Resin molding apparatus and method for manufacturing resin molded articles

Abstract

This invention provides a resin molding apparatus with a simple structure to improve molding accuracy and a method for manufacturing resin molded articles. The resin molding apparatus includes: a molding die (C) holding a molded object on a substrate (11) on which a chip (13) is disposed, and having a cavity (MC) from which resin material (Ta) is supplied from a gate; a mold closing mechanism for closing the molding die (C); and a control unit (6) for controlling the operation of the molding die (6) and the mold closing mechanism. The molding die (C) includes: a movable block (16) for restricting at least a portion of the internal flow path of the cavity (MC) where the chip (13) is not disposed; and a drive mechanism (Ds) for driving the movable block (16) by means of fluid. When resin molding the molded object, the control unit (6) performs control to change the driving force of the drive mechanism (Ds).

Description

Technical Field

[0001] This disclosure relates to a resin molding apparatus and a method for manufacturing resin molded articles. Background Technology

[0002] Substrates containing chips are typically used as electronic components by resin sealing. Conventionally, as a resin molding apparatus for sealing substrates, a transfer molding apparatus for manufacturing semiconductor packages by resin sealing substrates such as BGAs (ball grid arrays) is known (for example, see Patent Document 1).

[0003] The method for manufacturing a resin-molded article using the resin molding apparatus described in Patent Document 1 is as follows: An upper mold cavity insert is moved by applying force from a compression helical spring until the end face of the upper mold cavity insert, which covers approximately the entire area of ​​the internal flow path of a cavity without a substrate, is flush with the chip connection surface of the substrate. Molten resin is then supplied to the cavity. At this time, since the force from the molten resin acting on the end face of the upper mold cavity insert exceeds the force applied to the upper mold cavity insert by the compression helical spring, the upper mold cavity insert gradually rises. Next, with the upper mold cavity insert fixed, the lower mold is raised, reducing the cavity volume and completing the filling of the cavity with molten resin.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2019-181872 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] However, the resin molding apparatus described in Patent Document 1 is inefficient because it moves the upper mold cavity insert to a predetermined position by applying force to a pre-set compression helical spring. This is because different helical springs with different application forces are sometimes required depending on the type of product. Furthermore, if the applied force of the compression helical spring is large, it will put a load on the molding resin when the mold is opened, which may cause defects in the resin molded product.

[0009] Therefore, there is a need for a resin molding apparatus and a method for manufacturing resin molded articles that can improve molding accuracy with a simple structure.

[0010] Solution for solving the problem

[0011] The resin molding apparatus disclosed herein is characterized by the following features: comprising: a molding die for holding a molding object on a substrate with a chip disposed thereon, having a cavity for which resin material is supplied; a mold closing mechanism for closing the molding die; and a control unit for controlling the operation of the molding die and the mold closing mechanism, wherein the molding die includes: a movable block for restricting at least a portion of the internal flow path of the cavity where the chip is not disposed; and a drive mechanism for driving the movable block by means of a fluid, wherein when resin molding is performed on the molding object, the control unit performs control to change the driving force of the drive mechanism.

[0012] The method for manufacturing resin molded articles disclosed herein is characterized by the following: a molding step comprising a molding process in which a molded object having a chip disposed on a substrate is resin molded by filling a cavity with resin material supplied from a gate, wherein a movable block is moved by a drive mechanism driven by a fluid, at least a portion of the internal flow path of the cavity without the chip disposed is confined, and the resin molding of the molded object is performed while the driving force generated by the drive mechanism is changed.

[0013] Invention Effects

[0014] According to this disclosure, a resin molding apparatus with a simple structure that improves molding accuracy and a method for manufacturing resin molded articles can be provided. Attached Figure Description

[0015] Figure 1 This is a schematic diagram showing a resin molding apparatus.

[0016] Figure 2 This is a schematic diagram of the molded module.

[0017] Figure 3 This is a rough top view of the molding die.

[0018] Figure 4 yes Figure 3 A rough cross-sectional view along line IV-IV.

[0019] Figure 5 This is a control flowchart for resin molding.

[0020] Figure 6 It is a diagram illustrating the movement of the movable block during resin molding.

[0021] Figure 7 This is a schematic top view of the molding die of another embodiment 1.

[0022] Figure 8 This is a schematic top view of the molding die in another embodiment 2. Detailed Implementation

[0023] Hereinafter, embodiments of the resin molding apparatus and the method for manufacturing resin molded articles of this disclosure will be described based on the accompanying drawings. However, the embodiments are not limited to the following, and various modifications can be made without departing from their spirit.

[0024] [Device Structure]

[0025] A substrate or other molded object containing a semiconductor chip (hereinafter, sometimes simply referred to as a "chip") is sealed with resin and used as an electronic component. This electronic component is used, for example, as a high-frequency module substrate for portable communication terminals, a power control module substrate, or an equipment control substrate. One technique for resin sealing of molded objects is a transfer method for manufacturing semiconductor packages by resin sealing of BGA (ballgrid array) substrates. This transfer method involves: placing a substrate containing a chip in the cavity of a molding die; supplying a resin sheet formed by solidifying powdered resin to the mold's pot and heating and melting it; then, with the mold closed, supplying molten resin from the melted resin sheet to the cavity and allowing it to solidify; and finally, opening the mold to manufacture a resin-molded product.

[0026] In conventional transfer methods, voids (air bubbles) in the resin molded product can lead to molding defects. Therefore, air vents are required in the molding die, and their positions are designed optimally based on the shape of the substrate and chip to prevent voids. However, even with optimal air vents, the flow rate of molten resin in areas of the substrate where chips, resistors, capacitors, etc., are absent is relatively higher than in areas where chips, etc., are present. Due to this speed difference, molten resin flows from the side areas into the chip-containing areas, surrounding air (including gases generated from the molten resin), thus easily creating voids. In particular, when performing molded underfill on a flip-chip substrate with chips on the substrate separated by protruding electrode grounds, the flow rate of molten resin decreases in the narrow area between the substrate and the chip. Molten resin flows from areas without chips into this narrow area, easily creating voids. As a result, molding defects in the resin molded product can occur.

[0027] Therefore, in this embodiment, a resin molding apparatus D with a simple structure to improve molding accuracy and a method for manufacturing resin molded articles are provided. Hereinafter, a flip chip substrate that is rectangular when viewed from above will be used as an example of the object to be molded, and sometimes the direction of gravity is set to downward and the direction opposite to the direction of gravity is set to upward.

[0028] exist Figure 1A schematic diagram of a resin molding apparatus D is shown. In this embodiment, the resin molding apparatus D includes a molding module 3, a supply module 4, a control unit 6, and a conveying mechanism. The molding module 3 includes a molding die C for sealing the object to be molded with powdered or liquid resin. The control unit 6, as software controlling the operation of the resin molding apparatus D, includes a program stored in hardware such as an HDD (Hard Disk Drive) or memory, and is executed by a processor, including an ASIC (Application Specific Integrated Circuit), FPGA (Field Programmable Gate Array), CPU (Central Processing Unit), or other hardware. That is, the control unit 6 is equipped with a processor capable of executing… Figure 5 The processor for the flowchart (program) shown.

[0029] It should be noted that powdered resin includes not only powdered resin but also resin sheets formed from solid resin obtained by compressing powdered resin; both are molten resins that melt and become liquid upon heating. This powdered resin can be either a thermoplastic resin or a thermosetting resin. In the case of thermosetting resins, the viscosity decreases upon heating, and upon further heating, it polymerizes and solidifies, becoming a cured resin. In this embodiment, the powdered resin is preferably a resin sheet formed from solid resin for ease of handling; furthermore, to reliably fill the space between the chip and the substrate, a highly fluid thermosetting resin including micronized fillers is preferred.

[0030] Molding module 3 seals the pre-sealed substrate Sa (an example of the molded object) with resin to form a resin-sealed finished substrate Sb (an example of a resin molded article). Multiple molding modules 3 are provided (three in this embodiment), and each molding module 3 can be independently attached or detached. Details of molding module 3 will be described later.

[0031] The supply module 4 includes a substrate supply mechanism 43, a substrate alignment mechanism 44, a resin supply mechanism 45, and a substrate receiving section 46, serving as a standby position for the loader 41 and unloader 42 included in the conveying mechanism. The substrate supply mechanism 43 delivers the stored pre-sealed resin substrate Sa to the substrate alignment mechanism 44. One or more semiconductor chips are mounted on the pre-sealed resin substrate Sa in a longitudinal and / or transverse arrangement. The substrate alignment mechanism 44 prepares the pre-sealed resin substrate Sa delivered from the substrate supply mechanism 43 for conveying. The resin supply mechanism 45 stores resin sheets T and configures the resin sheets T for conveying.

[0032] The conveying mechanism includes a loader 41 and an unloader 42. The loader 41 conveys a resin-sealed pre-seal substrate Sa with a semiconductor chip mounted on it before resin sealing, and a resin sheet T. The unloader 42 conveys a resin-sealed completed substrate Sb after resin sealing. The loader 41 can receive multiple (four in this embodiment) resin-sealed pre-seal substrates Sa from the substrate arrangement mechanism 44, and multiple (six in this embodiment) resin sheets T from the resin supply mechanism 45. It moves along a track from the supply module 4 to each molding module 3, transferring the resin-sealed pre-seal substrates Sa and resin sheets T to each molding module 3. The unloader 42 can remove the resin-sealed completed substrate Sb from the molding module 3, move along a track from each molding module 3 to the substrate receiving portion 46, and receive the resin-sealed completed substrate Sb in the substrate receiving portion 46. In the resin-sealed completed substrate Sb, the semiconductor chip is sealed with cured resin formed by the curing of molten resin.

[0033] The following is a detailed description of molding module 3.

[0034] like Figure 2 As shown, the molding module 3 has tie bars 32 erected at the four corners of a rectangular lower fixing plate 31 when viewed from above. An upper fixing plate 33, also rectangular when viewed from above, is located near the upper end of the tie bars 32. A movable platform 34, also rectangular when viewed from above, is located between the lower fixing plate 31 and the upper fixing plate 33. The movable platform 34 has holes at its four corners for the tie bars 32 to pass through, allowing it to move up and down along the tie bars 32. A mold-closing mechanism 35, serving as a device for moving the movable platform 34 up and down, is located above the lower fixing plate 31. This mold-closing mechanism 35 includes an electric motor Ma and a load sensor Wa. The electric motor Ma, as a drive source, is composed of a servo motor or the like. The load sensor Wa is composed of a strain gauge, a force sensor, or the like, used to measure the clamping force (hereinafter referred to as "clamping force") of the molding die C. The mold closing mechanism 35 can close the molding die C by moving the movable platen 34 upward, and open the molding die C by moving the movable platen 34 downward.

[0035] The forming mold C has a lower mold LM and an upper mold UM. The lower mold LM and the upper mold UM are composed of molds arranged opposite each other.

[0036] A substrate placement section is formed in the lower mold LM, which holds the resin-sealing pre-substrate Sa with the side containing semiconductor chips or the like facing upwards. Furthermore, a lower heater 36 is built into the lower mold LM to heat the resin-sealing pre-substrate Sa and the resin sheet T. A cylindrical material cylinder 21 for filling the resin sheet T (resin molten by heating) is fixed in the lower mold LM by thermoforming or the like. A plunger 25, driven by an electric motor Mb such as a servo motor, is inserted below the cylindrical space of the material cylinder 21 in a vertically movable manner. Additionally, the lower mold LM has a load sensor Wb, which is composed of a strain gauge, a force sensor, or the like for measuring the force (hereinafter referred to as "transmitted force") exerted by the plunger 25 to expel molten resin Ta (an example of resin material).

[0037] The upper mold UM has a rectangular cavity MC (viewed from top view) supplied with molten resin Ta, and an upper heater 37 is built into the cavity MC for heating. The upper mold UM includes a cavity block with the cavity MC and a residual material block. The residual material block has a flow channel 22 for the molten resin Ta to flow from the barrel 21 toward the cavity MC, and an exhaust port 26 for venting air from the cavity MC. The cavity block and the residual material block are fixed to the upper mold UM as separate components. The residual material block has a gate 23 as an inlet for the molten resin Ta to flow from the flow channel 22 into the cavity MC. It should be noted that the cavity block and the residual material block can also be configured as a single component. In addition, the exhaust port 26 can also be configured as an exhaust port block separate from the cavity block.

[0038] use Figures 3-4 The molding die C is described in detail. Figure 3 The image shows a schematic top view of the cavity MC as seen from above. Figure 4 Is with Figure 3 A schematic cross-sectional view along line IV-IV in the vertical direction (up-down direction) of the paper. It should be noted that in this embodiment, the case where the surface of chip 13 is exposed during molding is described (see reference...). Figure 4 However, it could also be a case where the surface of chip 13 is sealed with resin.

[0039] like Figure 3 As shown, gate 23 is located in the center of one side S of cavity MC. Molten resin Ta flowing from the aforementioned barrel 21 to the runner 22 is supplied to cavity MC through gate 23. A vent 26 is provided on the other side E of cavity MC opposite to side S, through which air can be discharged from cavity MC. Figures 3-4As shown, the resin-sealed substrate Sa in this embodiment is composed of a flip-chip substrate: the chip 13 is electrically connected to a plurality of protruding electrodes 12 arranged in a two-dimensional array on the substrate 11. The protruding electrodes 12 and the chip 13 are mounted in the central region of the substrate 11 when viewed from above. The central region of the substrate 11 becomes the chip presence region, and the peripheral region surrounding the central region of the substrate 11 becomes the chip absence region. The chip 13 is composed of an IC chip, etc., on which many electronic components and wiring are mounted.

[0040] In such a flip-chip substrate, molten resin Ta supplied from gate 23 flows from one side S (flow start) of cavity MC towards the other side E (flow end). At this time, in the side region of substrate 11 where no chip 13 is placed (along the two sides connecting one side S of cavity MC to the other side E), the flow velocity of molten resin Ta is relatively high compared to the chip presence region (central region of substrate 11) where chip 13 is present. Due to this velocity difference, molten resin Ta wraps around the chip presence region from the side region and surrounds air (including gas generated from molten resin Ta), thus easily generating voids. In particular, in the case of a flip-chip substrate where chip 13 is present on substrate 11 across protruding electrode 12, since the flow velocity of molten resin Ta is relatively low in the narrow region between substrate 11 and chip 13 (the region where protruding electrode 12 is present) compared to the side region where chip 13 is not present, molten resin Ta tends to wrap around the narrow region from the side region, easily generating voids.

[0041] Therefore, the molding die C (upper die UM) of this embodiment includes a movable block 16, a drive mechanism Ds, and a compression spring Sp. The movable block 16 restricts the side flow path 15 (an example of at least a portion of the internal flow path of the cavity MC) of the molten resin Ta flowing inside the cavity MC on both sides intersecting with one side S and the other side E. The drive mechanism Ds is composed of a cylinder or the like that drives the movable block 16 using air (an example of a fluid). The compression spring Sp applies an upward force to the movable block 16. In this embodiment, the movable block 16 is provided on the upper die UM in a way that allows it to move freely up and down, and is located in the region of the pair of side flow paths 15 of the cavity MC opposite to the chip 13. The movable block 16 restricts the side flow path 15 (reduces the flow path cross-sectional area of ​​the side flow path 15) for a predetermined time from the start of the supply of molten resin Ta, thereby reducing the flow rate of molten resin Ta flowing in the side flow path 15. In this embodiment, the movable block 16 is a cuboid, and its width W2 is approximately 90% of the width W1 of the side flow path 15 (i.e., the minimum width from the side of the chip 13 to the wall of the cavity MC). The ratio of the width W2 of the movable block 16 to the width W1 of the side flow path 15 can be appropriately set considering factors such as the viscosity of the molten resin Ta, the size of the gap between the chip 13 and the substrate 11, and the size and number of the protruding electrodes 12, but is preferably about 50% or more. In a side view, the height of the top end 16a (lower end face) of each movable block 16 located in the narrow region between the substrate 11 and the chip 13 (the gap region between the substrate 11 and the chip 13) restricts the side flow path 15. In other words, when the movable block 16 restricts the side flow path 15, its top end 16a overlaps with the narrow region between the substrate 11 and the chip 13 in a side view.

[0042] The movable block 16 can be inserted into the cavity MC by the driving force of the drive mechanism Ds (hereinafter referred to as "cylinder driving force"). By setting the driving force of the drive mechanism Ds to zero and utilizing the applied force of the compression spring Sp, the inner surface of the upper mold UM adjacent to the cavity MC and the top end 16a (lower end face) of the movable block 16 are made to be in the same plane, thus pulling it out of the cavity MC. Furthermore, when the sum of the applied force of the compression spring Sp and the force exerted on the movable block 16 by the molten resin Ta flowing in the cavity MC exceeds the driving force of the drive mechanism Ds, the movable block 16 moves in such a way that the inner surface of the upper mold UM adjacent to the cavity MC and the top end 16a of the movable block 16 are in the same plane. That is, the movable block 16 can change between a state in which the side flow path 15 of the cavity MC is constricted and a state in which the side flow path 15 is fully open.

[0043] Thus, by using movable blocks 16 that constrict the side flow path 15 of the molten resin Ta flowing inside the cavity MC at the two sides intersecting one side S and the other side E, the flow rate of the molten resin Ta in the side flow path 15 is reduced. As a result, even when the substrate Sa is equipped with a chip 13 and a protruding electrode 12 that act as a flow resistance to the molten resin Ta before resin sealing, the flow velocity of the molten resin Ta on the outside of the cavity MC without the chip 13 is close to the flow velocity of the molten resin Ta on the inside of the cavity MC with the chip 13. As a result, at the flow end (the other side E) of the molten resin Ta flowing inside the cavity MC, the front end of the molten resin Ta on the outside of the cavity MC is close to the front end of the molten resin Ta on the inside of the cavity MC, preventing the molten resin Ta from winding around into the inside and surrounding air. Therefore, voids are less likely to be generated in the resin-sealed substrate Sb (resin molded article), and molding accuracy can be improved.

[0044] [Manufacturing methods for resin molded articles and control methods for resin molding]

[0045] use Figures 1-6 A method for manufacturing a resin-molded article is described. The method for manufacturing a resin-molded article (resin-sealed finished substrate Sb) includes: a supply step, supplying a resin-sealed pre-substrate Sa and a resin sheet T to a molding die C; a mold closing step, closing the molding die C; and a molding step, resin molding the resin-sealed pre-substrate Sa by filling the cavity MC with molten resin Ta supplied from the gate 23. This molding step is the process by which the molding module 3 resin-moldes the resin-sealed pre-substrate Sa from the time the resin-sealed pre-substrate Sa is moved into the molding module 3 until the resin-sealed finished substrate Sb is moved out of the molding module 3, and this molding step includes the mold closing step. In the molding step, the control unit 6 controls the operation of the molding die C and the mold closing mechanism 35. Hereinafter, the following will primarily use... Figures 5-6 The control method of control unit 6 will be explained.

[0046] like Figure 1 As shown, the loader 41 is preheated while the space containing the resin sheet T is insulated. Furthermore, the heaters 36 and 37 are preheated to heat the molding die C (see also...). Figure 2 Then, multiple resin-sealed pre-substrate Sas taken from the substrate supply mechanism 43 are placed on the loader 41. Furthermore, resin sheets T arranged by the resin supply mechanism 45 are accommodated in the accommodating space of the resin sheet T in the loader 41. Then, the loader 41 transports the resin-sealed pre-substrate Sas to the molding module 3, places the resin-sealed pre-substrate Sas with the side containing the semiconductor chip facing upwards in the substrate placement section of the lower mold LM, and accommodates the resin sheets T in the barrel 21 (see reference). Figure 2 ,for Figure 5(#51). The resin sheet T is heated into molten resin Ta by housing the resin sheet T in the barrel 21 and the lower heater 36 built into the lower mold LM. It should be noted that before the movable platform 34 is raised by the mold closing mechanism 35 as described later, it is pre-set to a state in which the release film (not shown) is adsorbed onto the mold surface below the upper mold UM.

[0047] Next, as Figure 2 As shown, the movable platform 34 is moved upward by the mold clamping mechanism 35, causing the lower mold LM to move relative to the upper mold UM, so that the lower mold LM and the upper mold UM are in close contact. Next, the control unit 6 sets the driving force of the drive mechanism Ds to Middle (e.g., 1t) to lower the movable block 16, pre-set to a state where the movable block 16 restricts the side flow path 15 (the movable block 16 is almost in contact with the lower mold LM), and air is discharged from the cavity MC through the vent 26 (see reference). Figures 3-4 ,for Figure 5 #52 Figure 6 The "cylinder driving force" at time point T0). Then, the control unit 6 actuates the mold clamping mechanism 35 to increase the clamping force to a specified value ( Figure 5 #53, Figure 6 The "clamping force" at time points T0 to T1. In this embodiment, since the clamping force occurs before the mold C begins to close ( Figure 6 At time points T0 to T1, the driving force of the drive mechanism Ds is set to a relatively small force, thus preventing deformation of the molding die C caused by the movable block 16. Furthermore, the predetermined value to which the clamping force rises can be preset as the clamping force for mold closing, and the clamping force can be measured by the load sensor Wa. It should be noted that the clamping force in this embodiment is as described later. Figure 6 T7 remains at the specified value until then, however, it is also possible that... Figure 6 After the time point T1 rises to below the specified value, Figure 6 The T1 to T5 values ​​rise to the specified values.

[0048] Next, the control unit 6 raises the driving force of the drive mechanism Ds to a high level (e.g., 1.5t) and maintains it. Figure 5 #54, Figure 6 (The "cylinder driving force" at time point T1). Furthermore, the electric motor Mb moves the plunger 25 upwards, causing the molten resin Ta to flow from the barrel 21 through the runner 22 to the gate 23 (see reference). Figure 2 ,for Figure 5 #55 Figure 6 (The "transfer position" at time points T1 to T2). As a result, molten resin Ta is supplied to the cavity MC.

[0049] like Figure 3As shown, molten resin Ta supplied from gate 23 flows from one side S of cavity MC towards the other side E. Then, the molten resin Ta reaching the chip presence area enters a narrow region between substrate 11 and chip 13 in the central region of substrate 11, reducing the flow rate. The protruding electrode 12 between chip 13 and substrate 11 also obstructs the flow of molten resin Ta, further reducing the flow rate. At this time, in the side region of substrate 11, the movable block 16 confines the side flow path 15 for a predetermined time, thereby reducing the flow rate of molten resin Ta. As a result, in the narrow region between substrate 11 and chip 13 and in the side flow path 15, the flow velocity of molten resin Ta is similar, and at the flow end of molten resin Ta flowing inside cavity MC, the leading edge of molten resin Ta is approximately parallel to the other side E of cavity MC. This prevents molten resin Ta from wrapping around to the inside from the outside at the flow end (the other side E) and surrounding air.

[0050] Next, as the molten resin Ta fills the cavity MC, the force exerted by the plunger 25 to expel the molten resin Ta increases as the plunger 25 moves upward. Figure 6 (The "transmitted force" at time points T2 to T4). Then, when the combined force of the applied force of the compression spring Sp and the force exerted on the movable block 16 by the molten resin Ta flowing in the cavity MC exceeds the driving force of the drive mechanism Ds, the movable block 16 naturally rises until the top end 16a of the movable block 16 and the inner surface of the upper mold UM adjacent to the cavity MC are on the same plane. Figure 5 #56, Figure 6 (Time point T3, "movable block position"). In this embodiment, with the driving force of the drive mechanism Ds fixed, the movable block 16 is raised by the force of the molten resin Ta flowing in the cavity MC. Therefore, the air trapped in the narrow area between the substrate 11 and the chip 13 flows towards the side flow path 15 and is discharged to the outside from the narrow area between the substrate 11 and the chip 13. As a result, the air between the substrate 11 and the chip 13 can be removed, and it is less likely to produce voids in the substrate Sb after the resin sealing is completed, thereby improving molding accuracy.

[0051] When the transmission force reaches the set value, the control unit 6 maintains the transmission force to perform the curing process for the specified time. Figure 6 The "transfer force" (time points T4 to T7). This setting value can be preset as the transfer force at the start of curing, and the transfer force can be measured by the load sensor Wb. After the first set time has elapsed since the start of curing, the control unit 6 reduces the driving force of the drive mechanism Ds from high to low (e.g., 0t). Figure 5 #57, Figure 6The "cylinder driving force" T5 time point). This first set time can be preset as the elapsed time from when the transmitted force reaches the set value (a few seconds after the start of curing). By reducing the driving force of the drive mechanism Ds to a low level (e.g., 0t), the movable block 16 can be reliably raised by the applied force of the compression spring Sp even if it does not rise due to the force of the molten resin Ta flowing in the cavity MC.

[0052] When the second set time has elapsed since the start of curing, the control unit 6 increases the driving force of the drive mechanism Ds from low to medium (e.g., 1t). Figure 5 #58, Figure 6 The "cylinder driving force" T6 time point). This second set time is longer than the first set time and is preset to the time before the end of curing (several seconds before). Therefore, it is the time obtained by subtracting the set time from the prescribed curing time. It should be noted that in this embodiment, the driving force of the drive mechanism Ds before the end of curing is set to medium, but it is only necessary to set a driving force that will not cause damage to the substrate Sb after the resin is sealed.

[0053] After curing is complete, the control unit 6 reduces the clamping force of the mold closing mechanism 35, thereby moving the movable platform 34 downward to open the molding die C (see reference). Figure 2 ,for Figure 6 The "clamping force" at time point T7. Then, the resin-sealed substrate Sb is demolded from the cavity MC, ending the resin molding process. Figure 5 #59). In this embodiment, since the driving force of the drive mechanism Ds is raised to the middle before the curing is completed, the demolding of the substrate Sb can be assisted by the descending movable block 16 to complete the resin sealing process. Figure 6 (After the "movable block position" T7). The resin-sealed substrate Sb is accommodated in the substrate receiving part 46 by the unloading machine 42 (see also...). Figure 1 ).

[0054] [Another implementation method]

[0055] Hereinafter, for ease of understanding, the same terms and reference numerals will be used to describe the same components as in the embodiments described above.

[0056] <1> For example Figure 7As shown, in this embodiment, the molded object has a chip 13 mounted in the central region of the substrate 11, and multiple independent passive components 14, such as capacitors, coils, and resistors, mounted in the side region of the substrate 11. In this case, multiple movable blocks 16A that restrict the side flow path 15 are positioned to avoid the independent passive components 14. The size and arrangement of these movable blocks 16A are determined by considering the flow rate of the molten resin in the narrow region between the substrate 11 and the chip 13, the flow resistance of the independent passive components 14, and their mounting area. In other words, the size and arrangement of the movable blocks 16A are determined through simulation to make the flow rate of the molten resin in the narrow region between the substrate 11 and the chip 13 and the side flow path 15 approximately equal.

[0057] <2> For example Figure 8 As shown, in this embodiment, a chip 13 is mounted in the central region of the substrate 11, and multiple independent passive components 14, such as capacitors, coils, and resistors, are densely mounted on both sides of the chip 13. In this case, since it is not possible to arrange movable blocks 16B in the side region of the chip 13, a pair of movable blocks 16B that restrict the side flow path 15 are arranged in the side region of the substrate 11 closer to the gate 23 than the chip 13. As a result, the flow path of molten resin Ta in the side region of the substrate 11 from the gate 23 to the chip 13 is restricted, making the flow rate of molten resin Ta outside the cavity MC where the chip 13 does not exist close to the flow rate of molten resin Ta in the narrow region between the substrate 11 and the chip 13. In the movable blocks 16B of this embodiment, the size and arrangement are also determined by considering the flow rate of molten resin Ta in the narrow region between the substrate 11 and the chip 13, the flow resistance of the independent passive components 14, and the mounting area.

[0058] <3> The fluid used to drive the movable block 16 via the drive mechanism Ds can also be a liquid. Furthermore, the control method for changing the driving force of the drive mechanism Ds via the control unit 6 is not limited to the embodiments described above. For example, the control to reduce the driving force of the drive mechanism Ds after curing begins or the control to increase the driving force of the drive mechanism Ds before curing ends can be omitted.

[0059] <4> In the above embodiments, the movable blocks 16, 16A, and 16B are only configured in the side flow path 15, but they can also be configured adjacent to the gate 23 or the vent 26 in the internal flow path of the cavity MC.

[0060] <5> Molding module 3 may also have a release film supply mechanism (not shown). This release film supply mechanism supplies release film to the upper mold UM, so that the supplied release film adheres to the mold surface of the upper mold UM. By adhering the release film to the mold surface of the upper mold UM, demolding is facilitated, and the molten resin Ta is prevented from flowing into the gap in the upper mold UM for the movable block 16 to move.

[0061] <6> Alternatively, a protrusion or recess may be applied to the top 16a of the movable block 16. In this case, when the movable block 16 is brought into close contact with the substrate 11, the protrusion or recess can restrict the side flow path 15. The top 16a and the protrusion or recess will abut against the substrate 11, so there is no need to precisely control the gap between the movable block 16 and the substrate 11.

[0062] <7> In the above embodiment, an example of the protruding electrode 12 being configured in a grid pattern is shown, but it can be configured in a two-dimensional array pattern, for example, it can also be configured in the form of two arrays.

[0063] <8> The barrel 21, cavity block, and residual material block can be located in either the upper mold UM or the lower mold LM. Alternatively, the gate 23 can be provided covering the entire area of ​​one side S of the cavity MC; the arrangement and number of gates 23 are not particularly limited. Furthermore, the molding object, such as the resin-sealed substrate Sa, can be fixed to the upper mold UM, and the cavity MC can be located in the lower mold LM.

[0064] <9> The molded object sealed by resin is not limited to a flip chip substrate; any type of molded object can be used, even if it is a substrate on which semiconductor chips are mounted. Furthermore, the resin molding apparatus D described above can also be used to manufacture MAP (molded array packaging) in which multiple substrates on which semiconductor chips are mounted are sealed together with resin.

[0065] <10> In the above embodiment, the method of exposing the surface of the chip 13 during molding has been described, but it is also possible to seal the surface of the chip 13 with resin. In this case, a movable block 16 may be provided above the chip 13 to temporarily prevent the flow of molten resin Ta from the gate 23 toward the vent 26 across the upper surface of the chip 13.

[0066] [Summary of the above embodiments]

[0067] Hereinafter, a summary of the resin molding apparatus D and the method for manufacturing the resin molded article described in the above embodiments will be given.

[0068] (1) The resin molding apparatus D has the following features: a molding die C, which holds a resin sealing substrate Sa (the object to be molded) on a substrate 11 on which a chip 13 is disposed, and has a cavity MC in which molten resin Ta (resin material) is supplied from a gate 23; a mold closing mechanism 35 for closing the molding die C; and a control unit 6 for controlling the operation of the molding die C and the mold closing mechanism 35. The molding die C includes: a movable block 16 for limiting at least a portion (side flow path 15) of the internal flow path of the cavity MC where the chip 13 is not disposed; and a drive mechanism Ds for driving the movable block 16 with air (fluid). When resin molding is performed on the resin sealing substrate Sa (the object to be molded), the control unit 6 performs control to change the driving force of the drive mechanism Ds.

[0069] In this structure, a movable block 16 is provided to restrict at least a portion of the internal flow path of the cavity MC where the chip 13 is not located. As a result, the flow velocity of the molten resin Ta in the region of the cavity MC where the chip 13 is not located can be made close to the flow velocity of the molten resin Ta in the region of the cavity MC where the chip 13 is located. This prevents the molten resin Ta from wrapping around the chip 13 side from the region of the cavity MC where the chip 13 is not located and surrounding the air. Moreover, in this structure, when resin molding is performed on the substrate Sa (the object to be molded) before resin sealing, the driving force of the air-driven drive mechanism Ds is changed. Therefore, for example, compared to the case where the applied force of the movable block 16 is fixed, since the driving force of the drive mechanism Ds is changed according to the situation, molding accuracy can be improved with a simple structure.

[0070] (2) Alternatively, when the clamping force of the mold clamping mechanism 35 reaches a specified value, the control unit 6 increases the driving force of the drive mechanism Ds.

[0071] If, as in this structure, the driving force of the drive mechanism Ds increases when the clamping force of the mold closing mechanism 35 reaches a specified value, it can prevent defects such as the movable block 16 strongly contacting the molding die C before mold closing, causing the molding die C to deform.

[0072] (3) Alternatively, the control unit 6 may reduce the driving force of the drive mechanism Ds after the curing begins.

[0073] If, as in this structure, the driving force of the drive mechanism Ds is reduced after curing begins, the movable block 16 can be reliably moved outside the cavity MC.

[0074] (4) Alternatively, the control unit may increase the driving force of the drive mechanism Ds before the curing is completed.

[0075] In this structure, since the driving force of the drive mechanism Ds is increased before the curing is completed, the movable block 16 can assist the resin seal in completing the demolding of the substrate Sb.

[0076] (5) The method for manufacturing a resin molded article is characterized by the following: a molding process is included in which a resin-sealed pre-substrate Sa (the object to be molded) on a substrate 11 is resin-molded by filling a cavity MC with molten resin Ta (resin material) supplied from a gate 23. In the molding process, a movable block 16 is moved by a drive mechanism Ds driven by air (fluid) to restrict at least a portion (side flow path 15) of the internal flow path of the cavity MC without the chip 13, and the resin molding of the resin-sealed pre-substrate Sa (the object to be molded) is performed while the driving force generated by the drive mechanism Ds changes.

[0077] In this method, the flow rate of molten resin Ta in the region of the cavity MC where the chip 13 is not present can be made close to the flow rate of molten resin Ta in the region of the cavity MC where the chip 13 is present during the molding process. This prevents molten resin Ta from flowing around into the chip 13 side of the cavity MC from the region where the chip 13 is not present and surrounding the air. Furthermore, in this method, when resin molding is performed on the substrate Sa before resin sealing, the driving force of the air-driven drive mechanism Ds is changed. Therefore, for example, compared to the case where the applied force of the movable block 16 is fixed, since the driving force of the drive mechanism Ds is changed according to the situation, molding accuracy can be improved.

[0078] It should be noted that, without creating contradictions, the structures disclosed in the above-described embodiments (including another embodiment, the same below) can be applied in combination with the structures disclosed in other embodiments. Furthermore, the embodiments disclosed in this specification are examples, and the embodiments disclosed herein are not limited thereto, and can be appropriately modified without departing from the purpose of this disclosure.

[0079] Industrial availability

[0080] This disclosure can be applied to resin molding apparatus and methods for manufacturing resin molded articles. In particular, it is effective in thick-layer encapsulation where the thickness of the sealing resin is 1 mm or more, in automotive encapsulation, and in underfill molding of flip-chip substrates with a gap of 100 μm or less between the substrate and the chip.

[0081] Explanation of reference numerals in the attached figures

[0082] 11: Substrate; 13: Chip; 15: Side flow path (at least a portion of the internal flow path of the cavity); 16: Movable block; 23: Gate; 35: Mold closing mechanism; C: Molding mold; D: Resin molding device; MC: Cavity; Sa: Substrate before resin sealing (molded object); Sb: Substrate after resin sealing (resin molded article); Ta: Molten resin (resin material).

Claims

1. A resin molding apparatus, comprising: A molding die holds a molded object on a substrate with a chip disposed thereon, and has a cavity from which resin material is supplied from a gate; A mold closing mechanism for closing the molding mold; as well as The control unit controls the movement of the molding die and the mold closing mechanism. The molding die includes: A movable block that restricts at least a portion of the internal flow path of the cavity where the chip is not configured; And a drive mechanism that uses fluid to drive the movable block. When the object to be molded is resin molded, the control unit performs control to change the driving force of the drive mechanism. When the clamping force of the mold clamping mechanism reaches a predetermined value, the control unit increases the driving force of the drive mechanism.

2. The resin molding apparatus according to claim 1, wherein, The control unit reduces the driving force of the drive mechanism after curing begins.

3. The resin molding apparatus according to claim 1 or 2, wherein, The control unit increases the driving force of the drive mechanism before the curing process ends.

4. A method for manufacturing a resin molded article, comprising a molding step of resin molding an object having a chip disposed on a substrate by filling a mold cavity with resin material supplied from a gate. In the molding process, a movable block is moved by a fluid-driven drive mechanism, which restricts at least a portion of the internal flow path of the cavity where the chip is not located, causing a change in the driving force generated by the drive mechanism. When the clamping force of the mold closing mechanism reaches a predetermined value, the driving force of the drive mechanism is increased to perform resin molding of the molded object.

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