Semiconductor bonding device

Abstract

To provide a semiconductor bonding device capable of uniformly pressing a semiconductor chip against a substrate while stably attracting and holding the semiconductor chip.SOLUTION: A semiconductor bonding device includes: a porous plate-like member 80 made of a porous material having air permeability and having a first surface 81 and a second surface 82 opposite thereto that is in contact with the semiconductor chip CH; a base member 70 joined to the second surface of the porous plate-like member and provided with a first space 71 for introducing at least a positive pressure into a central region of the second surface of the porous plate-like member and a second space 72 for introducing at least a negative pressure into a peripheral region located outside the central region of the second surface of the porous plate-like member; a negative pressure supply part 61 that supplies the negative pressure to the second space of the base member to suck and hold the semiconductor chip by the porous plate-like member; and a positive pressure supply part 62 that supplies the positive pressure to the first space of the base member to deform the semiconductor chip sucked and held by the porous plate-like member into a convex shape.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to semiconductor bonding devices. [Background technology]

[0002] In response to the demand for thinner electronic devices, semiconductor chips are becoming thinner.

[0003] In this regard, Patent Document 1 below discloses a bonding device for bonding a thin semiconductor chip to a substrate. The bonding device described in Patent Document 1 suction-holds the semiconductor chip through first air holes formed in the peripheral region of the collet, blows air through second air holes formed in the central region to deform the central region of the semiconductor chip into a convex shape, and then performs bonding. This configuration prevents air from entering between the semiconductor chip and the substrate, reducing the occurrence of voids. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-303151 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the above-mentioned bonding apparatus, since a plurality of vent holes are formed in the bottom surface of the collet, there is a problem in that the semiconductor chip cannot be pressed evenly when bonding the semiconductor chip to the substrate.

[0006] Furthermore, in the bonding device, the pressure changes suddenly at the boundary between the first vent, which is supplied with negative pressure to hold the semiconductor chip by suction, and the space in the convex portion of the semiconductor chip, which is held at positive pressure by air blown through the second vent, which can cause a gap to form between the first vent and the semiconductor chip, allowing air to flow from the space in the convex portion toward the first vent, potentially causing vibration of the semiconductor chip.

[0007] The present invention has been made in view of the above-mentioned problems, and therefore an object of the present invention is to provide a semiconductor bonding device that can stably suck and hold a semiconductor chip and uniformly press the semiconductor chip against a substrate. [Means for solving the problem]

[0008] The above object of the present invention can be achieved by the following means.

[0009] (1) A semiconductor bonding device comprising: a porous plate-like member made of a porous material having air permeability and having a first surface that contacts a semiconductor chip and a second surface opposite the first surface; a base member bonded to the second surface of the porous plate-like member and having a first space for introducing at least a positive pressure into a central region of the second surface of the porous plate-like member and a second space for introducing at least a negative pressure into a peripheral region located outside the central region of the second surface of the porous plate-like member; a negative pressure supply unit that supplies negative pressure to the second space of the base member to adsorb and hold the semiconductor chip by the porous plate-like member; and a positive pressure supply unit that supplies positive pressure to the first space of the base member to deform the semiconductor chip adsorbed and held by the porous plate-like member into a convex shape.

[0010] (2) The semiconductor bonding apparatus described in (1) above, wherein the positive pressure supply unit includes a servo valve that combines positive pressure supplied from a positive pressure supply source and negative pressure supplied from a negative pressure supply source to adjust at least the positive pressure supplied to the first space of the base member.

[0011] (3) The semiconductor bonding apparatus according to (2) above, wherein the base member is attached to a lower portion of a housing of the bonding head, and the servo valve is disposed inside or near the housing of the bonding head.

[0012] (4) The semiconductor bonding apparatus according to (2) or (3) above, further comprising a throttle valve disposed between the servo valve and the first space.

[0013] (5) The semiconductor bonding apparatus according to (2) or (3) above, further comprising a pressure sensor disposed between the servo valve and the first space, the output of the pressure sensor being fed back to the servo valve.

[0014] (6) The semiconductor bonding apparatus according to (2) or (3) above, further comprising a flow sensor disposed between the servo valve and the first space, the output of the flow sensor being fed back to the servo valve.

[0015] (7) A semiconductor bonding apparatus as described in (2) or (3) above, further comprising an electromagnetic valve disposed between the servo valve and the first space, for switching between a first state in which the first space is connected to the servo valve and a second state in which the first space is open to the atmosphere.

[0016] (8) The semiconductor bonding apparatus according to (2) or (3) above, further comprising a first regulator for adjusting the positive pressure supplied from the positive pressure supply source, and a second regulator for adjusting the negative pressure supplied from the negative pressure supply source.

[0017] (9) The semiconductor bonding apparatus according to (2) or (3) above, wherein the servo valve is configured to supply negative pressure to the first space during a period other than the period during which the semiconductor chip is being deformed into a convex shape.

[0018] (10) The semiconductor bonding apparatus according to (1), wherein the positive pressure supplying unit includes a pump that supplies positive pressure to the first space of the base member.

[0019] (11) The semiconductor bonding apparatus according to (10) above, wherein the base member is attached to a lower part of a housing of the bonding head, and the pump is disposed inside or near the housing of the bonding head.

[0020] (12) The semiconductor bonding apparatus according to (1) or (2) above, further comprising a shape sensor for measuring the shape of the semiconductor chip, and the measurement result of the shape sensor is fed back to the positive pressure supply unit.

[0021] (13) The semiconductor bonding apparatus according to (1) or (2) above, wherein the pore diameter of the porous material is smaller than the thickness of the semiconductor chip. [Effects of the Invention]

[0022] According to the semiconductor bonding apparatus of the present invention, it is possible to stably hold the semiconductor chip by suction and to uniformly press the semiconductor chip against the substrate. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a diagram showing a schematic configuration of a semiconductor bonding apparatus according to a first embodiment. [Figure 2] FIG. 2 is a diagram showing a schematic configuration of a joining head. [Figure 3A] FIG. 3 is a cross-sectional view showing a schematic configuration of a holding portion. [Figure 3B] FIG. 2 is a bottom view showing a schematic configuration of a base member. [Figure 4] FIG. 4 is a diagram showing the relationship between the input current to the servo valve and the supply pressure. [Figure 5] FIG. 10 is a diagram showing the relationship between the input current to the servo valve, the supply pressure, and the throttle valve. [Figure 6A] 1A and 1B are diagrams illustrating the force applied to the surface of a semiconductor chip by a semiconductor bonding device. [Figure 6B] 1 is a diagram showing the force applied to the surface of a semiconductor chip by a typical semiconductor bonding device. [Figure 7A] FIG. 10 is a diagram showing a pressure gradient on the surface of a holding portion in a semiconductor bonding apparatus. [Figure 7B]FIG. 10 is a diagram showing a pressure gradient on the surface of a holder in a typical semiconductor bonding apparatus. [Figure 8] 10A and 10B are diagrams for explaining vibration of a semiconductor chip; [Figure 9A] 10A and 10B are diagrams showing measurement results of the vibration state of a semiconductor chip. [Figure 9B] 10A and 10B are diagrams showing measurement results of the vibration state of a semiconductor chip. [Figure 10A] FIG. 10 is a cross-sectional view showing a schematic configuration of a holding portion according to a modified example. [Figure 10B] FIG. 10 is a bottom view showing a schematic configuration of a base member according to a modified example. [Figure 11A] FIG. 10 is a cross-sectional view showing a schematic configuration of a holding portion according to a modified example. [Figure 11B] FIG. 10 is a bottom view showing a schematic configuration of a base member according to a modified example. [Figure 12] FIG. 10 is a diagram showing a schematic configuration of a joining head according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following drawings, the same reference numerals refer to the same components, and the size of each component in the drawings may be exaggerated for clarity and convenience. Meanwhile, the embodiments described below are merely examples, and various modifications are possible from such embodiments.

[0025] Hereinafter, the terms "upper" and "above" may include not only what is directly above in contact with something, but also what is above without contact. Similarly, the terms "lower" and "below" may include not only what is directly below in contact with something, but also what is below without contact.

[0026] The singular expression includes the plural expression unless the context clearly dictates otherwise. Furthermore, when a part "includes," "comprises," or "has" a certain element, it does not mean that it excludes other elements, but that it may further include other elements, unless otherwise specified to the contrary.

[0027] Unless explicitly stated or stated to the contrary, steps constituting a method may be performed in any suitable order, and are not necessarily limited to the order of the steps described. The use of any examples or exemplary terms is merely for the purpose of illustrating the technical idea, and the scope of the invention is not limited by the claims, and should not be construed as being limited by said examples or exemplary terms.

[0028] In the following description, when ordinal numbers such as "first" and "second" are used, unless otherwise specified, they are used for convenience and do not stipulate any particular order.

[0029] (First embodiment) A semiconductor bonding apparatus 1 according to a first embodiment of the present invention will be described below with reference to FIGS.

[0030] Fig. 1 is a diagram showing a schematic configuration of a semiconductor bonding apparatus 1 according to this embodiment. As shown in Fig. 1, the semiconductor bonding apparatus 1 includes a bonding head 10, a driving mechanism 20, a stage 30, and a shape sensor 40. The bonding head 10, the driving mechanism 20, and the shape sensor 40 are controlled by a controller (not shown).

[0031] The bonding head 10 suction-holds the semiconductor chip CH. The bonding head 10 suction-holds the semiconductor chip CH using a holding unit 50 attached to the bottom of the head housing. More specifically, the bonding head 10 suction-holds the peripheral region of the semiconductor chip CH by applying negative pressure, while supplying positive pressure to the central region of the semiconductor chip CH to deform the semiconductor chip CH into a convex shape. The holding unit 50 is configured to be movable in the vertical direction. The detailed configuration of the bonding head 10 will be described later.

[0032] The driving mechanism 20 moves the bonding head 10 in the horizontal direction. The driving mechanism 20 includes a driving rail and a motor (not shown), and moves the bonding head 10 between a first position where the bonding head 10 is located above the stage 30 and a second position where the bonding head 10 is located above the shape sensor 40.

[0033] A substrate WA to which a semiconductor chip CH is to be bonded is placed on the stage 30. At the first position, the bonding head 10 lowers the holder 50 that is holding the semiconductor chip CH by suction, thereby bonding the semiconductor chip CH to the substrate WA. More specifically, the semiconductor chip CH, which is held by suction by the holder 50 in a convex shape, is pressed against the substrate WA, thereby bonding the semiconductor chip CH to the substrate WA. A bonding agent (not shown) is applied to the substrate WA as needed.

[0034] The shape sensor 40 is, for example, an optical interferometer, and measures the shape of the semiconductor chip CH. At the second position, the shape sensor 40 measures the convex shape of the semiconductor chip CH that is sucked and held by the bonding head 10. The measurement result of the shape sensor 40 is fed back to the bonding head 10, and the convex shape of the semiconductor chip CH is adjusted based on the measurement result.

[0035] The semiconductor bonding apparatus 1 may include components other than those described above, or may not include some of the components described above. For example, the semiconductor bonding apparatus 1 may not include the shape sensor 40.

[0036] Next, the configuration of the joining head 10 will be described in detail with reference to Figures 2 and 3. Figure 2 is a diagram showing a schematic configuration of the joining head 10. Figure 3A is a cross-sectional view showing a schematic configuration of the holding unit 50 of the joining head 10, and Figure 3B is a bottom view showing a schematic configuration of the base member of the holding unit 50.

[0037] As shown in FIG. 2, the bonding head 10 has a holder 50 that holds the semiconductor chip CH by suction, and a head main body 60 that supplies positive and negative pressure to the holder 50.

[0038] <Holding part 50> The holding portion 50 has a base member 70 connected to the lower portion of the head main body portion 60, and a porous plate-like member 80 joined to the bottom surface 70B of the base member 70.

[0039] The base member 70 is made of a non-porous ceramic material. The upper part of the base member 70 is connected to the lower part of the housing 60h of the head main body 60, and the bottom surface 70B of the base member 70 is joined to the second surface 82 of the porous plate-like member 80. As shown in FIGS. 3A and 3B, a first space 71 is formed in the central region of the base member 70 for introducing at least a positive pressure to the central region of the second surface 82 of the porous plate-like member 80. Meanwhile, a second space 72 is formed in the peripheral region of the base member 70 for introducing at least a negative pressure to a peripheral region located outside the central region of the second surface 82 of the porous plate-like member 80. The first space 71 is a circular ventilation hole. The second space 72 is a rectangular ventilation groove formed to surround the first space 71.

[0040] The porous plate-like member 80 is made of a porous ceramic material that is breathable. The porous plate-like member 80 has a second surface 82 that is bonded to the bottom surface 70B of the base member 70 and a first surface 81 that contacts the semiconductor chip CH. The porous plate-like member 80 adsorbs and holds the peripheral region of the semiconductor chip CH by applying negative pressure to the peripheral region of the second surface 82. The porous plate-like member 80 also deforms the central region of the semiconductor chip CH into a convex shape by applying positive pressure to the central region of the second surface 82. The porous plate-like member 80 has a rectangular shape that is approximately the same size as the semiconductor chip CH.

[0041] The porous ceramic material is formed by sintering particles of aluminum oxide or silicon carbide, and has air holes of about 1 μm to 10 μm. The shape and dimensions (size, thickness) of the porous plate-like member 80 and the type and size of the porous material (particles) used are changed appropriately depending on the size and thickness of the semiconductor chip CH.

[0042] The porous material constituting the porous plate-like member 80 is not limited to ceramic material, and any porous material having air permeability can be used. For example, the porous plate-like member 80 may be made of a porous glass material. The base member 70 may also be made of a metal material such as an aluminum alloy. The pore diameter of the porous material is preferably sufficiently small compared to the thickness of the semiconductor chip CH.

[0043] <Head main body 60> The head main body 60 has a negative pressure supplying part 61 for supplying negative pressure to the second space 72 of the base member 70, and a positive pressure supplying part 62 for supplying positive pressure to the first space 71 of the base member 70.

[0044] [Negative pressure supply unit 61] The negative pressure supply unit 61 includes a vacuum pump 61a, a regulator 61b, a solenoid valve 61c, and a pressure sensor 61d.

[0045] The vacuum pump 61a is connected to the second space 72 of the base member 70 via a regulator 61b and a solenoid valve 61c. The pressure sensor 61d is disposed between the solenoid valve 61c and the second space 72. The solenoid valve 61c and the pressure sensor 61d are disposed inside a housing 60h of the head main body 60, and the vacuum pump 61a and the regulator 61b are disposed outside the housing 60h.

[0046] The vacuum pump 61a supplies negative pressure to the second space 72 of the base member 70. The regulator 61b adjusts the magnitude of the negative pressure supplied to the second space 72 of the base member 70. The solenoid valve 61c switches between a first state in which the second space 72 is connected to the vacuum pump 61a and a second state in which the second space 72 is open to the atmosphere. When the second space 72 is in the first state, the semiconductor chip CH is sucked and held by the holding unit 50. On the other hand, when the second space 72 is in the second state, the semiconductor chip CH is released from the holding unit 50. The pressure sensor 61d is used to determine whether the holding unit 50 has sucked and held the semiconductor chip CH.

[0047] [Positive pressure supply unit 62] The positive pressure supply unit 62 includes a servo valve 62a, a compressor 62b, regulators 62c and 62f, pressure sensors 62d, 62g, and 62j, a vacuum pump 62e, solenoid valves 62h and 62i, and a throttle valve 62k. The servo valve 62a, the pressure sensor 62j, the throttle valve 62k, and the solenoid valve 62i are disposed inside a housing 60h of the head main body 60. The compressor 62b, the regulators 62c and 62f, the pressure sensors 62d and 62g, the vacuum pump 62e, and the solenoid valve 62h are disposed outside the housing 60h.

[0048] Servo valve 62a has a primary port connected to compressor 62b, an exhaust port connected to vacuum pump 62e, and a secondary port connected to a first space 71 in base member 70. Compressor 62b is connected to the primary port of servo valve 62a via regulator 62c, and pressure sensor 62d is located between regulator 62c and servo valve 62a. Vacuum pump 62e is connected to the exhaust port of servo valve 62a via regulator 62f and solenoid valve 62h, and pressure sensor 62g is located between regulator 62f and solenoid valve 62h. First space 71 in base member 70 is connected to the secondary port of servo valve 62a via solenoid valve 62i, and pressure sensor 62j and throttle valve 62k are located between servo valve 62a and solenoid valve 62i.

[0049] The servo valve 62a is a nozzle-flapper type servo valve and is controlled by a controller (not shown). The servo valve 62a includes two variable throttle valves and adjusts the flow rate of the positive pressure supplied from the compressor 62b and the flow rate of the negative pressure supplied from the vacuum pump 62e, thereby adjusting the magnitude of the positive pressure supplied to the first space 71 of the base member 70.

[0050] Compressor 62b serves as a positive pressure supply source and supplies positive pressure to servo valve 62a. The magnitude of the positive pressure supplied from compressor 62b to servo valve 62a is detected by pressure sensor 62d and adjusted by regulator 62c. Vacuum pump 62e serves as a negative pressure supply source and supplies negative pressure to servo valve 62a. The magnitude of the negative pressure supplied from vacuum pump 62e to servo valve 62a is detected by pressure sensor 62g and adjusted by regulator 62f. Solenoid valve 62h switches between a first state in which the exhaust port of servo valve 62a is connected to vacuum pump 62e and a second state in which the exhaust port of servo valve 62a is open to the atmosphere.

[0051] The pressure sensor 62j detects the magnitude of the positive pressure supplied from the servo valve 62a to the first space 71 of the base member 70. The output of the pressure sensor 62j is fed back to the servo valve 62a. The throttle valve 62k adjusts the flow rate of the positive pressure supplied from the servo valve 62a to the first space 71 of the base member 70. The solenoid valve 62i switches between a first state in which the first space 71 is connected to the servo valve 62a and a second state in which the first space 71 is open to the atmosphere.

[0052] The head main body 60 may include components other than those described above, or may not include some of the components described above. For example, the head main body 60 may not include the solenoid valve 62i or the pressure sensor 62j. Alternatively, the head main body 60 may include a flow rate sensor between the servo valve 62a and the solenoid valve 62i instead of the pressure sensor 62j.

[0053] Furthermore, the negative pressure supply unit 61 does not have to include the vacuum pump 61a. In this case, negative pressure is supplied to the second space 72 of the base member 70 from a negative pressure supply source such as a separate vacuum pump provided outside the semiconductor bonding apparatus 1. Similarly, the positive pressure supply unit 62 does not have to include the compressor 62b or the vacuum pump 62e. In this case, positive pressure and negative pressure are respectively supplied to the servo valve 62b from separate positive pressure supply sources and negative pressure supply sources provided outside the semiconductor bonding apparatus 1.

[0054] Furthermore, in this specification, the term "positive pressure" refers to a pressure higher than the pressure of the environment in which the semiconductor bonding apparatus 1 is installed, and the term "negative pressure" refers to a pressure lower than the pressure of the environment in which the semiconductor bonding apparatus 1 is installed. Therefore, when the semiconductor bonding apparatus 1 is installed in the atmosphere, "positive pressure" refers to a pressure higher than atmospheric pressure, and "negative pressure" refers to a pressure lower than atmospheric pressure. Furthermore, when the semiconductor bonding apparatus 1 is installed in a clean room, "positive pressure" refers to a pressure higher than the pressure in the clean room, and "negative pressure" refers to a pressure lower than the pressure in the crane room. The pressure in a clean room is generally set to a pressure slightly higher than atmospheric pressure.

[0055] Similarly, the term "open to the atmosphere" means that the pressure in the first space 71 or the second space 72 becomes the same as the pressure in the environment in which the semiconductor bonding apparatus 1 is installed. Therefore, if the semiconductor bonding apparatus 1 is installed in a clean room, "open to the atmosphere" means that the pressure in the first space 71 or the second space 72 becomes the same as the pressure in the clean room.

[0056] According to the semiconductor bonding apparatus 1 of this embodiment configured as described above, the semiconductor chip CH is sucked and held via the porous plate-like member 80. Specifically, the peripheral region of the semiconductor chip CH is sucked and held by negative pressure supplied to the peripheral region of the second surface 82 of the porous plate-like member 80. Meanwhile, the central region of the semiconductor chip CH is pressed toward the substrate WA by positive pressure supplied to the central region of the second surface 82 of the porous plate-like member 80, and the central region of the semiconductor chip CH is deformed into a convex shape.

[0057] In addition, according to the semiconductor bonding apparatus 1 of this embodiment, the magnitude of the positive pressure for forming the convex shape of the semiconductor chip CH is controlled by the servo valve 62a, so that the convex shape of the semiconductor chip CH can be controlled with precision. Specifically, the servo valve 62a precisely controls a minute pressure close to atmospheric pressure, and the semiconductor chip CH can be deformed into a desired convex shape while preventing excessive stress from being applied to the semiconductor chip CH.

[0058] In the semiconductor bonding apparatus 1 of this embodiment, for example, the measurement result of the semiconductor chip CH by the shape sensor 40 is fed back to the servo valve 62a, thereby deforming the semiconductor chip CH into a desired convex shape.

[0059] Next, the function and effect of the servo valve 62a will be described in detail with reference to FIG.

[0060] Fig. 4 is a diagram showing the relationship between the input current to the servo valve 62a and the supply pressure. The horizontal axis of Fig. 4 represents the input current to the servo valve 62a, and the vertical axis represents the pressure supplied to the first space 71 of the base member 70. In Fig. 4, three types of pressure changes are shown by solid lines, dashed lines, and dashed lines.

[0061] 4, in the semiconductor bonding apparatus 1 of this embodiment, the magnitude of the pressure supplied to the first space 71 of the base member 70 changes according to the input current of the servo valve 62a. Specifically, the larger the input current of the servo valve 62a, the greater the pressure supplied to the first space 71. The magnitude and range of change of the pressure supplied to the first space 71 change according to the magnitude and flow rate of the positive pressure supplied from the compressor 62b and the magnitude and flow rate of the negative pressure supplied from the vacuum pump 62e.

[0062] Therefore, according to the semiconductor bonding apparatus 1 of this embodiment, by controlling the positive pressure supplied to the first space 71 of the base member 70 by the servo valve 62a, it becomes possible to precisely control the pressure at around atmospheric pressure. As a result, it becomes possible to precisely control the convex shape of the semiconductor chip CH.

[0063] In the semiconductor bonding apparatus 1 of this embodiment, the servo valve 62a is configured to cut off the positive pressure when the power is cut off so that the semiconductor chip CH is not blown away even if the power is unintentionally cut off. Also, in the semiconductor bonding apparatus 1 of this embodiment, the servo valve 62a is configured to supply negative pressure to the first space 71 of the base member 70 during periods other than the period during which the semiconductor chip CH is being deformed into a convex shape.

[0064] Next, the function and effect of the throttle valve 62k will be described in detail with reference to FIG.

[0065] Fig. 5 is a diagram showing the relationship between the input current to the servo valve 62a, the supply pressure, and the throttle valve 62k. The horizontal axis of Fig. 5 represents the input current to the servo valve 62a, and the vertical axis represents the pressure supplied to the first space 71 of the base member 70. The solid line in Fig. 5 represents the relationship between the input current and the pressure when the throttle valve 62k is throttling the flow rate, and the dashed line represents the relationship between the input current and the pressure when the throttle valve 62k is not throttling the flow rate.

[0066] 5, in the semiconductor bonding apparatus 1 of this embodiment, the range of change in pressure supplied to the first space 71 of the base member 70 changes depending on whether the throttle valve 62k throttles the flow rate or not. Specifically, when the throttle valve 62k does not throttle the flow rate, the range of change in pressure is a first range ΔP0, whereas when the throttle valve 62k throttles the flow rate, the range of change in pressure is a second range ΔP1 that is narrower than the first range ΔP0.

[0067] Therefore, according to the semiconductor bonding apparatus 1 of this embodiment, by using the throttle valve 62k to throttle the flow rate of the gas flowing from the servo valve 62a toward the first space 71, it is possible to control the pressure within a narrow range of change with higher precision. As a result, it is possible to more precisely control the convex shape of the semiconductor chip CH. Note that the throttle valve 62k may be a variable throttle valve or a fixed throttle valve.

[0068] Next, the pressing operation of the holding portion 50 will be described with reference to FIGS. 6A and 6B.

[0069] Fig. 6A is a diagram showing the force applied to the surface of the semiconductor chip CH by the semiconductor bonding apparatus 1 of this embodiment, and Fig. 6B is a diagram showing, as a comparative example, the force applied to the surface of the semiconductor chip CH by a general semiconductor bonding apparatus that does not include a porous plate-like member.

[0070] 6B, in a typical semiconductor bonding apparatus, the bottom surface 75B of the base member (collet) 75 is in direct contact with the semiconductor chip CH when the semiconductor chip CH is pressed against the substrate WA. However, because the bottom surface 75B of the base member 75 has a ventilation space 75S formed therein, the typical semiconductor bonding apparatus is unable to apply a uniform force to the semiconductor chip CH. Specifically, in a typical semiconductor bonding apparatus, the force at the portion where the ventilation space 75S is formed is smaller than that at the surface that contacts the semiconductor chip CH, resulting in an uneven force being applied to the surface of the semiconductor chip CH.

[0071] 6A, in the semiconductor bonding apparatus 1 of this embodiment, the semiconductor chip CH is pressed against the substrate WA with the first surface 81 of the porous plate-like member 80 in contact with the entire semiconductor chip CH. Since the first surface 81 of the porous plate-like member 80 is substantially flat and has no portion through which force escapes, the semiconductor bonding apparatus 1 of this embodiment can apply a uniform force to the surface of the semiconductor chip CH. Therefore, the semiconductor bonding apparatus 1 of this embodiment improves the bonding quality of the semiconductor chip CH.

[0072] In a typical semiconductor bonding apparatus, the width of the groove (ventilation space 75S) on the bottom surface 75B of the base member 75 needs to be sufficiently narrow relative to the thickness of the semiconductor chip CH. Therefore, in a typical semiconductor bonding apparatus, it becomes necessary to form the narrow groove by microfabrication. On the other hand, in the semiconductor bonding apparatus 1 of this embodiment, the bottom surface 70B of the base member 70 is covered with the porous plate-like member 80, so there is no need to form a narrow groove in the base member 70, and microfabrication is not required.

[0073] Furthermore, in the semiconductor bonding apparatus 1 of this embodiment, the bottom surface 70B of the base member 70 is covered with the porous plate-like member 80, so the alignment marks of the semiconductor chips CH are not drawn into the second spaces 72 of the base member 70. Therefore, the semiconductor bonding apparatus 1 of this embodiment makes it possible to stabilize the image recognition accuracy of the alignment marks.

[0074] Next, the effects of the porous plate-like member 80 will be described with reference to FIGS.

[0075] Fig. 7A is a diagram showing the pressure gradient on the surface of the holding part 50 in the semiconductor bonding apparatus 1 of this embodiment. Fig. 7B is a diagram showing, as a comparative example, the pressure gradient on the surface of the holding part in a general semiconductor bonding apparatus that does not include a porous plate-like member.

[0076] As shown in Fig. 7B, in a typical semiconductor bonding apparatus, base member 75 directly contacts semiconductor chip CH. Therefore, the pressure gradient changes abruptly at the boundary between ventilation space 75SA, which is under negative pressure, and convex portion space 75SB, which is under positive pressure. As a result, as shown in Fig. 8, in a typical semiconductor bonding apparatus, gap SL is formed between ventilation space 75SA and semiconductor chip CH, and the flow of gas from convex portion space 75SB toward ventilation space 75SA may cause vibration of semiconductor chip CH.

[0077] 7A, in the semiconductor bonding apparatus 1 of this embodiment, the positive and negative pressures supplied from the base member 70 to the second surface 82 of the porous plate-like member 80 are averaged inside the porous plate-like member 80, so that the pressure gradient on the surface of the holding part 50 (the first surface 81 of the porous plate-like member 80) becomes gentle. As a result, the semiconductor bonding apparatus 1 of this embodiment does not cause vibration of the semiconductor chip CH due to a sudden change in pressure, and it becomes possible to stably suction and hold the semiconductor chip CH.

[0078] Fig. 9A is a diagram showing the vibration measurement results of a semiconductor chip held by suction using the semiconductor bonding apparatus 1 of this embodiment. Fig. 9B is a diagram showing the vibration measurement results of a semiconductor chip held by suction using a general semiconductor bonding apparatus that does not include a porous plate-like member. In Figs. 9A and 9B, the vibration of the semiconductor chip was actually measured using an optical interferometer.

[0079] As shown in Fig. 9B, in a typical semiconductor bonding apparatus, the vertical position (height) of the semiconductor chip fluctuates up and down over time, indicating that the semiconductor chip is vibrating. On the other hand, as shown in Fig. 9A, in the semiconductor bonding apparatus 1 of this embodiment, the position of the semiconductor chip hardly changes, indicating that the semiconductor chip is not vibrating.

[0080] As described above, the semiconductor bonding apparatus 1 of this embodiment uses the holding unit 50 composed of the base member 70 and the porous plate-like member 80, making it possible to stably hold the semiconductor chip CH by suction and to uniformly press the semiconductor chip CH against the substrate WA. Furthermore, the semiconductor bonding apparatus 1 of this embodiment adjusts the positive pressure supplied to the first space 71 of the base member 70 by the servo valve 62a, making it possible to precisely control the convex shape of the semiconductor chip CH.

[0081] When bonding a thin semiconductor chip CH, increasing the amount of convexity of the semiconductor chip CH reduces alignment accuracy and increases damage to the semiconductor chip due to horizontal stretching and stress generated in the curved portion during bonding. Therefore, the larger and thinner the semiconductor chip CH, the more accurately it is necessary to control the amount of convexity. In other words, the servo valve 62a must accurately control the pressure near atmospheric pressure.

[0082] Furthermore, as described above, in the semiconductor bonding apparatus 1 of this embodiment, the measurement result of the convex shape by the shape sensor 40 is fed back to the servo valve 62a in order to deform the semiconductor chip CH into a desired convex shape. However, unlike this embodiment, the output of the pressure sensor 62j (or a flow rate sensor) may be fed back to the servo valve 62a instead of the measurement result of the shape sensor 40.

[0083] Furthermore, a precision electropneumatic regulator may be used instead of the servo valve 62a. However, even if a precision electropneumatic regulator is used to adjust pressure to near atmospheric pressure and transmit it to the base member, pressure near atmospheric pressure will experience significant pressure loss in the air transmission path, making it impossible to accurately transmit pressure to the base member. Furthermore, precision electropneumatic regulators are large, making them difficult to place inside or near the housing 60h of the head main body 60, and they also have poor responsiveness. Therefore, the servo valve 62a is preferable to a precision electropneumatic regulator.

[0084] (Variation) In the above-described embodiment, a circular vent hole is formed in the bottom surface 70B of the base member 70 as the first space 71 for introducing at least a positive pressure into the central region of the porous plate-like member 80. In addition, a rectangular vent groove is formed as the second space 72 for introducing at least a negative pressure into the peripheral region of the porous plate-like member 80. However, the shapes of the first space 71 and the second space 72 are not limited to those in the above-described embodiment.

[0085] 10A and 10B, the second space 72 may be a ventilation groove having four rectangular recessed regions 72a-72d corresponding to the four corners of the bottom surface 70B of the base member 70 and narrow grooves 72e-72h connecting adjacent rectangular recessed regions 72a-72d. Alternatively, as shown in FIGS. 11A and 11B, the second space 72 may be composed of only the four rectangular recessed regions 72a-72d.

[0086] Note that, as long as the suction force sufficient to suction the semiconductor chip can be ensured, the second space may have a structure that allows gas to flow in from the outside. Furthermore, the first space 71 does not necessarily have to be located at the center of the bottom surface 70B of the base member 70, and for example, the first space 71 formed from a circular ventilation hole may be provided so as to be offset from the center of the bottom surface 70B.

[0087] Alternatively, for example, only ventilation holes may be formed in the base member 70, and ventilation grooves for introducing negative pressure may be formed in the second surface 82 of the porous plate-like member 80. Alternatively, for example, only ventilation holes may be formed in the base member 70, and ventilation grooves for introducing positive pressure may be formed in the second surface 82 of the porous plate-like member 80.

[0088] (Second embodiment) Next, a semiconductor bonding apparatus 1 according to a second embodiment of the present invention will be described with reference to Fig. 12. The semiconductor bonding apparatus according to the second embodiment differs from the semiconductor bonding apparatus according to the first embodiment in that a small pump is used as a positive pressure supply unit that supplies positive pressure. Note that the same components as those in the first embodiment are denoted by the same reference numerals and their description will be omitted.

[0089] 12 is a diagram showing a schematic configuration of the semiconductor bonding apparatus 1 according to this embodiment. As shown in FIG. 12, the semiconductor bonding apparatus 1 according to this embodiment includes a miniature pump 90 as a positive pressure supply unit. The miniature pump 90 is provided inside the housing 60h of the head main body 60.

[0090] The miniature pump 90 is a piezoelectric diaphragm pump. The miniature pump 90 is connected to the first space 71 of the base member 70 and supplies a positive pressure to the first space 71 of the base member 70.

[0091] According to the semiconductor bonding apparatus 1 of this embodiment configured as described above, the positive pressure for forming the convex shape of the semiconductor chip CH is controlled by the small pump 90, making it possible to control the convex shape of the semiconductor chip CH accurately and quickly.

[0092] Note that small pumps such as piezoelectric diaphragm pumps generally have a low supply pressure, so the semiconductor bonding apparatus 1 according to this embodiment is particularly effective for large and thin semiconductor chips CH. Also, small pumps such as piezoelectric diaphragm pumps generally have a low flow rate, but by placing the pump inside the housing 60h of the head main body 60, the convex shape of the semiconductor chip CH can be controlled even with a low flow rate.

[0093] The present invention is not limited to the above-described embodiments, but can be modified in various ways within the scope of the claims.

[0094] For example, in the above-described embodiment, the servo valve 62a and the miniature pump 90 are disposed inside the housing 60h of the head main body 60. However, the servo valve 62a and the miniature pump 90 may be disposed near the housing 60h.

[0095] In the above-described embodiment, an optical interferometer is used as the shape sensor 40. However, the shape sensor 40 may be a line sensor or an image sensor that can capture an image of the semiconductor chip CH from the side and measure the convex shape. [Explanation of symbols]

[0096] 1. Semiconductor bonding equipment, 10 joining head, 20 drive mechanism, 30 stages, 40 shape sensors, 50 holding part, 60 head main body, 60h case, 61a, 62e vacuum pump, 62a Servo valve, 62b compressor, 62k throttle valve, 70 base member, 71 1st space, 72 Second space, 80 porous plate-like member, 81 Page 1, 82 2nd page, 90 small pumps, CH semiconductor chip, WA board.

Claims

1. a porous plate-like member made of a porous material having air permeability, the porous plate-like member having a first surface that contacts the semiconductor chip and a second surface opposite to the first surface; a base member joined to the second surface of the porous plate member, the base member having a first space for introducing at least a positive pressure into a central region of the second surface of the porous plate member and a second space for introducing at least a negative pressure into a peripheral region located outside the central region of the second surface of the porous plate member; a negative pressure supply unit that supplies a negative pressure to the second space of the base member to cause the porous plate-like member to suction-hold the semiconductor chip; a positive pressure supply unit that supplies a positive pressure to the first space of the base member to deform the semiconductor chip that is sucked and held by the porous plate-like member into a convex shape; A semiconductor bonding device having:

2. The positive pressure supply unit is 2. The semiconductor bonding apparatus according to claim 1, further comprising a servo valve that adjusts at least the positive pressure supplied to the first space of the base member by combining the positive pressure supplied from a positive pressure supply source and the negative pressure supplied from a negative pressure supply source.

3. the base member is attached to a lower part of a housing of the joining head, The semiconductor bonding apparatus according to claim 2 , wherein the servo valve is disposed inside or near a housing of the bonding head.

4. 4. The semiconductor bonding apparatus according to claim 2, further comprising a throttle valve disposed between the servo valve and the first space.

5. a pressure sensor disposed between the servo valve and the first space; 4. The semiconductor bonding apparatus according to claim 2, wherein an output of said pressure sensor is fed back to said servo valve.

6. a flow rate sensor disposed between the servo valve and the first space; 4. The semiconductor bonding apparatus according to claim 2, wherein an output of said flow rate sensor is fed back to said servo valve.

7. 4. The semiconductor bonding apparatus according to claim 2, further comprising an electromagnetic valve disposed between the servo valve and the first space, for switching between a first state in which the first space is connected to the servo valve and a second state in which the first space is open to the atmosphere.

8. a first regulator that adjusts the positive pressure supplied from the positive pressure supply source; 4. The semiconductor bonding apparatus according to claim 2, further comprising: a second regulator that adjusts the negative pressure supplied from the negative pressure supply source.

9. 4. The semiconductor bonding apparatus according to claim 2, wherein the servo valve is configured to supply a negative pressure to the first space during a period other than a period during which the semiconductor chip is being deformed into a convex shape.

10. The semiconductor bonding apparatus according to claim 1 , wherein the positive pressure supply unit includes a pump that supplies a positive pressure to the first space of the base member.

11. the base member is attached to a lower part of a housing of the joining head, The semiconductor bonding apparatus of claim 10 , wherein the pump is located within or near the housing of the bond head.

12. further comprising a shape sensor for measuring the shape of the semiconductor chip; 3. The semiconductor bonding apparatus according to claim 1, wherein the measurement result of said shape sensor is fed back to said positive pressure supply unit.

13. 3. The semiconductor bonding device according to claim 1, wherein the pore diameter of the porous material is smaller than the thickness of the semiconductor chip.

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