JP7438740B2 - semiconductor process sheet - Google Patents

Description

The present invention relates to a semiconductor process sheet that can be used for manufacturing semiconductor packages.

Conventionally, in the manufacture of so-called semiconductor packages that have semiconductor elements inside, each semiconductor element is sealed with a resin material, and wiring and external electrodes that are electrically connected to the semiconductor element inside the encapsulation resin are manufactured. may be formed on the surface of the sealing resin. The manufacturing technology for semiconductor packages is described, for example, in Patent Document 1 below.

JP2017-88782A

In the process of manufacturing a semiconductor package, performing a sealing process, a wiring formation process, etc. for each element tends to complicate the process of manufacturing the semiconductor package and increase costs. As semiconductor packages become smaller and more densely packed, resulting in finer wiring and more terminals, the impact of performing encapsulation and wiring formation processes for each element on manufacturing costs becomes greater. There is a tendency.

In recent years, semiconductor packages called so-called fan-out wafer level packages (WLP) and fan-out panel level packages (PLP) have sometimes been adopted. In manufacturing these semiconductor packages, a sealing process and a wiring forming process are not performed for each semiconductor element, but are performed for a plurality of semiconductor elements all at once. In such a sealing process, for example, a plurality of semiconductor elements are placed on an adhesive sheet, a sealant is poured onto the adhesive sheet so as to cover the plurality of semiconductor elements, and then the sealant is cured.

However, when performing the sealing process on a plurality of semiconductor elements at once, there are problems in that the semiconductor elements move during the sealing process and subsequent processes, and the resulting semiconductor package is warped. It is presumed that warpage in the sealing process occurs when the sealant is cured and shrunk due to the large difference in linear expansion coefficient between the sealant and the pressure-sensitive adhesive sheet. Therefore, one way to suppress warpage is to peel off the adhesive sheet before curing the encapsulant, replace it with a warp prevention sheet whose coefficient of linear expansion is similar to that of the encapsulant, and then perform the curing process. Conceivable. However, the effort required to replace the adhesive sheet with a warp prevention sheet increases.

The present invention was conceived under these circumstances, and its purpose is to provide a semiconductor process sheet suitable for efficiently manufacturing semiconductor packages in which movement and warpage of semiconductor chips are suppressed. It is about providing.

As a result of intensive studies to achieve the above object, the present inventors have found that a double-sided pressure-sensitive adhesive sheet having a laminated structure including at least a reduced-adhesive pressure-sensitive adhesive layer, a pressure-sensitive adhesive layer, and a base material located between these; a thermosetting resin layer that is removably adhered to at least one adhesive surface of the double-sided adhesive sheet, and in at least one point in an uncured state or a cured state, the silicone of the thermosetting resin layer By using a semiconductor process sheet whose peeling force is at least a specific value and which is greater than the peeling force of the thermosetting resin layer to the double-sided adhesive sheet, it is possible to efficiently produce a semiconductor package in which movement and warpage of semiconductor chips are suppressed. It has been found that it can be easily manufactured. The present invention was completed based on these findings.

That is, the present invention provides a double-sided pressure-sensitive adhesive sheet having a laminated structure including at least a reduced-adhesive pressure-sensitive adhesive layer, a pressure-sensitive adhesive layer, and a base material located between these, and a double-sided pressure-sensitive adhesive sheet on at least one adhesive surface of the double-sided pressure-sensitive adhesive sheet. a thermosetting resin layer that is removably adhered to the
A semiconductor process sheet characterized in that the following first peel force is 5N or more in at least one uncured state or hardened state, and the following first peel force is larger than the following second peel force. I will provide a.
First peeling force: Peeling force of the thermosetting resin layer against the silicone in a peel test at a peeling angle of 180°.Second peeling force: Peeling force of the thermosetting resin layer against the double-sided pressure-sensitive adhesive sheet at a peeling angle of 180°. Peel force in peel test under conditions of

The semiconductor process sheet of the present invention includes a double-sided adhesive sheet and a thermosetting resin layer. The double-sided pressure-sensitive adhesive sheet has a laminated structure including at least a reduced-adhesive pressure-sensitive adhesive layer, a pressure-sensitive adhesive layer, and a base material located between these layers. The thermosetting resin layer is releasably adhered to at least one adhesive surface of the double-sided adhesive sheet. The present semiconductor process sheet having such a configuration can be used in the manufacturing process of semiconductor packages.

The semiconductor process sheet of the present invention is characterized in that the first peeling force is 5N or more, and the first peeling force is larger than the second peeling force. Regarding the peeling force of a pressure-sensitive adhesive sheet including a pressure-sensitive adhesive made of resin, it is generally said that the peeling force against resin and the peeling force against silicone are approximately the same, or the peeling force against resin is higher. Therefore, the second peeling force is an index representing the peeling force of the double-sided pressure-sensitive adhesive sheet to silicon. In other words, the peeling force of the thermosetting resin layer against silicon is higher than the peeling force of the thermosetting resin layer against the adhesive surface of the double-sided adhesive sheet. It can be shown that the peel force is higher than the peel force. By having at least one substantially uncured state or hardened state, by using the semiconductor process sheet of the present invention, semiconductor chips (semiconductor elements) can be formed on the double-sided pressure-sensitive adhesive sheet in the above-mentioned at least one state. The thermosetting resin layer has sufficient force to fix (temporarily fix) the semiconductor chip, compared to when fixing the semiconductor chip on the resin layer or on the resin layer, which has a weaker peeling force against silicone than the double-sided adhesive sheet. Therefore, movement of the semiconductor chip (so-called "chip shift") during the sealing process or after the sealing process can be suppressed or prevented. In particular, by curing the thermosetting resin layer to a hardened state, chip shift can be further suppressed or prevented during the sealing process and the like. In addition, after the thermosetting resin layer is cured, warping after sealing is suppressed or prevented by adjusting so that the curing shrinkage of the thermosetting resin layer cancels out the occurrence of warpage due to curing shrinkage of the sealing resin. be able to.

In addition, by configuring such a thermosetting resin layer to be peelably adhered to at least one adhesive surface of the double-sided adhesive sheet in advance, the thermosetting resin layer can be used to temporarily fix the semiconductor chip to the double-sided adhesive sheet. Since it can be used with a resin layer provided, there is no need for a separate step of using a thermosetting resin layer, and there is also no need for a step of replacing it with a warp prevention sheet before the sealing step. Therefore, by using the semiconductor process sheet of the present invention, semiconductor packages can be efficiently manufactured.

Note that the second peeling force of the thermosetting resin layer against the double-sided pressure-sensitive adhesive sheet in the substantially uncured or cured state at at least one point is the peeling force of the double-sided pressure-sensitive adhesive sheet against the thermosetting resin layer in the above-mentioned at least one state. It is essentially the same as power.

Further, in the double-sided pressure-sensitive adhesive sheet, it is preferable that the pressure-reduced adhesive layer is a heat-foaming pressure-sensitive adhesive layer, and the pressure-sensitive adhesive layer is a non-reduced pressure-sensitive adhesive layer. The heat-foamable pressure-sensitive adhesive layer can be easily peeled off from the adherend by foaming upon heating, while the non-adhesive force-reducing pressure-sensitive adhesive layer does not foam upon heating. In this way, when the semiconductor process sheet of the present invention has a heat-foamable adhesive layer on one side of a double-sided adhesive sheet, the thermosetting resin layer can be supported by being attached to an adherend such as a support through the double-sided adhesive sheet. Even if the thermosetting resin layer is peeled off from the adherend, the thermosetting resin layer can be easily peeled off from the adherend.

Further, in the semiconductor process sheet of the present invention, it is preferable that the ratio of the first peeling force to the second peeling force is 2 or more. According to the semiconductor process sheet of the present invention having such a configuration, the thermosetting resin layer in the at least one state has a peeling force against silicon that is sufficiently higher than the peeling force against the adhesive surface of the double-sided adhesive sheet. In order to demonstrate the above-mentioned at least The semiconductor chip can be more firmly fixed in a single point state, and movement of the semiconductor chip during the sealing process and thereafter can be further suppressed.

Furthermore, the semiconductor process sheet of the present invention is provided before a sealing step in which a sealing material is supplied so as to embed the semiconductor chip placed on the thermosetting resin layer, and then the sealing material is cured. Furthermore, it may be used for semi-curing or curing the thermosetting resin layer. It is preferable that the semi-curing or curing is performed by placing a semiconductor chip on the thermosetting resin layer so that the first peeling force is 5N or more.

According to the semiconductor process sheet of the present invention, in the production of semiconductor packages, the movement of semiconductor chips and the warping of semiconductor packages during the sealing process and subsequent sealing process when a plurality of semiconductor chips are collectively sealed with sealing resin can be efficiently reduced. Can be well controlled.

FIG. 1 is a schematic partial cross-sectional view of a semiconductor process sheet according to one embodiment of the present invention. 2 illustrates some steps in a semiconductor package manufacturing method in which the semiconductor process sheet shown in FIG. 1 is used. 2 illustrates some steps in a semiconductor package manufacturing method in which the semiconductor process sheet shown in FIG. 1 is used. 2 illustrates some steps in a semiconductor package manufacturing method in which the semiconductor process sheet shown in FIG. 1 is used. 2 illustrates some steps in a semiconductor package manufacturing method in which the semiconductor process sheet shown in FIG. 1 is used. 2 illustrates some steps in a semiconductor package manufacturing method in which the semiconductor process sheet shown in FIG. 1 is used. 2 illustrates some steps in a semiconductor package manufacturing method in which the semiconductor process sheet shown in FIG. 1 is used.

[Semiconductor process sheet]
The semiconductor process sheet of the present invention includes a double-sided adhesive sheet having a laminated structure including at least a reduced-adhesive adhesive layer, an adhesive layer, and a base material located between these, and at least one adhesive in the double-sided adhesive sheet. and a thermosetting resin layer that is removably adhered to the surface. An embodiment of the semiconductor process sheet of the present invention will be described below.

FIG. 1 is a schematic cross-sectional view showing one embodiment of a semiconductor process sheet of the present invention. As shown in FIG. 1, the semiconductor process sheet X can be used in the manufacturing process of semiconductor packages, and includes a double-sided adhesive sheet 10 and a thermosetting resin layer 20. The double-sided adhesive sheet 10 has an adhesive surface 10a and an opposite adhesive surface 10b, and between these adhesive surfaces 10a and 10b, a base material 11, an adhesive layer 12 of reduced adhesive strength, and an adhesive layer are formed. It has a laminated structure including 13. The thermosetting resin layer 20 is releasably adhered to the adhesive surface 10b of the double-sided adhesive sheet 10.

In the embodiment shown in FIG. 1, as described above, the adhesive layer 12, which is a reduced-adhesive adhesive layer, is located closer to the adhesive surface 10a than the base material 11, and the adhesive layer 13 is located closer to the adhesive surface 10a than the base material 11. It is located closer to the adhesive surface 10b than the adhesive surface 10b. Regarding the double-sided adhesive sheet 10 of the semiconductor process sheet It may be located on the surface 10b side.

Further, in the embodiment shown in FIG. 1, as described above, the thermosetting resin layer 20 is in close contact with the adhesive surface 10b provided by the adhesive layer 13 of the double-sided adhesive sheet 10 in a releasable manner, and has adhesive strength. An adhesive layer 12, which is a reduced adhesive layer, is located on the adhesive surface 10a side. With such a configuration, the adhesive layer 12 can be easily peeled off from the support or the like when a treatment for reducing the adhesive force of the adhesive layer 12 is performed. Further, the influence on the thermosetting resin layer 20 when the above treatment is performed can also be suppressed. Furthermore, the support can be efficiently recovered after the sealing step.

The semiconductor process sheet of the present invention has the following first peeling force of 5N or more in at least one uncured state or hardened state, and the following first peeling force is larger than the following second peeling force. It is characterized by
First peeling force: Peeling force of the thermosetting resin layer against the silicone in a peel test at a peeling angle of 180°.Second peeling force: Peeling force of the thermosetting resin layer against the double-sided adhesive sheet at a peeling angle of 180°. Peel force in peel test under conditions of

Regarding the peeling force of a pressure-sensitive adhesive sheet including a pressure-sensitive adhesive made of resin, it is generally said that the peeling force against resin and the peeling force against silicone are approximately the same, or the peeling force against resin is higher. Therefore, the second peeling force is an index representing the peeling force of the double-sided pressure-sensitive adhesive sheet to silicon. In other words, the peeling force of the thermosetting resin layer against silicon is higher than the peeling force of the thermosetting resin layer against the adhesive surface of the double-sided adhesive sheet. It can be shown that the peel force is higher than the peel force. By having at least one substantially uncured state or hardened state, by using the semiconductor process sheet of the present invention, semiconductor chips (semiconductor elements) can be formed on the double-sided pressure-sensitive adhesive sheet in the above-mentioned at least one state. The thermosetting resin layer has sufficient force to fix (temporarily fix) the semiconductor chip, compared to when fixing the semiconductor chip on the resin layer or on the resin layer, which has a weaker peeling force against silicone than the double-sided adhesive sheet. Therefore, movement of the semiconductor chip (so-called "chip shift") during the sealing process or after the sealing process can be suppressed or prevented. In particular, by curing the thermosetting resin layer, chip shift can be further suppressed or prevented during the sealing process and the like. In addition, after the thermosetting resin layer is cured, warping after sealing is suppressed or prevented by adjusting so that the curing shrinkage of the thermosetting resin layer cancels out the occurrence of warpage due to curing shrinkage of the sealing resin. be able to.

In addition, by configuring such a thermosetting resin layer to be peelably adhered to at least one adhesive surface of the double-sided adhesive sheet in advance, the thermosetting resin layer can be used to temporarily fix the semiconductor chip to the double-sided adhesive sheet. Since it can be used with a resin layer provided, there is no need for a separate step of using a thermosetting resin layer, and there is also no need for a step of replacing it with a warp prevention sheet before the sealing step. Therefore, by using the semiconductor process sheet of the present invention, semiconductor packages can be efficiently manufactured.

The second peeling force of the thermosetting resin layer to the double-sided pressure-sensitive adhesive sheet in the substantially uncured state or cured state at the at least one point is the The peeling force is substantially the same as the peeling force for the thermosetting resin layer in the state (the thermosetting resin layer in an uncured state or a hardened state with approximately the same degree of curing as the degree of curing of the thermosetting resin layer in the second peeling force). .

In this specification, the peeling force of the thermosetting resin layer against silicon in the above-mentioned at least one state in a peeling test under the condition of a peeling angle of 180° is referred to as the "first peeling force", and the above-mentioned peeling force in the above-mentioned cured state The peeling force of the thermosetting resin layer against silicon may be referred to as "third peeling force". Therefore, the first peeling force may be the same or comparable in magnitude to the third peeling force. Further, the peeling force of the thermosetting resin layer in the above-mentioned at least one state with respect to the double-sided pressure-sensitive adhesive sheet in a peeling test under the condition of a peeling angle of 180° may be referred to as "second peeling force".

In the first peeling force and the second peeling force, a substantially uncured state means that the thermosetting resin layer is not cured or partially cured so that the degree of curing is less than 90%. This refers to the hardened state. On the other hand, in the first peel force, the second peel force, and the third peel force, the substantially cured state refers to a partially cured state with a degree of cure of 90% or more, or a completely cured state. This refers to the hardened state. In the semiconductor process sheet of the present invention, the thermosetting resin has a first peel force of 5 N or more in at least one of a substantially uncured state and a substantially cured state, and the first peel force has a second peel force. It should be greater than the force. Note that the first peel force and the second peel force are applied to the same thermosetting resin layer, including the degree of hardening (for example, when the degree of hardening is less than 90% and the state is completely uncured or partially cured) , a thermosetting resin layer having the same degree of curing). Further, the second peeling force may be applied to at least one adhesive surface of the double-sided adhesive sheet, but in the semiconductor process sheet of the present invention, the first peeling force is applied to both adhesive surfaces of the double-sided adhesive sheet. It is preferable that the peeling force is larger than the second peeling force. Note that the degree of curing of the thermosetting resin layer is calculated as the ratio of the calorific value to the calorific value in a state where no curing treatment is actively performed.

The first peel force and the second peel force are not particularly limited as long as they are peel forces measured under the same conditions, but a peel test was performed at 23°C, a peel angle of 180°, and a tensile speed of 300 mm/min. It is important that the peeling force is at . The first peel force and the second peel force can be measured using a tensile tester (trade name "Autograph AG-X", manufactured by Shimadzu Corporation). Specifically, the method for preparing the test piece used for the measurement and the measurement method are as follows.

In measuring the first peeling force, a test piece of the thermosetting resin layer with a size of 20 mm in width x 100 mm in length is cut out from the thermosetting resin layer. Next, one side of the test piece is bonded to a silicon plate (the mirror side of a typical unground wafer). This bonding is performed by pressing a 2 kg hand roller back and forth once. Next, if necessary, the thermosetting resin layer is cured by heating to a desired degree of curing. Then, using a tensile testing machine (trade name "Autograph AG-X", manufactured by Shimadzu Corporation), the test piece was subjected to a peel test at 23°C, a peel angle of 180°, and a tensile speed of 300 mm/min. The peeling force (first peeling force) of the thermosetting resin layer against the silicon plate in an uncured state or a cured state is measured.

To measure the second peeling force, a test piece with a size of 20 mm width x 100 mm length is cut out from the semiconductor process sheet. Next, if necessary, the thermosetting resin layer is cured by heating to a desired degree of curing. In addition, when curing the thermosetting resin layer, the degree of curing of the curable resin layer at the second peeling force is the same or approximately the same as the degree of curing of the thermosetting resin layer at the time of measuring the first peeling force. degree). That is, in measuring the second peel force, the heating conditions for curing the thermosetting resin layer are the same or substantially the same as those for curing the thermosetting resin when measuring the first peel force. Then, using a tensile testing machine (trade name "Autograph AG-X", manufactured by Shimadzu Corporation), the test piece was subjected to a peel test at 23°C, a peel angle of 180°, and a tensile speed of 300 mm/min. The peeling force (second peeling force) of the thermosetting resin layer against the adhesive surface of the double-sided adhesive sheet in an uncured state or a cured state is measured.

The above-mentioned third peel force is not particularly limited as long as it is a peel force measured under the same conditions as the first peel force and the second peel force. What is important is the peel force in the peel test. The third peel force can be measured using a tensile tester (trade name "Autograph AG-X", manufactured by Shimadzu Corporation). Specifically, the method for preparing the test piece used for the measurement and the measurement method are as follows.

To measure the third peeling force, a test piece with a size of 20 mm width x 100 mm length is cut out from the thermosetting resin layer. Next, one side of the test piece is bonded to a silicon plate (the mirror side of a typical unground wafer). This bonding is performed by pressing a 2 kg hand roller back and forth once. Next, the thermosetting resin layer is cured by heating to a degree of curing of 90% or more. Then, using a tensile testing machine (trade name "Autograph AG-X", manufactured by Shimadzu Corporation), the test piece was subjected to a peel test at 23°C, a peel angle of 180°, and a tensile speed of 300 mm/min. The peeling force (third peeling force) of the thermosetting resin layer against the silicon plate in the cured state is measured.

Note that when the first peel force is the peel force in the cured state of the thermosetting resin layer, the first peel force and the third peel force are measured under the same or substantially the same conditions.

In the semiconductor process sheet of the present invention, the ratio of the first peeling force to the second peeling force is not particularly limited, but is preferably 2 or more, more preferably 10 or more, still more preferably 20 or more, and particularly preferably is 30 or more. If the above ratio is 2 or more, this indicates that the thermosetting resin layer in the above-mentioned at least one state has a sufficiently higher peeling force against silicon than the adhesive surface of the double-sided adhesive sheet, so the semiconductor chip or on a resin layer whose peeling force against silicon is weaker than that of the double-sided pressure-sensitive adhesive sheet, the semiconductor chip is more strongly fixed in the state of at least one point of the thermosetting resin layer. The semiconductor chip can be fixed (temporarily fixed) to the semiconductor chip, and movement of the semiconductor chip during the sealing process and thereafter can be further suppressed. Further, by such thermosetting of the thermosetting resin layer, it is possible to more appropriately adjust the occurrence of warpage due to curing shrinkage of the sealing resin so that the curing shrinkage of the thermosetting resin layer cancels it out. Thereby, warping can be further suppressed. The above ratio is preferably higher, but may be, for example, 100 or less, 90 or less, 80 or less, 70 or less.

In the semiconductor process sheet of the present invention, the first peeling force is 5N or more, preferably 6N or more, more preferably 7N or more, and still more preferably 8N or more. When the peeling force is 5 N or more, the semiconductor chip can be more firmly fixed (temporarily fixed), and movement of the semiconductor chip during the sealing process and thereafter can be further suppressed. The first peeling force is preferably as high as possible, and may be, for example, 50N or less, 30N or less, or 20N or less, but is usually 12N or less. Note that the above peeling force is a value at a width of 20 mm. Further, the first peeling force may be greater than the second peeling force and satisfied at any one point in the substantially uncured state and the substantially cured state.

The second peeling force is not particularly limited, but is preferably 0.05N or more, more preferably 0.1N or more. When the second peeling force is 0.05 N or more, unintended peeling between the thermosetting resin layer and the double-sided pressure-sensitive adhesive sheet can be suppressed. The second peeling force is not particularly limited, but is preferably 3N or less, more preferably 1N or less, even more preferably 0.5N or less. When the second peeling force is 3 N or less, the double-sided adhesive sheet can be easily peeled off after the semiconductor chip sealing process. Note that the above peeling force is a value at a width of 20 mm.

In the semiconductor process sheet of the present invention, the peeling force of the thermosetting resin layer against silicon in the cured state is not particularly limited, but is usually larger than the peeling force of the thermosetting resin layer against silicon in the uncured state. Specifically, in the semiconductor process sheet of the present invention, the third peeling force is 5N or more, preferably exceeds 5N, more preferably 6N or more, still more preferably 8N or more, even more preferably 10N or more, especially Preferably it is 12N or more. The third peeling force is preferably higher, but may be, for example, 50N or less, 30N or less, or 20N or less. When the third peeling force is 5N or more, the force for fixing the semiconductor chip in the cured state of the thermosetting resin layer is sufficient, so that movement of the semiconductor chip during the sealing process and thereafter can be further suppressed. . Further, after thermosetting, warping can be further suppressed by adjusting the occurrence of warpage due to curing shrinkage of the sealing resin so that curing shrinkage of the thermosetting resin layer cancels it out. Note that the above-mentioned third peeling force is a value at a width of 20 mm. Further, the third peeling force may be greater than the second peeling force as long as it is satisfied at any one point in the cured state.

In the semiconductor process sheet of the present invention, it is important that the first peel force and/or the third peel force are greater than the peel force of the double-sided pressure-sensitive adhesive sheet to silicon. By using the semiconductor process sheet of the present invention having such a configuration, it is possible to fix a semiconductor chip on a double-sided adhesive sheet, or on a resin layer whose peeling force against silicon is weaker than that of the double-sided adhesive sheet. Since the semiconductor chip can be more firmly fixed in the state of at least one point of the thermosetting resin layer compared to the case where the thermosetting resin layer is fixed (temporarily fixed) to the semiconductor chip, the thermosetting resin layer has sufficient force to fix (temporarily fix) the semiconductor chip. Therefore, it is possible to suppress the occurrence of warpage after thermosetting, and further suppress the movement of the semiconductor chip during the sealing process and thereafter. In addition, in this specification, the peeling force of the double-sided pressure-sensitive adhesive sheet to silicon may be referred to as "fourth peeling force."

The first peel force and the fourth peel force are not particularly limited as long as they are peel forces measured under the same conditions, but a peel test was conducted at 23°C, a peel angle of 180°, and a tensile speed of 300 mm/min. It is preferable that the peeling force is . The same applies to the third peeling force and the fourth peeling force. The fourth peel force can be measured using a tensile tester (trade name "Autograph AG-X", manufactured by Shimadzu Corporation). Specifically, the method for preparing the test piece used for the measurement and the measurement method are as follows.

To measure the fourth peeling force, a test piece with a size of 20 mm width x 100 mm length is cut out from the double-sided adhesive sheet. Next, the test piece is attached to a silicon plate (the mirror side of a typical unground wafer) using its adhesive side. This bonding is performed by pressing a 2 kg hand roller back and forth once. Then, using a tensile testing machine (trade name "Autograph AG-X", manufactured by Shimadzu Corporation), the test piece was subjected to a peel test at 23°C, a peel angle of 180°, and a tensile speed of 300 mm/min. The peeling force (fourth peeling force) of the adhesive side of the double-sided adhesive sheet against the silicon plate is measured.

In the semiconductor process sheet of the present invention, the shear adhesion of the thermosetting resin layer to silicon in the at least one state is the shear adhesion of the thermosetting resin layer to the double-sided adhesive sheet in the at least one state. It is preferable that it is larger than the force. Further, in the semiconductor process sheet of the present invention, the shear adhesive force of the thermosetting resin layer to silicon in the cured state is equal to the shear adhesive force of the thermosetting resin layer to the double-sided adhesive sheet in the at least one state. It is important that they have the same or larger size. By using the semiconductor process sheet of the present invention having such a configuration, it is provided with a thermosetting resin layer that has a higher shear adhesion force to silicon than the shear adhesion force to the adhesive surface of the double-sided adhesive sheet. Movement of the semiconductor chip in the shear direction during the process and thereafter can be further suppressed.

In the semiconductor process sheet of the present invention, it is preferable that the shear adhesive force of the thermosetting resin layer to silicon in the at least one state is greater than the shear adhesive force of the double-sided adhesive sheet to silicon. By using the semiconductor process sheet of the present invention having such a configuration, it is provided with a thermosetting resin layer that has a higher shear adhesion force to silicon than the adhesive surface of the double-sided adhesive sheet, so that the sealing process and subsequent The movement of the semiconductor chip in the shear direction can be further suppressed.

In the semiconductor process sheet of the present invention, the shear adhesive force (first shear adhesive force) of the thermosetting resin layer to silicon in the at least one state is not particularly limited, but is preferably 5 kg or more, more preferably 6 kg. The weight is more preferably 10 kg or more. When the first shear adhesive force is 5 kg or more, the semiconductor chip can be more firmly fixed (temporarily fixed), and movement of the semiconductor chip during the sealing process and thereafter can be further suppressed. The first shear adhesive strength is preferably as high as possible, but may be, for example, 70 kg or less, 50 kg or less, or 40 kg or less. Note that the first shear adhesive strength is a value for a thermosetting resin layer having a width of 3 mm and a length of 3 mm. Further, the first shear adhesive force is measured at the same or comparable degree of curing as the thermosetting resin layer in the at least one point state in the first peel force. That is, the first shear adhesive force and the first peel force cure the thermosetting resin under the same or substantially the same heating conditions.

The first shear adhesive strength is measured as follows. A thermosetting resin layer having a size of 3 mm in width x 3 mm in length is cut out from the thermosetting resin layer. In addition, a silicon plate (width 10 mm x length 10 mm) was prepared from a silicon plate (mirror surface side of a general unground wafer, thickness 500 μm), and silicon chips cut into pieces of 3 mm width x 3 mm length were prepared. do. Then, the cut out thermosetting resin layer and the silicon chip cut into pieces of 3 mm width x 3 mm length were bonded together under conditions of a temperature of 70°C and a pressure of 0.5 MPa, so that the thermosetting resin layer and the silicon chip were bonded together. A laminated test piece (width 3 mm x length 3 mm) is prepared. The above test piece was pasted onto a silicon plate (thickness 500 μm x width 10 mm x width 10 mm) placed on a hot plate (70°C) so that the surface on the thermosetting resin layer side was in contact. Press to crimp. Next, if necessary, the thermosetting resin layer is cured by heating to a desired degree of curing. Then, this laminate of silicon plate/thermosetting resin layer/silicon chip was set in a shear adhesion measuring device (product name "DAGE4000", manufactured by Nordson), and a jig was placed at a temperature of 23°C. The jig was moved while pushing the silicon chip at a height of 80 μm at the bottom surface (height from the silicon plate), a speed of 500 μm/sec, and a movement amount of 500 μm to determine the thermosetting properties at at least one point above. Measure the shear adhesive strength of the resin layer.

In the semiconductor process sheet of the present invention, the shear adhesive force (second shear adhesive force) of the thermosetting resin layer to the double-sided adhesive sheet in the at least one state is not particularly limited, but is preferably 0.1 kg or more. , more preferably 0.5 kg or more, still more preferably 1 kg or more, particularly preferably 2 kg or more. When the second shear adhesive force is 0.1 kg or more, the force for fixing (temporarily fixing) the semiconductor chip on the thermosetting resin layer becomes more sufficient, so that the movement of the semiconductor chip during the sealing process and thereafter is more easily prevented. Can be suppressed. The second shear adhesive strength is preferably as high as possible, but may be, for example, 10 kg or less, 5 kg or less, or 3 kg or less. In addition, the said 2nd shear adhesive force is the value in the thermosetting resin layer of width 3mm x length 3mm. Further, the second shear adhesive force is measured at the same degree of curing as the thermosetting resin layer in the at least one point state in the first peel force.

The second shear adhesive strength is measured as follows. A double-sided adhesive sheet is pasted onto the silicon plate (thickness: 500 μm x width: 10 mm x width: 10 mm) prepared in the measurement of the first shear adhesive strength. Then, the test piece prepared in the first shear adhesive strength measurement is pasted onto the double-sided pressure-sensitive adhesive sheet in such a manner that the surface on the thermosetting resin layer side is in contact with the sheet, and pressed by hand to pressure-bond the sheet. Next, if necessary, the thermosetting resin layer is cured by heating to a desired degree of curing. Then, this laminate of silicone plate/double-sided adhesive sheet/thermosetting resin layer/silicon chip was set in a shear adhesion measuring device (trade name "DAGE4000", manufactured by Nordson) at a temperature of 23°C. Then, the jig was moved while pushing the silicon chip under the conditions that the height of the bottom surface of the jig was 80 μm (height from the double-sided adhesive sheet), the speed was 500 μm/sec, and the amount of movement was 500 μm, and the shear of the double-sided adhesive sheet was measured. Measure the adhesive strength.

In the semiconductor process sheet of the present invention, the shear adhesive force (third shear adhesive force) of the thermosetting resin layer to silicon in the cured state is not particularly limited, but is preferably 3 kg or more, more preferably 10 kg or more, and even more preferably is 20 kg or more, particularly preferably 30 kg or more. When the shear adhesive force is 3 kg or more, the force of the thermosetting resin layer to fix the semiconductor chip becomes more sufficient, so that movement of the semiconductor chip after the sealing process can be further suppressed. The third shear adhesive force is preferably as high as possible, but may be, for example, 50 kg or less. The above-mentioned third shear adhesive strength is a value for a thermosetting resin layer having a width of 3 mm and a length of 3 mm. Further, the third shear adhesive strength is measured at the same degree of curing as that of the thermosetting resin layer in the third peeling force.

The third shear adhesive strength is measured as follows. The silicon plate/thermosetting resin layer/silicon chip laminate prepared in the first shear adhesive strength measurement is heated to thermoset the thermosetting resin layer. Then, the laminate of silicon plate/cured thermosetting resin layer/silicon chip was set in a shear adhesion measuring device (trade name "DAGE4000", manufactured by Nordson) at a temperature of 23°C. The thermosetting resin in the cured state was measured by moving the jig while pushing the silicon chip under the following conditions: the height of the bottom surface of the jig was 80 μm (height from the silicon plate), the speed was 500 μm/sec, and the amount of movement was 500 μm. Measure the shear adhesion of the layers. In addition, when the first shear adhesive force is the peeling force of the thermosetting resin layer in the cured state, the first shear adhesive force and the third shear adhesive force are measured under the same or substantially the same conditions.

In the semiconductor process sheet of the present invention, the shear adhesive force (fourth shear adhesive force) to silicon of the double-sided adhesive sheet is not particularly limited, but is preferably 5 kg or less, more preferably 3 kg or less. When the fourth shear adhesive force is 5 kg or less, the double-sided adhesive sheet can be easily peeled off after the semiconductor chip sealing process. The fourth shear adhesive force may be, for example, 0.5 kg or more, or 1 kg or more. Note that the fourth shear adhesive force is a value for silicon having a width of 3 mm and a length of 3 mm.

The fourth shear adhesive strength is measured as follows. A double-sided adhesive sheet is pasted onto the silicon plate (thickness: 500 μm x width: 10 mm x width: 10 mm) prepared in the measurement of the first shear adhesive strength. Then, the silicon chip (thickness: 500 μm x width: 3 mm x width: 3 mm) prepared in the measurement of the first shear adhesive force is bonded onto the double-sided adhesive sheet and pressed by hand. This laminate of silicon plate/double-sided adhesive sheet/silicon chip was set in a shear adhesion measuring device (product name "DAGE4000", manufactured by Nordson), and the position of the bottom surface of the jig was measured at a temperature of 23°C. The shear adhesive force of the double-sided adhesive sheet is measured by moving the jig while pushing the silicon chip under the conditions of a height of 80 μm (height from the double-sided adhesive sheet), a speed of 500 μm/sec, and a movement amount of 500 μm.

In the semiconductor process sheet of the present invention, the misalignment distance of the semiconductor chip before and after thermosetting the thermosetting resin, measured by the following misalignment evaluation, is not particularly limited, but is preferably 150 μm or less, more preferably 100 μm or less. , more preferably 50 μm or less, particularly preferably 30 μm or less. Note that the lower limit value of the misalignment distance of the semiconductor chip is preferably zero.
<Positional deviation evaluation>
The adhesive layer side of a semiconductor process sheet with a thermosetting resin layer is attached to a silicon plate (mirror side of a general unground wafer) to create a laminate of silicon plate/double-sided adhesive sheet/thermosetting resin layer. do. Chips (silicon chips cut into pieces of 10 mm width x 10 mm length; thickness 100 μm) are placed in the thermosetting resin layer of the laminate at the center of the laminate and at a distance of 70 mm from each side of the chip in the center. Paste it in 4 places. Then, if necessary, the laminate is heated to harden the thermosetting resin layer. Then, the coordinates of each chip are determined from the surface on which the chips are pasted together, and the position of this chip is set as the initial position. Thereafter, the chip is sealed using a sealing sheet (200 μm) and thermally cured at 150° C. for 1 hour to obtain a sealed cured object. [Thermosetting resin layer/chip/sealing layer] is peeled off from this sealed cured object, and the thermosetting resin layer is removed by polishing to expose the surface of the chip. Thereafter, the coordinates of each chip are determined from the chip exposed surface side, and the position of this chip is determined as the position after sealing and curing. Then, the average value of the distances that the chips have moved from the initial position to the post-sealing and curing position for the four chips away from the center is defined as the positional deviation distance.

In the semiconductor process sheet of the present invention, the amount of warpage correction measured by the following warpage correction amount evaluation of the thermosetting resin layer may be an amount corresponding to the amount of warpage of the sealing material (sealing sheet, etc.), It is important to set it appropriately depending on the type of sealing material. Note that the specific value can be set as appropriate, for example, from a range of 1 to 20 mm.
<Evaluation of warpage correction amount>
A silicon plate (general unground wafer) is ground with #2000 finish to a thickness of 200 μm, and a thermosetting resin layer (40 μm thick) is bonded to the ground side to form a disc-shaped silicon plate with a diameter of 300 mm/heat. A laminate of curable resin layers is produced. The laminate is heated in an oven at 130° C. for 2 hours to cure the thermosetting resin layer. Thereafter, the laminate is left on a flat table at room temperature for 1 hour with the thermosetting resin layer facing upward. Thereafter, the distance between the outer peripheral portion of the disc of the laminate and the flat surface on the flat table is measured, and the distance with the greatest difference (the largest) is determined as the amount of warpage correction.

In the semiconductor process sheet of the present invention, it is preferable that the glass transition temperature (Tg) of the thermosetting resin layer is equal to or higher than the molding temperature of the semiconductor element encapsulant or equal to or higher than 120°C. In this case, during the molding of the encapsulant that seals the semiconductor element such as a semiconductor chip, the flow of the thermosetting resin layer is suppressed and the semiconductor element is firmly fixed. Chip shift can be further suppressed or prevented. In addition, after the thermosetting resin layer is cured, the warping caused by the curing shrinkage of the sealing resin is adjusted to be canceled out by the curing shrinkage of the thermosetting resin layer, thereby further suppressing or preventing warping after sealing. can do.

The glass transition temperature of the thermosetting resin layer is not particularly limited, but is preferably 120°C or higher, more preferably 130°C or higher, and still more preferably 150°C or higher. When the glass transition temperature is 120° C. or higher, movement of the semiconductor element during the sealing process and thereafter can be further suppressed. The upper limit of the glass transition temperature may be within a range that maintains tackiness before and after curing, and is, for example, 200°C. The glass transition temperature can be calculated using a dynamic mechanical analysis (DMA) device.

In the semiconductor process sheet of the present invention, the tack force of the thermosetting resin layer is preferably 200 g or more, more preferably 300 g or more, and still more preferably 400 g or more. When the tack force is 200 g or more, the thermosetting resin layer has sufficient force to fix the semiconductor element, so that movement of the semiconductor element during the sealing process and after the sealing process can be further suppressed. The above tack force is calculated by pressing the SUS plate for 1 second so that a load of 100 g is applied to the thermosetting resin layer at a temperature of 40°C, and then lifting the SUS plate to the top and pulling it apart. It can be obtained as the load value applied to the SUS plate when the curable resin sheet is peeled off.

The curing start temperature of the thermosetting resin layer is not particularly limited, but is preferably 120 to 180°C, more preferably 130 to 150°C. When the curing start temperature is within the above range, the thermosetting resin layer can be effectively cured to a desired degree of curing (for example, without expanding the heat-foamable adhesive layer) before the sealing process. Therefore, movement of the semiconductor element after the sealing process can be further suppressed. The curing start temperature is determined by differential scanning calorimetry (DSC) measurement using the rising temperature of the exothermic peak as the reaction start temperature.

In the semiconductor process sheet of the present invention, the elastic modulus of the thermosetting resin layer in the at least partially cured state is not particularly limited, but is preferably 2000 Pa or more, more preferably 2500 Pa or more, and even more preferably 3000 Pa or more. . The elastic modulus is preferably 10,000 Pa or less, more preferably 7,000 Pa or less. When the elastic modulus is 2000 Pa or more (particularly within the above range), it is possible to more easily adjust the occurrence of warpage due to curing shrinkage of the sealing material in the sealing process so that the curing shrinkage of the thermosetting resin layer cancels it out. It is possible to suppress or prevent warping after sealing. The above-mentioned elastic modulus is determined as a storage elastic modulus E' at 25° C. by dynamic viscoelasticity (DMA) measurement.

(Base material)
The base material in a double-sided adhesive sheet is an element that functions as a support in a double-sided adhesive sheet or a semiconductor process sheet. Examples of the base material include plastic base materials (especially plastic films). The base material may be a single layer or a laminate of base materials of the same type or different types.

Examples of the resin constituting the plastic base material include low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, ultra-low-density polyethylene, random copolymerized polypropylene, block copolymerized polypropylene, and homopolyprolene. , polybutene, polymethylpentene, ethylene-vinyl acetate copolymer (EVA), ionomer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid ester (random, alternating) copolymer, ethylene- Polyolefin resins such as butene copolymers and ethylene-hexene copolymers; polyurethanes; polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate, and polybutylene terephthalate (PBT); polycarbonates; polyimides; polyether ether ketones; polyether imides ; polyamides such as aramid and wholly aromatic polyamide; polyphenylsulfide; fluororesin; polyvinyl chloride; polyvinylidene chloride; cellulose resin; silicone resin. The above resins may be used alone or in combination of two or more.

When the base material is a plastic film, the plastic film may be non-oriented or may be oriented in at least one direction (uniaxial direction, biaxial direction, etc.). The plastic film oriented in at least one direction can be obtained by stretching (uniaxial stretching, biaxial stretching, etc.) an unstretched plastic film in the at least one direction.

The surface of the base material is subjected to treatments such as corona discharge treatment, plasma treatment, sand mat treatment, ozone exposure treatment, flame exposure treatment, high-voltage electric shock exposure treatment, and ionization to improve adhesion and retention with the adhesive layer. Physical treatment such as radiation treatment; chemical treatment such as chromic acid treatment; surface treatment such as adhesion treatment using a coating agent (undercoating agent) may be performed. Further, in order to impart antistatic ability, a conductive vapor deposition layer containing a metal, an alloy, an oxide thereof, or the like may be provided on the surface of the base material. The surface treatment for improving adhesion is preferably applied to the entire surface of the base material on the pressure-sensitive adhesive layer side.

The thickness of the base material is preferably 5 μm or more, more preferably 10 μm or more, from the viewpoint of ensuring the strength for the base material to function as a support in a double-sided pressure-sensitive adhesive sheet and a semiconductor process sheet. Moreover, from the viewpoint of realizing appropriate flexibility in the double-sided pressure-sensitive adhesive sheet and the semiconductor process sheet, the thickness of the base material is preferably 300 μm or less, more preferably 200 μm or less.

(Adhesive layer with reduced adhesive strength)
The reduced adhesive force type adhesive layer is formed from a reduced adhesive force type adhesive. The adhesive layer with reduced adhesive strength may be, for example, an adhesive layer formed from a heat-foamable adhesive (heat-foamable adhesive layer), or an adhesive layer whose adhesive strength is such that it cannot be used in the semiconductor package manufacturing process due to radiation irradiation. Examples include an adhesive layer (radiation-curable adhesive layer) formed from a radiation-curable adhesive of a type (first type) in which the radiation curable temperature decreases to . In the above adhesive force-reducing adhesive layer, only one type of adhesive force-reducing adhesive may be used, or two or more types may be used.

The heat-foamable pressure-sensitive adhesive layer contains, for example, at least a main pressure-sensitive adhesive and a component that foams or expands when heated. When the foamable component or expandable component contained in the heat-foamable adhesive layer is sufficiently heated, it expands and produces an uneven shape on its surface (adhesive surface). When the heat-foamable adhesive layer is subjected to such heating while the adhesive surface is attached to the adherend, the adhesive layer expands and creates an uneven shape on the adhesive surface, causing the adhesive surface to become uneven. This results in a decrease in the total adhesion area to the adherend, and a decrease in adhesive strength to the adherend.

As the main adhesive for the heat-foaming adhesive layer, known or commonly used pressure-sensitive adhesives can be used, including acrylic adhesives based on acrylic polymers, rubber adhesives, and silicone adhesives. Examples include.

The above-mentioned acrylic polymer is a polymer containing, as a polymer structural unit, a structural unit derived from an acrylic monomer (a monomer component having a (meth)acryloyl group in the molecule).

It is preferable that the acrylic polymer is a polymer containing the largest amount of structural units derived from (meth)acrylic acid ester in mass proportion. In addition, only one type of acrylic polymer may be used, or two or more types may be used. Furthermore, in this specification, "(meth)acrylic" refers to "acrylic" and/or "methacrylic" (either or both of "acrylic" and "methacrylic"), and the same applies to the others. .

Examples of the above (meth)acrylic esters include hydrocarbon group-containing (meth)acrylic esters. Examples of the hydrocarbon group-containing (meth)acrylic ester include (meth)acrylic acid alkyl ester, (meth)acrylic acid cycloalkyl ester, (meth)acrylic acid aryl ester, and the like.

Examples of the (meth)acrylic acid alkyl ester include methyl ester, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, s-butyl ester, t-butyl ester, pentyl ester, Isopentyl ester, hexyl ester, heptyl ester, octyl ester, 2-ethylhexyl ester, isooctyl ester, nonyl ester, decyl ester, isodecyl ester, undecyl ester, dodecyl ester (lauryl ester), tridecyl ester, tetradecyl ester , hexadecyl ester, octadecyl ester, eicosyl ester, etc.

Examples of the above-mentioned (meth)acrylic acid cycloalkyl ester include cyclopentyl ester and cyclohexyl ester of (meth)acrylic acid. Examples of the (meth)acrylic acid aryl ester include phenyl ester and benzyl ester of (meth)acrylic acid.

The above hydrocarbon group-containing (meth)acrylic esters may be used alone or in combination of two or more.

In order to properly exhibit basic properties such as tackiness due to hydrocarbon group-containing (meth)acrylic acid ester in the adhesive layer, it is necessary to use hydrocarbon group-containing (meth)acrylate in all monomer components to form the acrylic polymer. The proportion of the acid ester is preferably 40% by mass or more, more preferably 60% by mass or more.

The acrylic polymer may contain a structural unit derived from another monomer component copolymerizable with the hydrocarbon group-containing (meth)acrylate ester for the purpose of modifying cohesive force, heat resistance, etc. . Examples of the other monomer components include polar groups such as carboxy group-containing monomers, acid anhydride monomers, hydroxy group-containing monomers, glycidyl group-containing monomers, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, and nitrogen atom-containing monomers. Examples include containing monomers.

Examples of the carboxy group-containing monomer include acrylic acid, methacrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. Examples of the acid anhydride monomer include maleic anhydride and itaconic anhydride.

Examples of the hydroxy group-containing monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, Examples include 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, and (4-hydroxymethylcyclohexyl)methyl (meth)acrylate.

Examples of the glycidyl group-containing monomer include glycidyl (meth)acrylate, methylglycidyl (meth)acrylate, and the like.

Examples of the sulfonic acid group-containing monomers include styrene sulfonic acid, allyl sulfonic acid, 2-(meth)acrylamido-2-methylpropanesulfonic acid, (meth)acrylamidopropanesulfonic acid, sulfopropyl (meth)acrylate, and (meth)acrylamidopropanesulfonic acid. ) Acryloyloxynaphthalene sulfonic acid and the like.

Examples of the phosphoric acid group-containing monomer include 2-hydroxyethyl acryloyl phosphate.

Examples of the nitrogen atom-containing monomer include morpholino group-containing monomers such as (meth)acryloylmorpholine, cyano group-containing monomers such as (meth)acrylonitrile, and amide group-containing monomers such as (meth)acrylamide.

The above-mentioned other monomer components may be used alone or in combination of two or more.

In order to properly exhibit basic properties such as adhesiveness due to hydrocarbon group-containing (meth)acrylic acid ester in the adhesive layer, the proportion of the polar group-containing monomer in the total monomer components for forming the acrylic polymer must be adjusted. is preferably 60% by mass or less, more preferably 50% by mass or less.

The acrylic polymer may contain a structural unit derived from a polyfunctional monomer copolymerizable with the monomer component forming the acrylic polymer in order to form a crosslinked structure in the polymer skeleton. Examples of the polyfunctional monomer include hexanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, and pentyl glycol di(meth)acrylate. Erythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, epoxy(meth)acrylate (e.g. polyglycidyl(meth)acrylate), polyester Examples include monomers having a (meth)acryloyl group and other reactive functional groups in the molecule, such as (meth)acrylate and urethane (meth)acrylate.

The above polyfunctional monomers may be used alone or in combination of two or more. In order to properly exhibit basic properties such as tackiness due to hydrocarbon group-containing (meth)acrylic acid ester in the adhesive layer, the proportion of the above-mentioned polyfunctional monomer in the total monomer components for forming the acrylic polymer must be adjusted. , is preferably 40% by mass or less, more preferably 30% by mass or less.

Acrylic polymers are obtained by subjecting one or more monomer components containing acrylic monomers to polymerization. Examples of polymerization methods include solution polymerization, emulsion polymerization, bulk polymerization, and suspension polymerization.

From the viewpoint of high cleanliness during the production of semiconductor packages in which the double-sided pressure-sensitive adhesive sheet and the semiconductor process sheet of the present invention are used, it is preferable that the amount of low molecular weight components in each pressure-sensitive adhesive layer in the double-sided pressure-sensitive adhesive sheet is small. Therefore, the number average molecular weight of the acrylic polymer is preferably 100,000 or more, more preferably 200,000 to 3,000,000. The number average molecular weight of an acrylic polymer depends on, for example, the polymerization method employed, the type and amount of polymerization initiator used, the temperature and time of the polymerization reaction, the concentration of various monomers in all monomer components, and the monomer dropping rate. It can be controlled by etc.

The adhesive layer or the adhesive forming the adhesive layer may contain a crosslinking agent. For example, when an acrylic polymer is used as the base polymer, the acrylic polymer can be crosslinked to further reduce the amount of low molecular weight substances in the adhesive layer. Moreover, the number average molecular weight of the acrylic polymer can be increased.

Examples of the crosslinking agent include polyisocyanate compounds, epoxy compounds, polyol compounds (such as polyphenol compounds), aziridine compounds, and melamine compounds. When a crosslinking agent is used, the amount used is preferably 6 parts by weight or less, more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the base polymer.

The adhesive forming the adhesive layer may contain a polymerization initiator. As the polymerization initiator, for example, an azo polymerization initiator, a peroxide polymerization initiator, a redox polymerization initiator, etc. are used depending on the polymerization method. Examples of the azo polymerization initiator include 2,2'-azobisisobutyronitrile, 2,2'-azobis-2-methylbutyronitrile, and dimethyl 2,2'-azobis(2-methylpropionic acid). , 4,4'-azobis-4-cyanovaleric acid and the like. Examples of the peroxide polymerization initiator include dibenzoyl peroxide and t-butyl permaleate.

Examples of the components that foam or expand upon heating include foaming agents and thermally expandable microspheres. Examples of the foaming agent include inorganic foaming agents and organic foaming agents. Examples of inorganic blowing agents include ammonium carbonate, ammonium hydrogen carbonate, sodium hydrogen carbonate, ammonium nitrite, sodium borohydride, and azides. Examples of organic blowing agents include salt fluorinated alkanes such as trichloromonofluoromethane and dichloromonofluoromethane; azo compounds such as azobisisobutyronitrile, azodicarbonamide, and barium azodicarboxylate; paratoluenesulfonyl Hydrazine compounds such as hydrazide, diphenylsulfone-3,3'-disulfonylhydrazide, 4,4'-oxybis(benzenesulfonylhydrazide), allylbis(sulfonylhydrazide); ρ-tolylenesulfonyl semicarbazide, 4,4'-oxybis Semicarbazide compounds such as (benzenesulfonyl semicarbazide); Triazole compounds such as 5-morpholyl-1,2,3,4-thiatriazole; N,N'-dinitrosopentamethylenetetramine, N,N'-dimethyl-N , N'-dinitrosoterephthalamide, and other N-nitroso compounds.

Examples of the thermally expandable microspheres include microspheres in which a substance that easily gasifies and expands when heated is enclosed in a shell. Examples of substances that easily gasify and expand upon heating include isobutane, propane, pentane, and the like. Thermally expandable microspheres can be produced by encapsulating a substance that easily gasifies and expands upon heating into a shell-forming substance by a coacervation method, an interfacial polymerization method, or the like. As the shell-forming substance, it is possible to use a substance that exhibits thermal fusibility or a substance that can burst due to the action of thermal expansion of the encapsulating substance. Such substances include, for example, vinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, polyvinylidene chloride, polysulfone, and the like.

When the adhesive force-reducing adhesive layer is a heat-foaming adhesive layer, the thickness of the adhesive layer is, for example, 5 to 100 μm.

As the radiation-curable adhesive, for example, a type of adhesive that is cured by irradiation with electron beams, ultraviolet rays, alpha rays, beta rays, gamma rays, or X-rays can be used; Adhesives (ultraviolet curable adhesives) can be particularly preferably used.

The radiation-curable adhesive may contain, for example, a base polymer such as the acrylic polymer and a radiation-polymerizable monomer component or oligomer component having a radiation-polymerizable functional group such as a carbon-carbon double bond. Examples include additive-type radiation-curable adhesives.

Examples of the acrylic polymer that can be included in the radiation-curable adhesive include those exemplified and explained as the acrylic polymer that can be included in the heat-foamable adhesive layer.

Examples of the radiation-polymerizable monomer components include trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, and dipentaerythritol monohydroxypenta(meth)acrylate. Examples include erythritol hexa(meth)acrylate and 1,4-butanediol di(meth)acrylate.

Examples of the radiation-polymerizable oligomer component include various oligomers such as urethane-based, polyether-based, polyester-based, polycarbonate-based, and polybutadiene-based oligomers, and those having a molecular weight of about 100 to 30,000 are suitable. The total content of radiation-polymerizable monomer components and oligomer components in the radiation-curable adhesive is determined within a range that allows the adhesive strength of the radiation-curable adhesive layer to be formed to be appropriately reduced by radiation irradiation. The amount is, for example, 5 to 500 parts by weight, preferably 40 to 150 parts by weight, based on 100 parts by weight of a base polymer such as a polymer.

Further, as the additive-type radiation-curable adhesive, for example, one disclosed in JP-A-60-196956 may be used.

The above-mentioned radiation-curable adhesive is an intrinsic radiation-curable adhesive containing a base polymer having a radiation-polymerizable functional group such as a carbon-carbon double bond in the polymer side chain, in the polymer main chain, or at the end of the polymer main chain. Also included are adhesives. When such an internal radiation-curable adhesive is used, it tends to be possible to suppress unintended changes in adhesive properties over time due to movement of low molecular weight components within the formed adhesive layer.

The base polymer contained in the above-mentioned internal radiation-curable adhesive is preferably an acrylic polymer. Examples of the acrylic polymer include those exemplified and explained as acrylic polymers that can be included in the heat-foamable adhesive layer. As a method for introducing a radiation-polymerizable carbon-carbon double bond into an acrylic polymer, for example, a raw material monomer containing a monomer component having a functional group (first functional group) is polymerized (copolymerized) to form an acrylic polymer. After obtaining the polymer, a compound having a functional group (second functional group) that can react with the first functional group to form a bond and a radiation-polymerizable carbon-carbon double bond, Examples include a method in which an acrylic polymer is subjected to a condensation reaction or an addition reaction while maintaining radiation polymerizability of carbon-carbon double bonds.

Combinations of the first functional group and the second functional group include, for example, a carboxy group and an epoxy group, an epoxy group and a carboxy group, a carboxyl group and an aziridyl group, an aziridyl group and a carboxy group, a hydroxy group and an isocyanate group, Examples include isocyanate groups and hydroxy groups. Among these, a combination of a hydroxy group and an isocyanate group, and a combination of an isocyanate group and a hydroxy group are preferred from the viewpoint of ease of tracking the reaction. Among these, it is technically difficult to produce a polymer having a highly reactive isocyanate group.On the other hand, from the viewpoint of ease of production and availability of an acrylic polymer having a hydroxy group, it is difficult to produce a polymer having a highly reactive isocyanate group. A combination in which the functional group is a hydroxy group and the second functional group is an isocyanate group is preferred.

Examples of compounds having a radioactively polymerizable carbon-carbon double bond and an isocyanate group include methacryloyl isocyanate, 2-acryloyloxyethyl isocyanate, 2-methacryloyloxyethyl isocyanate (MOI), m-isopropenyl-α,α-dimethylbenzyl Examples include isocyanates.

The radiation-curable adhesive preferably contains a photopolymerization initiator. Examples of the photopolymerization initiator include α-ketol compounds, acetophenone compounds, benzoin ether compounds, ketal compounds, aromatic sulfonyl chloride compounds, photoactive oxime compounds, benzophenone compounds, thioxanthone compounds, Examples include camphorquinone, halogenated ketones, acylphosphinoxides, acyl phosphonates, and the like.

Examples of the above α-ketol compounds include 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)ketone, α-hydroxy-α,α'-dimethylacetophenone, and 2-methyl-2-hydroxy Examples include propiophenone and 1-hydroxycyclohexylphenyl ketone.

Examples of the acetophenone compounds include methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, 2-methyl-1-[4-(methylthio)-phenyl]-2 -morpholinopropane-1, etc.

Examples of the benzoin ether compounds include benzoin ethyl ether, benzoin isopropyl ether, anisoin methyl ether, and the like. Examples of the above-mentioned ketal compounds include benzyl dimethyl ketal.

Examples of the aromatic sulfonyl chloride compounds include 2-naphthalenesulfonyl chloride. Examples of the photoactive oxime compounds include 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl) oxime.

Examples of the benzophenone compounds include benzophenone, benzoylbenzoic acid, and 3,3'-dimethyl-4-methoxybenzophenone.

Examples of the thioxanthone compounds include thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropyl Examples include thioxanthone.

The content of the photopolymerization initiator in the radiation-curable adhesive is, for example, 0.05 to 20 parts by weight based on 100 parts by weight of the base polymer.

When the adhesive force-reducing adhesive layer is a radiation-curable adhesive layer, the thickness of the adhesive layer is, for example, 2 to 50 μm.

In addition to the above-mentioned components, the reduced-adhesive adhesive layer or the adhesive forming the adhesive layer may contain known or commonly used adhesives such as tackifiers, anti-aging agents, and colorants (pigments, dyes, etc.). Additives used in the agent layer may be blended.

Examples of the coloring agent include compounds that are colored by radiation irradiation. When containing a compound that is colored by radiation irradiation, only the portion irradiated with radiation can be colored. The compound that is colored by radiation irradiation is a compound that is colorless or light-colored before radiation irradiation, but becomes colored by radiation irradiation, and includes, for example, leuco dye. The amount of the compound that is colored by radiation irradiation is not particularly limited and can be selected as appropriate.

(Adhesive layer)
The pressure-sensitive adhesive layer (for example, pressure-sensitive adhesive layer 13) that is paired with the pressure-reduced pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive sheet has little or no adhesive force depending on external effects during the use of the semiconductor process sheet. It is preferable to use an adhesive layer that does not reduce adhesive strength (adhesive force non-reduced type adhesive layer). The above-mentioned adhesive strength-reduced adhesive layer can be easily peeled off from the adherend by performing adhesive strength reduction treatment (particularly, in the case of a heat-foaming adhesive layer, by foaming it by heating). On the other hand, the non-adhesive strength adhesive layer does not cause adhesive strength reduction such as foaming due to heating. Therefore, according to the semiconductor process sheet of the present invention having such a configuration, the double-sided adhesive sheet can be easily peeled off from only one adhesive surface of the adherend by heating.

Examples of the above-mentioned adhesive layer that does not reduce adhesive strength include a pressure-sensitive adhesive layer, and a type that maintains adhesive strength to the extent that it can be used in the semiconductor package manufacturing process although its adhesive strength decreases due to radiation irradiation (the second type). ) is an adhesive layer formed from a radiation-curable adhesive.

As the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer as the adhesive layer, known or commonly used pressure-sensitive adhesives can be used, such as acrylic adhesives having an acrylic polymer as a base polymer, rubber Examples include silicone-based adhesives and silicone-based adhesives. When the pressure-sensitive adhesive layer contains an acrylic polymer, the acrylic polymer is preferably a polymer containing a structural unit derived from a (meth)acrylic acid ester as the largest structural unit in mass proportion. Examples of the acrylic polymer include those exemplified and explained as the acrylic polymer that can be included in the heat-expandable pressure-sensitive adhesive layer described above. The number of adhesives forming the above-mentioned adhesive layer may be only one type, or two or more types may be used.

The second type of radiation-curable adhesive includes, for example, a base polymer such as the acrylic polymer, and a radiation-polymerizable monomer component or oligomer component having a radiation-polymerizable functional group such as a carbon-carbon double bond. An example is an additive-type radiation-curable adhesive containing the following. Examples of the components constituting the additive-type radiation-curable adhesive include those exemplified and explained as components constituting the additive-type radiation-curable adhesive for the adhesive force-reduced adhesive layer. . The degree of adhesive strength reduction due to radiation irradiation in additive-type radiation-curable adhesives is determined by, for example, the content of radiation-polymerizable functional groups such as carbon-carbon double bonds, and the type and composition of photopolymerization initiators. Can be controlled by quantity. Note that, as the second type of radiation-curable adhesive, a radiation-curable adhesive that is cured in advance by radiation is usually used. In this way, the radiation-curable adhesive maintains a certain degree of adhesive strength even if it is pre-cured. Moreover, such curing may be performed on the entire surface of the adhesive layer, or may be performed only on an arbitrary part on the center side of the adhesive layer.

The second type of radiation-curable adhesive has an internal base polymer containing a radiation-polymerizable functional group such as a carbon-carbon double bond in the polymer side chain, in the polymer main chain, or at the end of the polymer main chain. Also included are radiation curable adhesives of the type. Examples of the components constituting the internal type radiation-curable adhesive include those exemplified and explained as components constituting the internal type radiation-curable adhesive for the adhesive force-reduced adhesive layer. . Regarding the degree of adhesive strength reduction due to radiation irradiation in endogenous radiation-curable adhesives, for example, the content of radiation-polymerizable functional groups such as carbon-carbon double bonds, and the type and composition of photopolymerization initiators Can be controlled by quantity.

The thickness of the adhesive layer is, for example, 1 to 50 μm.

In addition to the above-mentioned components, the above-mentioned pressure-sensitive adhesive layer or the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer contains a tackifier, an anti-aging agent, a coloring agent (pigment, dye, etc.) and other known or commonly used adhesives for the pressure-sensitive adhesive layer. Additives may be included.

Examples of the coloring agent include compounds that are colored by radiation irradiation. When containing a compound that colors when irradiated with radiation, only the portion that is irradiated with radiation can be colored. The compound that is colored by radiation irradiation is a compound that is colorless or light-colored before radiation irradiation, but becomes colored by radiation irradiation, and includes, for example, leuco dye. The amount of the compound that is colored by radiation irradiation is not particularly limited and can be selected as appropriate.

The double-sided pressure-sensitive adhesive sheet of the semiconductor process sheet of the present invention may have other layers in its laminated structure in addition to the above-described base material, pressure-reducing pressure-sensitive adhesive layer, and pressure-sensitive adhesive layer. Examples of the other layers include, for example, a thin adhesive layer provided on the adhesive layer to provide an adhesive surface when the adhesive force-reducing adhesive layer is a heat-foaming adhesive layer, and a thin adhesive layer that provides an adhesive surface for reducing adhesive force. Examples include a rubber-like organic elastic layer provided between the adhesive layer and the base material when the adhesive layer is a heat-foaming adhesive layer.

When the thin adhesive layer covering the surface of the heat-foamable adhesive layer is adhered to an adherend, the heat-foamable adhesive layer expands due to heating and deforms its surface irregularities. Along with this, the thin adhesive layer is also deformed, reducing its total adhesion area to the adherend and decreasing its adhesive force to the adherend. It becomes possible to utilize the desired adhesive force in a thin adhesive layer while utilizing the adhesive force reduction function of the heat-foamable adhesive. The thickness of the thin adhesive layer is, for example, 2 to 30 μm.

Furthermore, by providing a rubber-like organic elastic layer between the base material and the heat-foamable adhesive layer, the heat-foamable adhesive layer can be expanded preferentially and with high uniformity in the thickness direction by heating. Become. Such a rubbery organic elastic layer is formed of, for example, natural rubber or synthetic rubber having a Shore D hardness of 50 or less based on ASTM D-2240, or a synthetic resin having rubber elasticity. Synthetic rubbers and the above synthetic resins for the rubbery organic elastic layer include, for example, synthetic rubbers such as nitrile rubber, diene rubber, and acrylic rubber; thermoplastic elastomers such as polyolefin resins and polyester resins; ethylene-acetic acid Examples include synthetic resins having rubber elasticity such as vinyl copolymers, polyurethane, polybutadiene, and soft polyvinyl chloride. The thickness of the rubber-like organic elastic layer is, for example, 1 to 500 μm.

(Thermosetting resin layer)
As described above, the thermosetting resin layer is releasably adhered to at least one adhesive surface of the double-sided adhesive sheet. The thickness of the thermosetting resin layer is, for example, 1 to 300 μm.

The thermosetting resin layer is a chip fixing resin layer for fixing a semiconductor chip that is an element of a semiconductor package to be manufactured. The thermosetting resin layer may be a chip electrode embedding resin layer (chip electrode embedding adhesive layer) for embedding a chip electrode of a semiconductor chip. That is, the semiconductor process sheet of the present invention may be designed so that a semiconductor chip is mounted either face-up or face-down on the thermosetting resin layer.

The thickness of the thermosetting resin layer when it is a chip electrode embedding resin layer is preferably 1 to 300 μm, more preferably 5 to 250 μm, and still more preferably 10 to 200 μm. Further, the ratio of the thickness of the thermosetting resin layer to the height of the chip electrode to be embedded is preferably 0.1 to 10, more preferably 0.2 to 9.

The thermosetting resin layer contains, for example, a thermosetting resin and a thermoplastic resin as resin components. Alternatively, the thermosetting resin layer may contain, as a resin component, a thermoplastic resin having a thermosetting functional group that can react with a curing agent to form a bond. The semiconductor process sheet of the present invention is subjected to a semiconductor package manufacturing process with the thermosetting resin layer in an uncured state.

When the thermosetting resin layer contains a thermosetting resin together with a thermoplastic resin, examples of the thermosetting resin include epoxy resin, phenol resin, amino resin, unsaturated polyester resin, polyurethane resin, silicone resin, thermosetting resin, etc. Examples include curable polyimide resin. The above thermosetting resins may be used alone or in combination of two or more. Epoxy resins are preferable from the viewpoint that they tend to contain less ionic impurities and the like that can cause corrosion of semiconductor chips. Further, as a curing agent for making the epoxy resin exhibit thermosetting properties, a phenol resin is preferable.

Examples of the above epoxy resin include bisphenol A type, bisphenol F type, bisphenol S type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol AF type, biphenyl type, naphthalene type, fluorene type, phenol novolak type, ortho Examples include cresol novolak type, trishydroxyphenylmethane type, tetraphenylolethane type, hydantoin type, trisglycidyl isocyanurate type, and glycidylamine type epoxy resins. The above epoxy resins may be used alone or in combination of two or more.

Examples of the phenolic resin that can act as a curing agent for epoxy resins include novolac-type phenolic resins, resol-type phenolic resins, and polyoxystyrenes such as polyparaoxystyrene. Examples of the novolak type phenolic resin include phenol novolak resin, phenol aralkyl resin, cresol novolak resin, t-butylphenol novolak resin, and nonylphenol novolak resin. The above phenol resins may be used alone or in combination of two or more.

In the thermosetting resin layer, from the viewpoint of sufficiently advancing the curing reaction between the epoxy resin and the phenol resin, the phenol resin preferably has a hydroxyl group in the phenol resin per equivalent of the epoxy group in the epoxy resin component. is contained in an amount of 0.5 to 2.0 equivalents, more preferably 0.7 to 1.5 equivalents.

When the thermosetting resin layer contains a thermosetting resin, the content ratio of the thermosetting resin is determined based on the total mass of the thermosetting resin layer from the viewpoint of appropriately curing the thermosetting resin layer. The amount is preferably 5 to 60% by weight, more preferably 10 to 50% by weight, even more preferably 15 to 45% by weight, particularly preferably 20 to 40% by weight. When the content ratio of the thermosetting resin is within the above range, the thermosetting resin layer can be thermally cured to cause moderate warping in the opposite direction to the warping that occurs in conventional semiconductor packages. Accordingly, warping can be further suppressed.

The thermoplastic resin in the thermosetting resin layer has a binder function, for example. When the thermosetting resin layer contains a thermosetting resin together with a thermoplastic resin, examples of the thermoplastic resin include acrylic resin, natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, and ethylene-vinyl acetate copolymer. , ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, polybutadiene resin, polycarbonate resin, thermoplastic polyimide resin, polyamide resin such as 6-nylon and 6,6-nylon, phenoxy resin, PET and PBT, etc. Examples include saturated polyester resin, polyamideimide resin, and fluororesin. The above thermoplastic resins may be used alone or in combination of two or more. As the thermoplastic resin, acrylic resin is preferable from the viewpoint of having less ionic impurities and high heat resistance.

It is preferable that the acrylic resin contains a structural unit derived from a hydrocarbon group-containing (meth)acrylic ester as the largest structural unit in mass proportion. The hydrocarbon group-containing (meth)acrylic ester is exemplified and explained as, for example, a hydrocarbon group-containing (meth)acrylic ester that forms an acrylic polymer that can be included in the above-mentioned adhesive force-reducing adhesive layer. There are many things that can be mentioned.

The acrylic resin may contain structural units derived from other monomer components copolymerizable with the hydrocarbon group-containing (meth)acrylic ester. Examples of the other monomer components include carboxy group-containing monomers, acid anhydride monomers, hydroxy group-containing monomers, glycidyl group-containing monomers, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, and functional group-containing monomers such as acrylamide and acrylonitrile. Examples include monomers and various polyfunctional monomers, and specifically, those exemplified and explained as other monomer components constituting the acrylic polymer that can be included in the above-mentioned adhesive force-reducing adhesive layer. Can be mentioned.

When the thermosetting resin layer contains a thermoplastic resin having a thermosetting functional group, for example, an acrylic resin containing a thermosetting functional group can be used as the thermoplastic resin. The acrylic resin in this thermosetting functional group-containing acrylic resin preferably contains a structural unit derived from a hydrocarbon group-containing (meth)acrylic acid ester as the largest structural unit in mass proportion. The hydrocarbon group-containing (meth)acrylic ester is exemplified and explained as, for example, a hydrocarbon group-containing (meth)acrylic ester that forms an acrylic polymer that can be included in the above-mentioned adhesive force-reducing adhesive layer. There are many things that can be mentioned.

Examples of the thermosetting functional group in the thermosetting functional group-containing acrylic resin include a glycidyl group, a carboxy group, a hydroxy group, and an isocyanate group. Among these, a glycidyl group and a carboxy group are preferred. That is, particularly preferred as the thermosetting functional group-containing acrylic resin are glycidyl group-containing acrylic resins and carboxyl group-containing acrylic resins. Further, it is preferable that a curing agent is included together with the thermosetting functional group-containing acrylic resin, and examples of the curing agent include cross-linking that can be included in the radiation-curable adhesive for forming the above-mentioned adhesive force-reduced adhesive layer. Agents include those exemplified and described. When the thermosetting functional group in the thermosetting functional group-containing acrylic resin is a glycidyl group, it is preferable to use a polyphenol compound as the curing agent, and for example, the various phenolic resins mentioned above can be used.

The adhesive for forming the thermosetting resin layer preferably contains a thermosetting catalyst. When the thermosetting catalyst is used, the curing reaction of the resin component can be sufficiently progressed and the curing reaction rate can be increased when curing the thermosetting resin layer. The above thermosetting catalysts may be used alone or in combination of two or more.

Examples of the thermosetting catalyst include imidazole compounds, triphenylphosphine compounds, amine compounds, and trihalogenborane compounds.

Examples of the imidazole compounds include 2-methylimidazole, 2-undecylimidazole, 2-heptadecyl imidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl -4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenyl Imidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-undecylimidazolyl-( 1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6 -[2'-Methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, etc. can be mentioned.

Examples of the triphenylphosphine compounds include triphenylphosphine, tributylphosphine, tri(p-methylphenylphosphine, tri(nonylphenyl)phosphine, diphenyltolylphosphine, tetraphenylphosphonium bromide, methyltriphenyl Examples include phosphonium, methyltriphenylphosphonium chloride, methoxymethyltriphenylphosphonium, and benzyltriphenylphosphonium chloride.

The above-mentioned triphenylphosphine compounds include compounds having both a triphenylphosphine structure and a triphenylborane structure. Examples of such compounds include tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium tetra-p-triborate, benzyltriphenylphosphonium tetraphenylborate, triphenylphosphine triphenylborane, and the like.

Examples of the above amine compounds include monoethanolamine trifluoroborate and dicyandiamide. Examples of the trihalogen borane compounds include trichloroborane.

The thermosetting resin layer may contain a filler. By blending the filler into the thermosetting resin layer, the physical properties of the thermosetting resin layer, such as its elastic modulus, yield point strength, and elongation at break, can be adjusted. Examples of fillers include inorganic fillers and organic fillers.

Examples of constituent materials of the inorganic filler include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate whiskers, and nitride. Examples include boron, crystalline silica, and amorphous silica. In addition, examples of constituent materials of the inorganic filler include simple metals such as aluminum, gold, silver, copper, and nickel, alloys, amorphous carbon black, and graphite. Examples of constituent materials of the organic filler include polymethyl methacrylate (PMMA), polyimide, polyamideimide, polyetheretherketone, polyetherimide, and polyesterimide. The filler may have various shapes such as spherical, acicular, and flaky. The above fillers may be used alone or in combination of two or more.

The average particle size of the filler is preferably 0.002 to 10 μm, more preferably 0.005 to 1 μm. When the average particle size is 10 μm or less, the effect of the filler added to impart each of the above properties can be made sufficient, and heat resistance can be ensured. The average particle size of the filler can be determined using, for example, a photometric particle size distribution analyzer (eg, trade name "LA-910", manufactured by Horiba, Ltd.).

When the thermosetting resin layer contains a filler, the content of the filler is preferably 10% by mass or more, more preferably 15% by mass or more, even more preferably It is 20% by mass or more. The content ratio is, for example, 60% by mass or less, preferably 55% by mass or less, and more preferably 50% by mass or less.

The thermosetting resin layer may contain a colorant. The coloring agent may be a pigment or a dye. Examples of the coloring agent include a black coloring agent, a cyan coloring agent, a magenta coloring agent, and a yellow coloring agent. The above coloring agents may be used alone or in combination of two or more.

Examples of black colorants include copper oxide, manganese dioxide, azo pigments such as azomethine azo black, aniline black, perylene black, titanium black, cyanine black, activated carbon, ferrite, magnetite, chromium oxide, iron oxide, and disulfide. Examples include molybdenum, complex oxide black pigments, anthraquinone organic black dyes, and azo organic black dyes. As the black colorant, C. I. Solvent Black 3, Solvent Black 7, Solvent Black 22, Solvent Black 27, Solvent Black 29, Solvent Black 34, Solvent Black 43, and Solvent Black 70 may also be mentioned. As the black colorant, C. I. Direct Black 17, Direct Black 19, Direct Black 22, Direct Black 32, Direct Black 38, Direct Black 51, and Direct Black 71 are also included. As the black colorant, C. I. Also included are Acid Black 1, Acid Black 2, Acid Black 24, Acid Black 26, Acid Black 31, Acid Black 48, Acid Black 52, Acid Black 107, Acid Black 109, Acid Black 110, Acid Black 119, and Acid Black 154. As the black colorant, C. I. Disperse Black 1, Disperse Black 3, Disperse Black 10, and Disperse Black 24 are also included. As the black colorant, C. I. Pigment Black 1 and Pigment Black 7 may also be mentioned.

The content ratio of the colorant in the thermosetting resin layer may be 0% by weight based on the total mass of the thermosetting resin layer, but when used, it is preferably 0.5% by weight or more, for example. is 1% by weight or more, more preferably 2% by weight or more. The content ratio is, for example, 10% by weight or less, preferably 8% by weight or less, and more preferably 5% by weight or less.

The thermosetting resin layer may contain other components as necessary. Examples of the other components include flame retardants, silane coupling agents, and ion trapping agents. The above-mentioned other components may be used alone or in combination of two or more.

Examples of the flame retardant include antimony trioxide, antimony pentoxide, and brominated epoxy resin.

Examples of the silane coupling agent include β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropylmethyldiethoxysilane.

Examples of the ion trapping agent include hydrotalcites, bismuth hydroxide, hydrated antimony oxide (for example, "IXE-300" manufactured by Toagosei Co., Ltd.), and zirconium phosphate with a specific structure (for example, "IXE-300" manufactured by Toagosei Co., Ltd.). Examples include "IXE-100"), magnesium silicate (for example, "Kyoward 600" manufactured by Kyowa Chemical Industry Co., Ltd.), and aluminum silicate (for example, "Kyoward 700" manufactured by Kyowa Chemical Industry Co., Ltd.).

Compounds that can form complexes with metal ions can also be used as ion trapping agents. Examples of such compounds include triazole compounds, tetrazole compounds, bipyridyl compounds, and the like. Among these, triazole compounds are preferred from the viewpoint of stability of complexes formed with metal ions.

Examples of the triazole compounds include 1,2,3-benzotriazole, 1-{N,N-bis(2-ethylhexyl)aminomethyl}benzotriazole, carboxybenzotriazole, 2-(2-hydroxy-5- methylphenyl)benzotriazole, 2-(2-hydroxy-3,5-di-t-butylphenyl)-5-chlorobenzotriazole, 2-(2-hydroxy-3-t-butyl-5-methylphenyl)- 5-chlorobenzotriazole, 2-(2-hydroxy-3,5-di-t-amylphenyl)benzotriazole, 2-(2-hydroxy-5-t-octylphenyl)benzotriazole, 6-(2-benzo triazolyl)-4-t-octyl-6'-t-butyl-4'-methyl-2,2'-methylenebisphenol, 1-(2,3-dihydroxypropyl)benzotriazole, 1-(1,2 -dicarboxydiethyl)benzotriazole, 1-(2-ethylhexylaminomethyl)benzotriazole, 2,4-di-t-pentyl-6-{(H-benzotriazol-1-yl)methyl}phenol, 2-( 2-hydroxy-5-t-butylphenyl)-2H-benzotriazole, octyl-3-[3-t-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazol-2-yl)phenyl] Propionate, 2-ethylhexyl-3-[3-t-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazol-2-yl)phenyl]propionate, 2-(2H-benzotriazol-2-yl) )-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol, 2-(2H-benzotriazol-2-yl)-4-t-butylphenol , 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2-(2-hydroxy-5-t-octylphenyl)-benzotriazole, 2-(3-t-butyl-2-hydroxy-5-methyl phenyl)-5-chlorobenzotriazole, 2-(2-hydroxy-3,5-di-t-amylphenyl)benzotriazole, 2-(2-hydroxy-3,5-di-t-butylphenyl)-5 -Chloro-benzotriazole, 2-[2-hydroxy-3,5-di(1,1-dimethylbenzyl)phenyl]-2H-benzotriazole, 2,2'-methylenebis[6-(2H-benzotriazole-2 -yl)-4-(1,1,3,3-tetramethylbutyl)phenol], 2-[2-hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl]-2H-benzotriazole, Examples include methyl-3-[3-(2H-benzotriazol-2-yl)-5-t-butyl-4-hydroxyphenyl]propionate.

Further, specific hydroxyl group-containing compounds such as quinol compounds, hydroxyanthraquinone compounds, and polyphenol compounds can also be used as ion trapping agents. Specific examples of such hydroxyl group-containing compounds include 1,2-benzenediol, alizarin, anthralphine, tannin, gallic acid, methyl gallate, and pyrogallol.

The semiconductor process sheet of the present invention may be produced by forming the above-mentioned thermosetting resin layer on one adhesive surface of a double-sided adhesive sheet, or by forming the thermosetting resin layer formed on a separator. It may also be produced by bonding it to one adhesive side of a separately produced double-sided adhesive sheet. The double-sided pressure-sensitive adhesive sheet may be produced by forming the reduced-adhesion type adhesive layer and the pressure-sensitive adhesive layer on a base material, or by forming the reduced-adhesion type adhesive layer and the pressure-sensitive adhesive layer on a separator. It may be produced by bonding each adhesive layer formed on a separate separator to a base material. Each layer can be formed, for example, by applying a pressure-sensitive adhesive composition prepared for each layer and removing the solvent.

[Semiconductor package manufacturing method]
A semiconductor package can be manufactured using the semiconductor process sheet of the present invention. 2 to 7 represent an embodiment of a method for manufacturing a semiconductor package using a semiconductor process sheet X, which is an embodiment of the semiconductor process sheet of the present invention.

The method for manufacturing a semiconductor package shown in FIGS. 2 to 7 is a method for manufacturing a semiconductor package using a semiconductor process sheet step, and singulation step in this order.

First, in the chip mounting process, as shown in FIGS. 2(a) and 2(b), the thermosetting resin layer 20 of the semiconductor process sheet X whose adhesive surface 10a side is bonded to the support S is A plurality of semiconductor chips C are mounted. The support S is made of metal, glass, or transparent resin, for example. The semiconductor chip C has a chip body and a chip electrode E extending from the chip body. In this embodiment, the semiconductor chip C is mounted face-up with the surface not having the chip electrode E facing the thermosetting resin layer 20. As shown in FIG. 4(a), after mounting the semiconductor chip C on the thermosetting resin layer 20, the thermosetting resin layer is heated to a predetermined degree of hardening (that is, the first peeling force is The thermosetting resin 20 may be cured by heating so that the degree of curing is 5N or more and the first peeling force is larger than the second peeling force). The above-mentioned curing may be either semi-curing (curing within the range of a substantially uncured state) or curing (curing to a substantially cured state). However, as long as the first peel force is 5 N or more and the first peel force is larger than the second peel force, the thermosetting resin layer 20 does not need to be cured.

Next, in the sealing step, as shown in FIG. 3(a), a sealing material 30' is supplied so as to embed the plurality of semiconductor chips C on the semiconductor process sheet As shown in b), the encapsulant 30' is cured to form the encapsulant portion 30. When the sealing material 30' is cured, the thermosetting resin layer 20 is also cured if it is not completely cured. Thereby, a package P (chip embedding sealing material part) as the sealing material part 30 in which the semiconductor chip C is embedded is obtained. The sealing material 30' is a composition containing, for example, a curing agent such as an epoxy resin or a phenol resin, an inorganic filler, a curing accelerator, and a black colorant. It may be supplied in any of the following forms: As the constituent material of such a sealing material 30', for example, those illustrated and explained as the constituent material of the thermosetting resin layer 20 of the semiconductor process sheet X can be used. In this step, the heating temperature for forming the sealing material portion 30 is, for example, 150 to 185° C., and the heating time is, for example, 60 seconds to several hours.

In this manufacturing method, after the chip mounting step described above with reference to FIG. 2, and before supplying the sealing material 30' onto the semiconductor process sheet X, as shown in FIG. The resin layer 20 may be cured to a predetermined degree of hardening, or may be completely cured (curing step). In this case, in the sealing process, first, as shown in FIG. The sealant 30' is cured on the cured thermosetting resin layer 20 to a predetermined degree of cure (particularly the degree of cure in the cured state), and the sealant part 30 is cured as shown in FIG. 3(b). It is formed. Note that at this time, the thermosetting resin layer 20, which has already been cured to a predetermined degree of curing, may be further cured. According to such a configuration, the sealing process is performed in a state where the holding power of the semiconductor chip C by the semiconductor process sheet It will be done. Therefore, this configuration can further suppress the movement (positional shift) of the semiconductor chip C caused by shrinkage of the sealing material 30' during curing and the adhesive force of the double-sided pressure-sensitive adhesive sheet during the sealing process. Such suppression of semiconductor chip positional shift is also preferable, for example, when accurately forming a wiring structure including wiring for each semiconductor chip C in a later wiring forming process.

Next, in the above-described detaching step, as shown in FIG. 5(a), the state in which the package P is supported by the support body S is released. In this step, for example, the semiconductor process sheet X and the support S are separated, and then the double-sided adhesive sheet 10 or its adhesive surface 10b is separated from the package P (chip embedding sealing material part). Alternatively, after the package P is separated from the double-sided adhesive sheet 10 on the support S, the double-sided adhesive sheet 10 is peeled off from the support S.

When the adhesive layer 12 (adhesive force reduction type adhesive layer) of the double-sided adhesive sheet 10 in the semiconductor process sheet By lowering the adhesive force of 10a, it is possible to separate the support S and the double-sided adhesive sheet 10. The heating temperature for this purpose is, for example, 170 to 200°C.

When the adhesive layer 12 (adhesive force reduction type adhesive layer) of the double-sided adhesive sheet 10 in the semiconductor process sheet Irradiation reduces the adhesive strength of the adhesive layer 12 or the adhesive surface 10a, allowing the support S and the double-sided adhesive sheet 10 to be separated from each other. When the radiation irradiation for this purpose is ultraviolet irradiation, the irradiation amount is, for example, 50 to 500 mJ/cm ² .

In the above-mentioned face-up chip mounting process, if the chip electrode E of the semiconductor chip C is embedded in the encapsulant part 30, each semiconductor chip in the encapsulant part 30 is removed after the detaching process. A grinding process is performed on the sealing material portion 30 to expose the chip electrode E of C to the outside.

Next, in the wiring forming step, as shown in FIG. 5B, a wiring structure section 40 including wiring for each semiconductor chip C is formed on the sealing material section 30 and the package P. The wiring for each semiconductor chip C includes external electrodes 41 such as bump electrodes in each semiconductor package that will be manufactured for each semiconductor chip C by this manufacturing method.

Next, in the above-mentioned thinning process, after the back grinding tape Y is pasted on the wiring structure part 40 side as shown in FIG. A grinding process is performed on the package P to make the package P thinner. The backgrind tape Y has an adhesive layer Ya thick enough to embed the external electrode 41 of the wiring structure section 40. In this step, for example, the sealing material portion 30 is ground so that the so-called back surface of the semiconductor chip C is exposed, or the semiconductor chip C is thinned together with this.

Next, as shown in FIG. 7A, a dicing tape-integrated back protection film Z is attached to the package P held by the back grind tape Y. The dicing tape-integrated back protection film Z includes a dicing tape 50 having an adhesive layer and a curable film 60 for protecting the back surface of the semiconductor chip on the adhesive layer. The film 60 side of the body shape back protection film Z is pasted together. The film 60 for protecting the back surface of the semiconductor chip is an adhesive film containing a colorant such as a black colorant. As the coloring agent for the film 60, for example, those illustrated and explained as the coloring agent for the thermosetting resin layer 20 can be used. Further, the film 60 may be a thermosetting adhesive film, and can have sufficient adhesion to the adherend by being bonded to the adherend under a temperature condition of, for example, about 70°C. It may also be a non-curing type adhesive film that can be developed.

Next, the back grind tape Y is removed. If the film 60 is a thermosetting adhesive film, after the backgrind tape Y is removed, the film 60 is heat-cured as shown in FIG. 7(b).

Next, in the singulation step, as shown in FIG. 7(c), the encapsulant portion 30 and the wiring structure portion 40 are divided into individual semiconductor chips C by, for example, blade dicing (in FIG. 7(c), (Divide points are schematically shown with thick lines). Each semiconductor package thus separated into pieces is then picked up from the dicing tape 50.

Note that if the package P is not thinned by grinding as shown in FIG. 6(b), the backgrind tape Y in the package P held by the backgrind tape Y shown in FIG. 6(a) is not used. A dicing tape may be bonded to the surface of the sealing material section 30 instead. Then, each semiconductor chip C can be divided by the subsequent singulation process shown in FIG. 7(c). If the package P is not thinned, there is no need to go through a thinning process, so costs can be reduced. In this case, since the thermosetting resin layer 20 remains on the semiconductor chip C obtained by the singulation process, the thermosetting resin layer 20 is an adhesive film containing a coloring agent such as a black coloring agent. It is important to Note that when thinning the package P shown in FIG. 6(b), the thermosetting resin layer 20 is removed by grinding and does not remain on the semiconductor chip C, so the thermosetting resin layer 20 contains a colorant. There's no need.

As described above, a semiconductor package can be manufactured using the semiconductor process sheet X. Such a semiconductor package manufacturing method is suitable for efficiently manufacturing semiconductor packages. The reason is as follows.

When manufacturing a semiconductor package using a conventional semiconductor process sheet made of a double-sided adhesive sheet without the thermosetting resin layer 20, in the chip mounting process, both sides are bonded to the support S on one side. A plurality of semiconductor chips C are mounted on the other side of the adhesive sheet. At this time, face-up mounting is performed in which the side of the semiconductor chip C opposite to the chip electrode E is bonded to a double-sided adhesive sheet. Next, a sealing material portion for embedding the plurality of semiconductor chips C is formed on the double-sided adhesive sheet. Next, the double-sided adhesive sheet is peeled off from the encapsulant part (conventional chip embedding encapsulant part) in which the plurality of semiconductor chips C are embedded (detach step). In the conventional chip embedding sealing material part, the so-called back surface of each semiconductor chip C is exposed on the side from which the double-sided adhesive sheet is peeled off. Next, a resin sheet is bonded to the surface of such a sealing material section from which the double-sided pressure-sensitive adhesive sheet has been peeled off. As mentioned above, the back surface of each semiconductor chip C is exposed on the side of the encapsulant part from which the double-sided adhesive sheet has been peeled off, and the symmetry of the encapsulant part in the thickness direction is low. The sealing material portion inevitably warps. In such a warped state, subsequent processes cannot proceed appropriately. Therefore, in a semiconductor package manufacturing method that uses a conventional semiconductor process sheet made of a double-sided adhesive sheet, after the detaching process, the resin sheet is attached to the side from which the double-sided adhesive sheet was peeled off at the encapsulant part. Therefore, it is necessary to perform so-called warpage control on the conventional chip embedding sealing material.

On the other hand, in manufacturing a semiconductor package using the semiconductor process sheet of the present invention, the workpiece of the package P (chip embedding sealing material part 30) that has undergone the detaching process described above with reference to FIG. No special process for page control is required. This is because, in this manufacturing method, the semiconductor process sheet X with the thermosetting resin layer 20 on the double-sided adhesive sheet 10 is used. Specifically, a plurality of semiconductor chips C are mounted on the thermosetting resin layer 20 of the semiconductor process sheet X in the chip mounting process described above with reference to FIG. The encapsulant part 30 is formed from the encapsulant 30' provided to embed the semiconductor chip C and the thermosetting resin layer 20 or the cured thermosetting resin layer 20. This is because the chip-embedding encapsulant part 30 (package P) has higher symmetry in the thickness direction than the conventional chip-embedding encapsulant part described above, and is suitable for suppressing warpage. This manufacturing method, which does not require a process for warpage control of the chip-embedding sealing material part 30 or the package P, is preferable for efficiently manufacturing semiconductor packages.

Further, in the semiconductor process sheet of the present invention, the first peeling force of the thermosetting resin 20 to silicon such as the semiconductor chip C is 5N or more in an uncured state or a cured state at at least one point, and The second peel force of the curable resin 20 to the double-sided adhesive sheet 10 is designed to be greater than the second peel force. This allows the use of a conventional semiconductor process sheet made of a double-sided adhesive sheet that does not include the thermosetting resin layer 20, or a semiconductor process sheet that includes a thermosetting resin layer but whose first peeling force is smaller than the second peeling force. In the case where a semiconductor package is manufactured using the thermosetting resin layer 20 forming an adhesive surface with the chip body, the semiconductor chip C can be more firmly fixed (temporarily fixed), so that the sealing process and subsequent Movement (positional shift) of the semiconductor chip C can be prevented or suppressed. Furthermore, as shown in FIG. 2(b), this effect can be applied not only to the face-up chip mounting process in which the back surface of the semiconductor chip C is on the thermosetting resin layer 20 side, but also to the front surface of the semiconductor chip C. Even in a face-down chip mounting process in which the thermosetting resin layer 20 side is face-down, the chip electrode E is embedded and the chip body can form an adhesive surface with the thermosetting resin layer 20. The same effect as the mounting process can be obtained.

In the chip mounting process of this embodiment, as described above, preferably, the semiconductor chip C is bonded to the thermosetting resin layer 20 on the side of the chip body opposite to the chip electrode E. The semiconductor chip C is mounted on the resin layer 20. In this case, the present semiconductor package manufacturing method further includes a grinding step of grinding the sealing material part 30 to expose the chip electrode E of the semiconductor chip C after the detaching step described above with reference to FIG. 5(a), and In the wiring forming step described above with reference to FIG. 5(b), the wiring structure section 40 including the wiring electrically connected to the chip electrode E exposed on the surface of the sealing material section 30 is formed. . According to such a configuration, the wiring structure section 40 can be appropriately formed.

In the chip mounting step in the semiconductor package manufacturing method of the present invention, instead of face-up mounting, the chip electrode E of the semiconductor chip C enters the thermosetting resin layer 20 of the semiconductor process sheet Each semiconductor chip C may be mounted on the thermosetting resin layer 20 so as to reach the adhesive surface 10b. In this case, in the subsequent wiring formation step, a wiring structure section 40 including wiring electrically connected to the chip electrode E already exposed on the surface of the sealing material section 30 is formed. According to these configurations, the wiring structure part 40 can be appropriately formed without performing the grinding process of the sealing material part 30 which is required before the wiring formation process when going through the face-up chip mounting process.

The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited to these Examples in any way. In addition, the composition of each component constituting the thermosetting resin layer in Examples and Comparative Examples is shown in the table. However, in the table, the unit of each numerical value representing the composition of a layer is relative "parts by mass" within the layer.

Example 1
(Thermosetting resin layer)
Acrylic resin (trade name "AC-017", manufactured by Negami Kogyo Co., Ltd.) 100 parts by mass (blended amount as acrylic resin) and epoxy resin E ₁ (trade name "EPICLON HP-4700", manufactured by DIC Corporation) 206 parts by mass, 47 parts by mass of epoxy resin E ₂ (trade name "YSLV-80XY", manufactured by Nippon Steel Chemical & Materials Co., Ltd.), and 145 parts by mass of phenol resin (trade name "MEH7851-SS", manufactured by Meiwa Kasei Co., Ltd.) 1 part, 434 parts by mass of silica filler (trade name "SO-25R", average particle size: 0.5 μm, manufactured by Admatex Co., Ltd.), and a thermosetting catalyst (trade name "TPP-MK", Hokuko Chemical Industry Co., Ltd.) 2 parts by weight of methyl ethyl ketone were added and mixed to obtain a resin composition with a solid content concentration of 28% by weight.

Next, the resin composition was applied using an applicator onto the silicone release-treated surface of a PET separator (thickness: 50 μm) having a silicone release-treated surface to form a resin composition layer. Next, this composition layer was heated at 130° C. for 2 minutes to remove the solvent, thereby producing a 40 μm thick thermosetting resin layer of Example 1 on the PET separator.

(Preparation of semiconductor process sheet)
Heating expansion of double-sided adhesive sheet (trade name: "Riva Alpha No. 3195V", manufactured by Nitto Denko Corporation, three-layer composition of [heat-foaming adhesive layer / plastic base material / non-reduced adhesive layer]) The thermosetting resin layer of Example 1 was bonded to the mold adhesive layer. A hand roller was used for bonding. In the manner described above, the semiconductor process sheet of Example 1 was produced.

Examples 2-3
Semiconductor process sheets of Examples 2 and 3 were produced in the same manner as in Example 1, except that the blending amounts of various raw materials used for producing the thermosetting resin layer were changed as shown in Table 1.

Example 4
The use of the semiconductor process sheet of Example 3 is the same as in Example 3, but the method of use is different. Specifically, after placing a semiconductor chip on a semiconductor process sheet, the thermosetting resin layer is cured to a cured state (curing degree of 90% or more), and then, using a sealing material, Used in a sealed manner. Note that the conditions for curing the thermosetting resin layer to a cured state (curing degree of 90% or more) are heating conditions at 130° C. for 120 minutes, as shown in the evaluation method below.

Comparative example 1
A semiconductor process sheet of Comparative Example 1 was produced in the same manner as in Example 1 except that the thermosetting resin layer was not provided.

Comparative example 2
A semiconductor process sheet of Comparative Example 2 was produced in the same manner as in Example 1, except that the blending amounts of various raw materials used for producing the thermosetting resin layer were changed as shown in Table 1.

<Evaluation>
The semiconductor process sheets obtained in Examples and Comparative Examples were evaluated as follows. The results are shown in the table. Note that regarding the semiconductor process sheet of Comparative Example 1 that does not contain a thermosetting resin, evaluation was not performed on the items indicated with "-" in the table. In addition, in the following evaluation, a predetermined degree of curing means that the curing time is adjusted (adjusted in the range of 10 seconds to 2 hours) to bring the peeling force and shear adhesive strength of the thermosetting resin layer to a predetermined value. This is the degree of hardening. Examples 1 to 3 were cured to a substantially uncured state (semi-cured), and Example 4 was cured to a substantially cured state. For Comparative Examples 1 and 2, no curing was performed. The curing conditions of Example 4 were: oven temperature: 130° C., and heating time: 2 hours.

(1) Peeling force of thermosetting resin layer against silicone (first peeling force)
A test piece with a size of 20 mm width x 100 mm length was cut out from the thermosetting resin layer obtained in Examples and Comparative Examples. Next, the test piece was bonded to the mirror surface side of a silicon plate (unground bare wafer sold by Tokyo Kako Co., Ltd.) with the surface provided by the thermosetting resin layer. Further, the test piece was bonded to a support using the adhesive surface provided by the double-sided adhesive sheet surface. The bonding was carried out by pressing a 2 kg hand roller back and forth once. Next, the above laminate was placed in an oven at 130° C., and the thermosetting resin layer was cured by adjusting the time (adjusted within the range of 10 seconds to 2 hours) to achieve a predetermined degree of curing. . Then, using a tensile testing machine (trade name "Autograph AG-X", manufactured by Shimadzu Corporation), the test piece was subjected to a peel test at 23°C, a peel angle of 180°, and a tensile speed of 300 mm/min. The peeling force (first peeling force) of the thermosetting resin layer against the silicon plate in the semiconductor process sheets of Examples and Comparative Examples was measured. In Example 4, interfacial peeling occurred between the test piece and the support, and the peeling force was 13.1N. From this result, the first peel force of the semiconductor process sheet of Example 4 was determined to be a value larger than 13.1 N, which is the peel force between the test piece and the support where interfacial peeling occurred.

(2) Peeling force of the thermosetting resin layer to the double-sided adhesive sheet (second peeling force)
A test piece with a size of 20 mm width x 100 mm length was cut out from the semiconductor process sheets obtained in Examples and Comparative Examples. Next, this test piece was placed in an oven at 130° C., and the thermosetting resin layer was cured by adjusting the time (adjusted in the range of 10 seconds to 2 hours) to achieve a predetermined degree of curing. . Then, using a tensile tester (trade name "Autograph AG-X", manufactured by Shimadzu Corporation), the test piece was peeled at 23°C, a peeling angle of 180°, and a tensile speed of 300 mm/min. A test was conducted to measure the peeling force (second peeling force) of the thermosetting resin layer to the double-sided adhesive sheet in the semiconductor process sheets of Examples and Comparative Examples.

(3) Peeling force of the thermosetting resin layer against silicone after curing (third peeling force)
A test piece with a size of 20 mm width x 100 mm length was cut out from the thermosetting resin layer obtained in the examples and comparative examples. Next, the test piece was bonded to the mirror surface side of a silicon plate (unground bare wafer sold by Tokyo Kako Co., Ltd.) with the surface provided by the thermosetting resin layer. Further, the test piece was bonded to a support using the adhesive surface provided by the double-sided adhesive sheet surface. The bonding was performed by pressing a 2 kg hand roller back and forth once. Next, the thermosetting resin layer was cured by heating at 150° C. for 3 hours. Then, using a tensile testing machine (trade name "Autograph AG-X", manufactured by Shimadzu Corporation), the test piece was subjected to a peel test at 23°C, a peel angle of 180°, and a tensile speed of 300 mm/min. I did it. As a result, interfacial peeling occurred between the test piece and the support, and the peeling force was 13.1N. From these results, we determined that the peeling force (third peeling force) of the cured thermosetting resin layer against the silicon plate in the semiconductor process sheets of Examples and Comparative Examples was determined by the peeling force between the test piece and the support where interfacial peeling occurred. It was determined that the value was larger than 13.1N.

(4) Peeling force of double-sided adhesive sheet against silicone (fourth peeling force)
A test piece with a size of 20 mm width x 100 mm length was cut out from the double-sided pressure-sensitive adhesive sheets obtained in Examples and Comparative Examples. Next, the test piece was bonded to the mirror surface side of a silicon plate (unground bare wafer sold by Tokyo Kako Co., Ltd.) using the adhesive surface provided by the heat-foamed adhesive layer. This bonding was performed by pressing a 2 kg hand roller back and forth once. Then, using a tensile testing machine (trade name "Autograph AG-X", manufactured by Shimadzu Corporation), the test piece was subjected to a peel test at 23°C, a peel angle of 180°, and a tensile speed of 300 mm/min. The peeling force (fourth peeling force) of the double-sided adhesive sheet against the silicon plate in the semiconductor process sheets of Examples and Comparative Examples was measured.

(5) Glass transition temperature A test piece with a width of 5 mm x length of 30 mm was cut out from the thermosetting resin layer obtained in the examples and comparative examples, and the test piece was set so that the distance between the chucks was 20 mm. , the largest loss tangent (tan δ) when measured using a dynamic viscoelasticity measurement device "RSA III" (manufactured by TA Instruments) at a temperature range of -20 to 260°C and a heating rate of 10°C/min. The peak temperature was taken as the glass transition temperature.

(6) Tack strength of thermosetting resin layer One PET separator of the thermosetting resin layer obtained in Examples and Comparative Examples was peeled off, and double-sided adhesive tape was attached to the peeled side of the PET separator using a hand roller. Attach the double-sided tape side to a 25 mmΦ parallel plate for the compression jig of the dynamic viscoelasticity measurement device "RSA III" (manufactured by TA Instruments), cut off the thermosetting resin layer and double-sided adhesive tape that protruded from the plate, Peel off the other PET separator and set it on the lower side of the device so that the peeled side faces upward. Next, set an 8mmΦ SUS plate on the upper side, close the furnace and let it stand until the temperature reaches 40℃, press the upper plate against the lower plate for 1 second so that a load of 100g is applied, then put the plate on the upper side. The tack force was defined as the load applied to the upper plate when the thermosetting resin sheet was peeled off from the upper plate when the sheet was lifted and pulled apart.

(7) Curing start temperature of thermosetting resin layer 4 mg was cut from the thermosetting resin layer obtained in the examples and comparative examples, packed in an aluminum pan (manufactured by TA Instruments), and measured using a differential scanning calorimeter "DSC Q2000". (manufactured by TA Instruments), measurement was carried out at a heating rate of 10° C./min in a temperature range of 0° C. to 300° C., and the rising temperature of the exothermic peak was taken as the reaction initiation temperature.

(8) Elastic modulus after curing A test piece with a width of 5 mm x length of 30 mm was cut out from the thermosetting resin layer obtained in the Examples and Comparative Examples, and then this test piece was placed in an oven at 130°C. The thermosetting resin layer was cured by adjusting the time (adjusted within the range of 10 seconds to 2 hours) to achieve a predetermined degree of curing. The test piece after the hardening treatment was set so that the distance between the chucks was 20 mm, and the temperature range was -20 to 260°C with increasing temperature using a dynamic viscoelasticity measuring device "RSA III" (manufactured by TA Instruments). The storage elastic modulus E' at 25° C. when measured at a rate of 10° C./min was obtained as the elastic modulus after curing.

(9) Shear adhesive force of thermosetting resin layer to silicon (first shear adhesive force)
A thermosetting resin layer having a size of 3 mm in width x 3 mm in length was cut out from the thermosetting resin layer obtained in Examples and Comparative Examples. In addition, a silicon plate (unground bare wafer sold by Tokyo Kako Co., Ltd., thickness 500 μm) with a width of 10 mm and a length of 10 mm was prepared, as well as silicon chips cut into pieces with a width of 3 mm and a length of 3 mm. . Then, the cut out thermosetting resin layer and the silicon chip cut into pieces of 3 mm width x 3 mm length were bonded together under conditions of a temperature of 70°C and a pressure of 0.5 MPa, so that the thermosetting resin layer and the silicon chip were bonded together. A laminated test piece (width 3 mm x length 3 mm) was prepared. The above test piece was pasted onto a silicon plate (thickness 500 μm x width 10 mm x width 10 mm) placed on a hot plate (70°C) so that the surface on the thermosetting resin layer side was in contact. I pressed it and crimped it. Next, this test piece was placed in an oven at 130° C., and the thermosetting resin layer was cured by adjusting the time (adjusted in the range of 10 seconds to 2 hours) to achieve a predetermined degree of curing. . This laminate of silicon plate/thermosetting resin layer/silicon chip was measured at a temperature of 23°C using a shear adhesion measuring device (product name "DAGE4000", manufactured by Nordson). The shear adhesive force (first shear adhesive force) was measured by moving the jig under the following conditions: the height of the lower surface of the jig was 80 μm (height from the silicon plate), the speed was 500 μm/sec, and the amount of movement was 500 μm.

(10) Shear adhesive force of thermosetting resin layer to double-sided adhesive sheet (second shear adhesive force)
The double-sided pressure-sensitive adhesive sheets obtained in Examples and Comparative Examples were laminated onto the silicon plate (500 μm thick x 10 mm wide x 10 mm wide) prepared in the first shear adhesive strength measurement. Then, the test piece prepared in the first shear adhesive strength measurement was pasted onto the double-sided pressure-sensitive adhesive sheet in such a manner that the surface on the thermosetting resin layer side was in contact with the sheet, and was pressed by hand to pressure-bond the sheet. Next, this laminate (silicon plate/double-sided adhesive sheet/thermosetting resin layer/silicon chip laminate) was placed in an oven at 130°C for a period of time (10 seconds) to achieve a predetermined degree of curing. The thermosetting resin layer was cured by adjusting the temperature within a range of 2 hours. This laminate of silicone plate/double-sided adhesive sheet/thermosetting resin layer/silicon chip was measured at a temperature of 23°C using a shear adhesion measuring device (trade name "DAGE4000", manufactured by Nordson). Shear adhesive force (second shear adhesive force) was obtained by moving the silicon chip with the jig at a height of 80 μm at the bottom of the jig (height from the double-sided adhesive sheet), a speed of 500 μm/sec, and a movement amount of 500 μm. was measured.

(11) Shear adhesive force of the thermosetting resin layer to silicon after curing (third shear adhesive force)
The silicon plate/thermosetting resin layer/silicon chip laminate prepared in the first shear adhesive strength measurement was heated at 150°C for 3 hours to thermoset the thermosetting resin layer, and the shear adhesive strength measuring device (trade name "DAGE4000", manufactured by Nordson), the silicon chip was placed at a temperature of 23°C, at a height of 80 μm (height from the silicon plate) at the bottom of the jig, and at a speed of 500 μm/sec. The shear adhesive force (third shear adhesive force) was measured by moving the jig under the condition that the amount of movement was 500 μm.

(12) Shear adhesive force of double-sided adhesive sheet to silicone (4th shear adhesive force)
The double-sided pressure-sensitive adhesive sheets obtained in Examples and Comparative Examples were laminated onto the silicon plate (500 μm thick x 10 mm wide x 10 mm wide) prepared in the first shear adhesive strength measurement. Then, the silicon chip (thickness: 500 μm x width: 3 mm x width: 3 mm) prepared in the measurement of the first shear adhesive strength was bonded onto the double-sided pressure-sensitive adhesive sheet and pressed by hand. This laminate of silicon plate/double-sided adhesive sheet/silicon chip was measured using a shear adhesion measuring device (product name "DAGE4000", manufactured by Nordson) at a temperature of 23°C. The shear adhesive force (fourth shear adhesive force) was measured by moving the jig at a height of 80 μm at the lower surface (height from the double-sided adhesive sheet), a speed of 500 μm/sec, and a movement amount of 500 μm.

(13) Misalignment of semiconductor chips The heat-foamable adhesive layer surfaces of the semiconductor process sheets obtained in Examples and Comparative Examples were bonded to a disc-shaped silicon plate (diameter 300 mm) using a laminator, and then the silicon plate The portion of the semiconductor process sheet that protruded from the outer periphery was cut off to produce a laminate of silicon plate/double-sided adhesive sheet/thermosetting resin layer. Chips (silicon chips cut into pieces of 10 mm width x 10 mm length; thickness 100 μm) are placed in the thermosetting resin layer of the laminate at the center of the laminate and at a distance of 70 mm from each side of the chip in the center. Using a flip chip bonder (trade name "FC3000W", manufactured by Toray Engineering Co., Ltd.), the film was attached to the four locations under conditions of a temperature of 23° C. (room temperature), a collet temperature of 70° C., and a load of 10 N. Next, the laminate was placed in an oven at 130° C., and the thermosetting resin layer was cured by adjusting the time (adjusted within the range of 10 seconds to 2 hours) so that a predetermined degree of curing was achieved. Then, using a CNC image measuring device (trade name "QUICKVISION PRO", manufactured by Mitutoyo Co., Ltd.), the coordinates of each chip were determined from the surface where the chips were bonded together, and the position of this chip was set as the initial position. Thereafter, using a sealing sheet (product name "AS-110AB", manufactured by Nitto Denko Corporation, thickness 200 μm), the temperature was The chip was sealed under conditions of 90° C. and a load of 50 kN to obtain a sealed body with a sealing layer thickness of 200 μm. The sealed body was thermally cured by heating at 150° C. for 1 hour to obtain a cured sealed body. Place the cured sealing object on a hot plate heated to 180°C to foam (thermally expand) the heat-foamable adhesive layer of the double-sided adhesive sheet, peel off the silicone plate, and then heat the double-sided adhesive sheet. The laminate of [thermosetting resin layer/chip/sealing layer] was peeled off from the curable resin layer, and the thermosetting resin layer was removed by polishing to expose the surface of the chip. Thereafter, the coordinates of each chip were determined from the chip exposed surface side using the CNC image measuring device, and the position of this chip was determined as the position after sealing and curing. Then, the average value of the distances that the chips moved from the initial position to the post-sealing and curing position was determined as the positional deviation distance for the four chips located away from the center.

(14) Warpage The thermosetting resin layer with a thickness of 40 μm obtained in the Examples and Comparative Examples was bonded to the ground surface of a silicon plate (diameter 300 mm) that had been ground into a disk shape with a thickness of 200 μm using a laminator, and then The portion of the thermosetting resin layer protruding from the outer periphery of the silicon plate was cut off to produce a silicon plate/thermosetting resin layer laminate. The laminate was heated in an oven at 130° C. for 2 hours to cure the thermosetting resin layer. Thereafter, the laminate was left on a flat desk at room temperature for 1 hour with the thermosetting resin layer facing up. Thereafter, the distance between the outer circumference of the disc of the laminate and the flat surface of the desk was measured, and the distance with the greatest difference (largest) was determined as the amount of warp correction.

X Semiconductor process sheet 10 Double-sided adhesive sheet 10a, 10b Adhesive surface 11 Base material 12 Adhesive layer (reduced adhesive force type adhesive layer)
13 Adhesive layer 20 Thermosetting resin layer 30' Sealing material 30 Sealing material section 40 Wiring structure section 41 External electrode C Semiconductor chip P Package

Claims (5)

A double-sided pressure-sensitive adhesive sheet having a laminated structure including at least a reduced-adhesive pressure-sensitive adhesive layer, a pressure-sensitive adhesive layer, and a base material located between these;
a thermosetting resin layer releasably adhering to at least one adhesive surface of the double-sided adhesive sheet,
In a substantially uncured state or cured state at at least one point, the following first peel force is 5N or more, and the following first peel force is greater than the following second peel force, and the first peel force is greater than the following second peel force, and A semiconductor process sheet characterized in that a ratio of peeling force to the second peeling force is 2 or more .
First peel force: Peel force in a peel test at a peel angle of 180° with respect to silicon of the thermosetting resin layer Second peel force: Peel angle of 180° with respect to the double-sided pressure-sensitive adhesive sheet of the thermosetting resin layer Peel force in peel test under conditions of 2. The semiconductor process sheet according to claim 1, wherein in the double-sided adhesive sheet, the adhesive force-reduced adhesive layer is a heat-foaming adhesive layer, and the adhesive layer is a non-adhesive-strength non-reduced adhesive layer. The semiconductor process sheet according to claim 1 or 2, wherein the following third peeling force in a cured state is 5N or more.
Third peeling force: Peeling force against silicon of the thermosetting resin layer in a peeling test under the condition of a peeling angle of 180° Before a sealing process in which a sealing material is supplied so as to embed the semiconductor chip placed on the thermosetting resin layer, and then the sealing material is cured, the thermosetting resin layer is semicirculated. The semiconductor process sheet according to any one of claims 1 to 3, which is used for curing or curing purposes. A semiconductor chip is placed on the thermosetting resin layer, and the thermosetting resin layer is semi-cured or hardened so that the first peeling force is 5N or more, and then the sealing step is performed. The semiconductor process sheet according to claim 4, which is used in.

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