JP2013093490A - Manufacturing method and manufacturing device for semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To separate a substrate formed with a semiconductor element from a support substrate while more significantly suppressing a semiconductor element from being damaged.SOLUTION: The manufacturing method for semiconductor device includes a process for pasting a surface of a semiconductor substrate 10 formed with a semiconductor element on the front face side and one of two faces of a support substrate 12 for supporting the semiconductor substrate 10 onto each other, and a process for separating a first substrate from a second substrate while relatively moving the semiconductor substrate 10 and the support substrate 12, and a wire 20.

Description

  FIELD Embodiments described herein relate generally to a semiconductor device manufacturing method and a semiconductor manufacturing apparatus.

  In manufacturing a semiconductor device, other necessary processes are performed in a state where a device surface formed on a semiconductor wafer is adhered to a support substrate. Then, after the necessary process is completed, the semiconductor wafer is separated from the support substrate. Use a thermoplastic adhesive to bond the semiconductor wafer and the support substrate, and when peeling off, heat the semiconductor wafer and the support substrate with a heater, etc., and place one in the direction parallel to the bonding surface. Both can be separated by moving (sliding).

  However, in this method, since it takes a long time for heating, the device and the bump structure formed on the semiconductor wafer are damaged. In addition, the sliding causes shear stress to act on the elements and bumps on the surface side of the semiconductor wafer via an adhesive, which causes deterioration of the characteristics of the semiconductor device. Since these damage and deterioration affect the yield of the semiconductor device, it is required to establish a separation method that does not damage the device and the bump structure in a short time.

JP 2007-294717 A

  Embodiments of the present invention provide a method of manufacturing a semiconductor device and a manufacturing apparatus thereof capable of separating a substrate on which a semiconductor element is formed and a support substrate while reducing damage to the semiconductor element and the like. With the goal.

The method of manufacturing a semiconductor device according to the embodiment includes a surface of a first substrate having a semiconductor element formed on a surface side, and one surface of two surfaces of a second substrate that supports the first substrate. A step of separating the first substrate and the second substrate while relatively moving the first substrate and the second substrate and the wire;
It is provided with.

  The semiconductor manufacturing apparatus according to the embodiment includes a stage, a substrate holding unit, a wire holding unit, and a driving unit. The stage mounts a second substrate that supports the first substrate, on which a first substrate having a semiconductor element formed on the front surface side is attached with the front surface facing. The substrate holding unit holds the back surface of the first substrate. The wire holding unit holds a wire that separates the first substrate and the second substrate. The driving unit relatively moves the wire and the attached first and second substrates.

It is a flowchart figure which shows the principal part process of the manufacturing method of the semiconductor device in 1st Embodiment. It is process sectional drawing of the manufacturing method of the semiconductor device in 1st Embodiment. It is a front conceptual diagram which shows the structure of the manufacturing apparatus of the semiconductor device in 1st Embodiment. It is a top surface conceptual diagram for demonstrating operation | movement of the manufacturing apparatus of the semiconductor device in 1st Embodiment. It is sectional drawing for demonstrating the isolation | separation method in 1st Embodiment. It is sectional drawing which shows an example of the wire in 1st Embodiment. It is a top surface conceptual diagram which shows the structure of the manufacturing apparatus of the semiconductor device in 2nd Embodiment. It is an upper surface conceptual diagram which shows the structure of the manufacturing apparatus of the semiconductor device in 3rd Embodiment. It is an upper surface conceptual diagram which shows the structure of the manufacturing apparatus of the semiconductor device in 4th Embodiment.

(First embodiment)
The first embodiment will be described below with reference to the drawings. FIG. 1 is a flowchart showing main steps of the semiconductor device manufacturing method according to the first embodiment. In FIG. 1, the manufacturing method of the semiconductor device in the first embodiment includes a support substrate bonding step (S102), a semiconductor substrate thinning step (S104), a through electrode (TSV) forming step (S106), and a separation step. A series of steps (S108) is performed. Here, TSV (Through-Silicon Via) is a term indicating an electrode penetrating a silicon semiconductor substrate in the thickness direction in a narrow sense. However, in this specification, for the convenience of explanation, it is used as a term indicating a general through electrode that penetrates a semiconductor substrate including a semiconductor material other than silicon (for example, a compound semiconductor material such as GaAs).

  FIG. 2 is a process cross-sectional view of the semiconductor device manufacturing method according to the first embodiment. FIG. 2 shows from the support substrate bonding step (S102) to the TSV formation step (S106).

  In FIG. 2A, as the support substrate bonding step (S102), the surface of the semiconductor substrate 10 (first substrate) on which the semiconductor element is formed on the front surface side, and the support substrate 12 that supports the semiconductor substrate 10 (second substrate). The surface of the substrate). On the surface of the semiconductor substrate 10, bumps and the like are formed that serve as contact points for conduction with other semiconductor substrates when a semiconductor chip or another semiconductor substrate is stacked to form a multilayer chip.

  As the semiconductor substrate 10, for example, a 300 mm silicon wafer is used. And it adhere | attaches with the support substrate 12 arrange | positioned at the surface side in which this semiconductor element was formed. The support substrate 12 is bonded so that one of the two surfaces faces the semiconductor substrate 10. By supporting the semiconductor substrate 10 with the support substrate 12, it is possible to prevent the semiconductor substrate 10 from being cracked when the thickness of the semiconductor substrate 10 is reduced later or when TSVs are formed.

  As a material of the support substrate 12, silicon, silicon carbide (SiC), sapphire, or the like is preferable. In addition, it is also preferable to use a compound semiconductor wafer such as gallium phosphide (GaP), gallium arsenide (GaAs), indium phosphide InP (InP), or gallium nitride (GaN), glass, or the like.

  The semiconductor substrate 10 and the support substrate 12 are bonded with an adhesive. Examples of the adhesive include epoxy resins, bismaleimide-triazine resins, PEEK resins, butadiene resins, other polyolefins such as polyethylene and polypropylene, polydienes such as polybutadiene, polyisoprene, and polyvinylethylene, polymethyl acrylate, and polymethyl. Contains acrylic resins such as methacrylate and polyacrylate, polystyrene derivatives, polyacrylonitrile derivatives such as polyacrylonitrile and polymethacrylonitrile, polyacetals such as polyoxymethylene, polyethylene terephthalate, polybutylene terephthalate, and aromatic polyesters Polyesters, polyarylates, aromatic polyamides such as para- and meta-aramid resins, and polyamides such as nylon, Imidoamides, polyimides, aromatic polyethers such as poly-p-phenylene ether, polyethersulfones, polysulfones, polysulfides, fluorine-based polymers such as polytetrafluoroethylene, polybenzoxazoles, polybenzothiazoles, poly Benzimidazoles, polyphenylenes such as polyparaphenylene, polyparaphenylene benzobisoxazole derivatives, polyparaphenylene vinylene derivatives, polysiloxane derivatives, novolac resins, melamine resins, urethane resins, polycarbodiimide resins, other silicones System materials and the like.

  In FIG. 2B, as the semiconductor substrate thinning step (S104), the back surface of the semiconductor substrate 10 (the surface on which the semiconductor element is not formed) with the semiconductor substrate 10 and the support substrate 12 attached. To reduce the thickness of the semiconductor substrate 10. For example, the thickness may be reduced by polishing by chemical mechanical polishing (CMP) or the like.

  In FIG. 2C, as a TSV forming step (S106), a contact (electrode) 16 is formed so as to penetrate the semiconductor substrate 10. For example, first, a via hole is formed at a position where an electrode is to be formed, and a barrier metal film is formed on the side wall and bottom surface in the via hole. Then, after the via hole is filled with a conductive material, excess conductive material and the barrier metal film outside the via hole may be removed by polishing. Examples of the material of the barrier metal film include tantalum-based tantalum-containing materials such as tantalum (Ta) and tantalum nitride (TaN), titanium-based titanium-containing materials such as titanium (Ti) and titanium nitride (TiN), and tungsten nitride (WN). Or a laminated film using a combination of Ta and TaN or the like. Suitable materials for the conductive material include copper (Cu), aluminum (Al), tungsten (W), and the like.

  The order of the semiconductor substrate thinning step (S104) and the TSV forming step (S106) may be reversed. In other words, either via first / via last may be used.

  Then, after the necessary processes such as the semiconductor substrate thinning step (S104) and other, for example, the TSV formation step (S106) are completed, the semiconductor substrate 10 is separated from the support substrate 12. Here, as described above, in the separation method in which the semiconductor substrate 10 and the support substrate 12 are separated by moving (sliding) one of the semiconductor substrate 10 and the support substrate 12 in a direction parallel to the bonding surface, as described above, devices and bumps are used. In some cases, the structure was damaged. Further, there are cases where shearing stress acts on elements or bumps on the surface side of the semiconductor wafer through an adhesive due to the slide, and the characteristics of the semiconductor device deteriorate. Therefore, in the first embodiment, separation is performed as follows.

  As the separation step (S108), the semiconductor substrate 10 and the support substrate 12 are separated using a wire.

  FIG. 3 is a front conceptual diagram showing the configuration of the semiconductor manufacturing apparatus according to the first embodiment. FIG. 3 shows a substrate separating apparatus 100 as an example of a semiconductor manufacturing apparatus. In the substrate separating apparatus 100, a support substrate 12 that supports the semiconductor substrate 10 on which the semiconductor substrate 10 is attached with the front side facing is placed on a stage 102. The back surface of the support substrate 12 is sucked and held on the stage 102 by, for example, a vacuum chuck mechanism. Then, the back surface of the semiconductor substrate 10 is held by the holder 104. The holder 104 is an example of a substrate holding unit. The back surface of the semiconductor substrate 10 is sucked and held on the lower surface of the holder 104 by, for example, a vacuum chuck mechanism. As described above, the bonded semiconductor substrate 10 and support substrate 12 are sandwiched between the stage 102 and the holder 104. A slight tension may be applied between the stage 102 and the holder 104 by the holder 104 so that the substrate is more easily separated during the separation. In order to hold the substrate for each of the stage 102 and the holder 104, a vacuum chuck is used here as an example. However, the present invention is not limited to this. Other chucking methods may be used as long as the corresponding substrates can be handled. For example, you may stick with a tape etc.

  In the substrate separating apparatus 100, the wire 20 is held by the wire holding unit 106. The wire holding part 106 is stretched so that the wire 20 is not loosened by holding the wire 20 so as to apply tension. The wire 20 is held parallel to the surfaces of the semiconductor substrate 10 and the support substrate 12 at the height position of the adhesive 14 between the semiconductor substrate 10 and the support substrate 12. Disconnect.

  FIG. 4 is a top conceptual view for explaining the operation of the semiconductor device manufacturing apparatus according to the first embodiment. In FIG. 4, the semiconductor substrate 10 and the support substrate 12 are separated from each other by relatively moving the wire 20 stretched so as not to be loosened, and the semiconductor substrate 10 and the support substrate 12 attached. In FIG. 4, the drive unit 108 moves linearly while holding the wire holding unit 106 on the rail 110 arranged in parallel to both side surfaces of the semiconductor substrate 10 and the support substrate 12, so that the wire 20 is bonded to the adhesive 14. Proceed while cutting.

  Furthermore, it is also preferable that, for example, an end portion of the wire 20 is connected to the ultrasonic vibration device 112 so that the semiconductor substrate 10 and the support substrate 12 are separated while the wire 20 is ultrasonically vibrated. For example, the wire 20 may be vibrated in the longitudinal direction. By ultrasonic vibration, for example, frictional heat is generated, and the adhesive can be softened by local heating by frictional heat. As a result, the separation can be facilitated without applying a large thermal stress to the device or the bump structure. For example, it is preferable to apply a frequency vibration of 20 kHz or more to the wire.

  FIG. 5 is a cross-sectional view for explaining the separation method according to the first embodiment. As shown in FIG. 5A, first, the wire 20 is disposed at the height position of the adhesive 14 between the semiconductor substrate 10 and the support substrate 12. In particular, it is preferable that the lower end of the wire 20 is disposed so as to be substantially at the same position as the surface of the support substrate 12. By adopting such an arrangement position, the thickness of the wire 20 can be increased to, for example, ½ of the thickness of the adhesive material 14. On the surface of the semiconductor substrate 10, irregularities due to semiconductor elements are formed. Therefore, a semiconductor element may be formed up to, for example, 1/2 of the thickness of the adhesive 14 on the semiconductor substrate 10 side. Therefore, the semiconductor element can be prevented from being damaged by setting the thickness of the wire 20 to, for example, ½ or less of the thickness of the adhesive 14. For example, the thickness is preferably 10 to 100 μm.

  Then, as shown in FIG. 5B, by cutting the inside of the adhesive 14 while moving the wire 20 along the surface of the support substrate 12, as shown in FIG. 12 can be separated.

  FIG. 6 is a cross-sectional view showing an example of a wire in the first embodiment. The wire 20 is preferably formed of a metal wire made of carbon steel or the like, a PTTA fiber, a PBO fiber, an aromatic polyamide copolymer, or a polymer material such as PET. The cross section of the wire 20 may be formed as a circle as shown in FIG. 6 (a), a diamond as shown in FIG. 6 (b), or a triangle as shown in FIG. 6 (c). In addition, a plurality of lines as shown in FIG. Alternatively, a hollow structure as shown in FIG. In the example of FIG. 6E, it is preferable that holes that are hollow from the outside are formed at a plurality of locations in the direction in which the wire 20 extends.

  As described above, in the first embodiment, the adhesive material 14 is cut with the wire 20. Thereby, the semiconductor substrate 10 and the support substrate 12 can be separated easily and without applying a force to the semiconductor element or the like. In other words, the semiconductor substrate 10 on which the semiconductor element is formed and the support substrate 12 can be separated while reducing damage to the semiconductor element or the like. Moreover, it can be made easier to cut by using ultrasonic vibration. As a result, the cutting time can be shortened.

(Second Embodiment)
In the first embodiment, the semiconductor substrate 10 and the support substrate 12 are separated by moving the wire 20 side, but the present invention is not limited to this. In the second embodiment, a configuration for moving the substrate side will be described. In the following, the contents other than those specifically described are the same as those in the first embodiment.

  FIG. 7 is a top conceptual view showing a configuration of a semiconductor device manufacturing apparatus according to the second embodiment. In FIG. 7, in the substrate separating apparatus 100, a driving unit 190 is connected to the stage 102. On the other hand, the wire holding part 106 held so as to apply tension to the wire 20 is fixed. It is also preferable that the semiconductor substrate 10 and the support substrate 12 be separated by moving the stage 102 linearly toward the wire 20 side by the driving unit 190 without moving the wire 20. Thus, the bonded semiconductor substrate 10 and support substrate 12 may be configured to proceed while the adhesive 14 is cut by the wire 20. In other words, the wire 20 stretched so as not to be loosened, and the bonded semiconductor substrate 10 and the support substrate 12 may be relatively moved. The apparatus can be configured more simply than when the wire holding unit 106 is moved.

(Third embodiment)
In the above-described embodiment, the example in which the wire 20 moves linearly in the direction orthogonal to the longitudinal direction of the wire 20 has been described, but the way of movement at the time of cutting is not limited thereto. In the following, the contents other than those specifically described are the same as those in the first embodiment.

  FIG. 8 is a conceptual top view showing a configuration of a semiconductor device manufacturing apparatus according to the third embodiment. In FIG. 8, in the substrate separating apparatus 100, one end of the wire 20 is fixed and the other end is held by the wire holding unit 106 so as not to be loosened. And the drive part 128 holding the wire holding part 106 advances the rail 120 on an arc centering on one end of the wire. Accordingly, the wire 20 advances between the semiconductor substrate 10 and the support substrate 12 while moving the other end in an arc shape with one end of the wire 20 as an axis. Thereby, the semiconductor substrate 10 and the support substrate 12 are separated.

  Further, it is also preferable to dispose a solvent rod 114 so that the solvent of the adhesive 14 is attached to the wire 20. For example, the wire 20 is immersed in the solvent bowl 114. Thereby, when the semiconductor substrate 10 and the support substrate 12 are separated, the solvent reaches the adhesive 14 through the wire 20 and can melt or soften the adhesive 14. In the example of FIG. 8, it is preferable that the solvent rod 114 is disposed on the shaft side where the movement range of the wire 20 is narrow because a small rod is sufficient. Further, as the structure of the wire 20, by making a structure in which a plurality of lines are brought together as shown in FIG. 6 (d) or a hollow structure as shown in FIG. The solvent can easily travel along the wire 20. Then, the solvent oozes out from the structure in which the plurality of lines in FIG. Alternatively, it oozes out from a hole (hole) provided in the hollow structure of FIG. Thus, by devising the structure of the wire 20, the solvent can be efficiently conveyed to the adhesive 14 side.

  The method of attaching the solvent to the wire 20 is not limited to the case of dipping. It may be dripped. Alternatively, it is also preferable to vaporize the solvent to generate vapor and expose the wire 20 to the vapor of the solvent.

(Fourth embodiment)
In the above-described embodiment, an example in which ultrasonic vibration or a solvent is used to soften the adhesive 14 has been described, but the present invention is not limited to this. In addition, the contents other than those specifically described below are the same as in any of the embodiments described above.

  FIG. 9 is a top conceptual view showing a configuration of a semiconductor device manufacturing apparatus according to the fourth embodiment. 9 is the same as FIGS. 3 and 4 except that the heater 116 is disposed at the other end of the wire 20 instead of the ultrasonic vibration device 114. It is also preferable that the semiconductor substrate 10 and the support substrate 12 are separated by linearly moving the wire 20 so as to pass between the semiconductor substrate 10 and the support substrate 12 while heating the wire 20 with the heater 116. . By heating the wire 20, the adhesive 14 that has touched the heated wire 20 can be softened. As a result, separation can be facilitated. Since the substrate is not directly heated, it is possible to prevent damage to semiconductor elements and bumps.

  The embodiment has been described above with reference to specific examples. However, the present invention is not limited to these specific examples. In the above-described example, the case where any one of the configuration for ultrasonically vibrating the wire 20, the configuration for attaching a solvent to the wire 20, and the configuration for heating the wire 20 with a heater has been described. Are also suitable. In the above-described example, the case where the semiconductor substrate 10 and the support substrate 12 are separated by one wire 20 has been described. However, the present invention is not limited to this, and the semiconductor substrate 10 and the support substrate 12 can be separated by two or more wires. May be separated. For example, you may make it cut toward the center part of a board | substrate with two wires from the both sides of a board | substrate. Thereby, the separation time can be shortened. In the above-described example, the case where the wire 20 is heated by the heater 116 has been described. However, the present invention is not limited to this, and a means for heating the wire 20 may be provided. For example, a high resistance material may be used for the wire 20 and a current may be passed through the wire 20 to cause the wire 20 itself to generate heat. Thereby, the heater 116 can be omitted.

  In addition, as to the thickness, size, shape, number, etc. of each substrate and film, those required in the semiconductor integrated circuit and various semiconductor elements can be appropriately selected and used.

  In addition, any semiconductor device manufacturing method that includes the elements of the present invention and whose design can be changed as appropriate by those skilled in the art is included in the scope of the present invention.

  Further, for simplification of explanation, processes for manufacturing other semiconductor devices are omitted, but it goes without saying that those methods are performed in manufacturing the semiconductor devices.

DESCRIPTION OF SYMBOLS 10 Semiconductor substrate, 12 Support substrate, 14 Adhesive material, 20 Wire, 100 Substrate separation apparatus, 102 Stage, 104 Holder, 106 Wire holding part, 108 Drive part, 112 Ultrasonic vibration apparatus, 114 Solvent soot, 116 Heater

Claims (6)

Attaching the surface of the first substrate on which the semiconductor element is formed on the surface side and one surface of the two surfaces of the second substrate supporting the first substrate using an adhesive; ,
Grinding the back surface of the first substrate to reduce the thickness of the first substrate in a state where the first substrate and the second substrate are attached;
Separating the first substrate and the second substrate while relatively moving the first substrate, the second substrate, and the wire;
A method for manufacturing a semiconductor device, comprising:
A method of manufacturing a semiconductor device, wherein the first substrate and the second substrate are separated from each other while ultrasonically vibrating the wire by using a solvent of the adhesive. Bonding the surface of the first substrate on which the semiconductor element is formed on the surface side and one of the two surfaces of the second substrate that supports the first substrate;
Separating the first substrate and the second substrate while relatively moving the first substrate and the second substrate and the wire;
A method for manufacturing a semiconductor device, comprising:   The method further comprises the step of grinding the back surface of the first substrate to reduce the thickness of the first substrate in a state where the first substrate and the second substrate are attached. Item 3. A method for manufacturing a semiconductor device according to Item 2.   4. The method of manufacturing a semiconductor device according to claim 2, wherein the first substrate and the second substrate are separated while ultrasonically vibrating the wire.   4. The method of manufacturing a semiconductor device according to claim 2, wherein the first substrate and the second substrate are separated while heating the wire. 5. A stage on which a first substrate on which a semiconductor element is formed on the surface side is attached with the surface side facing, the second substrate supporting the first substrate being placed;
A substrate holding part for holding the back surface of the first substrate;
A wire holding unit for holding a wire for separating the first substrate and the second substrate;
A drive unit for relatively moving the wire and the first and second substrates attached;
A semiconductor manufacturing apparatus comprising:

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