface of the substrate 10 has an uneven shape 12. In order to easily destroy the capsule 23, the uneven shape 12 of the substrate 10 may be positively formed. Further, the uneven shape 12 may be formed at least at a position on the substrate 10 where the semiconductor chip 30 is mounted.

Then, as shown in FIG. 22, the substrate 10 is vibrated by applying a load of the substrate 10 to the temporarily cured adhesive 20. Thereby, the capsule 23 is broken by the uneven shape 12 of the substrate 10. In this case, the capsule 23 located on the surface side of the temporarily cured adhesive 20 is mainly destroyed.

As described above, the capsule 23 can be mechanically broken by the uneven shape 12 of the substrate 10. Note that a resin that is easily broken mechanically may be selected as the material of the capsule 23. Further, not the substrate 10 but the semiconductor chip 30 may be vibrated.

(13th Embodiment)
In the present embodiment, parts different from the eleventh and twelfth embodiments will be described. In the present embodiment, the capsule 23 mixed in the adhesive 20 is chemically destroyed in the mounting process.

Specifically, since acrylic resin is used as the shell of the capsule 23 as described above, as shown in FIG. 23, an organic solvent 13 such as acetone that can dissolve the acrylic resin on the mounting surface of the substrate 10. Prepare the one coated with. Of course, when another resin is used as the shell of the capsule 23, the organic solvent 13 capable of dissolving the resin may be applied to the mounting surface of the substrate 10.

Then, as shown in FIG. 23, by pressing the substrate 10 against the temporarily cured adhesive 20, the capsule 23 is melted and broken by the organic solvent 13. In this case, the capsule 23 located on the surface of the temporarily cured adhesive 20 is destroyed.

As described above, the capsule 23 can be chemically broken by melting the capsule 23. The semiconductor chip 30 may be moved to the substrate 10 side and the organic solvent 13 may be brought into contact with the capsule 23.

(Other embodiments)
The configurations of the semiconductor devices described in the above embodiments are examples, and the present invention is not limited to the configurations described above, and other configurations that can realize the present invention may be employed. For example, the configuration of the semiconductor device described in each of the above embodiments is a minimum configuration, and the semiconductor device may be mounted on another substrate, a package, or the like. In addition, when a plurality of semiconductor chips 30 are stacked, the semiconductor chips 30 that are diced and cut by providing the adhesive 20 on the semiconductor wafer 40 as described above may be stacked in order.

The capsules 23 shown in the eleventh to thirteenth embodiments may be used for the adhesive 20 in the second to tenth embodiments. Moreover, the method of destroying the capsule 23 is an example. Therefore, for example, the capsule 23 may be destroyed by heating with a laser or a liquid other than the organic solvent 13.

Although the present disclosure has been described based on the embodiments, it is understood that the present disclosure is not limited to the embodiments and structures. The present disclosure includes various modifications and modifications within the equivalent range. In addition, various combinations and forms, as well as other combinations and forms including only one element, more or less, are within the scope and spirit of the present disclosure.

Claims

Prepare a semiconductor wafer (40),
Placing an adhesive (20) at a predetermined position on one surface (41) of the semiconductor wafer (40);
The semiconductor wafer (40) is divided into individual semiconductor chips (30) by dicing the semiconductor wafer (40),
A substrate (10) is prepared, and the semiconductor chip (30) is mounted on the substrate (10) via the adhesive (20).
Having to temporarily cure the adhesive (20);
The temporary curing of the adhesive is performed before the placement of the adhesive or after the placement of the adhesive,
The method of manufacturing a semiconductor device, wherein the adhesive is temporarily cured before the dicing cut.
The method for manufacturing a semiconductor device according to claim 1, further comprising covering a portion of the adhesive (20) that does not contact the semiconductor wafer (40) with a cover film (52).
Covering with the cover film is performed after the placement of the adhesive, after the temporary curing of the adhesive, and before the dicing cut,
The cover film (52) covers the adhesive (20), and a region of the semiconductor wafer (40) where the adhesive (20) is not disposed is defined by the cover film (52). The method for manufacturing a semiconductor device according to claim 2, wherein the semiconductor device is covered.
Before placement of the adhesive and before the temporary curing of the adhesive, covering with the cover film,
After covering with the cover film, perform temporary curing of the adhesive,
After the temporary curing of the adhesive, the adhesive is disposed, and the area where the adhesive (20) is not disposed in one surface (41) of the semiconductor wafer (40) is defined by the cover film (52). The method for manufacturing a semiconductor device according to claim 2, wherein the semiconductor device is covered.
Before placement of the adhesive and before the temporary curing of the adhesive, covering with the cover film,
After covering with the cover film, placing the adhesive,
Covering the area where the adhesive (20) is not disposed on one surface (41) of the semiconductor wafer (40) with the cover film (52),
The method for manufacturing a semiconductor device according to claim 2, wherein the temporary curing step is performed after the placement of the adhesive.
The covering film (52) has a concavo-convex structure (57, 58) on a surface (55) on one surface (41) side of the semiconductor wafer (40) in covering with the cover film. The manufacturing method of the semiconductor device as described in any one.
In the dicing cut, the semiconductor wafer (40) is diced from the other surface (42) side opposite to the one surface (41) of the semiconductor wafer (40), and the cover film (52) is half-cut. A method for manufacturing a semiconductor device according to claim 2.
The method for manufacturing a semiconductor device according to any one of claims 2 to 6, wherein in the dicing cut, the cover film (52) and the semiconductor wafer (40) are diced and cut from the cover film (52) side.
After the placement of the adhesive and the temporary curing of the adhesive, before the dicing cut, in the area where the adhesive (20) is not disposed in one surface (41) of the semiconductor wafer (40), Further comprising disposing a protective material (60) harder than the adhesive (20),
The method of manufacturing a semiconductor device according to claim 1, wherein, in the dicing cut, the semiconductor wafer (40) is diced and cut in a state where the protective material (60) is disposed on one surface (41) of the semiconductor wafer (40). .
10. The semiconductor according to claim 9, wherein the mounting of the semiconductor chip (30) is performed by mounting the semiconductor chip (30) on the substrate (10) while leaving the protective material (60) on the semiconductor chip (30). Device manufacturing method.
The method for manufacturing a semiconductor device according to any one of claims 1 to 10, wherein the adhesive (20) is screen-printed in the placement of the adhesive.
In the temporary curing of the adhesive, a part of the adhesive (20) is temporarily cured,
In the mounting of the semiconductor chip, the semiconductor chip (30) is attached to the substrate (10) via a portion of the adhesive (20) that has been temporarily cured by the temporary curing of the adhesive and a portion that has not been temporarily cured. The method for manufacturing a semiconductor device according to claim 1, wherein the method is mounted.
In the arrangement of the adhesive, a part of the adhesive (20) is enclosed in a capsule (23),
In the temporary curing of the adhesive, the other part of the adhesive located outside the capsule (23) is temporarily cured,
In the mounting of the semiconductor chip, the capsule (23) is destroyed and the adhesive (20) enclosed in the capsule (23) and the adhesive (20) temporarily cured by temporary curing of the adhesive, The method of manufacturing a semiconductor device according to claim 12, wherein the semiconductor chip (30) is mounted on the substrate (10).
14. The adhesive (20) according to any one of claims 1 to 13, wherein the adhesive (20) is arranged such that a planar pattern of the adhesive (20) is one of a circle, a cross, and a polygon. In particular, a method for manufacturing a semiconductor device.
The adhesive (20) has an opening (21) that exposes one surface (41) of the semiconductor wafer (40),
In the arrangement of the adhesive, the adhesive is arranged on one surface (41) of the semiconductor wafer (40), and the conductive adhesive (22) is arranged in the opening (21).
The mounting of the semiconductor chip according to any one of claims 1 to 14, wherein the semiconductor chip (30) and the substrate (10) are electrically connected via the conductive adhesive (22). A method for manufacturing a semiconductor device.
The method for manufacturing a semiconductor device according to any one of claims 1 to 15, wherein in the arrangement of the adhesive, the adhesive (20) is a silicone-based adhesive.