Apparatus and method for forming sealing resin used in compression molding

Abstract

To provide a compression molding apparatus and a method for forming a sealing resin, which can realize a compression molding apparatus and a compression molding method capable of preventing the occurrence of molding defects.SOLUTION: A sealing resin forming apparatus 100 according to the present invention is a forming apparatus that tablets a base resin Rm to form a sealing resin R to be used for compression molding of a workpiece W, and is equipped with a tableting mold 102 that holds a predetermined amount of base resin Rm in one or both of a pair of a lower mold 106 and an upper mold 104 that are opened and closed, and tablets the base resin R to form a sealing resin R having a predetermined shape corresponding to the shape of the workpiece W.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present invention relates to a forming apparatus and a forming method for a sealing resin used in compression molding.

Background Art

[0002] As an example of a resin sealing apparatus and a resin sealing method for sealing a work in which an electronic component is mounted on a base material with a sealing resin and processing it into a molded product, a compression molding method is known.

[0003] The compression molding method is a technique for resin sealing by supplying a predetermined amount of sealing resin to a sealing region (cavity) provided in a sealing mold including an upper mold and a lower mold, arranging a work in the sealing region, and clamping with the upper mold and the lower mold. As an example, when using a sealing mold provided with a cavity in the upper mold, a technique of supplying and molding the sealing resin all at once at the center position on the work is known. On the other hand, when using a sealing mold provided with a cavity in the lower mold, a technique of supplying a release film (hereinafter sometimes simply referred to as "film") covering the mold surface including the cavity and the sealing resin and molding is known (see Patent Document 1: JP-A-2019-145550).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] For example, when resin encapsulating strip-type wire-connected electronic components (semiconductor chips) as a workpiece, a compression molding method in which a cavity is provided in the upper mold presents a problem: the wire portion of the workpiece held in the lower mold comes into contact with the encapsulating resin supplied to the cavity beforehand or to the workpiece, causing deformation and making resin encapsulation difficult. Therefore, a compression molding method has generally been adopted in which the workpiece is held in the upper mold, a cavity is provided in the lower mold, and the encapsulating resin (for example, granular resin) is supplied into the cavity.

[0006] However, in a configuration where the workpiece is held in the upper mold and a cavity is provided in the lower mold, there was a problem that when the workpiece was thin or large, it was difficult to hold it in the upper mold and it was prone to falling. Also, although the sealing resin is usually supplied into the cavity of the lower mold via a film, when trying to form a molded product that is thicker than about 1 mm (in this case, the thickness of the resin part after molding), the molding stroke becomes large, and there was a problem that molding defects such as the film getting caught in the molded product were likely to occur. Furthermore, when granular resin is used as the sealing resin, the aforementioned film getting caught is more likely to occur, and in addition to the problems of dust generation and difficulty in handling, it is difficult to supply (dispense) the sealing resin evenly to the entire area of ​​the cavity provided in the lower mold. Sprinkling There was a problem with unevenness in the encapsulation process. Furthermore, during the application of the encapsulating resin, air trapped in the gaps between particles, and gaseous components resulting from degassing during melting, were prone to remaining in the molded product, leading to molding defects. In particular, in workpieces with electronic components mounted via wire connections, there was a risk of wire flow (deformation and breakage of the wires) occurring due to resin flow within the cavity during resin encapsulation. [Means for solving the problem]

[0007] The present invention has been made in view of the above circumstances, and provides a sealing resin that is easy to handle, and solves the problems of a configuration in which a cavity is provided in the upper mold and a configuration in which a cavity is provided in the lower mold, and the resin flow, Sprinkling The objective is to provide a compression molding apparatus and method for forming a sealing resin that enables the formation of a large-thickness molded product while preventing molding defects caused by uneven molding, residual gas, and dust generation during molding.

[0008] The present invention solves the above problem by a solution described below as one embodiment.

[0009] An apparatus for forming a sealing resin according to one embodiment is a forming apparatus for forming a sealing resin used for compression molding of a workpiece by compressing a base resin into tablets, and is required to include a tableting 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 compresses the resin into tablets having a predetermined shape corresponding to the shape of the workpiece. For example, the workpiece used is a workpiece having an electronic component mounted on a base material.

[0010] Furthermore, it is preferable to include a lower mold film supply unit that supplies a release film to be adsorbed onto the mold surface of the lower mold, and an upper mold film supply unit that supplies a release film to be adsorbed onto the mold surface of the upper mold.

[0011] Furthermore, with respect to the workpiece, the predetermined shape is preferably such that the sealing resin does not come into contact with the electronic components when placed on the substrate, and the predetermined amount is preferably such that the amount of resin required is calculated by measuring the number of electronic components present or absent on a single substrate for each workpiece, or is set by selecting from a plurality of standard amounts corresponding to the type of workpiece.

[0012] Furthermore, it is preferable that a powder resin be used for the base resin.

[0013] Furthermore, a method for forming a sealing resin according to one embodiment is a method for forming a sealing resin used for compression molding of a workpiece by compressing a base resin into tablets, and is required to include a tableting step in which a predetermined amount of the base resin is placed in a tableting mold and compressed into tablets to form a sealing resin having a predetermined shape corresponding to the shape of the workpiece. [Effects of the Invention]

[0014] By using the sealing resin formed by the forming apparatus and forming method according to the present invention, the problems of a configuration in which a cavity is provided in the upper mold and a configuration in which a cavity is provided in the lower mold are solved, and the resin flow is improved. Sprinkling This compression molding apparatus and method can be realized that prevent molding defects caused by uneven molding, residual gas, and dust generation during molding, and enable the formation of molded products with large thickness dimensions. Furthermore, handling is easier, especially during supply and setup, compared to granular resins and the like. [Brief explanation of the drawing]

[0015] [Figure 1] This is a plan view showing an example of a compression molding apparatus that uses a sealing resin formed by an embodiment of the present invention. [Figure 2] This is an explanatory diagram illustrating an example of a compression molding method using a sealing resin formed by a forming apparatus and forming method according to an embodiment of the present invention. [Figure 3] This is an explanatory diagram following Figure 2. [Figure 4] This is an explanatory diagram following Figure 3. [Figure 5] This is an explanatory diagram illustrating another example of a compression molding method using a sealing resin formed by a forming apparatus and forming method according to an embodiment of the present invention. [Figure 6] This is an explanatory diagram following Figure 5. [Figure 7] This is an explanatory diagram following Figure 6. [Figure 8] This is a side view showing an example of a sealing resin forming apparatus according to an embodiment of the present invention. [Figure 9]It is a front sectional view showing an example of an ingot mold of a forming apparatus shown in FIG. 8. [Figure 10] It is an explanatory view of a method for forming a sealing resin according to an embodiment of the present invention. [Figure 11] It is an explanatory view following FIG. 10. [Figure 12] It is an explanatory view following FIG. 11. [Figure 13] It is a perspective view showing an example of a sealing resin formed by a forming apparatus and a forming method according to an embodiment of the present invention. [Figure 14] It is a perspective view showing another example of a sealing resin formed by a forming apparatus and a forming method according to an embodiment of the present invention. [Figure 15] It is a perspective view showing another example of a sealing resin formed by a forming apparatus and a forming method according to an embodiment of the present invention. [Figure 16] It is a perspective view showing another example of a sealing resin formed by a forming apparatus and a forming method according to an embodiment of the present invention. [Figure 17] FIG. 17A is an enlarged view of part A in FIG. 2. FIG. 17B is an explanatory view following FIG. 17A. [Figure 18] It is an explanatory view of a conventional compression molding method. [Figure 19] It is an explanatory view of a conventional compression molding method. [Figure 20] It is a front sectional view showing another example of an ingot mold of a forming apparatus according to an embodiment of the present invention.

Embodiments for Carrying Out the Invention

[0016] (Compression Molding Apparatus and Compression Molding Method) A sealing resin forming apparatus and a forming method according to an embodiment of the present invention are an apparatus and a method for forming a sealing resin R used for compression molding of a work W. First, an outline of a compression molding apparatus 1 and a compression molding method for performing resin sealing (compression molding) of a work W using the sealing resin R will be described. Here, FIG. 1 is a plan view (schematic view) showing an example of the compression molding apparatus 1.

[0017] The workpiece W to be sealed has a configuration in which electronic components Wb are mounted on a substrate Wa. More specifically, examples of substrate Wa include plate-shaped members such as resin substrates, ceramic substrates, metal substrates, carrier plates, lead frames, and wafers. Examples of electronic components Wb include semiconductor chips, MEMS chips, passive elements, heat sinks, conductive members, and spacers. The shape of the substrate Wa can be rectangular (strip-shaped), square, circular, etc. The number of electronic components Wb mounted on a single substrate Wa can be one or multiple (for example, in a matrix).

[0018] Examples of methods for mounting electronic components Wb onto a substrate Wa include wire bonding and flip-chip mounting. Alternatively, in configurations where the substrate (glass or metal carrier plate) Wa is peeled off the molded product Wp after resin encapsulation, the electronic components Wb can be attached using heat-release adhesive tape or UV-curable resin that hardens upon UV irradiation.

[0019] Furthermore, suitable examples of film F include film materials with excellent heat resistance, ease of peeling, flexibility, and stretchability, such as PTFE (polytetrafluoroethylene), ETFE (polytetrafluoroethylene polymer), PET, FEP, fluorine-impregnated glass cloth, polypropylene, and polyvinylidine chloride. Film F is also used when forming the sealing resin R in the forming apparatus 100 described later.

[0020] As shown in Figure 1, the compression molding apparatus 1 mainly comprises a supply unit 10A for supplying workpieces W, a press unit 10B for processing workpieces W into molded products Wp by resin encapsulation, and a storage unit 10C for storing the molded products Wp. As an example, the supply unit 10A, press unit 10B, and storage unit 10C are arranged in that order along the X direction in Figure 1. However, the configuration is not limited to the above, and the equipment configuration within the units, the number of units (especially the number of press units), and the arrangement order of the units can be changed. It is also possible to have a configuration with units other than those shown above (none of which are shown).

[0021] Furthermore, the compression molding apparatus 1 has a guide rail 20 provided in a straight line spanning between each unit, and a transport device (first loader) 22 for transporting the workpiece W and the sealing resin R, and a transport device (second loader) 24 for transporting the molded product Wp (which may also be used for transporting the sealing resin R) are provided to move along the guide rail 20 between predetermined units. However, the configuration is not limited to the above, and a configuration with a common (single) transport device (loader) for transporting the workpiece W, the sealing resin R, and the molded product Wp is also possible (not shown). In addition, the transport device may be configured to include a robot hand or the like instead of a loader.

[0022] Furthermore, the compression molding apparatus 1 has a control unit 30 located in the supply unit 10A that controls the operation of each mechanism in each unit (it may also be configured to have the control unit 30 located in another unit).

[0023] The press unit 10B is equipped with a pair of sealing dies that are opened and closed by the press device 250. The sealing dies may, for example, be configured such that a cavity is provided in the upper die (sealing die 202), or as another example, the cavity may be provided in the lower die (sealing die 302). The press device 250 is also equipped with a film supply unit 211 that supplies a film F to cover the die surface 204a (a predetermined area) including the inner surface of the cavity 208 in the upper die 204. For example, the film F may be in the form of a roll, but it may also be in the form of strips.

[0024] As an example, the steps of a compression molding method performed using a compression molding apparatus 1 equipped with a sealing mold 202 will be explained with reference to Figures 2 to 4.

[0025] First, a preparation process (sealing preparation process) is carried out. Specifically, the upper mold 204 and the lower mold 206 are heated to a predetermined temperature (for example, 100°C to 300°C). In addition, the film supply unit 211 is activated to supply a new film F, which is then adsorbed to cover a predetermined area of ​​the mold surface 204a, including the inner surface of the cavity 208 in the upper mold 204.

[0026] After the preparation process, a workpiece holding process is performed in which the workpiece W is held in the workpiece holding section 205 of the lower mold 206. Specifically, the workpiece W supplied from the supply magazine 12 is held by the first loader 22 and transported into the sealing mold 202, where it is held in the workpiece holding section 205 of the lower plate 242 (mold surface 206a).

[0027] After the workpiece holding process, a resin placement process is performed in which the sealing resin R is placed on top of the workpiece W held in the workpiece holding section 205 (see Figure 2). Specifically, the sealing resin R formed in the sealing resin forming apparatus (sometimes simply referred to as the "forming apparatus") 100, which will be described later, is held by the first loader 22 (other conveying devices may also be used) and transported into the sealing mold 202, where it is placed on top of the workpiece W held in the workpiece holding section 205.

[0028] Alternatively, as another example of the resin placement process, it may be performed as a step in which the sealing resin R formed in the forming apparatus 100 is placed on the workpiece W before the workpiece holding process described above. In that case, the workpiece holding process becomes a process of holding the workpiece W with the sealing resin R placed on it in the workpiece holding section 205. That is, the first loader 22 holds the workpiece W with the sealing resin R placed on it and transports it into the sealing mold 202, where it is held in the workpiece holding section 205. This has the advantage of performing the process of placing the workpiece W and sealing resin R into the sealing mold 202 in one step, rather than separately.

[0029] Next, a resin sealing process is carried out to seal the workpiece W with sealing resin R and process it into a molded product Wp. Specifically, the sealing mold 202 is closed, and the cavity piece 226 is lowered relative to the workpiece W within the cavity 208 surrounded by clamper 228, thereby performing a mold closing process in which the sealing resin R is heated and pressurized. As a result, the sealing resin R is heat-cured and the resin sealing (compression molding) is completed (see Figure 3).

[0030] The subsequent steps following the mold closing process described above are the same as those in conventional compression molding methods. In general, a mold opening process is performed in which the sealing mold 202 is opened to separate the molded product Wp from the used film F and allow the molded product Wp to be removed (see Figure 4). Next, a molded product removal process is performed in which the second loader 24 unloads the molded product Wp from inside the sealing mold 202 and transports it to the storage unit 10C. As an example, the transported molded product Wp is stored in the storage magazine 14. After the molded product removal process, or in parallel with it, a film supply unit 211 is activated to send the used film F out of the sealing mold 202 and feed a new film F into the sealing mold 202 and set it in place.

[0031] The above outlines the main steps of the compression molding method performed using the compression molding apparatus 1 equipped with a sealing mold 202. However, the above order of steps is merely an example, and the order can be changed or the steps performed in parallel as long as there are no obstacles.

[0032] As another example, the steps of a compression molding method performed using a compression molding apparatus 1 equipped with a sealing die 302 will be described with reference to Figures 5 to 7. In this case, the press apparatus 250 is provided with a film supply unit 311 that supplies a film F to cover the mold surface 306a (a predetermined area) including the inner surface of the cavity 308 in the lower mold 306. For example, the film F is in the form of a roll, but it may also be in the form of strips.

[0033] First, a preparation process (sealing preparation process) is carried out. Specifically, the upper mold 304 and the lower mold 306 are heated to a predetermined temperature (for example, 100°C to 300°C). In addition, the film supply unit 311 is activated to supply a new film F, which is then adsorbed to cover a predetermined area of ​​the mold surface 306a, including the inner surface of the cavity 308 in the lower mold 306.

[0034] After the preparation process, a workpiece holding process is performed in which the workpiece W is held in the workpiece holding section 305 of the upper mold 304. Specifically, the workpiece W supplied from the supply magazine 12 is held by the first loader 22 and transported into the sealing mold 302, where it is held in the workpiece holding section 305 of the upper plate 342 (mold surface 304a).

[0035] The resin holding process is performed after the workpiece holding process (however, it may be performed before or in parallel with the workpiece holding process). The resin holding process has the following steps: The sealing resin R is held in the cavity 308 of the lower mold 306 (see Figure 5). Specifically, the sealing resin R formed in the forming apparatus 100 is held by the first loader 22 (other conveying devices may also be used) and transported into the sealing mold 302 and placed in the cavity 308 (specifically, it is placed on the upper surface of the cavity piece 326).

[0036] Next, a resin sealing process is performed in which the workpiece W is sealed with a sealing resin R to form a molded product Wp. Specifically, the sealing mold 302 is closed, and the cavity piece 326 is raised relative to the workpiece W within the cavity 308 surrounded by the clamper 328, thereby performing a mold closing process in which the sealing resin R is heated and pressurized. As a result, the sealing resin R is heat-cured and the resin sealing (compression molding) is completed (see Figure 6).

[0037] The subsequent steps following the mold closing process described above are the same as those in conventional compression molding methods. In general, a mold opening process is performed in which the sealing mold 302 is opened to separate the molded product Wp from the used film F and allow the molded product Wp to be removed (see Figure 7). Next, a molded product removal process is performed in which the molded product Wp is unloaded from the sealing mold 302 by the second loader 24 and transported to the storage unit 10C. As an example, the transported molded product Wp is stored in the storage magazine 14. After the molded product removal process, or in parallel therewith, a film supply unit 311 is activated to send the used film F out of the sealing mold 302 and feed a new film F into the sealing mold 302 and set it in place.

[0038] The above describes the main steps of the compression molding method performed using the compression molding apparatus 1 equipped with a sealing die 302. However, the above order of steps is just one example, and the order can be changed or the steps performed in parallel as long as there are no problems.

[0039] (Sealing resin forming apparatus) Next, the forming apparatus 100 for forming the sealing resin R used in the above-described compression molding apparatus 1 and compression molding method will be described with reference to Figures 8 and 9. The forming apparatus 100 processes the base resin Rm to form the sealing resin R. Here, Figure 8 is a side view (schematic diagram) showing an example of the forming apparatus 100. The forming apparatus 100 may be installed either inside or outside the compression molding apparatus 1.

[0040] In this embodiment, a thermosetting resin (for example, an epoxy resin containing a filler, but not limited to this) is used as the base resin Rm and the sealing resin R formed from the base resin Rm. The sealing resin R is formed as a solid or semi-solid resin having a predetermined shape (details described later) whose overall shape corresponds to the shape of the workpiece W. Normally, one piece constitutes the "whole" amount required for sealing (one batch per workpiece W), but it may also be configured so that several pieces (for example, two or three pieces) constitute the "whole" amount required for sealing. Furthermore, the "semi-solid" mentioned above refers not to a completely solid state but to a state that has melted to the so-called B stage. In addition, a powder resin (form) that is a thermosetting resin (properties) is preferably used as the base resin Rm (details described later). However, it is not limited to this, and a granular resin, crushed resin, solid resin, liquid resin, or a resin combining several of these may be used.

[0041] As shown in Figure 8, the forming apparatus 100 includes a tablet press die 102 having a pair of molds that are opened and closed (for example, a die assembled from multiple die blocks, die plates, die pillars, and other components made of alloy tool steel). It also includes a press device 150 that drives the tablet press die 102 to open and close. Here, Figure 9 is a front cross-sectional view (schematic diagram) showing an example of the tablet press die 102.

[0042] As shown in Figure 8, the press device 150 is configured to include a pair of platens 154 and 156, a plurality of tie bars 152 on which the pair of platens 154 and 156 are mounted, and a drive device for moving (raising and lowering) the platen 156. Specifically, the drive device is configured to include a drive source (e.g., an electric motor) 160 and a drive transmission mechanism (e.g., a ball screw or a toggle link mechanism) 162, etc. (however, it is not limited to this). In this embodiment, the upper platen 154 in the vertical direction is set as a fixed platen (a platen fixed to the tie bar 152), and the lower platen 156 is set as a movable platen (a platen that is slidably held by the tie bar 152 and moves up and down). However, it is not limited to this, and the top and bottom may be reversed, that is, the upper side may be set as a movable platen and the lower side as a fixed platen, or both the upper and lower sides may be set as movable platens (none of which are shown).

[0043] On the other hand, as shown in Figure 9, the tablet press die 102 comprises an upper die 104 on the upper side in the vertical direction and a lower die 106 on the lower side, as a pair of dies arranged between the pair of platens 154 and 156 in the press device 150. The upper die 104 is assembled to the upper platen (fixed platen 154 in this embodiment), and the lower die 106 is assembled to the lower platen (movable platen 156 in this embodiment). The die is closed and opened by the upper die 104 and the lower die 106 moving closer to and further apart from each other (the vertical direction (up and down direction) is the die opening and closing direction). In the tablet press die 102 according to this embodiment, the upper die 104 constitutes a so-called "punch die," and the lower die 106 constitutes a so-called "die die."

[0044] Next, the lower die 106 of the tablet press mold 102 will be described in detail. As shown in Figure 9, the lower die 106 comprises a lower die chase 110 and a cavity piece 126, a clamper 128, etc., held by it. The lower die chase 110 is fixed to the upper surface of the support plate 114 via a support pillar 112. A cavity 108 is provided on the upper surface of the lower die 106 (the surface on the upper die 104 side). A predetermined amount of base resin Rm is contained within this cavity 108.

[0045] The clamper 128 is configured in an annular shape to surround the cavity die 126 and is assembled to move vertically while floating away from the upper surface of the support plate 114 via a push pin 122 and a clamper spring 124 (for example, a biasing member exemplified by a coil spring) (however, it is not limited to this assembly structure). The cavity die 126 constitutes the back (bottom) of the cavity 108, and the clamper 128 constitutes the side of the cavity 108. The shape and number of cavities 108 provided in one lower die 106 are set as appropriate (one or more).

[0046] Here, the press device 150 is provided with a lower die film supply unit 111 that supplies a film F to cover the die surface 106a (a predetermined area) including the inner surface of the cavity 108 in the lower die 106. For example, the film F is in the form of a roll, but it may also be in the form of strips.

[0047] Furthermore, the lower mold 106 is provided with suction passages (holes, grooves, etc.) that communicate with a suction device on the upper surface of the clamper 128 and at the boundary between the clamper 128 and the cavity die 126 (not shown). This allows the film F supplied from the lower mold film supply unit 111 to be adsorbed and held on the mold surface 106a, including the inner surface of the cavity 108.

[0048] Furthermore, in this embodiment, a lower mold heating mechanism (not shown) is provided to heat the lower mold 106 to a predetermined temperature. This 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 chase 110 and is configured to apply heat to the entire lower mold 106 and the base resin Rm contained in the cavity 108. At this time, the lower mold 106 is heated to a predetermined temperature (e.g., 50°C to 80°C) such that the base resin Rm does not undergo thermal curing (full curing).

[0049] Next, the upper die 104 of the tableting die 102 will be described in detail. As shown in Figure 9, the upper die 104 includes a tableting plate 142 that presses a predetermined amount of base resin Rm contained in the cavity 108 of the lower die 106 to form (tablet) a sealing resin R having a predetermined shape corresponding to the shape of the workpiece W (details of the forming method will be described later). The tableting plate 142 is held (fixed) in the upper die chase 140. As an example, a leg-forming groove (including a recess) 143 for forming the leg portion Rb of the sealing resin R is provided on the lower surface (the surface on the lower die 106 side) of the tableting plate 142.

[0050] Here, the press device 150 is provided with an upper die film supply unit 113 that supplies a film F to cover the die surface 104a (a predetermined area) of the upper die 104. For example, the film F is in the form of a roll, but it may also be in the form of strips.

[0051] Furthermore, the upper mold 104 is provided with a suction passage (hole or groove, etc.) in the tablet pressing plate 142, etc., which communicates with a suction device (not shown). This allows the film F supplied from the upper mold film supply unit 113 to be adsorbed onto the mold surface 104a and held in place.

[0052] Furthermore, in this embodiment, an upper mold heating mechanism (not shown) is provided to heat the upper mold 104 to a predetermined temperature. This 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 the control unit 30. For example, the heater is built into the upper mold chase 140 and is configured to apply 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) such that the base resin Rm held (housed) in the lower mold 106 does not undergo thermal curing (full curing).

[0053] (Method for forming encapsulating resin) Next, the steps of the method for forming the sealing resin according to this embodiment, which is carried out using the forming apparatus 100 described above, will be explained. Here, Figures 10 to 12 are explanatory diagrams of each step, and are shown as front cross-sectional views in the same direction as Figure 9.

[0054] First, a preparation process (tablet preparation process) is carried out. The preparation process consists of the following steps: A lower mold heating process is carried out in which the lower mold 106 is heated to a predetermined temperature (a temperature at which the base resin Rm and sealing resin R do not fully harden, for example, 50°C to 80°C) using a lower mold heating mechanism. An upper mold heating process is carried out in which the upper mold 104 is heated to a predetermined temperature (a temperature at which the base resin Rm and sealing resin R do not fully harden, for example, 50°C to 80°C) using an upper mold heating mechanism. A lower mold film supply process is carried out in which a new film F is supplied by operating the lower mold film supply unit 111 and adsorbed to cover a predetermined area of ​​the mold surface 106a, including the inner surface of the cavity 108 in the lower mold 106. An upper mold film supply process is carried out in which a new film F is supplied by operating the upper mold film supply unit 113 and adsorbed to cover a predetermined area of ​​the mold surface 104a of the upper mold 104.

[0055] After the preparation process, a tableting process is carried out to form a solid or semi-solid resin as a sealing resin R, which has a predetermined shape (described later) whose overall shape corresponds to the shape of the workpiece W, by tableting the base resin Rm. Specifically, a predetermined amount of base resin Rm is contained in the cavity 108 of the lower mold 106 using a dispenser or the like (see Figure 10). Next, the press device 150 is operated to close the tableting mold 102, which has been heated to the predetermined temperature (see Figure 11). At this time, the cavity piece 126 rises relatively within the cavity 108, and the base resin Rm is tableted (pressurized by being sandwiched) between the cavity piece 126 and the tableting plate 142. As a result, a solid or semi-solid sealing resin R having a predetermined shape and in a state that has not yet undergone heat curing (full curing) is formed. At this time, the base resin Rm that enters the leg-forming groove 143 of the tablet plate 142 via the film F becomes the leg Rb of the sealing resin R, and the remaining base resin Rm becomes the main body Ra of the sealing resin R (the detailed configuration of the sealing resin R will be described later). As a variation of the tableting process, a portion of a predetermined amount of base resin Rm may be held (welded, gripped, etc.) in the upper die 104 (not shown). In addition, although the leg-forming groove 143 is provided in the tablet plate 142, it may also be provided in the cavity die 126, or in both.

[0056] The tableting process described above is important to be carried out at a temperature at which the base resin Rm does not heat-cur (mainly harden), so that the formed sealing resin R can be heat-cured (mainly hardened) in the subsequent resin sealing process (which is a compression molding process). This is achieved by heating the lower mold 106 and upper mold 104 to a temperature at which the base resin Rm does not heat-cur (mainly harden). As mentioned above, the "temperature at which the base resin Rm does not heat-cur" depends on the material of the base resin Rm, but as a specific example, it is about 50°C to 80°C (in this embodiment, it is about 70°C).

[0057] Here, the "predetermined shape" of the sealing resin R will be explained. As an example, in the case of a sealing resin R used in a compression molding apparatus 1 equipped with a sealing mold 202, the "predetermined shape" is a shape that does not come into contact with the electronic component Wb (including the wire if the electronic component Wb has a wire) when placed on the base material Wa of the workpiece W. As an example, as shown in Figure 2, a sealing resin R with a plate-shaped or block-shaped main body Ra and legs Rb intermittently (or continuously) erected on one surface of the main body Ra (the surface of the workpiece W facing the electronic component Wb) is preferred (however, it is not limited to this shape). The main body Ra is sized to fit inside the cavity 208 in a plan view, and considering resin flow, it is preferable that it be slightly smaller than the shape of the cavity 208 (especially the cavity block 226). In addition, the legs Rb need to have a height H (see Figure 17A) that does not come into contact with the electronic component Wb, but this does not exclude contact to the extent that the wire does not undergo plastic deformation. Furthermore, the legs Rb are positioned so as not to contact the electronic components Wb in a plan view of the main body Ra, and so as not to tilt the main body Ra when placed on the base material Wa of the workpiece W. In addition, it is preferable that the legs Rb be positioned between or around the electronic components Wb to minimize damage to the wiring (especially wires) of the workpiece W during molding. The total amount of resin for the plate-shaped or block-shaped main body Ra and the legs Rb may be an amount that is neither too much nor too little, or a large amount of resin, so as not to be insufficient for a single compression molding. Specific examples of the encapsulating resin R configuration (Figures 13 to 16) will be described later.

[0058] As another example, in the case of a sealing resin R used in a compression molding apparatus 1 equipped with a sealing mold 302, the "predetermined shape" is such that, when closing the sealing mold 302, the upper mold 304 is gradually brought closer to the lower mold 306, and the tip (upper end) of the leg portion Rb of the sealing resin R housed in the cavity 308 comes into contact with the base material Wa of the workpiece W held by the workpiece holding portion 305, the main body portion Ra of the sealing resin R does not come into contact with the electronic component Wb of the workpiece W (including the wire if the electronic component Wb has a wire). The specific shape of the sealing resin R is the same as in the case of a sealing resin R used in a compression molding apparatus 1 equipped with a sealing mold 202 (see Figures 17A, 13-16), so repeated explanations are omitted. However, the sealing resin R is not limited to the configuration shown in Figures 17A, 13-16, and may have a configuration in which the upper surface is formed in a flat shape without providing the leg portion Rb on the upper surface (not shown).

[0059] Next, the resin quantity setting process for setting the "determined amount" of the base resin Rm described above will be explained. As an example of the resin quantity setting process, for each workpiece W to be sealed, the number of electronic components Wb mounted on a single substrate Wa (the number mounted or the number missing, and may also include measuring the height of the electronic components Wb) is measured by a measuring mechanism (not shown), and the control unit 30 calculates the amount of resin (in grams) required for resin sealing (compression molding) by subtracting the total volume of electronic components Wb from the volume of the cavities 208 and 308 of the sealing molds 202 and 302, and sets the "determined amount". Alternatively, as another example of the resin quantity setting process, multiple standard quantities corresponding to the type of workpiece W to be sealed are prepared, and the control unit 30 or the operator selects the optimal one from these standard quantities according to the type of workpiece W to set the "determined amount". In the case of standard quantities, it is important that there is no shortage of resin during resin sealing (compression molding). In either setting, an appropriate amount of base resin Rm can be supplied to the workpiece W. Therefore, it is possible to prevent molding defects caused by insufficient resin during resin encapsulation. Furthermore, it is possible to prevent waste caused by supplying more resin than necessary.

[0060] Furthermore, it is preferable to use powder resin as the base resin Rm. This allows for extremely precise adjustment and supply of a "determined amount" of resin compared to cases where granular resin or crushed resin is used. However, it is not limited to powder resin.

[0061] After the tableting process, the tableting mold 102 is opened to separate the sealing resin R from the used film F and to allow the sealing resin R to be removed (see Figure 12). In this embodiment, by including the aforementioned lower mold film supply process and upper mold film supply process, the film F is placed on both the mold surface 106a of the lower mold 106 and the mold surface 104a of the upper mold 104. This makes it easy to release the sealing resin R formed by tableting and prevents defects caused by resin adhesion to the mold.

[0062] After the die opening process, or concurrently therewith, the lower die film supply unit 111 and the upper die film supply unit 113 are activated to expel the used film F from inside the tablet mold 102 and to feed and set a new film F into the tablet mold 102 in a film supply process (lower die film supply process, upper die film supply process).

[0063] (Sealing resin) Next, Figures 13 to 16 show specific examples of the configuration of the sealing resin R formed by the above-described forming apparatus and forming method, and their respective characteristics will be explained.

[0064] First, as a configuration common to each example shown in FIGS. 13 to 16, the main body portion Ra is formed in a plate shape (note that it may also be in a shape other than a plate shape, such as a block shape having concave portions, convex portions, etc.). Further, the leg portion Rb is erected on the main body portion Ra so that when the sealing resin R is placed at a predetermined position (set position in design) on the base material Wa of the work W, it does not contact the electronic component Wb of the work W, and is formed to a height H (see FIG. 17A) that can ensure a distance at which the main body portion Ra does not contact the electronic component Wb. As described above, in the tableting process, the base resin Rm that enters the leg formation groove 143 of the tableting plate 142 through the film F becomes the leg portion Rb of the sealing resin R, and the other (remaining) base resin Rm becomes the main body portion Ra of the sealing resin R.

[0065] In the example of the sealing resin R shown in FIG. 13, the leg portion Rb is formed as a convex body Rb1 that is entirely (or partially) arranged in a dot shape. As an example of the convex body Rb1, it is arranged at a plurality of positions, and the ratio t of the length L1 to the width W1 in a plan view is formed in a shape such that, for example, 0.5 ≦ t ≦ 2. According to this, the configuration in which the leg portion Rb is a columnar shape arranged in a dot shape can suppress the flow of the sealing resin R placed on the work W during compression molding. Therefore, wire flow and the like can be prevented, and the molding quality can be improved.

[0066] In the example of the sealing resin R shown in FIG. 14, the leg portion Rb is formed as a convex body Rb2 that is partially (or entirely) arranged in a linear shape. As an example of the convex body Rb2, it is arranged at one position (or a plurality of positions), and the ratio t of the length L2 to the width W2 in a plan view is formed in a shape such that, for example, t < 0.5 or 2 < t. According to this, resin flow can be intentionally generated from the leg portion Rb (in this case, the convex body Rb2) having a dike-like configuration of a predetermined length, and the filling of the sealing resin R into a narrow portion (for example, between the base material Wa to which a flip chip is connected and the electronic component Wb) in the work W can be promoted. Therefore, it is possible to prevent gas from remaining in the molded product Wp, and the molding quality can be improved.

[0067] In the example of the sealing resin R shown in Figure 15, the leg portion Rb is formed as a convex body Rb3 that intermittently (or continuously) surrounds the entire outer circumference (referring to the outer edge region) of the main body portion Ra. As an example of the convex body Rb3, convex bodies with the same configuration as Rb2 described above are formed in a continuous manner around the circumference, with gaps L3 provided at predetermined intervals. Generally, the outer circumference of the sealing resin R in the molded product Wp is the position where it is cut by a dicer or the like when it is made into individual pieces, and since there are no electronic components Wb there, it requires a larger amount of resin to seal compared to the central position. Therefore, by providing leg portions Rb (in this case, convex body Rb3) that surround the entire outer circumference as in this configuration, it is possible to supply a large amount of resin to the outer circumference while suppressing resin flow during compression molding. Furthermore, the provision of gaps L3 promotes the discharge of gaseous components such as air from the inside (central part) to the outside.

[0068] On the other hand, the example of the sealing resin R shown in Figure 16 is a configuration example relating to the other surface of the main body Ra (the surface on which the leg portion Rb is not provided, i.e., the surface on which the workpiece W does not face the electronic component Wb). Specifically, on the other surface of the main body Ra, linear groove portions Rg are formed at the positions where dicing for individual piece formation is performed. This reduces wear on the dicing blade and reduces dust generated during dicing. As an example, the groove portions Rg are provided in a grid pattern that coincides with the dicing positions, but this is not the only option. In order to form the groove portions Rg, the tableting process can be carried out using a cavity die 126 on which a correspondingly shaped projection (not shown) is provided on the upper surface.

[0069] As described above, by using the sealing resin R formed by the forming apparatus and forming method according to the present invention, a compression molding apparatus and compression molding method can be realized that provide the following effects. Specifically, the compression molding apparatus and compression molding method enable resin flow, SprinklingThis system prevents molding defects caused by uneven molding, residual gas, and dust generation during molding. Furthermore, it can form not only thin molded products (Wp) with a thickness of less than 1 mm, but also thick molded products (Wp) with a thickness of 1 mm or more. While the upper limit of the thickness depends on various setting conditions, it is considered possible to form products up to approximately 10 mm thick. Additionally, handling during supply and setup is facilitated.

[0070] Furthermore, the compression molding apparatus and method described herein can solve the problems that arise when a cavity is provided in the upper mold. Specifically, in conventional compression molding apparatuses where a cavity is provided in the upper mold, for example, when performing a mold closing process on a workpiece W on which a strip-type wire-connected electronic component (semiconductor chip) Wb is mounted, the wire portion of the workpiece held in the lower mold comes into contact with the sealing resin supplied to the cavity beforehand or the sealing resin supplied onto the workpiece, causing deformation and cutting, which makes resin sealing difficult. This problem can be solved by adopting a configuration in which the sealing resin R formed by the apparatus and method according to this embodiment is a solid or semi-solid resin formed into a predetermined shape corresponding to the shape of the workpiece W.

[0071] Specifically, during the mold closing process, the sealing resin R softens and melts due to heating, as shown in Figure 17A to Figure 17B (Figures 17A and 17B are enlarged views of section A in Figure 2). At this time, the resin (specifically, the main body Ra) comes into uniform contact with all the wires (see Figure 17B). Therefore, deformation and breakage of the wires can be prevented.

[0072] Furthermore, when the inventor of the present invention actually conducted experiments using the above-described compression molding apparatus 1 with the sealing resin R formed by the apparatus and method according to this embodiment, it was confirmed that, compared to a conventional compression molding apparatus having a configuration in which the workpiece W is held in the upper mold, a cavity is provided in the lower mold, and sealing resin (specifically, granular resin) is supplied to the cavity, deformation and breakage of the wire were prevented and the molding quality was improved.

[0073] On the other hand, the compression molding apparatus and method described herein can also address the problems that arise when a cavity is provided in the lower mold. In other words, in conventional compression molding apparatuses where a cavity is provided in the lower mold, especially when granular resin is used as the sealing resin, the particle size and height (layer thickness) of the sealing resin (granular resin) contained in the cavity are not uniform. Therefore, for example, depending on the type and melting state of the granular resin, it may not be completely liquid (low viscosity), and when performing the mold closing process on a workpiece W on which a strip-type wire-connected electronic component (semiconductor chip) Wb is mounted, as shown in Figure 18, depending on the position, the wire portion of the workpiece held in the upper mold may come into strong (large) contact with the sealing resin (granular resin), causing deformation and cutting. Furthermore, as shown in Figure 19, there was a problem where a large amount of resin flow occurred in the cavity, causing deformation and cutting of the wire portion. This problem can be solved by adopting a configuration in which the sealing resin R formed by the apparatus and method according to this embodiment is a solid or semi-solid resin formed into a predetermined shape corresponding to the shape of the workpiece W.

[0074] Specifically, the reason is the same as explained in Figures 17A and 17B above: during the mold closing process, the sealing resin R softens and melts due to heating, resulting in uniform contact between all wires of the resin (specifically, the main body Ra). From this perspective, the sealing resin R is not limited to the configurations shown in Figures 13 to 16, and may have a configuration (not shown) where the top surface is flat without the legs Rb. This configuration also solves the problems caused by the non-uniformity of particle size and height (layer thickness) compared to conventional technology using granular resin. Furthermore, by making the sealing resin R forming apparatus 100 and the compression molding apparatus 1 separate devices, the compression molding apparatus 1 can be made unaffected by dust generated when compressing the powder resin in the forming apparatus 100, and the compression molding apparatus 1 can be easily placed in a clean room. Moreover, while the tableting mold 102 of the forming apparatus 100 has a movable clamper 128 as an example, it may also have a structure without a movable clamper, as shown in Figure 20.

[0075] Furthermore, the present invention is not limited to the embodiments described above, and can be modified in various ways without departing from the scope of the invention. [Explanation of Symbols]

[0076] 1. Compression molding apparatus 100 Apparatus for forming sealing resin 102 Tablet molds 142 Tablet Plates 202, 302 Sealing mold F Release Film Rm base resin R Sealing resin Ra main unit Rb leg Double job Wa base material Wb electronic components

Claims

1. A forming apparatus for compressing a base resin into tablets to form a sealing resin used for compression molding of a workpiece, A tableting mold is provided 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 a tablet so that it has a predetermined shape corresponding to the shape of the workpiece. As the aforementioned workpiece, a workpiece having a configuration in which electronic components are mounted on a substrate is used. The predetermined shape is such that the sealing resin does not come into contact with the electronic component when it is placed on the substrate. A sealing resin forming apparatus characterized by the following.

2. As the aforementioned workpiece, a workpiece having a configuration in which electronic components are mounted on a substrate is used. The predetermined amount is determined by measuring the number of electronic components mounted on each substrate for each workpiece and calculating the required amount of resin, or by selecting an amount from a plurality of standard amounts corresponding to the type of workpiece. The apparatus for forming a sealing resin according to claim 1, characterized by the above.

3. A powder resin is used as the base resin. An apparatus for forming a sealing resin according to claim 1 or claim 2, characterized by the above.

4. The system includes a lower mold film supply unit that supplies and adheres a release film to the mold surface of the lower mold, and an upper mold film supply unit that supplies and adheres a release film to the mold surface of the upper mold. An apparatus for forming a sealing resin according to claim 1 or claim 2, characterized by the above.

5. A method for forming a sealing resin used for compression molding of a workpiece, comprising compressing a base resin into tablets, The process includes a tableting step in which a predetermined amount of the base resin is placed in a tableting mold and compressed to form a sealing resin having a predetermined shape corresponding to the shape of the workpiece, As the aforementioned workpiece, a workpiece having a configuration in which electronic components are mounted on a substrate is used. The predetermined shape is such that the sealing resin does not come into contact with the electronic component when it is placed on the substrate. A method for forming a sealing resin characterized by the above.

6. As the aforementioned workpiece, a workpiece having a configuration in which electronic components are mounted on a substrate is used. The resin quantity setting step includes measuring the number of electronic components mounted on each of the aforementioned workpieces to determine the required amount of resin and set the predetermined amount, or selecting from a plurality of fixed quantities corresponding to the type of workpiece to set the predetermined amount. A method for forming a sealing resin according to claim 5, characterized by the above.

7. A powder resin is used as the base resin. A method for forming a sealing resin according to claim 5 or claim 6, characterized by the above.

8. The tableting process is carried out at a temperature at which the base resin does not heat-cur, so that the formed sealing resin can be heat-cured in a subsequent resin sealing process. A method for forming a sealing resin according to claim 5 or claim 6, characterized by the above.

9. Prior to the tableting process, the process includes a lower die film supply step in which a release film is supplied to the mold surface of the lower die and adhered to it, and an upper die film supply step in which a release film is supplied to the mold surface of the upper die and adhered to it. A method for forming a sealing resin according to claim 5 or claim 6, characterized by the above.

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