Forming apparatus and forming method for sealing resin for compression molding

Abstract

The present invention addresses the problem of providing an apparatus and a method for forming a sealing resin capable of realizing a compression molding apparatus and a compression molding method capable of preventing the occurrence of molding defects. As a solution, the sealing resin forming device (100) forms a sealing resin (R) used for compression molding of a workpiece (W) by tabletting a base resin (Rm), and comprises a tabletting die (102), the sheet pressing mold (102) accommodates a predetermined amount of a base resin (Rm) in one or both of a pair of lower mold (106) and upper mold (104) that are opened and closed, and performs sheet pressing so as to form a sealing resin (R) having a predetermined shape corresponding to the shape of a workpiece (W).

Description

Technical Field

[0001] This invention relates to an apparatus and method for forming a sealant resin for compression molding. Background Technology

[0002] As an example of a resin sealing device and resin sealing method that uses a sealing resin to seal a workpiece on a substrate with electronic components and process it into a molded article, a resin sealing device and resin sealing method using compression molding is known.

[0003] Compression molding is performed by supplying a predetermined amount of sealing resin to a sealing area (mold cavity) of a sealing mold comprising an upper mold and a lower mold, placing a workpiece in the sealing area, and sealing the resin by clamping it with the upper and lower molds. As an example, it is known that when using a sealing mold with a mold cavity in the upper mold, sealing resin is supplied to the center of the workpiece for molding. On the other hand, it is known that when using a sealing mold with a mold cavity in the lower mold, a release film (hereinafter sometimes simply referred to as "film") covering the mold surface containing the mold cavity and sealing resin are supplied for molding (Patent Document 1: See Japanese Patent Application Publication No. 2019-145550).

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2019-145550 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] For example, when sealing a strip-shaped electronic component (semiconductor chip) connected by wires with resin, in a compression molding process where a cavity is provided in the upper mold, the wire portion of the workpiece held in the lower mold comes into contact with the sealing resin pre-supplied to the cavity or supplied to the workpiece, causing deformation and thus posing a problem of difficulty in resin sealing. Therefore, a compression molding process is generally adopted in which the workpiece is held in the upper mold, a cavity is provided in the lower mold, and sealing resin (for example, particulate resin) is supplied into the cavity.

[0009] However, in structures where the upper mold holds the workpiece and the lower mold has a cavity, there is a problem that the workpiece is difficult to hold in the upper mold and is prone to falling, especially if it is thin or large. Furthermore, in structures where sealing resin is typically supplied to the cavity of the lower mold as a diaphragm, if a thick molded article (here, the thickness of the resin portion after molding) is to be formed exceeding 1 mm, the molding stroke becomes longer, causing the diaphragm to bite into the molded article and resulting in poor molding. Moreover, when using particulate resin as the sealing resin, the aforementioned diaphragm biting is likely to occur. In addition, there is a problem not only of dust generation and difficulty in handling it, but also of difficulty in uniformly supplying (distributing) the sealing resin to the entire area within the cavity of the lower mold, resulting in uneven distribution. Furthermore, there is a problem that when distributing the sealing resin, air contained in the gaps between the particles and gas components generated during degassing of the sealing resin during melting cannot be expelled and remain in the molded article, easily leading to poor molding. Especially when workpieces containing electronic components are connected by wires, wire flow (deformation or breakage of the wires) may occur due to resin flow within the mold cavity during resin sealing.

[0010] Technical means to solve the problem

[0011] The present invention was made in view of the above circumstances, and its object is to provide a forming apparatus and a forming method for forming a sealing resin, wherein the sealing resin is easy to process, and can solve the problem of a structure in which a mold cavity is set in an upper mold and a structure in which a mold cavity is set in a lower mold, prevent molding defects caused by resin flow, uneven distribution, residual gas, and dust generation during molding, and form a molding article with a large thickness dimension.

[0012] The present invention addresses the aforementioned problem through the means described below as one embodiment.

[0013] One embodiment of the sealing resin forming apparatus is an apparatus for forming a compression-molded sealing resin for a workpiece by pressing a base resin into sheets. An essential requirement of this forming apparatus is that it includes a pressing mold that contains a predetermined amount of the base resin in one or both of a pair of lower and upper molds that open and close, and presses the resin into sheets such that it has a predetermined shape corresponding to the shape of the workpiece. For example, the workpiece used may be a workpiece having a structure in which electronic components are mounted on a substrate.

[0014] Alternatively, it is preferable to include: a lower mold film supply unit for supplying a release film adsorbed on the mold surface of the lower mold; and an upper mold film supply unit for supplying a release film adsorbed on the mold surface of the upper mold.

[0015] Furthermore, for the workpiece, the specified shape is preferably a shape in which the sealing resin does not come into contact with the electronic component when it is placed on the substrate, and the specified amount is preferably a amount set by measuring the number of electronic components mounted on a substrate for each workpiece and calculating the required amount of resin, or an amount selected and set from a variety of fixed amounts corresponding to the type of workpiece.

[0016] Furthermore, powdered resin is preferred as the base resin.

[0017] In another embodiment, a method for forming a sealing resin involves pressing a base resin into sheets to form a sealing resin for compression molding of a workpiece. An essential condition of this method is that it includes a pressing step in which a predetermined amount of the base resin is contained in a pressing mold and pressed into sheets to form the sealing resin having a predetermined shape corresponding to the shape of the workpiece.

[0018] The effects of the invention

[0019] If the sealing resin formed by the forming apparatus and forming method of the present invention is used, the problems of having a mold cavity in the upper mold and having a mold cavity in the lower mold can be solved, and molding defects caused by resin flow, uneven distribution, residual gas, and dust generation during molding can be prevented, resulting in molded articles with large thickness dimensions. In addition, compared with granular resins, handling during supply or installation becomes particularly easier. Attached Figure Description

[0020] [ Figure 1 ] Figure 1 This is a plan view showing an example of a compression molding apparatus for a sealing resin formed using the forming apparatus and forming method according to embodiments of the present invention.

[0021] [ Figure 2 ] Figure 2 This is an explanatory diagram illustrating an example of a compression molding method using a sealing resin formed by the forming apparatus and forming method according to embodiments of the present invention.

[0022] [ Figure 3 ] Figure 3 It is a continuation Figure 2 Explanatory diagram.

[0023] [ Figure 4 ] Figure 4 It is a continuation Figure 3 Explanatory diagram.

[0024] [ Figure 5 ] Figure 5This is an explanatory diagram illustrating another example of a compression molding method using a sealing resin formed by the forming apparatus and forming method according to embodiments of the present invention.

[0025] [ Figure 6 ] Figure 6 It is a continuation Figure 5 Explanatory diagram.

[0026] [ Figure 7 ] Figure 7 It is a continuation Figure 6 Explanatory diagram.

[0027] [ Figure 8 ] Figure 8 This is a side view showing an example of a sealing resin forming apparatus according to an embodiment of the present invention.

[0028] [ Figure 9 ] Figure 9 It means Figure 8 A front cross-sectional view of an example of a tableting mold for forming apparatus.

[0029] [ Figure 10 ] Figure 10 This is an explanatory diagram of a method for forming a sealing resin according to an embodiment of the present invention.

[0030] [ Figure 11 ] Figure 11 It is a continuation Figure 10 Explanatory diagram.

[0031] [ Figure 12 ] Figure 12 It is a continuation Figure 11 Explanatory diagram.

[0032] [ Figure 13 ] Figure 13 This is a perspective view showing an example of a sealing resin formed by the forming apparatus and forming method according to an embodiment of the present invention.

[0033] [ Figure 14 ] Figure 14 This is a perspective view showing another example of a sealing resin formed by the forming apparatus and forming method according to embodiments of the present invention.

[0034] [ Figure 15 ] Figure 15 This is a perspective view showing another example of a sealing resin formed by the forming apparatus and forming method according to embodiments of the present invention.

[0035] [ Figure 16 ] Figure 16 This is a perspective view showing another example of a sealing resin formed by the forming apparatus and forming method according to embodiments of the present invention.

[0036] [ Figure 17 ] Figure 17 A is Figure 2 Enlarged view of part A in the image. Figure 17 B is a continuation. Figure 17 Explanation diagram for A.

[0037] [ Figure 18 ] Figure 18 This is an illustration of an existing compression molding method.

[0038] [ Figure 19 ] Figure 19 This is an illustration of an existing compression molding method.

[0039] [ Figure 20 ] Figure 20 This is a front cross-sectional view of another example of a tableting mold of a forming apparatus according to an embodiment of the present invention. Detailed Implementation

[0040] (Compression forming apparatus and compression forming method)

[0041] The sealing resin forming apparatus and method according to embodiments of the present invention are apparatuses and methods for forming a sealing resin R for compression molding of a workpiece W. First, a general outline of the compression molding apparatus 1 and compression molding method for resin sealing (compression molding) of the workpiece W using the sealing resin R will be described. Here, Figure 1 This is a plan view (schematic view) showing an example of the compression forming apparatus 1.

[0042] The workpiece W, which is the object to be sealed, includes a structure in which electronic components Wb are mounted on a substrate Wa. More specifically, examples of the substrate Wa include plate-shaped components such as resin substrates, ceramic substrates, metal substrates, transport plates, lead frames, and wafers. Examples of electronic components Wb include semiconductor chips, microelectromechanical system (MEMS) chips, passive components, heat sinks, conductive components, and gaskets. Furthermore, the substrate Wa can be rectangular (strip-shaped), square, circular, or similar shapes. Additionally, the number of electronic components Wb mounted on a substrate Wa is set to one or more (e.g., in a matrix).

[0043] Examples of methods for mounting electronic components Wb on a substrate Wa include wire bonding packaging and flip-chip packaging. Alternatively, in cases where the substrate (glass or metal carrier plate) Wa is peeled off from the molded article Wp after resin sealing, methods such as using heat-removable adhesive tape or UV-curable resin that hardens under ultraviolet light can be used to attach the electronic components Wb.

[0044] Furthermore, as examples of membrane F, membrane materials with excellent heat resistance, ease of peeling, flexibility, and stretchability are preferred, such as polytetrafluoroethylene (PTFE), ethylene-tetrafluoroethylene (ETFE) (a polytetrafluoroethylene polymer), polyethylene terephthalate (PET), fluorinated ethylene propylene (FEP), fluorinated glass cloth, polypropylene, and polyvinylidene chloride. In addition, membrane F is also used in the forming apparatus 100 described later when forming the sealing resin R.

[0045] like Figure 1 As shown, the compression molding apparatus 1 includes the following main components: a supply unit 10A for supplying workpiece W; a pressing unit 10B for sealing workpiece W with resin to process molded product Wp; and a storage unit 10C for storing molded product Wp. As an example, along... Figure 1 In the X direction, a supply unit 10A, a pressing unit 10B, and a storage unit 10C are arranged sequentially. However, the structure is not limited to the above, and the equipment structure or the number of units (especially the number of pressing units), the arrangement order of the units, etc., can be changed. Alternatively, the structure can include units other than those described above (none are shown).

[0046] Furthermore, in the compression molding apparatus 1, the guide rail 20 is arranged in a straight line spanning between each unit. The conveying device (first loader) 22 for conveying the workpiece W and the sealing resin R, and the conveying device (second loader) 24 for conveying the molded product Wp (which can also be used for conveying the sealing resin R) are arranged in a manner that allows them to move along the guide rail 20 between predetermined units. However, this structure is not limited to the above; it may also be configured to include a common (one) conveying device (loader) for conveying the workpiece W, the sealing resin R, and the molded product Wp (not shown). Additionally, the conveying device may be configured to include a robot arm or the like instead of a loader.

[0047] In addition, in the compression molding apparatus 1, the control unit 30 that controls the operation of each mechanism in each unit is arranged in the supply unit 10A (or may be arranged in other units).

[0048] The pressing unit 10B includes a pair of sealing molds that are opened and closed by the pressing device 250. As an example, the sealing molds may be configured with a cavity in the upper mold (sealing mold 202), or as another example, with a cavity in the lower mold (sealing mold 302). Furthermore, the pressing device 250 is provided with a film supply section 211, which supplies film F to cover the mold surface 204a (a defined area) of the upper mold 204, which includes the inner surface of the cavity 208. Additionally, as an example, the film F is roller-shaped, but it may also be strip-shaped.

[0049] As an example, refer to Figures 2-4 The process of the compression forming method implemented using the compression forming apparatus 1 including the sealing mold 202 will be described.

[0050] First, a preparation process (sealing preparation process) is performed. Specifically, this involves adjusting the upper mold 204 and lower mold 206 to a specified temperature (e.g., 100°C to 300°C) and heating them. Next, a process is performed where the film supply unit 211 is operated to supply a new film F, which is then adsorbed onto a specified area of ​​the mold surface 204a, including the inner surface of the mold cavity 208, within the upper mold 204.

[0051] After the preparation process, a workpiece holding process is performed to hold the workpiece W in the workpiece holding part 205 of the lower mold 206. Specifically, the workpiece W supplied from the supply box 12 is held by the first loader 22 and moved into the sealing mold 202 and held in the workpiece holding part 205 of the lower plate 242 (mold surface 206a).

[0052] After the workpiece holding process, a resin loading process is performed where sealing resin R is loaded onto the workpiece W held in the workpiece holding part 205 (see reference). Figure 2 Specifically, the sealing resin R formed in the sealing resin forming apparatus (sometimes simply referred to as the "forming apparatus") 100, which is held by the first loader 22 (or other conveying device), is transported into the sealing mold 202 and placed on the workpiece W held in the workpiece holding part 205.

[0053] Alternatively, as another example of the resin loading process, it can be implemented as a process in which the sealing resin R formed in the forming apparatus 100 is placed on top of the workpiece W before the workpiece holding process. In this case, the workpiece holding process becomes a process of holding the workpiece W, which is in a state of having the sealing resin R loaded, in the workpiece holding portion 205. That is, the first loader 22 holds the workpiece W, which is in a state of having the sealing resin R loaded, and moves the workpiece W into the sealing mold 202, and holds it in the workpiece holding portion 205. This has the advantage that the workpiece W and the sealing resin R are moved into the sealing mold 202 at one time, instead of being moved into the sealing mold 202 separately.

[0054] Next, a resin sealing process is performed to seal the workpiece W with sealing resin R to form a molded product Wp. Specifically, a mold closing process is performed by closing the sealing mold 202 and relatively lowering the mold cavity component 226 within the mold cavity 208 surrounded by the clamping device 228, thereby heating and pressurizing the workpiece W with the sealing resin R. As a result, the sealing resin R is thermo-hardened, thus completing the resin sealing (compression molding) (see reference). Figure 3 ).

[0055] Furthermore, the subsequent processes following the mold closing process are the same as those in existing compression molding methods. In summary, the mold opening process involves opening the sealing mold 202, separating the molded article Wp from the used film F, and removing the molded article Wp (see [reference]). Figure 4 Next, a molding article removal process is performed, in which the molded article Wp is removed from the sealing mold 202 and transported to the storage unit 10C by the second loader 24. As an example, the removed molding article Wp is stored in the storage box 14. In addition, a process is performed after or in parallel with the molding article removal process, in which the film supply unit 211 is operated to send the used film F out of the sealing mold 202, and a new film F is sent in and installed in the sealing mold 202.

[0056] The above describes the main steps of the compression molding method using the compression molding apparatus 1, which includes the sealing mold 202. However, the sequence of these steps is just one example, and the order can be changed or the steps can be performed in parallel as long as it does not cause problems.

[0057] As another example, see Figures 5-7 The steps of the compression molding method implemented using the compression molding apparatus 1, including the sealing mold 302, will be described. In this case, a film supply unit 311 is provided in the pressing device 250, which supplies film F to cover the mold surface 306a (a defined area) in the lower mold 306, which includes the inner surface of the mold cavity 308. Furthermore, as an example, the film F is in the shape of a roller, but it may also be in the shape of a strip.

[0058] First, a preparation process (sealing preparation process) is performed. Specifically, this involves adjusting the upper mold 304 and lower mold 306 to a specified temperature (e.g., 100°C to 300°C) and heating them. Next, a process is performed where the film supply unit 311 is operated to supply a new film F, which is then adsorbed onto a specified area of ​​the mold surface 306a, including the inner surface of the mold cavity 308, in the lower mold 306.

[0059] After the preparation process, a workpiece holding process is performed to hold the workpiece W in the workpiece holding part 305 of the upper mold 304. Specifically, the workpiece W supplied from the supply box 12 is held by the first loader 22 and moved into the sealing mold 302 and held in the workpiece holding part 305 on the upper plate 342 (mold surface 304a).

[0060] The resin holding process is performed after the workpiece holding process (or it can be performed before or in parallel with the workpiece holding process). The resin holding process includes the following steps: Holding the sealing resin R within the mold cavity 308 of the lower mold 306 (see reference). Figure 5 Specifically, the sealing resin R formed in the forming apparatus 100 is held by the first loader 22 (or other conveying device) and transported into the sealing mold 302 and housed in the mold cavity 308 (specifically, placed on the upper surface of the mold cavity module 326).

[0061] Next, a resin sealing process is performed to seal the workpiece W with sealing resin R to form a molded product Wp. Specifically, the sealing mold 302 is closed, and the mold cavity component 326 is relatively raised within the mold cavity 308 surrounded by the clamping device 328 to heat and pressurize the workpiece W with the sealing resin R in a mold closing process. As a result, the sealing resin R is thermo-hardened, thereby completing the resin sealing (compression molding) (see reference). Figure 6 ).

[0062] Furthermore, the subsequent processes following the mold closing process are the same as those in existing compression molding methods. In summary, the mold opening process involves opening the sealing mold 302, separating the molded article Wp from the used film F, and removing the molded article Wp (see [reference]). Figure 7 Next, a molding article removal process is performed, in which the molded article Wp is removed from the sealing mold 302 and transported to the storage unit 10C by the second loader 24. As an example, the removed molding article Wp is stored in the storage box 14. In addition, a process is performed after or in parallel with the molding article removal process, in which the film supply unit 311 is operated to send the used film F out of the sealing mold 302, and a new film F is sent in and installed in the sealing mold 302.

[0063] The above are the main steps of the compression forming method using the compression forming apparatus 1 including the sealing mold 302. However, the sequence of these steps is just one example, and the order can be changed or carried out in parallel as long as it does not cause problems.

[0064] (Apparatus for forming sealing resin)

[0065] Then, referring to Figure 8 , Figure 9 The forming apparatus 100 for forming the sealing resin R used in the compression molding apparatus 1 and the compression molding method will be described. The forming apparatus 100 processes a base resin Rm to form the sealing resin R. Here, Figure 8 This is a side view (schematic view) showing an example of the forming apparatus 100. Furthermore, the forming apparatus 100 may be disposed either inside or outside the compression forming apparatus 1.

[0066] In this embodiment, a thermosetting resin (e.g., an epoxy resin containing fillers, but not limited thereto) is used as both the base resin Rm and the sealing resin R formed from the base resin Rm. The sealing resin R is formed as a solid / semi-solid resin having a predetermined shape (details will be described later) that corresponds to the shape of the workpiece W as a whole. Typically, it is formed as a "whole" that forms the required amount of sealing (the amount for each workpiece W at one time), but it can also be configured as a "whole" that forms the required amount of sealing in multiple (e.g., two, three or so) segmented states. In addition, the term "semi-solid" refers to a state that is not completely solid but melted to the so-called B stage. Furthermore, the base resin Rm preferably uses a powdered resin (form) as a thermosetting resin (property) (details will be described later). However, it is not limited thereto, and it can also be configured to use a structure of granular resin, fragmented resin, solid resin, liquid resin, or a combination of several of these.

[0067] like Figure 8 As shown, the forming apparatus 100 includes a tableting mold 102, which has a pair of molds for opening and closing (e.g., a mold assembled from multiple mold blocks, mold plates, mold pillars, or other components made of alloy tool steel). Additionally, it includes a pressing device 150 for driving the opening and closing of the tableting mold 102. Here, Figure 9 This is a front cross-sectional view (simplified view) showing an example of a tableting mold 102.

[0068] like Figure 8As shown, the pressing device 150 comprises a pair of pressing plates 154 and 156, a plurality of pull rods 152 supporting the pair of pressing plates 154 and 156, and a drive device for making the pressing plate 156 movable (lifting and lowering). Specifically, the drive device comprises a drive source (e.g., an electric motor) 160 and a drive transmission mechanism (e.g., a ball screw or toggle mechanism) 162, etc. (however, it is not limited to this). In this embodiment, the pressing plate 154 on the upper side in the vertical direction is set as a fixed pressing plate (the pressing plate fixed to the pull rod 152), and the pressing plate 156 on the lower side is set as a movable pressing plate (the pressing plate that can be slidably held in place by the pull rod 152 and lifted and lowered). However, it is not limited to this, and the two sides can be reversed, that is, the upper side can be set as a movable pressing plate and the lower side as a fixed pressing plate, or both the upper and lower sides can be set as movable pressing plates (neither shown).

[0069] On the other hand, such as Figure 9 As shown, the tablet compression mold 102 includes an upper mold 104 on the upper side and a lower mold 106 on the lower side in the vertical direction, serving as a pair of molds disposed between the pair of pressure plates 154 and 156 in the compression device 150. The upper mold 104 is assembled to the upper pressure plate (a fixed pressure plate 154 in this embodiment), and the lower mold 106 is assembled to the lower pressure plate (a movable pressure plate 156 in this embodiment). The mold is closed / opened by the upper mold 104 and the lower mold 106 approaching / moving away from each other (the vertical direction (up and down direction) is the mold opening and closing direction). In the tablet compression mold 102 of this embodiment, the upper mold 104 is configured as a so-called "pestle type", and the lower mold 106 is configured as a so-called "mortar type".

[0070] Next, the lower mold 106 of the tableting mold 102 will be described in detail. For example... Figure 9 As shown, the lower mold 106 includes a lower mold groove 110, a mold cavity component 126 held therein, a clamping device 128, etc. The lower mold groove 110 is fixed to the upper surface of the support plate 114 via a support post 112. A mold cavity 108 is provided on the upper surface of the lower mold 106 (the surface on the side of the upper mold 104). A predetermined amount of base resin Rm is contained in the mold cavity 108.

[0071] The clamp 128 is configured in a ring shape to surround the mold cavity module 126, and is assembled in a manner that allows it to move up and down independently (floatingly) relative to the upper surface of the support plate 114 via a push pin 122 and a clamping spring 124 (e.g., a force-applying member exemplified by a coil spring) (however, this assembly structure is not limited to this). The mold cavity module 126 forms the interior (bottom) of the mold cavity 108, and the clamp 128 forms the side of the mold cavity 108. Furthermore, the shape or number of mold cavities 108 provided in a lower mold 106 is suitably configured (one or more).

[0072] Here, the pressing device 150 is provided with a lower mold film supply section 111, which supplies a film F to cover the mold surface 106a (a defined area) in the lower mold 106, which includes the inner surface of the mold cavity 108. Furthermore, as an example, the film F is roller-shaped, but it can also be strip-shaped.

[0073] Furthermore, the lower mold 106 is provided with a suction path (hole or groove, etc.) (not shown) that communicates with the suction device on the upper surface of the clamp 128 or at the boundary between the clamp 128 and the mold cavity 126. As a result, the film F supplied from the lower mold film supply section 111 can be adsorbed and held on the mold surface 106a containing the inner surface of the mold cavity 108.

[0074] In addition, in this embodiment, a lower mold heating mechanism (not shown) is provided to heat the lower mold 106 to a predetermined temperature. The lower mold heating mechanism includes a heater (e.g., an electric heating wire heater), a temperature sensor, a power supply, etc., and the heating is controlled by the control unit 30. As an example, the heater is built into the lower mold groove 110 and applies heat to the entire lower mold 106 and the base resin Rm housed within the mold cavity 108. At this time, the lower mold 106 is heated so that the base resin Rm reaches a predetermined temperature (e.g., 50°C to 80°C) to a level that prevents heat curing (formal curing).

[0075] Next, the upper mold 104 of the tableting mold 102 will be described in detail. For example... Figure 9 As shown, the upper mold 104 includes a pressing plate 142, which is formed (pressed) into a sealing resin R having a predetermined shape corresponding to the shape of the workpiece W by pressing a predetermined amount of base resin Rm housed in the mold cavity 108 of the lower mold 106 (details of the forming method will be described later). The pressing plate 142 is held (fixed) in the upper mold groove 140. As an example, a foot forming groove (including a recess) 143 for forming the foot Rb of the sealing resin R is provided on the lower surface of the pressing plate 142 (the surface on the side of the lower mold 106).

[0076] Here, the pressing device 150 is provided with an upper mold film supply section 113, which supplies film F for covering the mold surface 104a (a designated area) of the upper mold 104. Furthermore, as an example, the film F is roller-shaped, but it can also be strip-shaped.

[0077] In addition, the upper mold 104 is provided with a suction path (hole or groove, etc.) (not shown) that communicates with the suction device on the pressing plate 142, etc. As a result, the film F supplied from the upper mold film supply section 113 can be adsorbed and held on the mold surface 104a.

[0078] In addition, in this embodiment, an upper mold heating mechanism (not shown) is provided to heat the upper mold 104 to a predetermined temperature. The upper mold heating mechanism includes a heater (e.g., an electric heating wire heater), a temperature sensor, a power supply, etc., and the heating is controlled by a control unit 30. As an example, the heater is built into the upper mold groove 140 and applies heat to the entire upper mold 104. At this time, the upper mold 104 is heated to a predetermined temperature (e.g., 50°C to 80°C) so that the base resin Rm contained in the lower mold 106 is kept at a level that prevents heat curing (formal curing).

[0079] (Method for forming sealing resin)

[0080] Next, the steps of the sealing resin forming method of this embodiment, implemented using the forming apparatus 100, will be described. Here, Figures 10-12 These are explanatory diagrams of each process, and are used as a reference for... Figure 9 The figures are shown as frontal cross-sections in the same direction.

[0081] First, a preparation process (tablet preparation process) is performed. This preparation process includes the following steps: A lower mold heating process is performed, in which the lower mold 106 is adjusted to a specified temperature (a temperature at which the base resin Rm and sealing resin R will not fully harden, for example, 50°C to 80°C) by a lower mold heating mechanism and then heated. Additionally, an upper mold heating process is performed, in which the upper mold 104 is adjusted to a specified temperature (a temperature at which the base resin Rm and sealing resin R will not fully harden, for example, 50°C to 80°C) by an upper mold heating mechanism and then heated. Furthermore, a lower mold film supply process is performed, in which a new film F is supplied by operating the lower mold film supply unit 111, and adsorbed onto a specified area of ​​the mold surface 106a, which includes the inner surface of the mold cavity 108, in the lower mold 106. Additionally, a higher mold film supply process is performed, in which a new film F is supplied by operating the upper mold film supply unit 113, and adsorbed onto a specified area of ​​the mold surface 104a in the upper mold 104.

[0082] After the preparation process, a pressing process is performed, namely, a solid / semi-solid resin as sealing resin R is formed by pressing the base resin Rm into a sheet with a predetermined shape (described later) corresponding to the shape of the workpiece W. Specifically, a predetermined amount of base resin Rm is contained in the mold cavity 108 of the lower mold 106 using a dispenser or the like (not shown). Figure 10 Next, the pressing device 150 is operated to close the tableting mold 102, which has been heated to the specified temperature (see reference). Figure 11At this time, the mold cavity module 126 rises relative to the mold cavity 108, and the base resin Rm is compressed (clamped and pressurized) by the mold cavity module 126 and the pressing plate 142. This forms a solid / semi-solid sealing resin R with a predetermined shape and in a state where it has not undergone thermosetting (formal curing). At this time, the base resin Rm that enters the foot forming groove 143 of the pressing plate 142 via the membrane F becomes the foot Rb of the sealing resin R, and the remaining base resin Rm becomes the main body Ra of the sealing resin R (the detailed structure of the sealing resin R will be described later). Furthermore, as a variation of the pressing process, a portion of a predetermined amount of base resin Rm may be held (melted, held, etc.) in the upper mold 104 (not shown). The foot forming groove 143 is provided in the pressing plate 142, but it may also be provided in the mold cavity module 126, or both.

[0083] The tableting process is importantly carried out at a temperature at which the base resin Rm will not undergo thermosetting (formal curing) (by heating the lower mold 106 and upper mold 104 to a temperature at which thermosetting (formal curing) will not occur), so that the resulting sealing resin R can undergo thermosetting (formal curing) in a subsequent resin sealing process (a process in the compression molding method). As mentioned above, the "temperature at which thermosetting will not occur" depends on the material of the base resin Rm, but as a specific example, it is about 50°C to 80°C (about 70°C in this embodiment).

[0084] Here, the "prescribed shape" of the sealing resin R will be explained. As an example, in the case of the sealing resin R used in the compression molding apparatus 1 including the sealing mold 202, the "prescribed shape" is a shape that does not come into contact with the electronic component Wb (an electronic component Wb having wires includes wires) when placed on the substrate Wa of the workpiece W. As an example, such as... Figure 2 As shown, the sealing resin R preferably has the following shape: a sealing resin R having a plate-like or block-like main body Ra and a foot Rb that is intermittently (or continuously) erected on one side of the main body Ra (the side facing the electronic component Wb of the workpiece W). The main body Ra is preferably the size that enters the mold cavity 208 when viewed from above, and is slightly smaller than the shape of the mold cavity 208 (especially the mold cavity module 226) when considering resin flow. Additionally, the foot Rb needs a height H that does not contact the electronic component Wb (refer to...). Figure 17A), but this does not preclude contact to the extent that the wires do not undergo plastic deformation. Furthermore, the foot Rb is positioned so that it does not contact the electronic component Wb when viewed from above the main body Ra, and the main body Ra does not tilt when placed on the substrate Wa of the workpiece W. Moreover, it is preferable to position it between or around the electronic components Wb so that the wiring (especially the wires) of the workpiece W is not damaged during molding. In addition, the total resin amount of the plate-like or block-like main body Ra and the foot Rb can be a sufficient amount of resin, not insufficient for a single compression molding, or it can be an excessive amount of resin. Specific structural examples of the sealing resin R ( Figures 13-16 Details will be provided later.

[0085] As another example, in the case of the sealing resin R used in the compression molding apparatus 1 including the sealing mold 302, the "prescribed shape" is as follows: when the sealing mold 302 is closed, the upper mold 304 gradually approaches the lower mold 306, and the front end (upper end) of the foot portion Rb of the sealing resin R housed in the mold cavity 308 abuts against the substrate Wa of the workpiece W held in the workpiece holding portion 305, the main body portion Ra of the sealing resin R does not abut against the electronic component Wb of the workpiece W (the electronic component Wb with wires includes wires). Furthermore, the specific shape of the sealing resin R is the same as that of the sealing resin R used in the compression molding apparatus 1 including the sealing mold 202 described above (see reference). Figure 17 A, Figures 13-16 Therefore, repeated descriptions are omitted. However, the sealing resin R is not limited to... Figure 17 A, Figures 13-16 The structure shown can also be configured such that the upper surface is flat without the foot Rb (not shown).

[0086] Next, the resin quantity setting process for setting the "prescribed amount" of the base resin Rm will be explained. As an example of the resin quantity setting process, for each workpiece W to be sealed, the quantity of electronic components Wb mounted on a substrate Wa is measured using a measuring mechanism (not shown) (the quantity may be the number of components mounted or missing, and may also include measuring the height of the electronic components Wb). The total volume of the electronic components Wb is subtracted from the volume of the sealing mold 202, the sealing mold 302 cavity 208, and the mold cavity 308. The control unit 30 then calculates the amount of resin (in grams) required for resin sealing (compression molding) and sets the "prescribed amount". Alternatively, as another example of the resin quantity setting process, multiple fixed quantities corresponding to the type of workpiece W to be sealed are prepared. The control unit 30 or the operator selects the most preferred one from the fixed quantities based on the type of workpiece W and sets the "prescribed amount". In the case of fixed quantities, it is important that the resin quantity is not insufficient during resin sealing (compression molding). An appropriate amount of base resin Rm can be supplied to the workpiece W through any setting. Therefore, it can in particular prevent molding defects caused by insufficient resin quantity required for resin sealing. Furthermore, it can prevent waste caused by supplying more resin than required.

[0087] Furthermore, powdered resin is preferably used as the base resin Rm. This allows for extremely precise adjustment and supply of the "prescribed amount" of resin compared to using granular or broken resin. However, it is not limited to powdered resin.

[0088] After the tableting process, the tableting mold 102 is opened, and the sealing resin R is separated from the used film F and the sealing resin R is removed (see [reference]). Figure 12 In this embodiment, by including the lower mold film supply process and the upper mold film supply process, the film F is disposed on both the mold surface 106a of the lower mold 106 and the mold surface 104a of the upper mold 104. Therefore, the demolding of the sealing resin R formed by pressing becomes easy, thereby preventing defects caused by resin adhering to the mold.

[0089] After the mold opening process, or in parallel, the following film supply process (lower mold film supply process and upper mold film supply process) is performed: the lower mold film supply unit 111 and the upper mold film supply unit 113 are operated to send the used film F out of the tableting mold 102, and a new film F is sent in and installed in the tableting mold 102.

[0090] (Sealing resin)

[0091] The specific structure of the sealing resin R formed by the forming apparatus and forming method described above will then be illustrated in the following example. Figures 13-16 The text describes the characteristics of each element.

[0092] First of all, as Figures 13-16 In the common structures shown in the examples, the main body Ra is formed in a plate shape (or it can be a shape other than a plate shape, such as a block shape with concave or convex portions). Furthermore, the foot Rb is erected on the main body Ra at a predetermined position (designed position) where it does not come into contact with the electronic component Wb of the workpiece W when the sealing resin R is placed on the substrate Wa of the workpiece W, and is formed at a height H (refer to) a distance that ensures the main body Ra does not come into contact with the electronic component Wb. Figure 17 A). As described above, in the tableting process, the base resin Rm that enters the foot forming groove 143 of the tableting plate 142 via the membrane F becomes the foot Rb of the sealing resin R, and the other (remaining) base resin Rm becomes the main body Ra of the sealing resin R.

[0093] exist Figure 13 In the example of the sealing resin R shown, the foot Rb is formed as a convex body Rb1 that is entirely (or partly) arranged in a dotted pattern. As an example, the convex body Rb1 is disposed at multiple locations and is formed such that, in a top view, the ratio t of length L1 to width W1 is, for example, 0.5 ≤ t ≤ 2. Therefore, by having the foot Rb as a columnar structure with dotted arrangements, the flow of the sealing resin R placed on the workpiece W during compression molding can be suppressed. Thus, wire flow and the like can be prevented, thereby improving molding quality.

[0094] exist Figure 14 In the example of the sealing resin R shown, the foot Rb is formed as a partially (or entirely) linearly arranged convex body Rb2. As an example, the convex body Rb2 is disposed at one (or multiple) location and is shaped such that, in plan view, the ratio t of its length L2 to its width W2 is, for example, t < 0.5 or 2 < t. Accordingly, resin flow can be intentionally generated from the foot Rb (in this case, the convex body Rb2) with a dam-like structure of a predetermined length to facilitate the filling of the sealing resin R into narrow portions of the workpiece W (e.g., between a substrate Wa connected via flip chip and an electronic component Wb). Therefore, gas residue in the molded article Wp can be prevented, thereby improving molding quality.

[0095] exist Figure 15In the example of the sealing resin R shown, the foot Rb is formed as a convex body Rb3 arranged in a way that intermittently (or continuously) surrounds the entire area (outer edge region) of the outer periphery (the outer edge region) of the main body Ra. As an example of the convex body Rb3, convex bodies with the same structure as Rb2 are formed by providing gaps L3 at predetermined intervals and are connected circumferentially. Generally, the outer periphery of the sealing resin R in the molded article Wp is the position cut by a slicing machine or the like during monolithic molding, and there are no electronic components Wb there. Therefore, more resin is needed for sealing compared to the central position. Therefore, by providing a foot Rb (in this case, a convex body Rb3) arranged to surround the entire outer periphery, as described above, more resin can be supplied to the outer periphery while suppressing resin flow during compression molding. Furthermore, by providing gaps L3, the discharge of gaseous components such as air from the inside (central part) to the outside can be promoted.

[0096] on the other hand, Figure 16 The example of the sealing resin R shown is a structural example related to the other side of the main body Ra (the side without the foot Rb, i.e., the side not facing the electronic component Wb of the workpiece W). Specifically, on the other side of the main body Ra, a linear groove Rg is formed at the position where a single-piece cutting is performed. This reduces the wear of the cutting edge and the dust generated during cutting. As an example, the groove Rg is set in a grid pattern consistent with the cutting position, but it is not limited to this. Furthermore, to form the groove Rg, a pressing process can be performed using a mold cavity mold 126 with protrusions (not shown) of a corresponding shape on its upper surface.

[0097] As explained above, if the sealing resin R formed by the forming apparatus and forming method of the present invention is used, a compression molding apparatus and compression molding method that achieve the following effects can be realized. Specifically, the compression molding apparatus and compression molding method can prevent molding defects caused by resin flow, uneven distribution, residual gas, and dust generation during molding. Furthermore, not only can thin molded articles Wp (thickness less than 1 mm) be formed, but thick molded articles Wp (thickness of 1 mm or more) can also be formed. Moreover, although the upper limit of the thickness depends on various setting conditions, it is considered that it can be sufficiently formed to about 10 mm. In addition, handling during supply or installation becomes easier.

[0098] Furthermore, the problems arising when a structure with a mold cavity in the upper mold can be solved by the aforementioned compression molding apparatus and compression molding method. Specifically, in conventional compression molding apparatuses with a mold cavity in the upper mold, for example, during the mold closing process on a workpiece W such as a wire-connected electronic component (semiconductor chip) Wb mounted on a strip, the wire portion of the workpiece held in the lower mold comes into contact with the sealing resin pre-supplied to the mold cavity or supplied to the workpiece, causing deformation and breakage, thus resulting in difficulties in resin sealing. To address this problem, a structure is adopted that uses a sealing resin R formed by the apparatus and method of this embodiment, i.e., a solid / semi-solid resin formed into a predetermined shape corresponding to the shape of the workpiece W.

[0099] Specifically, during the mold closing process, from Figure 17 A is transferred to Figure 17 Method B involves softening and melting the sealing resin R through heating (in addition, Figure 17 A, Figure 17 B as Figure 2 (See the enlarged view of part A in the diagram). At this point, the resin (specifically, the main body Ra) is in a state where it is evenly in contact with all the wires (see reference). Figure 17 B). Therefore, it can prevent the wire from deforming or breaking.

[0100] Furthermore, when the inventors of this application conducted experiments using the sealing resin R formed by the apparatus and method of this embodiment in the compression molding apparatus 1, they confirmed that, compared with the existing compression molding apparatus having a structure that holds the workpiece W in the upper mold, provides a mold cavity in the lower mold, and supplies sealing resin (specifically, particulate resin) to the mold cavity, the deformation and cutting of the wire can be prevented, and the molding quality is improved.

[0101] On the other hand, the problems arising when a structure with a mold cavity in the lower mold can also be solved by the aforementioned compression molding apparatus and compression molding method. Specifically, in existing compression molding apparatuses with a mold cavity in the lower mold, especially when using particulate resin as the sealing resin, the particle size or height (layer thickness) of the sealing resin (particulate resin) contained in the mold cavity does not become uniform. Therefore, for example, depending on the type and melt state of the particulate resin, it may not become completely liquid (low viscosity state), and the following problem exists: when performing a mold closing process on a workpiece W, such as one carrying a strip-shaped electronic component (semiconductor chip) Wb connected by wires, such as… Figure 18 As shown, depending on the position, the conductive portion of the workpiece held in the upper mold may come into strong (obvious) localized contact with the sealing resin (granular resin), resulting in deformation or breakage. Furthermore, as... Figure 19As shown, there is a problem where resin flow within the mold cavity is significant, causing deformation and breakage of the conductive wire. This problem can be solved by employing a structure that uses a sealing resin R formed by the apparatus and method of this embodiment, i.e., a solid / semi-solid resin formed into a predetermined shape corresponding to the shape of the workpiece W.

[0102] Specifically, as described above Figure 17 A, Figure 17 The reason given in explanation B is the same: during the mold closing process, the sealing resin R softens and melts due to heating, resulting in a state where the resin (specifically, the main body Ra) uniformly contacts all the wires. From this perspective, the sealing resin R is not limited to... Figures 13-16 The structure shown can also be configured such that the upper surface is flat without the feet Rb (not shown). This structure, compared to existing technologies using particulate resin, solves the problem caused by inhomogeneity in particle size or height (layer thickness). Furthermore, by making the sealing resin R forming apparatus 100 and the compression molding apparatus 1 separate, the compression molding apparatus 1 can be configured to be unaffected by dust during tableting of the powdered resin within the forming apparatus 100, thus allowing easy placement of the compression molding apparatus 1 into a cleanroom. Furthermore, as an example, the tableting mold 102 of the forming apparatus 100 has a structure with a movable clamp 128; other examples, of course, could also be as follows... Figure 20 The structure shown does not have a movable gripper.

[0103] Furthermore, the present invention is not limited to the described embodiments, and various modifications can be made without departing from the scope of the present invention.

Claims

1. An apparatus for forming a sealing resin, which forms a sealing resin for compression molding of a workpiece by pressing a base resin into sheets. The forming apparatus is characterized by including a tableting mold. The tableting mold contains a predetermined amount of the base resin in one or both of a pair of lower and upper molds that open and close the mold, and performs tableting in such a way that it becomes the sealing resin having a predetermined shape corresponding to the shape of the workpiece.

2. The sealing resin forming apparatus according to claim 1, characterized in that, The workpiece used is one having a structure in which electronic components are mounted on a substrate. The specified shape is the shape in which the sealing resin does not come into contact with the electronic component when it is placed on the substrate.

3. The apparatus for forming sealing resin according to claim 2, characterized in that, The workpiece used is one having a structure in which electronic components are mounted on a substrate. The specified amount is a quantity set for each workpiece by measuring the number of electronic components mounted on a substrate and calculating the required amount of resin, or a quantity selected and set from a variety of standardized amounts corresponding to the type of workpiece.

4. The apparatus for forming a sealing resin according to any one of claims 1 to 3, characterized in that, Powdered resin is used as the base resin.

5. The apparatus for forming a sealing resin according to any one of claims 1 to 3, characterized in that... include: The lower mold film supply unit supplies and adheres the release film to the mold surface of the lower mold; and the upper mold film supply unit supplies and adheres the release film to the mold surface of the upper mold.

6. A method for forming a sealing resin, comprising compressing a base resin into sheets to form a sealing resin for compression molding of a workpiece. The method for forming the sealing resin is characterized by including a tableting process. In the tableting process, a predetermined amount of the base resin is contained in a tableting mold and pressed into a tablet to form the sealing resin having a predetermined shape corresponding to the shape of the workpiece.

7. The method for forming the sealing resin according to claim 6, characterized in that, The workpiece used is one having a structure in which electronic components are mounted on a substrate. The specified shape is the shape in which the sealing resin does not come into contact with the electronic component when it is placed on the substrate.

8. The method for forming the sealing resin according to claim 7, characterized in that, The workpiece used is one having a structure in which electronic components are mounted on a substrate. The method for forming the sealing resin includes a resin amount setting step, in which, for each workpiece, the number of electronic components mounted on a substrate is measured and the required amount of resin is calculated to set the specified amount, or the specified amount is selected and set from a variety of fixed amounts corresponding to the type of workpiece.

9. The method for forming the sealing resin according to any one of claims 6 to 8, characterized in that, Powdered resin is used as the base resin.

10. The method for forming the sealing resin according to any one of claims 6 to 8, characterized in that, The tableting process is carried out at a temperature at which the base resin will not heat-cur, so that the resulting sealing resin can be heat-cured in a subsequent resin sealing process.

11. The method for forming the sealing resin according to any one of claims 6 to 8, characterized in that, The process prior to the tableting process includes: a lower mold film supply process, in which a release film is supplied and adsorbed onto the mold surface of the lower mold; and an upper mold film supply process, in which a release film is supplied and adsorbed onto the mold surface of the upper mold.

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