JP2023076199A - Manufacturing method of semiconductor device - Google Patents

Abstract

To provide a method for facilitating removal of a plurality of semiconductor elements from an adhesive sheet.SOLUTION: A semiconductor device manufacturing method includes the steps of preparing a sheet including an ultraviolet light curing resin, and thermally expanded particles contained in the ultraviolet light curing resin, arranging a plurality of semiconductor elements on the sheet, reducing the adhesiveness of the sheet by heating the sheet and irradiating the sheet with ultraviolet light, and simultaneously adsorbing the plurality of semiconductor elements using an adsorption member and removing them from the sheet.SELECTED DRAWING: Figure 4

Description

The present disclosure relates to a method of manufacturing a semiconductor device.

It is known to use a UV tape or a foam tape in a method of manufacturing a semiconductor device. Furthermore, it is known to use an adhesive sheet in which UV tape and foam tape are laminated.

JP-A-2005-339502 JP 2005-129652 A

To provide a method for facilitating removal of a plurality of semiconductor elements from an adhesive sheet.

The present disclosure includes the following configurations.
preparing a sheet containing an ultraviolet light curable resin and thermally expanded particles contained in the ultraviolet light curable resin;
arranging a plurality of semiconductor elements on the sheet;
a step of reducing the adhesiveness of the sheet by heating the sheet and irradiating the sheet with ultraviolet light;
a step of simultaneously adsorbing the plurality of semiconductor elements using an adsorption member and removing them from the sheet;
A method of manufacturing a semiconductor device comprising:

According to an embodiment of the present disclosure, a method for facilitating removal of a plurality of semiconductor elements from an adhesive sheet is provided.

It is a schematic sectional view which shows one process of the manufacturing method of the semiconductor device concerning embodiment. It is a schematic sectional view which shows one process of the manufacturing method of the semiconductor device concerning embodiment. It is a schematic sectional view which shows one process of the manufacturing method of the semiconductor device concerning embodiment. It is a schematic sectional view which shows one process of the manufacturing method of the semiconductor device concerning embodiment. It is a schematic sectional view which shows one process of the manufacturing method of the semiconductor device concerning embodiment. It is a schematic sectional view which shows one process of the manufacturing method of the semiconductor device concerning embodiment. It is a schematic sectional view which shows one process of the manufacturing method of the semiconductor device concerning embodiment. 1 is a schematic top view showing an example of a semiconductor device according to an embodiment; FIG. It is a schematic top view which shows one process of the manufacturing method of the semiconductor device concerning embodiment. It is a schematic sectional view which shows one process of the manufacturing method of the semiconductor device concerning embodiment. It is a schematic sectional view which shows one process of the manufacturing method of the semiconductor device concerning embodiment. It is a schematic top view which shows one process of the manufacturing method of the semiconductor device concerning embodiment.

The present invention will now be described in detail with reference to the drawings. In the following description, terms indicating specific directions and positions (e.g., "upper", "lower", and other terms including those terms) are used as necessary, but the use of these terms is These terms are used to facilitate understanding of the invention with reference to the drawings, and the technical scope of the invention is not limited by the meaning of these terms. Also, parts with the same reference numerals appearing in a plurality of drawings indicate the same or equivalent parts or members.

Further, the embodiments shown below are examples of semiconductor devices for embodying the technical idea of the present invention, and the present invention is not limited to the following. In addition, unless there is a specific description, the dimensions, materials, shapes, relative arrangements, etc. of the components described below are not intended to limit the scope of the present invention, but are intended to be examples. It is intended. Moreover, the content described in one embodiment can also be applied to other embodiments. Also, the sizes and positional relationships of members shown in the drawings may be exaggerated for clarity of explanation.

In the present disclosure, a method for manufacturing a semiconductor device includes the following steps.
preparing a sheet containing an ultraviolet light curable resin and thermally expanded particles contained in the ultraviolet light curable resin;
arranging a plurality of semiconductor elements on a sheet;
a step of reducing the adhesiveness of the sheet by heating the sheet and irradiating the sheet with ultraviolet light;
a step of simultaneously adsorbing a plurality of semiconductor elements using an adsorption member and removing them from the sheet;
A method of manufacturing a semiconductor device comprising:
Each step will be described in detail below.

(Step of preparing sheet)
First, the sheet 10 is prepared. The sheet 10 is an adhesive sheet containing an ultraviolet light curable resin 11 and a plurality of thermally expanded particles 12 contained in the ultraviolet light curable resin 11, as shown in FIG. 1A. The sheet 10 has an upper surface 10U on which a semiconductor element is placed and a lower surface 10D opposite to the upper surface 10U.

In addition to the sheet 10 exhibiting adhesiveness described above, the sheet 10 may include a non-adhesive support member on the side of the lower surface 10D on which the semiconductor element is not placed. For example, as shown in FIG. 1B, the adhesive sheet 10 can be placed on the upper surface 10U on which the semiconductor element is placed, and the support member 30 can be placed on the lower surface 10D on which the semiconductor element is not placed. By using such a laminated sheet, it is possible to suppress adhesion of unnecessary foreign matter or the like to the lower surface 10D of the adhesive sheet 10 . The support member 30 may include materials such as PET, PI, PO, and PVC, for example.

The sheet 10 has tackiness before being irradiated with ultraviolet light or before being heated. In this state, the adhesive strength of the sheet is, for example, about 300 mN/25 mm to 10000 mN/25 mm. Further, the surface roughness Sa of the sheet 10 is, for example, 0.05 μm to 1 μm before irradiation with ultraviolet light or before heating.

In addition, when a semiconductor element is placed on the upper surface 10U of the sheet 10, the adhesiveness and surface roughness indicate the adhesiveness or surface roughness of the upper surface 10U of the sheet 10. FIG. In that case, the lower surface 10D of the sheet 10 on which the semiconductor element is not mounted may exhibit the same adhesiveness or surface roughness as the upper surface 10U of the sheet 10, or may exhibit different adhesiveness or surface roughness. good.

The sheet 10 changes its state before and after irradiation with ultraviolet light or before and after heating, but the same term "sheet" is used.

The sheet 10 can be held by a jig such as a wafer ring that fixes the periphery of the sheet 10, for example. The sheet 10 can be adjusted according to the size of the jig. When wafer rings are used, the size of the sheet 10 can be 150 mm to 250 mm in diameter. The thickness of the sheet 10 can be, for example, about 10 μm to 50 μm. In the case of a laminated sheet comprising the sheet 10 and the support member 30, the laminated sheet can have a thickness of 30 μm to 200 μm.

Examples of the ultraviolet curable resin 11 forming the sheet 10 include acrylic resins.

The thermally expandable particles 12 contained in the ultraviolet light curable resin 11 include, for example, an elastic and thermally fusible substance or a substance that breaks due to thermal expansion. Examples of such materials include vinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, polyvinylidene chloride, polysulfone, and the like. Alternatively, the thermally expandable particles 12 may be a material that is easily gasified and expanded by heating. Examples of such materials include hydrocarbons such as isobutane, propane, and pentane. The particle size of the thermally expanded particles 12 can be, for example, 10 μm to 20 μm. The content of the thermally expandable particles 12 can be, for example, 10 parts by mass to 50 parts by mass with respect to 100 parts by mass of the ultraviolet light curing resin 11 . The shape of the thermally expanded particles 12 can be, for example, a spherical shape, an oblate shape, or the like. The thermally expanded particles 12 may be dispersed entirely in the ultraviolet light curable resin 11, or may be unevenly distributed on the upper surface side (the side on which the semiconductor element is placed). Alternatively, they may be unevenly distributed on the upper surface in the ultraviolet light curing resin 11 .

(Step of placing a semiconductor element)
Next, as shown in FIG. 2, a plurality of semiconductor elements 20 are arranged on the sheet 10 . Examples of the semiconductor element 20 include light-emitting elements such as LED chips and laser chips, and protective elements such as Zener diodes. The semiconductor element 20 may have a rectangular, triangular, hexagonal, or the like shape in plan view. The length of one side of the semiconductor element 20 can be, for example, about 50 μm to 1000 μm. The distance between the semiconductor elements 20 adjacent to each other can be 0 μm to 1000 μm, for example.

As the semiconductor element 20, for example, an LED chip having an upper surface with a pair of electrodes and a lower surface with no electrodes on the opposite side of the upper surface can be used. The semiconductor element 20 is placed on the sheet 10 such that the lower surface of the semiconductor element 20 and the upper surface (adhesive surface) 10U of the sheet 10 face each other. The upper surface of the semiconductor element 20 and the upper surface 10U of the sheet 10 may be opposed to each other.

The semiconductor element 20 can be selected through a process of inspecting characteristics before being placed on the sheet 10 . For example, when an LED chip is used as the semiconductor element 20 , the chromaticity, brightness, electrical characteristics, etc. of the LED chip are inspected, and the ranked chips can be placed at desired positions on the sheet 10 . Also, the characteristics of the semiconductor element 20 may be inspected after being placed on the sheet 10 . For example, when the semiconductor elements 20 placed on the sheet 10 are inspected and a semiconductor element 20 having an abnormal characteristic (defective element) is detected, the defective element is bonded using a mask or the like. It is possible to prevent ultraviolet light from being applied to the sheet 10 in the portion where it is. As a result, the adhesion of the sheet 10 to which the defective element is bonded can be suppressed from being lowered, and the adsorption member can make it difficult to remove the sheet 10 .

(Step of reducing adhesiveness)
Next, the tackiness of the sheet 10 is reduced. Specifically, the sheet 10 is heated and the sheet 10 is irradiated with ultraviolet light. In this case, the heating and the ultraviolet light irradiation may be started at the same time, the ultraviolet light irradiation may be started after the heating is started, or the ultraviolet light irradiation may be started and then the heating. may be started. The period for heating and the period for irradiating ultraviolet light may partially or entirely overlap, or may include a period for performing only one of them. For example, as shown in FIG. 3, the heating process is first performed, and then, as shown in FIG. 4, the ultraviolet light irradiation process is performed. By performing the heating step first, it becomes easier to form unevenness due to the thermally expanded particles before the ultraviolet light curing is cured by the ultraviolet light irradiation.

The heating temperature can be, for example, about 80.degree. C. to 150.degree. The heating time can be, for example, about 10 seconds to 180 seconds. In the heating step, for example, a method of placing the sheet 10 on a heating member 40 such as a heating plate and heating the sheet 10 from the lower surface side as shown in FIG. In addition, a heating member such as a heater is arranged on the upper surface side of the sheet 10 to heat the sheet 10 from above, or the inside of a heating member such as a heating container capable of accommodating the entire sheet 10 and the semiconductor element 20 It is also possible to use a method in which the sheet 10 is placed on the surface of the sheet 10 and heated from both the upper surface side and the lower surface side thereof. As for the region to be heated, at least a portion of the region in contact with the semiconductor element 20, that is, the portion overlapping the semiconductor element 20 in top view, may be heated, and the entire portion overlapping the semiconductor element 20 may be heated. is more preferred.

Heating increases the volume of the thermally expanded particles 12 in the ultraviolet light-curing resin 11 . That is, the inside of the sheet 10 is in a foamed state, and the surface (upper surface and/or lower surface) of the sheet 10 is uneven due to the foaming. For example, if the surface roughness Sa of the upper surface of the sheet 10 before heating is 0.05 to 1 μm, the surface roughness Sa of the upper surface of the sheet 10 after heating can be, for example, 3 μm to 15 μm. Further, in that case, the amount of unevenness after heating (the difference between the highest portion and the lowest portion) can be, for example, 10 μm to 100 μm. The adhesive strength of the sheet 10 after heating can be reduced, for example, by about 90% to 100% from the adhesive strength before heating.

As a light source for emitting ultraviolet light (ultraviolet rays), an LED (light emitting diode), a laser diode, a mercury lamp, a CCFL (cold cathode tube), or the like can be used. When an LED is used as the light source, the emission peak wavelength can be, for example, 200 nm to 370 nm. The output of the light source can be, for example, 30 mW/cm ² to 400 mW/cm ² or more. Also, the ultraviolet light irradiation time can be, for example, 1 second to 10 seconds. The region to be irradiated with ultraviolet light is preferably a region in contact with the semiconductor element 20, that is, a portion overlapping the semiconductor element 20 in a top view, at least a part of which is irradiated. Irradiation is more preferred. A mask or the like is used when the ultraviolet light is partially irradiated. Further, when a laser is used as a light source, ultraviolet light can be partially irradiated without using a mask.

It is preferable to irradiate the ultraviolet light from the lower surface 10D side of the sheet 10 of 10 (the side on which the semiconductor element is not placed). As a result, the portion of the sheet 10 that is in contact with the semiconductor element 20 can be efficiently irradiated with ultraviolet light, and the adhesiveness of the sheet 10 can be reduced. From this point of view, it is preferable to use a sheet 10 having a transmittance of at least 70% or more for ultraviolet light. When the sheet 10 is a laminated sheet provided with a support member 30 as shown in FIG. 1B, it is preferable that the support member 30 also has a transmittance of at least 70% or more of ultraviolet light. In addition, the ultraviolet light may be irradiated from the upper surface 10U side of the sheet 10 .

The ultraviolet curable resin 11 contained in the sheet 10 has adhesiveness of, for example, about 300 mN/25 mm to 10000 mN/25 mm before irradiation with ultraviolet light. Further, the adhesiveness of the UV light curable resin is lower than that before the UV light irradiation, and is, for example, about 10 mN/25 mm to 300 mN/25 mm.

The surface of the ultraviolet light curable resin 11 whose adhesiveness has been reduced by the irradiation of ultraviolet light in this way is provided with irregularities formed by the expansion of the thermally expanded particles 12 by heating, so that the sheet 10 and the semiconductor element 20 contact area is reduced. Therefore, the substantial tackiness of the surface of the sheet 10 is even lower than the tackiness described above.

(Process of removing from seat)
Next, a plurality of semiconductor elements 20 are simultaneously sucked and removed from the sheet 10 . For example, as shown in FIG. 5 , a plurality of semiconductor chips 20 are brought into contact with a suction member 60 having a plurality of vacuum suction holes, and the plurality of semiconductor chips 20 are simultaneously sucked and removed from the sheet 10 . Since the adhesiveness of the sheet 10 according to the present embodiment is reduced by heating and ultraviolet light irradiation, almost all of the plurality of semiconductor elements adsorbed at the same time or almost all of the semiconductor elements to be removed except for defective products are removed. can be removed. After the semiconductor element 20 on the sheet 10 is brought into contact with the semiconductor element 20 and adsorbed by the adsorption member 60, the presence or absence of abnormality is confirmed by the adsorption pressure, the adsorption flow rate, the image determination, and the like. For example, when a pressure lower than the set adsorption pressure is detected, there is a possibility that there is a semiconductor element 20 that has not been adsorbed. Also, if there is a semiconductor element that could not be removed, the semiconductor element is removed using another adsorption member as an additional step. In the present embodiment, it is possible to reduce the occurrence of such semiconductor elements that cannot be removed, so that additional removal processes can be reduced.

As the adsorption member 60, one having an adsorption surface provided with an adsorption port corresponding to the size and position of the semiconductor element 20, or one having an adsorption surface provided with a porous body can be used. Examples of porous bodies include sintered plastic porous bodies, sintered ceramic porous bodies, metal porous bodies, and the like. By using the adsorption member 60 having a porous material, it can be used even when the size and position of the semiconductor element 20 are different.

Also, the adsorption member 60 can have a heating function. For example, by heating after the adsorption member 60 is brought into contact with the semiconductor element 20, the sheet 10 can be heated from the upper surface 10U side to foam the sheet 10 or promote foaming. That is, the step of reducing the adhesiveness of the sheet 10 can be performed even after the adsorption member 60 and the semiconductor element 20 are brought into contact with each other. For example, the sheet 10 can be heated and the sheet 10 can be irradiated with ultraviolet light while the adsorption member 60 is in contact with the semiconductor element 20 on the sheet 10 . In this case, the adsorption member 60 may or may not perform the adsorption operation. Since unevenness is formed on the upper surface 10U of the sheet 10 by heating, the upper surface of the semiconductor element 20 may tilt. However, by contacting the semiconductor element 20 before the unevenness is formed by heating, and depending on the case, further adsorbing the semiconductor element 20, the adsorption surface of the adsorption member 60 and the upper surface of the semiconductor element 20 can be easily brought into contact with each other. can. Thereby, the semiconductor element 20 can be easily adsorbed. In addition, the semiconductor elements 20 can be transferred without changing the posture (inclination in the vertical direction or positional deviation in plan view) and the distance between the semiconductor elements. When using the adsorption member 60 equipped with a heater, for example, by using an adsorption member made of aluminum alloy or copper, the thermal conductivity can be increased, and the sheet 10 can be efficiently heated through the semiconductor element 20. be able to.

Also, a spacer having substantially the same height as the semiconductor element 20 may be arranged between the adsorption member 60 and the sheet 10 . Thereby, it is possible to suppress crushing of the thermally expanded particles expanded in the sheet 10 . In addition, without using spacers, the positions of the lower stage (heating stage, etc.) on which the sheet is placed and the upper stage (adsorption member, etc.) that is arranged on the upper surface side of the sheet and in contact with the semiconductor element are read by sensors. can be height controlled. Alternatively, it is possible to use a method in which the thickness of the semiconductor element is measured in advance, and the amount of pressure (working distance) of the attraction member set in advance is corrected according to the thickness of the semiconductor element. Such a method can also prevent the thermally expanded particles from being crushed in the sheet.

If the adsorption member 60 has a heating function, it can be used in combination with a heating member (heating table) on which the sheet 10 is placed. That is, the adsorption member 60 can be arranged on the upper surface side of the sheet 10 and the heating member can be arranged on the lower surface side of the sheet 10 . As a result, the sheet can be heated by both the heating member arranged on the lower surface side of the sheet 10 and the adsorption member arranged on the upper surface side of the sheet and having a heating function. By setting the temperature of the adsorption member 60 arranged on the upper surface side of the sheet 10 on which the semiconductor element 20 is arranged to be higher than the temperature of the heating member arranged on the lower surface side of the sheet 10, the temperature inside the sheet 10 is increased. can be made easy to maintain the foamed state of. It becomes easier to remove the semiconductor element. Moreover, the temperature at which the adsorption member starts adsorption is preferably lower than the temperature of the heating table. As a result, in the initial stage of heating, the upper surface of the sheet 10 is heated first, thereby suppressing preferential expansion of the expanded particles positioned on the upper surface. This makes it difficult for the previously expanded particles to be crushed.

For example, when the sheet 10 is composed of an acrylic resin as an ultraviolet curable resin and isobutane as thermally expanded particles, it is preferable to set the temperature of the heating table to about 110°C and the temperature of the adsorption member to about 145°C. . Moreover, it is preferable that the temperature of the adsorption member 60 is 30° C. to 60° C. when adsorption is started. Moreover, the heating time (the time during which the above set temperature is maintained on the heating member) is preferably about 120 seconds.

After the adsorption member 60 that has adsorbed the plurality of semiconductor elements 20 moves onto a desired member such as a wiring board, the adsorption operation is released. Thereby, a plurality of semiconductor elements 20 are arranged on the member at the same time. The adsorption member 60 releases the atmosphere or introduces compressed air after releasing the adsorption operation. As a result, it is possible to prevent the semiconductor element 20 from remaining stuck to the adsorption member 60.

The members used in the above steps are preferably grounded for static electricity. Moreover, it is preferable to use a static eliminator (ionizer) during the work. In particular, the adsorption surface of the adsorption member 60 can be made less susceptible to static electricity by using a conductive member such as a metal material. Non-conductive materials can be made less sensitive to static electricity by treating them with a conductive coating.

FIG. 7 shows an example of a semiconductor device 100 in which a plurality of semiconductor elements 20 are mounted on a wiring board 80. As shown in FIG. Here, an LED chip is used as the semiconductor element 20, and the semiconductor device 100 can be used as a light emitting module. A light-emitting module in which 1000 to 50000 semiconductor elements (LED chips) 20 are mounted on one wiring board 80 is a display capable of high-definition display, a lighting device capable of partial illumination, and capable of local dimming. It can be used for backlights of liquid crystal displays and the like. Although only the wiring board 80 and the semiconductor element (LED chip) 20 are shown in FIG. 7, the light emitting module may include other electronic components, sealing members, and the like.

For example, as shown in FIG. 8A, when about 10,000 semiconductor elements 20 are placed on a sheet 10 held by a wafer ring 70 having an inner diameter of 170 mm, heating and ultraviolet light irradiation can be performed. As shown in 8B and FIG. 8C, approximately all of them can be simultaneously removed by adsorption using the adsorption member 60 .

Then, as shown in FIG. 8D, the plurality of semiconductor elements 20 adsorbed by the adsorption member 60 are arranged on the wiring board 80 at the same time. Similar operations can be repeated according to the number of semiconductor elements 20 required for the semiconductor device 100 . A conductive joining member such as solder can be arranged in advance on the wiring board 80 . Alternatively, as the semiconductor element 20, one provided with a conductive bonding member may be used. Alternatively, the wiring board 80 and the semiconductor element 20 may be electrically joined by plating after the semiconductor element 20 is arranged on the wiring board 80 .

INDUSTRIAL APPLICABILITY Embodiments of the present disclosure are useful in manufacturing a semiconductor device including a step of removing a plurality of semiconductor elements from a sheet by adsorbing them at the same time.

DESCRIPTION OF SYMBOLS 10... Sheet 11... Ultraviolet light curing resin 12... Thermal expansion particle 10U... Upper surface of sheet 10D... Lower surface of sheet 20... Semiconductor element 30... Support member 40... Heating member 50... Ultraviolet light device 60... Adsorption member 70... Wafer ring 80 ... wiring board 100 ... semiconductor device

Claims (6)

preparing a sheet containing an ultraviolet light curable resin and thermally expanded particles contained in the ultraviolet light curable resin;
arranging a plurality of semiconductor elements on the sheet;
a step of reducing the adhesiveness of the sheet by heating the sheet and irradiating the sheet with ultraviolet light;
a step of simultaneously adsorbing the plurality of semiconductor elements using an adsorption member and removing them from the sheet;
A method of manufacturing a semiconductor device comprising: 2. The method of manufacturing a semiconductor device according to claim 1, wherein the step of reducing the adhesiveness is performed after bringing the adsorption member and the plurality of semiconductor elements into contact with each other. 3. The manufacturing of a semiconductor device according to claim 1, wherein the adsorption member has a heating function, and the step of reducing the adhesiveness includes a step of heating the upper surface of the sheet with the adsorption member. Method. The sheet is heated by both a heating member arranged on the lower surface side of the sheet and the adsorption member arranged on the upper surface side of the sheet and having a heating function, and the set temperature of the adsorption member is 4. The method of manufacturing a semiconductor device according to claim 3, wherein the temperature is set higher than the set temperature of said heating member. 5. The method of manufacturing a semiconductor device according to claim 4, wherein a temperature at which said adsorption member starts adsorption is a temperature lower than a set temperature of said heating member. 6. The method of manufacturing a semiconductor device according to claim 1, wherein a spacer having substantially the same height as said semiconductor element is arranged between the upper surface of said sheet and said adsorption member.

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