Bonding device

Abstract

This bonding device is provided with: a bonding tool which has a holding surface and a rear surface opposite to the holding surface and which is configured to hold a semiconductor die to the holding surface; a heater which is in contact with the rear surface so as to be able to conduct heat to the bonding tool; a body to which the heater is attached at an end portion, and in which cooling gas flow paths which supply cooling air to the heater are formed; and gas discharge members, which are attached to the body, into which the cooling air flows from discharge ports of the cooling gas flow path, and in which openings opened to outer edges of the bonding tool are provided.

Description

Bonding apparatus

[0007] ,

[0006] , ,

[0001] The present invention relates to a bonding apparatus.

[0002] When mounting a flip chip on a resin substrate via a thermosetting resin, a bonding apparatus having a function of air-purging outgas, which is a volatile component generated from the heated thermosetting resin, is known.

[0003] Japanese Patent No. 6038783

[0004] The bonding apparatus described in Patent Document 1 includes a cover that covers a bonding head, a heat tool, and an attachment. The cover is provided so as to have a gap with the attachment. The bonding apparatus fills the inside of the cover with purified air by a pressure pump, thereby making the inside of the cover in a positive pressure state. Then, air leaks out of the cover through the gap between the cover and the attachment. The bonding apparatus air-purges the outgas floating around the attachment by the leaked air. Thereby, the bonding apparatus can suppress the attachment of outgas to the bonding head, the attachment, the heat tool, and the like.

[0005] However, in the mounting apparatus described in Patent Document 1, excessive equipment such as using a pressure pump for air-purging is required, resulting in a problem that the equipment cost increases.

[0006] Therefore, the present invention has been made to solve such problems, and an object thereof is to suppress the attachment of resin outgas to a bonding tool with a simple configuration.

[0007] A bonding apparatus according to one aspect of the present invention comprises: a bonding tool having a holding surface and a back surface opposite to the holding surface, which adsorbs a semiconductor die onto the holding surface; a heater in contact with the back surface so as to be able to conduct heat to the bonding tool; a main body to which the heater is attached and which has a cooling gas passage formed therein for supplying cooling air to the heater; and a gas discharge member attached to the main body, which allows the cooling air to flow in from the outlet of the cooling gas passage and which has an opening that opens to the outer edge of the bonding tool.

[0008] The present invention makes it possible to suppress the adhesion of volatile components of resin to the bonding apparatus with a simple configuration.

[0009] This figure shows an example of the configuration of a bonding apparatus. This is a plan view showing an example of the air passage member viewed from the -Y direction. This is a plan view showing another example of the air passage member viewed from the -Y direction. This is a plan view showing another example of the air passage member viewed from the -Y direction. This is a plan view showing another example of the air passage member viewed from the -Y direction. This figure shows the bottom member of the first modified example. This figure shows the bottom member of the second modified example. This figure shows the bottom member of the third modified example. This is a flowchart showing the operation of the bonding apparatus. This figure shows how outgassing occurs when gas is drawn in from the gas suction opening.

[0010] ===Configuration of Bonding Apparatus 1=== The bonding apparatus 1 will be described with reference to Figure 1. Figure 1 is a diagram showing an example of the configuration of the bonding apparatus 1.

[0011] Bonding apparatus 1 is a device for mounting semiconductor dies onto substrates or lead frames by so-called flip-chip bonding or die bonding. Bonding apparatus 1 includes, for example, a bonding head 100 equipped with a bonding tool 110 for pressing a semiconductor die 1000 onto a substrate 1100, a substrate stage 1200 for holding the substrate 1100, and a drive unit (not shown) for driving the bonding head 100 relative to the substrate stage 1200. The bonding head 100 is configured to be movable in the X, Y, and Z axis directions. The substrate stage 1200 may be configured to be movable in the X, Y axis direction and the θ axis direction.

[0012] The bonding head 100 is equipped with a mechanism for recovering outgassing, which is a volatile component of the thermosetting resin generated when the semiconductor die 1000 is flip-chip bonded. This eliminates bonding defects and the occurrence of defective products caused by the thermosetting resin adhering to the bonding tool 110 remelting due to heat and falling onto the substrate, chip, or stage. Furthermore, this configuration reduces the frequency of maintenance required to remove the thermosetting resin accumulated on the bonding tool 110.

[0013] As shown in Figure 1, the bonding head 100 includes a bonding tool 110, a heater 120, a main body 130, and a gas discharge member 140.

[0014] The bonding tool 110 is a component for vacuum-suctioning a semiconductor die 1000 and bonding it to a predetermined position. The bonding tool 110 comprises a back surface 111 and a holding surface 112. The back surface 111 of the bonding tool 110 is machined to be flat. The holding surface 112 of the bonding tool 110 has a convex island formed to match the size of the semiconductor die 1000. Holes are provided in the island for vacuum-suctioning the semiconductor die 1000.

[0015] The heater 120 is a component for heating the semiconductor die 1000 that is vacuum-adsorbed to the bonding tool 110. The heater 120 has an upper surface 121 and a lower surface 122. The lower surface 122 of the heater 120 is in contact with the back surface 111 of the bonding tool 110 so that heat can be conducted to the bonding tool 110. The heater 120 is provided with a suction hole 124 that penetrates from the upper surface 121 to the lower surface 122. The suction hole 124 is provided so as to communicate with the hole in the island. The heater 120 heats the bonding tool 110 to about 250 degrees when bonding the semiconductor die 1000 to the electrode. Hereinafter, the surface provided in a direction intersecting the upper surface 121 of the heater 120 will be referred to as the outer edge 123.

[0016] The main body 130 is a component that can insulate the heat from the heater 120 between the bonding tool 110 and a different component. The lower surface 134 of the main body 130 is fixed in close contact with the upper surface 121 of the heater 120 by a metal fitting or the like. The main body 130 is provided with, for example, a suction path 131, a cooling gas path 132, and an air outlet 133. Hereinafter, the surface provided in a direction intersecting the lower surface 134 of the main body 130 will be referred to as the side surface 135.

[0017] The suction path 131 is a path for vacuum-suctioning the semiconductor die 1000. The suction path 131 is provided to communicate with the suction hole 124 of the heater 120. The suction path 131 is connected to the suction tube Tb and then to the suction pump P via a switching valve (not shown).

[0018] The cooling gas passage 132 is a path through which cooling air is conducted to cool the heater 120. The cooling gas passage 132 may have a contact area 132a to ensure a contact area between the heater 120 and the cooling air. The contact area 132a is, for example, a region that extends over a part of the lower surface 134 of the main body 130. The cooling gas passage 132 has a guide passage 132b from the contact area 132a to the air outlet 133.

[0019] The air outlet 133 is a hole at the end of the guide passage 132b. The air outlet 133 discharges the cooling air that has passed through the cooling gas passage 132 and cooled the heater 120.

[0020] In the above description, the contact area 132a was described as being provided on the lower surface 134 of the main body 130, but it is not limited to this. The contact area 132a may be provided, for example, on the upper surface 121 of the heater 120. In this case, the air outlet 133 is provided, for example, on the outer edge 123 of the heater 120. Alternatively, the contact area 132a may be provided on both the upper surface 121 of the heater 120 and the lower surface 134 of the main body 130. In this case, the air outlet 133 is provided, for example, at the end of the area where the heater 120 and the main body 130 are in contact.

[0021] The gas discharge member 140 is a member that allows the cooling air discharged from the air outlet 133 to pass through. The gas discharge member 140 is positioned along the outer edges of the heater 120 and the bonding tool 110. That is, the gas discharge member 140 is positioned near the outer edge 123 of the heater and the side surface 135 of the main body 130. The gas discharge member 140 is positioned so as to be able to guide the cooling air discharged from at least one of the outer edge 123 of the heater 120 or the side surface 135 of the main body 130 to the gas guide passage 144, which will be described later. Furthermore, the gas discharge member 140 is positioned so as to be able to guide outgassing to the gas guide passage 144 using the negative pressure generated by the cooling air flowing through the gas guide passage 144, which will be described later. The structure of the gas discharge member 140 will be described below.

[0022] <<Gas Discharge Member 140>> The configuration of the gas discharge member 140 will be described with reference to Figures 1 to 4. Figure 2 is a plan view showing an example of the air passage member viewed from the -Y direction side. Figure 3A is a plan view showing another example of the air passage member viewed from the -Y direction side. Figure 3B is a plan view showing another example of the air passage member viewed from the -Y direction side. Figure 4 is a plan view showing another example of the air passage member viewed from the -Y direction side.

[0023] As shown in Figure 1, the gas discharge member 140 includes at least an upper member 141 and a lower member 142. The gas discharge member 140 is formed of, for example, a metallic material (such as copper or stainless steel).

[0024] The upper member 141 is a member to which at least a portion of its end is connected to the side surface 135 of the main body 130 on the upper side (+Y direction side) of the air outlet 133. The upper member 141 is positioned so as to be inclined at an acute angle with respect to the side surface 135 toward the +Y direction, for example. The upper member 141 is attached to a flange 145 provided on the bonding head 100, for example. That is, the upper member 141 moves together with the bonding head 100.

[0025] The lower member 142 is a member provided facing the upper member 141 on the -Y direction side. The lower member 142 is positioned to form a gas suction opening 143 between itself and the outer edge 123 of the heater 120 on the lower side (-Y direction side) of the air outlet 133. The lower member 142 is positioned, for example, to be inclined on the +Y direction side. The lower member 142 is positioned, for example, parallel to the upper member 141. The lower member 142 is attached, for example, to a flange 145 provided on the bonding head 100, together with the upper member 141. That is, the lower member 142 moves together with the bonding head 100.

[0026] The gas discharge member 140 forms a gas guide passage 144 in the upper member 141 and the lower member 142 that discharges cooling air discharged from the heater 120 or the main body 130 together with outgassing generated from the bonding tool 110 side. The gas discharge member 140 generates negative pressure at the gas suction opening 143 by the flow of cooling air discharged from the air outlet 133. The gas discharge member 140 draws outgassing of thermosetting resin generated during the bonding process from the gas suction opening 143 into the gas guide passage 144 of the gas discharge member 140 (the space between the upper member 141 and the lower member 142).

[0027] Here, it is desirable that the gas discharge member 140 is arranged such that, for example, the end T10 of the upper member 141 surrounds the side surface 135 of the main body 130, and the lower member 142 is arranged parallel to the upper member 141.

[0028] In this case, as shown in Figure 2, the lower member 142 is provided with a gas suction opening 143 (opening) at a position that overlaps, in a plan view from the Y direction, with the exhaust path R1 of the cooling air discharged from the air outlet 133 (the dashed line path in Figure 2). That is, the lower member 142 has a gas suction opening 143 formed at the position where the negative pressure is greatest. As a result, the bonding head 100 can efficiently suction outgassed air from the gas suction opening 143, and it is possible to prevent outgassed thermosetting resin from adhering to members located on the +Y direction side of the heater 120.

[0029] Furthermore, as shown in Figure 3A, the lower member 142 is provided opposite the upper member 141, for example, so that the gas suction opening 143 is provided around the outer edge 123 of the heater 120 (in Figure 3A, the heater 120 and the bonding tool 110 are the same size when viewed from the Y direction, so the heater 120 is not shown). This makes it possible for the bonding head 100 to prevent outgassing of the thermosetting resin from adhering to members positioned on the +Y direction side of the heater 120.

[0030] Furthermore, as shown in Figure 3B, the lower member 142 is formed such that, for example, the gas suction opening 143a, which includes a region that overlaps with the cooling air discharge path R1 discharged from the air outlet 133 in a plan view from the Y direction, is wider than the gas suction opening 143b, which does not include the overlapping region in a plan view. As a result, the bonding head 100 can increase the suction efficiency of outgassing of the thermosetting resin, and thus more reliably prevent outgassing of the thermosetting resin from adhering to members positioned on the +Y direction side of the heater 120.

[0031] Furthermore, as shown in Figure 4, the lower member 142 does not need to be provided around the entire circumference of the outer edge 123 of the heater 120. The lower member 142 only needs to be provided such that the discharge path R1 for the cooling air discharged from the air outlet 133 and the gas suction opening 143 overlap in a plan view from the Y direction. The lower member 142 only needs to have the gas suction opening 143 located at a position where negative pressure is generated by the cooling air discharged from the air outlet 133. In this case, the gas discharge member 140 has a rectangular shape, for example, with sides and an opening (an opening for discharging cooling air) at the end opposite to the end that contacts the main body 130. As a result, the bonding head 100 can suction outgassing of the thermosetting resin with fewer members, making it possible to prevent outgassing of the thermosetting resin from adhering to members located on the +Y direction side of the heater 120.

[0032] Next, a modified example of the lower member 142 will be described with reference to Figures 5 to 7. Figure 5 shows the lower member 142 of the first modified example. Figure 6 shows the lower member 142 of the second modified example. Figure 7 shows the lower member 142 of the third modified example.

[0033] The lower member 142 may have a trap section on the surface facing the upper member 141. The trap section is a part that traps the solidified outgassed thermosetting resin, which is sucked in from the gas suction opening 143 by negative pressure, to prevent it from falling from the gas suction opening 143 onto the semiconductor substrate 1100. The trap section will be described below.

[0034] As shown in Figure 5, the trap portion 142a may be, for example, a portion provided near the gas suction opening 143 of the lower member 142 and formed to protrude toward the upper member 141. This allows the gas discharge member 140 to trap solidified outgassed material from the thermosetting resin inside, preventing it from falling from the gas suction opening 143 onto the semiconductor substrate 1100.

[0035] Furthermore, as shown in Figure 6, the trap portion 142b is provided, for example, near the gas suction opening 143 of the lower member 142 and is formed to be recessed in the surface facing the upper member 141. This makes it possible for the gas discharge member 140 to trap the solidified outgassed thermosetting resin that is sucked in from the gas suction opening 143 by negative pressure, preventing it from falling from the gas suction opening 143 onto the semiconductor substrate 1100.

[0036] Furthermore, as shown in Figure 7, the trap portion 142c is provided, for example, near the gas suction opening 143 of the lower surface member 142 and is formed in a wavy manner on the surface facing the upper surface member 141. This makes it possible for the gas discharge member 140 to trap the solidified outgassed thermosetting resin that is sucked in from the gas suction opening 143 by negative pressure, preventing it from falling from the gas suction opening 143 onto the semiconductor substrate 1100.

[0037] ===Operation of Bonding Apparatus 1=== Referring to Figure 8, the operation of the bonding apparatus 1 in which the bonding head 100 mounts the semiconductor die 1000 onto the substrate 1100 will be described. Figure 8 is a flowchart showing the operation of the bonding apparatus 1. Figure 9 shows how outgassing is sucked in from the gas suction opening 143.

[0038] In step S100, the substrate 1100 is held by adsorption on the substrate stage 1200.

[0039] In step S101, the bonding apparatus 1 holds the upper surface of the semiconductor die 1000 by adsorption to the island of the bonding tool 110.

[0040] In step S102, the bonding apparatus 1 aligns the semiconductor die 1000 and the substrate 1100 using image recognition.

[0041] In step S103, the bonding apparatus 1 heats the semiconductor die 1000 via the bonding tool 110 using the heater 120.

[0042] In step S104, the bonding apparatus 1 lowers the bonding tool 110 to press the semiconductor die 1000 against the substrate 1100.

[0043] At this time, since the semiconductor die 1000 is being heated by the heater 120, the thermosetting resin applied to the substrate 1100 is heated. When the thermosetting resin is heated, as shown in FIG. 9, outgas, which is a volatile component of the thermosetting resin, diverges around the semiconductor die 1000.

[0044] In step S105, when a predetermined time has elapsed after the bonding apparatus 1 presses the semiconductor die 1000 against the substrate 1100, the heating by the heater 120 is stopped, and cooling air is introduced from a pump (not shown) into the cooling gas flow path 132. Note that the cooling air may be introduced into the cooling gas flow path 132 while heating by the heater 120. Thereby, the outgas generated during the heating by the heater 120 can be sucked.

[0045] At this time, the cooling air that cools the bonding tool 110 is discharged from the air discharge port 133 toward the inside of the gas discharge member 140 (the space between the upper surface member 141 and the lower surface member 142). Thereby, a negative pressure is generated at the gas suction opening 143.

[0046] In step S106, as shown in FIG. 9, the bonding apparatus 1 sucks the outgas, which is the volatile component of the thermosetting resin that has diverged, from the gas suction opening 143 into the gas conduction path 144 of the gas discharge member 140. The outgas, which is the sucked volatile component, adheres, for example, in the gas conduction path 144 (the “solid component” in FIG. 9).

[0047] In this way, the bonding apparatus 1 uses the cooling air in the process of cooling the bonding tool 110 heated by the heater 120 to absorb the outgas of the thermosetting resin so that the outgas of the thermosetting resin does not adhere to the bonding head 100. That is, the bonding apparatus 1 can absorb the outgas of the thermosetting resin with a simple configuration without newly providing a pump or the like for absorbing the outgas of the thermosetting resin.

[0048] As a result, even if the operating time of the bonding apparatus 1 increases, the bonding apparatus 1 can prevent the adhesion of outgases of the thermosetting resin to each member constituting the bonding head 100. Further, in the bonding apparatus 1, it is possible to prevent the condensation and solidification of outgases of the thermosetting resin in the gap between the heater 120 and the bonding tool 110, the holes of the island, and the like.

[0049] ===Summary=== <1> The bonding apparatus 1 includes a bonding tool 110 having a holding surface 112 and a back surface 111 opposite to the holding surface 112, and adsorbing a semiconductor die 1000 on the holding surface 112, a heater 120 contacting the back surface 111 so as to be thermally conductive to the bonding tool 110, a main body 130 to which the heater 120 is attached at an end portion and in which a cooling gas flow path 132 for supplying cooling air to the heater 120 is formed, and a gas discharge member 140 attached to the main body 130, into which cooling air flows from an air discharge port 133 (discharge port) of the cooling gas flow path 132, and provided with a gas suction opening 143 (opening) opening to the outer edge of the bonding tool 110. Thereby, the bonding apparatus 1 can suppress the adhesion of outgases, which are volatile components of the resin, to the bonding apparatus 1 with a simple configuration.

[0050] <2> In the bonding apparatus 1, the gas discharge member 140 has an upper surface member 141 and a lower surface member 142 facing the upper surface member 141, and the gas suction opening 143 (opening) is formed in the lower surface member 142. The bonding apparatus according to <1>. Thereby, the bonding apparatus 1 can suppress the adhesion of outgases, which are volatile components of the resin, to the bonding apparatus 1 with a simple configuration.

[0051] <3> In the bonding apparatus 1, the lower surface member 142 is provided so as to form the gas suction opening 143 (opening) over the entire circumference of the outer edge 123 of the heater 120. The bonding apparatus according to <1> or <2>. Thereby, the bonding apparatus 1 can more reliably suppress the adhesion of outgases, which are volatile components of the resin, to the bonding apparatus 1 with a simple configuration.

[0052] <4> The bonding apparatus 1 according to <2> or <3>, wherein the end of the upper member 141 is connected to the main body 130 such that it forms an acute angle with the side surface 135 of the main body 130, and the lower member 142 is provided substantially parallel to the upper member 141 and has trap portions 142a to 142c on the surface facing the upper member 141.

[0053] <5> The bonding apparatus 1 according to any one of <2> to <4>, wherein the trap portion 142a is formed on the surface facing the upper surface member 141 so as to protrude toward the upper surface member 141. As a result, the bonding apparatus 1 can more reliably suppress the adhesion of outgassing, which is a volatile component of the resin, to the bonding apparatus 1 with a simple configuration.

[0054] <6> The bonding apparatus according to any one of <2> to <4>, wherein the trap portion 142b is formed to be recessed in the surface facing the upper surface member 141. As a result, the bonding apparatus 1 can more reliably suppress the adhesion of outgassing, which is a volatile component of the resin, to the bonding apparatus 1 with a simple configuration.

[0055] <7> The bonding apparatus 1 according to any one of <2> to <4>, wherein the trap portion 142c is formed so that the surface facing the upper surface member 141 is wavy. As a result, the bonding apparatus 1 can more reliably suppress the adhesion of outgassing, which is a volatile component of the resin, to the bonding apparatus 1 with a simple configuration.

[0056] <8> The bonding apparatus 1 according to any one of <2> to <7>, wherein the upper member 141 is connected to the side surface 135 of the main body 130 such that its end surrounds the side surface 135 of the main body 130 all the way around.

[0057] <9> The bonding apparatus 1 according to any one of <2> to <7>, wherein the upper member 141 and the lower member 142 are made of a metal material. As a result, the bonding apparatus 1 can suppress the adhesion of outgassing, which is a volatile component of the resin, to the bonding apparatus 1 with a simple configuration and ensure durability. <10> The bonding head 100 has a holding surface 112 and a back surface 111 opposite to the holding surface 112, and includes a bonding tool 110 that adsorbs a semiconductor die 1000 onto the holding surface 112, a heater 120 that contacts the back surface 111 so as to be able to conduct heat to the bonding tool 110, a main body 130 to which the heater 120 is attached and which has a cooling gas passage 132 formed therein for supplying cooling air to the heater 120, and a gas discharge member 140 attached to the main body 130 into which cooling air flows from an air outlet 133 (outlet) of the cooling gas passage 132 and which has a gas suction opening 143 (opening) that opens to the outer edge of the bonding tool 110. As a result, the bonding head 100 can suppress the adhesion of outgassing, which is a volatile component of the resin, to the bonding head 100 with a simple configuration.

[0058] The embodiments described above can be combined, modified, or improved as appropriate depending on the application, and the present invention is not limited to the embodiments described above. It is clear from the claims that such combinations or modified or improved forms may also fall within the technical scope of the present invention.

[0059] 1...Bonding device, 100...Bonding head, 110...Bonding tool, 120...Heater, 123...Outer edge, 130...Main body, 132...Cooling gas passage, 135...Side, 140...Gas discharge member, 141...Upper member, 142...Lower member, 143...Gas suction opening, 144...Gas guide passage.

Claims

1. A bonding apparatus comprising: a bonding tool having a holding surface and a back surface opposite to the holding surface, the bonding tool adsorbing a semiconductor die onto the holding surface; a heater in contact with the back surface so as to be able to conduct heat to the bonding tool; a main body to which the heater is attached and which has a cooling gas passage formed therein for supplying cooling air to the heater; and a gas discharge member attached to the main body, to which the cooling air flows in from the outlet of the cooling gas passage and which has an opening that opens to the outer edge of the bonding tool.

2. The bonding apparatus according to claim 1, wherein the gas discharge member has an upper member and a lower member facing the upper member, and the opening is formed in the lower member.

3. The bonding apparatus according to claim 2, wherein the lower surface member is provided to form the opening around the entire circumference of the outer edge of the heater.

4. The bonding apparatus according to claim 2, wherein the end of the upper member is connected to the main body such that it forms an acute angle with the side surface of the main body, and the lower member is provided substantially parallel to the upper member and has a trap portion on the surface facing the upper member.

5. The bonding apparatus according to claim 4, wherein the trap portion is formed on the surface facing the upper surface member so as to protrude toward the upper surface member.

6. The bonding apparatus according to claim 4, wherein the trap portion is formed to be recessed in the surface facing the upper member.

7. The bonding apparatus according to claim 4, wherein the trap portion is formed such that the surface facing the upper surface member is wavy.

8. The bonding apparatus according to any one of claims 2 to 7, wherein the upper member is connected to the side surface of the main body such that its end surrounds the side surface of the main body.

9. The bonding apparatus according to any one of claims 2 to 7, wherein the upper member and the lower member are formed of a metal material.

10. A bonding head comprising: a bonding tool having a holding surface and a back surface opposite to the holding surface, the bonding tool adsorbing a semiconductor die onto the holding surface; a heater in contact with the back surface so as to be able to conduct heat to the bonding tool; a main body to which the heater is attached and which has a cooling gas passage formed therein for supplying cooling air to the heater; and a gas discharge member attached to the main body, which allows the cooling air to flow in from the outlet of the cooling gas passage and has an opening that opens to the outer edge of the bonding tool.

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