Die bonding apparatus having independent pressing module

Abstract

The present invention relates to a die bonding apparatus that bonds a plurality of dies on a substrate, wherein an upper chamber comprises: an upper frame (110, 120) having an open lower surface, a first upper surface, and a first side surface; and pressing modules (130) that are coupled to the first upper surface and apply a predetermined pressure from above to the dies located in a bonding space. A lower chamber comprises: a lower frame (210, 220) having an open upper surface, a second lower surface, and a second side surface; and a support (230) supporting the substrate located in the bonding space. The pressing module (M) includes a plurality of pressing blocks (150) which are arranged to pass through the first upper surface of the upper frame and contact the upper surfaces of the dies and apply pressure thereto. The plurality of pressing blocks include elastic bodies having different elastic moduli and apply different pressures to the dies.

Description

Die bonding device equipped with an independent pressure module

[0001] The present invention relates to a die bonding apparatus for bonding a plurality of dies onto a substrate in a semiconductor device manufacturing process, and specifically, to a die bonding manufacturing apparatus applicable to a plurality of dies having different sizes and heights disposed on a substrate, and applicable even when the substrate is tilted at a certain angle.

[0002] The packaging process, a back-end semiconductor process, proceeds in the order of back grinding, dicing, and die bonding; in the semiconductor process, bonding refers to 'adhering' a wafer chip to a substrate.

[0003] Dies (chips separated from the wafer) diced from the wafer are picked up by a plunger, placed on the surface of a package substrate, and bonded through a bonding process. When bonding dies, they are connected using alloys such as gold or silver, solder or metal-containing paste, or polymers. Among polymer materials, silver-containing paste or liquid epoxy is primarily used. This bonding process must be designed to ensure that the chip maintains a stable electrical connection and that heat transfer is achieved effectively.

[0004] As such, die bonding is a process of sintering a die by applying heat and pressure while the die is placed on a substrate. To apply a constant force to the die on the substrate, it is generally necessary to provide a pressurizing device positioned above the die to apply pressure. Conventional pressurizing devices of this type have a structure that applies a constant force uniformly to the entire die, which has the following problems.

[0005] Dies bonded to a substrate can each have different heights and widths. When the same pressure is applied to multiple dies of varying sizes and heights, the pressure required for each semiconductor chip is not properly supplied. As a result, the overall bonding quality is affected, which may lead to a shortened lifespan or failure.

[0006] Furthermore, in conventional die bonding devices, specific parts, such as those located on the outer side of the substrate beneath the die, may not receive the necessary pressure during bonding. Additionally, if the substrate is not perfectly horizontal and is slightly tilted, the pressure device applying pressure to the die moves only in the vertical direction; consequently, this results in uneven pressure application to the die on the tilted substrate, which also leads to issues with product quality.

[0007] The present invention aims to provide a technology that can appropriately apply the necessary pressure even when the size and height of the dies differ during the process of sintering and bonding a die onto a substrate, and can apply a force perpendicular to the upper surface of the die even when the substrate is tilted.

[0008] The present invention relates to a device for bonding a plurality of dies onto a substrate, wherein an upper chamber and a lower chamber are in contact with each other to form a bonding space in which the substrate and the dies are bonded. The upper chamber comprises an upper frame (110, 120) having a lower surface open and a first upper surface and a first side surface; and a pressure module (130) coupled to the first upper surface and applying a predetermined pressure from the upper side to a die located in the bonding space. The lower chamber comprises a lower frame (210, 220) having a upper surface open and a second lower surface and a second side surface; and a support body (230) supporting a substrate located in the bonding space.

[0009] The above-described pressure module (130) includes a plurality of pressure blocks (150) that are positioned through the first upper surface of the upper frame and apply pressure to the upper surface of the die, and the plurality of pressure blocks are characterized by having elastic bodies having different elastic moduli to apply different pressures to the die.

[0010] The above pressure block (150) is composed of a first member (152) attached to the pressure module, a second member (153) in contact with the upper surface of the die, and an elastic connecting member (154) connecting the first member and the second member, and the elastic connecting member has a predetermined elastic modulus.

[0011] When the lower surface of the second member of the pressure block presses the upper surface of the die, the upper surface of the first member (152) of the pressure block and the lower surface of the second member (153) can tilt at a certain angle to each other, thereby providing uniform surface pressure to the die even in a microscopic tilted state of the die.

[0012] The upper chamber includes a plurality of pressure modules (130), and the plurality of pressure modules are configured to operate independently of each other in response to the macroscopic inclination of the substrate.

[0013] The above-mentioned pressure module (130) includes a base member (135) to which an air cylinder that generates pressure applied to the pressure block and a load cell that measures pressure applied to the die are combined. Additionally, the above-mentioned pressure module (130) may further include a detachable member (140) to which a plurality of first members of the pressure block are connected from below and which is detachably connected to the lower surface of the base member, and the structure is such that a plurality of pressure blocks are replaced as the detachable member of the pressure module is replaced.

[0014] With the substrate and die entered into the bonding space, the upper chamber is fixed at a specific position, and the lower chamber moves toward the upper chamber to seal the bonding space.

[0015] The above lower chamber further includes a vacuum pump (300) that exhausts gas inside the bonding space to the outside, thereby making the bonding space a vacuum and enabling the use of copper in the die bonding process.

[0016] The present invention provides the advantageous effect of being able to apply the necessary pressure to each die even when the dies bonded on the substrate each have different sizes and heights, and to apply pressure uniformly in a direction perpendicular to the upper surface of the die even when the substrate is tilted.

[0017] FIG. 1 is an overall conceptual diagram of a die bonding device equipped with an independent pressure module according to the present invention, and

[0018] FIGS. 2 and 3 are exemplary views of some configurations of a die bonding device equipped with an independent pressure module according to the present invention, and

[0019] Figure 4 shows a die bonding device equipped with an independent pressure module according to the present invention operating with the substrate tilted.

[0020] FIGS. 5 to 11 are drawings sequentially showing the process of performing a die bonding process using a die bonding device equipped with an independent pressure module according to the present invention.

[0021] The objects, specific advantages, and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments in conjunction with the accompanying drawings. Additionally, the terms used are defined with respect to their functions in the present invention, which may vary according to the user's intent or practice. Therefore, the definitions of these terms should be based on the content throughout this specification.

[0022] In addition, when describing the components of the present invention, different reference numerals may be assigned to components with the same name depending on the drawing, and the same reference numeral may be assigned even if they are different drawings. However, even in such cases, this does not mean that the components have different functions depending on the embodiment, or that they have the same function in different embodiments, and the function of each component should be determined based on the description of each component in the corresponding embodiment.

[0023] Furthermore, technical terms used in this specification shall be interpreted in the sense generally understood by those skilled in the art to which the present invention pertains, unless specifically defined otherwise in this specification, and shall not be interpreted in an overly broad or overly narrow sense. Additionally, singular expressions used in this specification include plural expressions unless the context otherwise indicates.

[0024] FIG. 1 is an overall conceptual diagram of a die bonding device equipped with an independent pressure module according to the present invention, FIG. 2 and FIG. 3 are exemplary views of some configurations of a die bonding device equipped with an independent pressure module according to the present invention, and FIG. 4 shows a die bonding device equipped with an independent pressure module according to the present invention operating with the substrate tilted. FIG. 5 to FIG. 11 are drawings sequentially showing the process of performing a die bonding process using a die bonding device equipped with an independent pressure module according to the present invention.

[0025] The present invention will be described in detail below with reference to the attached drawings.

[0026] Referring to FIG. 1, a die bonding device equipped with an independent pressure module of the present invention (hereinafter referred to as the "die bonding device") is provided with an upper chamber and a lower chamber that are movable and in contact with each other to form a bonding space (S, bonding space). When the upper chamber and the lower chamber come into contact with each other, the bonding space where the substrate and the die are located is sealed from the outside by an O-ring provided between them, thereby creating a high temperature and high pressure environment for the bonding process. In FIG. 1, number 20 represents a substrate, and number 40 represents a plurality of dies placed horizontally and vertically on the substrate, and a tray (10) is provided to accommodate, support, and move these dies (40) and the substrate (20).

[0027] The upper chamber is an upper frame structure having an open bottom surface and a side surface and an upper surface. For convenience, to distinguish it from the lower chamber, the upper surface is referred to as the first upper surface (110) and the side surface as the first side surface (120). Additionally, a pressure module (130) is disposed on the first upper surface (110) of the upper chamber to apply a predetermined pressure from the upper side to a die located in the bonding space. A cooling line for cooling the bonding space is also provided on the first side surface.

[0028] Furthermore, the lower frame forming the lower chamber has a structure in which the upper surface is open and has a second lower surface (210) and a second side surface (220). Additionally, a support body (230) for supporting a substrate located in a bonding space is provided inside the lower chamber. A heater (232) for applying heat to the bonding space is disposed on the support body (230), and a feed-through (240), etc. for supplying power to the interior is also provided in the lower chamber.

[0029] Additionally, a number of pressure modules (130) are arranged in the upper chamber as needed. A pressure module is a module that applies pressure required for the bonding process to the upper surface of a die (40) on a substrate (20) supported by the tray. The pressure modules (130) are arranged horizontally and vertically in the upper chamber as needed and are configured to operate independently of each other so that the operation of any one pressure module is not affected by the operation of another pressure module.

[0030] In the above-described pressure module (130), a base member (135) is coupled to the upper side of the first upper surface (110) of the upper chamber, and an air cylinder (131) that generates pressure to be applied to the die and a load cell (133) that measures the pressure applied to the die are coupled to the base member (135). Then, a plurality of pressure blocks (150) are arranged to penetrate the first upper surface (110) of the upper frame and apply pressure by contacting the upper surface of the die. Each lower surface of the plurality of pressure blocks (150) applies pressure by contacting the upper surface of each die placed on the substrate. The plurality of pressure blocks (150) of the present invention may have different elastic moduli if necessary. Through this, different pressures can be applied to the die (40) on the substrate, and by utilizing this structure, the present invention enables the accurate application of the necessary pressure to be applied to the die for die bonding when the size and height of the die (40) are different.

[0031] The present invention is characterized by having a tilting structure that can apply the necessary pressure to the upper surface of the die (40) even when the size and height of the die (40) differ, and also can apply pressure evenly to the upper surface of the die (40) even when the substrate (20) is not horizontal and is tilted at a certain angle, and a structure for this is illustrated in FIGS. 2 to 5.

[0032] The pressure block (150) of the present invention is a block-shaped member and consists of a first member (152) on the upper side, a second member (153) located on the lower side in contact with the upper surface of the die, and an elastic connecting member (154) connecting the first member and the second member. Here, the first member (152) is attached to the base member (135) of the pressure module. The elastic connecting member (154) has an elastic body having a predetermined elastic modulus. The elastic modulus of the elastic connecting member is a numerical value representing the proportional relationship between the applied force and the strain, and in the present invention, the elastic modulus of the elastic connecting member can be adjusted differently for each pressure block (150). That is, the elastic modulus of one pressure block and the elastic modulus of another pressure block can be made different.

[0033] Various structures are possible to control the elastic modulus (elasticity modulus) of the elastic connecting member (154) of the above-mentioned pressure block (150). In the pressure block (150) illustrated in FIGS. 2 and 3, the shape of the elastic connecting member (154) itself is made in a zigzag shape to have a constant elasticity modulus against a load acting in the vertical direction. However, the elastic connecting member (154b) having a constant elastic modulus can be achieved with other structures, and for example, it may be possible to configure it as a spring to have a constant elasticity modulus against a load acting in the vertical direction. By utilizing such a structure, the pressure member of the present invention can control the pressure applied to the die by adjusting the strain of the elastic connecting member of the pressure block even in the case of dies (40) of different heights, and as a result, die bonding can be performed simultaneously even when the heights of the dies receiving pressure in a single pressure module (130) are different.

[0034] Referring to FIGS. 2 and 3, the pressure block (150) of the present invention is structured such that the first member (152) and the second member (153) are connected to the elastic connecting member (154), but the entire structure is not connected, and they are connected only in the central part. In other words, the part where the elastic connecting member, the first member (152), and the second member (153) are connected to each other is connected only at the central connecting part (155) in a state where the thickness width is reduced. Through this, tilting operation of the pressure block is possible, and the die bonding process is possible even when the substrate is tilted at a predetermined angle. FIGS. 2 and 3 illustrate some of the shapes of various embodiments of the pressure block.

[0035] In FIG. 4, the case where the substrate (20) is not horizontal and is tilted at a certain angle (θ) is illustrated in an exaggerated manner for the purpose of explanation. Due to the tilted substrate, the upper surface of the die (40) is also tilted by the angle (θ). However, in the present invention, due to the structure of the central connecting part (155) of the pressure block (150), the upper surface (A) of the first member (152) is horizontal, and the lower surface (B) of the second member (153) is tilted by the angle (θ), thereby enabling a tilting operation. The lower surface (B) of the second member (153) contacts the upper surface of the die (40) perpendicularly, thereby enabling uniform pressure to be applied to the upper surface of the die.

[0036] In the present invention, multiple pressure modules (130) are arranged in the horizontal and vertical directions in the upper chamber, and multiple pressure blocks (150) are arranged in the horizontal and vertical directions in one pressure module (130). The present invention is configured so that the pressure blocks coupled to the lower part of one pressure module can be attached and detached all at once. It includes a detachable member (140) that is detachably coupled to the lower surface of a base member (135) of the upper chamber, and multiple first members of the pressure blocks are coupled to the lower side of the base member (135). Furthermore, by detaching the detachable member (140) to the lower surface of the base member, the entire plurality of pressure blocks is replaced.

[0037] The upper surface of the first member (152) of the above-mentioned pressure block and the lower surface of the second member (153) are capable of tilting at a certain angle to each other, so as to provide uniform surface pressure to the die even when the die is slightly tilted when the lower surface of the second member of the above-mentioned pressure block presses the upper surface of the die, and for convenience, this is referred to as a response to the microscopic tilt state of the die.

[0038] In addition, the upper chamber of the present invention includes a plurality of pressure modules (130) arranged horizontally and vertically, and the plurality of pressure modules are configured to operate independently without affecting each other. This independent operation is intended to operate in such a way that uniform surface pressure can be applied in response to the slope (macroscopic slope) at the substrate level.

[0039] With the substrate and die entered into the bonding space, the upper chamber is fixed at a specific position, and the lower chamber moves toward the upper chamber to seal the bonding space. In other words, the present invention has a structure in which the lower chamber moves up and down.

[0040] In addition, the lower chamber of the present invention is equipped with a vacuum pump (300) and an exhaust pipe (350) so that gas inside the bonding space can be exhausted to the outside during the die bonding process. When the lower chamber and the upper chamber are in contact with each other and the bonding space is sealed, the vacuum pump (300) is operated to create a vacuum state inside the bonding space (S) at a certain level, making it possible to use copper (Cu) in the die bonding process. In the prior art, it was difficult to use copper in the die bonding process because oxidation occurs when copper is used, but the present invention solves this problem.

[0041] Figures 5 to 11 sequentially show the process of performing a die bonding process using the die bonding device of the present invention. Figure 5 shows the process of loading a tray (10) containing a substrate and a die into a bonding space while the lower chamber is separated from the upper chamber; Figure 6 shows the tray (10) being seated on a support of the lower chamber; Figure 7 shows the lower chamber moving upward to close the bonding space (S); Figure 8 shows the process of creating a vacuum state by operating the vacuum pump to discharge internal gas to the outside while the bonding space is sealed; Figure 9 shows the bonding space being heated by applying heat in a vacuum state and applying pressure to the die using a pressure module; Figure 10 shows the lower chamber moving downward to open; and Figure 11 shows the process of unloading the tray (10) containing a substrate and a die out of the bonding space while the lower chamber is separated from the upper chamber.

[0042] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims also fall within the scope of the present invention.

Claims

1. It consists of an upper chamber and a lower chamber that come into contact with each other to form a bonding space where the substrate and the die are bonded, and The above upper chamber is, An upper frame (110, 120) having a lower surface open, a first upper surface and a first side surface; and, A pressure module (130) that applies a predetermined pressure from the upper side to a die located in the bonding space and coupled to the first upper surface; and The above lower chamber is, A lower frame (210, 220) having an open upper surface, a second lower surface, and a second side; and, A support member (230) that supports a substrate located in the bonding space; is provided, The above pressure module (130) includes a plurality of pressure blocks (150) that are positioned through the first upper surface of the upper frame and apply pressure in contact with the upper surface of the die. A die bonding device characterized in that the plurality of pressure blocks have elastic bodies having different elastic moduli and apply different pressures to the die.

2. In Paragraph 1, The above pressure block (150) is, It is composed of a first member (152) attached to the above-mentioned pressure module, a second member (153) in contact with the upper surface of the die, and an elastic connecting member (154) connecting the first member and the second member. A die bonding device characterized in that the above elastic connecting member has a predetermined elastic modulus.

3. In Paragraph 2, A die bonding device characterized in that when the lower surface of the second member of the pressure block presses the upper surface of the die, the upper surface of the first member (152) of the pressure block and the lower surface of the second member (153) of the pressure block can tilt at a certain angle to each other, thereby providing uniform surface pressure to the die even in a microscopic tilted state of the die.

4. In Paragraph 3, The upper chamber above includes a plurality of pressurizing modules (130), and A die bonding device characterized in that the plurality of pressure modules above operate independently of each other to correspond to the macroscopic inclination of the substrate.

5. In paragraph 4, the above-mentioned pressurizing module (130) is, A die bonding device characterized by including a base member (135) to which an air cylinder that generates pressure applied to the above-mentioned pressure block and a load cell that measures pressure applied to the above-mentioned die are combined.

6. In paragraph 5, the above-mentioned pressurizing module (130) is, A plurality of first members of the above-mentioned pressure block are joined from the bottom, and further include a detachable member (140) that is detachably joined to the lower surface of the base member. A die bonding device characterized by the replacement of a plurality of pressure blocks as the detachable member of the above-mentioned pressure module is replaced.

7. In Paragraph 1, With the substrate and the die entered into the bonding space, A die bonding device characterized in that the upper chamber is fixed at a specific position, and the lower chamber moves toward the upper chamber to seal the bonding space.

8. In Paragraph 1, A die bonding device characterized by further including a vacuum pump (300) provided in the lower chamber and exhausting gas inside the bonding space to the outside.

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