JP7521272B2 - Resin sealing method and resin sealing mold - Google Patents

Description

The disclosed embodiments relate to a resin sealing method and a resin sealing mold.

In the resin sealing method used to manufacture various semiconductor packages, etc., a large amount of resin is used for resin sealing due to demands such as an increase in the number of semiconductor packages that can be removed from one resin sealing or larger semiconductor packages.

As an example of a resin sealing device that attempts to prevent resin from being left unfilled by sufficiently melting the resin, there is a resin sealing device described in Patent Document 1.

The resin sealing device described in Patent Document 1 has a required number of pots in either a fixed or movable mold, and a cull section consisting of a recess that forms a cull, which is a resin supply path, arranged opposite the pots in the other mold, and dedicated heating means are provided for the pots and the cull section.

Japanese Utility Model Application Publication No. 2-31130

Here, the resin sealing device described in Patent Document 1 does not adequately guarantee temperature control when a large amount of resin is used in one resin sealing, and there is a concern that when a large amount of resin is poured into the pot and injected into the cavity through the cull section, the heat around the cull block will be taken away by the resin, causing a drop in the mold temperature.

For example, if the resin is not given enough heat to harden, the effect of preventing resin underfilling by sufficiently melting the resin and sufficiently hardening the resin after injection into the cavity cannot be achieved, which may lead to molding defects.

In addition, some conventional resin sealing devices use heaters and sensors placed inside the die set to control the temperature of the mold, but because the sensor in the die set is generally far from the cull block or cavity block, it is difficult to detect a drop in temperature in each block.

Even if the sensor could detect a drop in temperature in the cull block or cavity block, there would be a time lag between the occurrence of the drop in temperature and its detection. As a result, it was not possible to control the temperature around each block in real time.

Furthermore, even if a drop in temperature in the cull block or cavity block is detected and the mold is heated, it takes a considerable amount of time for the mold temperature to rise again when heating is started after detection. This makes it difficult to fully resolve the problem of the resin not melting sufficiently or not hardening after being injected into the cavity.

One aspect of the embodiment has been made in consideration of the above, and aims to provide a resin sealing method and a resin sealing mold that can control the temperature of the mold with high precision when resin sealing is performed with the mold.

The resin sealing method according to one aspect of the embodiment is a resin sealing method that performs multiple molding operations by repeating an operation of resin sealing a semiconductor element placed on a substrate as one molding operation using a resin sealing mold having a mold body provided with a cull block having a cull portion composed of a recess that forms a cull, which is a resin supply path, and a cavity block that forms a cavity, a temperature measuring means that measures the temperature of at least one of the cull block and the cavity block, and a heating means that heats at least one of the cull block and the cavity block, and includes an acquisition step of acquiring information on temperature changes of at least one of the cull block and the cavity block in each molding operation of the multiple molding operations by the temperature measuring means, a calculation step of calculating the adjustment content of heating in one molding operation by the heating means until a molding operation subsequent to the previous one is performed based on the information on temperature changes acquired in the acquisition step in a molding operation prior to the previous one among the multiple molding operations, and an execution step of performing heating by the heating means in a molding operation subsequent to the previous one based on the adjustment content calculated in the calculation step.

Here, the temperature measuring means measures the temperature of at least one of the cull block and the cavity block, thereby making it possible to obtain information on the temperature change in the cull block and information on the temperature change in the cavity block when the semiconductor element is resin-encapsulated. Note that the temperature of the cull block or the cavity block here refers to the temperature when the cull block or the cavity block is measured around (near) the temperature measuring means.

In addition, the calculation step calculates the adjustment content of heating in one molding operation by the heating means until the molding operation after the previous one is performed based on the information of the temperature change measured by the temperature measurement means in the molding operation before the previous one, and performs heating by the heating means in the molding operation after the previous one according to the calculated adjustment content, so that the temperature of at least one of the cull block and the cavity block can be adjusted to the desired temperature based on the temperature change in at least one of the cull block and the cavity block. This allows the temperature control of the mold body with high accuracy during resin sealing. Note that heating at least one of the cull block and the cavity block by the heating means includes heating at least one of the cull block and the cavity block with the heating means, and the heat is transmitted inside the mold body, thereby increasing the temperature near the surface of each block. In addition, the molding operation before the previous one includes the previous molding operation, and does not only refer to the previous molding operation, but may also include molding operations two or more times before. Also, when the previous molding operation is used as the reference, the molding operation one operation before that or the molding operation two operations before that may be applicable.

In addition, the execution process can perform heating by the heating means in a molding operation subsequent to the previous one based on the adjustment content calculated in the calculation process, without using information on the temperature measured by the temperature measurement means in a molding operation subsequent to the previous one.

The calculation process also calculates at least one of the heating output, time, and timing of the heating by the heating means as the adjustment contents.

The calculation process uses a calculation model generated by machine learning that takes as input temperature change information, which is information on the temperature change acquired in the acquisition process in the previous or previous molding operation, and outputs adjustment content information, which is information on the adjustment content of the heating by the heating means. This allows the temperature of the mold body to be controlled with high precision during resin sealing.

In addition, this resin sealing method further includes a learning process for generating a calculation model based on the temperature change information and the adjustment content information. This allows the calculation model to be generated and updated while the molding operation is being performed.

In addition, the cull block and cavity block are provided with multiple temperature control areas where temperature measurement by the temperature measurement means and heating by the heating means can be performed individually, and the calculation process calculates the heating output, time, and timing by the heating means for each temperature control area in a molding operation after the previous one. This allows the cull block and cavity block to be divided into multiple temperature control areas, and the temperature can be adjusted by the heating means for each temperature control area.

The multiple temperature adjustment regions include at least a first temperature adjustment region and a second temperature adjustment region different from the first temperature adjustment region, and the calculation step calculates the heating output, time, and timing by the heating means corresponding to the second temperature adjustment region in the molding operation after the previous one based on information on the relative temperatures between the first temperature adjustment region and the second temperature adjustment region in the molding operation before the previous one and information on the temperature change in the first temperature adjustment region. In this case, the heating output, time, and timing by the heating means can be calculated so that the first temperature adjustment region and the second temperature adjustment region are at the desired temperatures in the molding operation after the previous one.

The calculation step also calculates the heating output, time, and timing by the heating means in the molding operation after the previous one for each of the multiple temperature adjustment regions based on the temperature change information. This allows the heating output, time, and timing by the heating means to be adjusted so that the temperature of each temperature adjustment region in the molding operation after the previous one for each of the multiple temperature adjustment regions becomes the desired temperature.

The cull block is formed with multiple cull sections, and the temperature measurement means includes a sensor that measures the temperature between the multiple cull sections of the cull block. This makes it possible to measure the temperatures of multiple cull sections at once, for example.

The resin sealing mold according to one embodiment has a mold body provided with a cull block that forms a cull, which is a resin supply path, and a cavity block that forms a cavity, a temperature measuring means that measures the temperature of at least one of the cull block and the cavity block, a heating means that heats at least one of the cull block and the cavity block, and an execution unit that executes heating by the heating means, and is a resin sealing mold that performs multiple molding operations by repeating an operation of resin sealing a semiconductor element placed on a substrate as one molding operation, in which the temperature measuring means acquires information on temperature changes of at least one of the cull block and the cavity block in each of the multiple molding operations, and the execution unit includes a calculation unit that calculates adjustments to heating by the heating means in one molding operation by the heating means based on information on temperature changes acquired by the temperature measuring means in a molding operation prior to the previous one among the multiple molding operations, until a molding operation subsequent to the previous one is performed, and a heating execution unit that executes heating by the heating means in a molding operation subsequent to the previous one based on the adjustments calculated by the calculation unit.

Here, the resin sealing mold has an execution section that performs heating using a heating means, so that the temperature of at least one of the cull block and the cavity block can be adjusted during resin sealing.

In addition, the execution unit executes heating by the heating means based on information on temperature changes measured by the temperature measurement means during the previous molding operation, and thus, based on information on temperature changes in at least one of the cull block and the cavity block, heating by the heating means can be executed so that the temperature of at least one of the cull block and the cavity block becomes the desired temperature.

According to one aspect of the embodiment, it is possible to provide a resin sealing method and a resin sealing die that can control the temperature of the die with high precision when performing resin sealing with the die.

FIG. 1 is a schematic explanatory diagram showing a resin sealing apparatus including a resin sealing die which is an example of a resin sealing die according to an embodiment. Figure 2(a) is a schematic diagram showing the arrangement of the upper cull section sensor and upper cull section heater, as well as the upper cavity sensor and upper cavity heater in the upper die chess, Figure 2(b) is a schematic diagram showing the arrangement of the lower cull section sensor and lower cull section heater, as well as the lower cavity sensor and lower cavity heater in the lower die chess, Figure 2(c) is a schematic front view of the upper die, and Figure 2(d) is a schematic front view of the lower die. FIG. 3(a) is a schematic diagram showing the arrangement of an upper die set sensor and an upper die set heater in an upper die set, and FIG. 3(b) is a schematic diagram showing the arrangement of a lower die set sensor and a lower die set heater in a lower die set. Figure 4(a) is a schematic diagram showing another example of the arrangement of the upper cull section sensor and upper cull section heater, and the upper cavity sensor and upper cavity heater in the upper chess, and Figure 4(b) is a schematic diagram showing another example of the arrangement of the lower cull section sensor and lower cull section heater, and the lower cavity sensor and lower cavity heater in the lower chess. Figure 5(a) is a schematic diagram showing yet another example of the arrangement of an upper cull section sensor and upper cull section heater, and an upper cavity sensor and upper cavity heater in an upper chess, and Figure 5(b) is a schematic diagram showing yet another example of the arrangement of a lower cull section sensor and lower cull section heater, and a lower cavity sensor and lower cavity heater in a lower chess. FIG. 6 is a diagram illustrating an example of a configuration of the control unit according to the first embodiment. Figure 7 is an explanatory diagram of the pre-forming method when predicting and controlling the upper cull block, where Figure 7(a) is a flow chart showing the process of calculating the values of various parameters from normal forming, and Figure 7(b) is a conceptual diagram of the state in which the values of various parameters are reflected in the ON/OFF control of the upper cull section heater. Figure 8(a) is a graph showing a first example of the results of measuring information on temperature change in the upper cull block by a cull section sensor when a molding operation is performed in a resin sealing device in which a cull section sensor and a cull section heater are provided in the cull block, and Figure 8(b) is a diagram showing an example of various parameters calculated based on the temperature change in the upper cull block shown in Figure 8(a). Figure 9(a) is a graph showing a second example of the results of measuring information on temperature change in the upper cull block by a cull section sensor when a molding operation is performed in a resin sealing device in which a cull section sensor and a cull section heater are provided in the cull block, and Figure 9(b) is a diagram showing an example of various parameters calculated based on the temperature change in the upper cull block shown in Figure 9(a). Figure 10(a) is a graph showing a third example of the results of measuring information on temperature change of the upper cull block by a cull section sensor when a molding operation is performed in a resin sealing device in which a cull section sensor and a cull section heater are provided in the cull block, and Figure 10(b) is a diagram showing an example of various parameters calculated based on the temperature change of the upper cull block shown in Figure 10(a). Figure 11(a) is a graph showing a fourth example of the results of measuring information on temperature change in the upper cull block by a cull section sensor when a molding operation is performed in a resin sealing device in which a cull section sensor and a cull section heater are provided in the cull block, and Figure 11(b) is a diagram showing an example of various parameters calculated based on the temperature change in the upper cull block shown in Figure 11(a). Figure 12 is a graph showing the results of measuring information on temperature changes in the cull section using a cull section sensor when a molding operation is performed in a resin sealing device in which a cull section sensor and a cull section heater are provided in the cull block. Figure 12(a) shows the result of a first molding operation performed without predictive control, Figure 12(b) shows the result of a second molding operation performed with predictive control based on information on the first temperature change, and Figure 12(c) shows the result of a third molding operation performed with predictive control based on information on the second temperature change. Figure 13 is an example of a graph connecting the lowest and highest temperatures of the upper cull block measured by the cull section sensor during each molding operation when repeated molding operations are performed in a resin sealing device in which a cull section sensor and a cull section heater are provided in the cull block. FIG. 14(a) is a flow diagram showing the flow of the molding operation in which each temperature control area is predictively controlled by individual heater control, and FIG. 14(b) is a schematic diagram showing the temperature control areas A1 to A9 set in the upper die chest. Figure 15(a) is a flow diagram showing the flow of molding operations in which temperature control area A is predictively controlled by heater control, and other temperature control areas are controlled by changing the output ratio of the cull section heater in temperature control area A, and Figure 15(b) is a schematic diagram showing temperature control areas A and B1 to B8 set in the upper die chest.

Below, the embodiments of the resin sealing method and resin sealing mold disclosed in the present application will be described in detail with reference to the attached drawings. Note that the present invention is not limited to the embodiments shown below.

With reference to Figures 1, 2 and 3, the structure of a resin sealing device including an example of a resin sealing mold according to the present invention will be outlined. The resin sealing device S is equipped with a resin sealing mold M, which is an example of a resin sealing mold according to the present invention (see Figure 1). This resin sealing mold M has a pair of upper and lower molds 1 and 2. The resin sealing device S is a device that clamps the upper and lower molds 1 and 2 together to resin seal a semiconductor element (not shown) placed on a substrate such as a lead frame. The resin sealing device S performs multiple molding operations by repeating the operation of resin sealing the semiconductor element placed on the substrate as one molding operation. In each molding operation, a molded product is produced in which the semiconductor element placed on the substrate is resin sealed.

In the following description, the position of the lower die 2 relative to the upper die 1 will be referred to as "lower" or "lower side" and the position of the upper die 1 relative to the lower die 2 will be referred to as "upper" or "upper side" based on FIG. 1. Furthermore, the left side of the paper in FIG. 1 will be referred to as "left" or "left side" and the right side of the paper in FIG. 1 will be referred to as "right" or "right side". Furthermore, the position of the upper cavity block 121 relative to the upper cull block 120 will be referred to as "outside" or "outside" and the position of the upper cull block 120 relative to the upper cavity block 121 will be referred to as "inside" or "inside". Furthermore, based on FIG. 2(a), the lower side of the paper in FIG. 2 will be referred to as "front" or "front side" and the upper side of the paper in FIG. 2 will be referred to as "rear" or "rear side".

Here, the upper mold 1 is composed of an upper die set 11 and an upper die chess 12 (see Figures 1 and 2(c)). The lower mold 2 is composed of a lower die set 21 and a lower die chess 22 (see Figures 1 and 2(d)).

The upper die set 11 is a frame that supports the upper chess piece 12 via a support pillar (not shown). The support pillar is a support member that is connected to the upper die set 11 and the upper chess piece 12 and supports the upper chess piece 12.

When the mold is closed, the upper die chess 12, together with the lower die chess 22, is a member that forms the cull portion 124 (see FIG. 2(a)), which is a recess that forms a cull that is a resin supply path, and the cavity (reference number omitted), which is the resin molding portion.

The lower die set 21 is a frame that supports the lower die chest 22 via a support pillar (not shown). The support pillar is a support member that is connected to the lower die set 21 and the lower die chest 22 and supports the lower die chest 22.

The upper die chess piece 12 also has an upper cull block 120, an upper cavity block 121, a first upper holder base 122, and a second upper holder base 123 (see Figures 1 and 2(c)).

The upper cull block 120 is a member that, together with the lower cull block 220 (described later), forms the cull portion 124 when the mold is closed. The upper cavity block 121 is a member that, together with the lower cavity block 221 (described later), forms the cavity when the mold is closed.

The first upper holder base 122 and the second upper holder base 123 are members supported by support pillars (not shown). The support pillars are connected to the upper die set 11, the first upper holder base 122, and the second upper holder base 123, and are support members that support the upper die set 12.

In addition, the upper cull block 120 is provided with an upper cull section sensor 130 (see Figures 1 and 2 (c)). In addition, an upper cull section heater 140 is provided between the first upper holder base 122 and the second upper holder base 123, and on the top of the upper cull block 120.

The upper cull section sensor 130 is a temperature measuring means that measures the temperature of the upper cull block 120 and information on temperature changes over time.

The upper cull section heater 140 is a heating means for heating the upper cull block 120. The upper cull section heater 140 can adjust the temperature of the upper cull block 120 by adjusting the output, the heating time, and the timing for starting heating. The timing for starting heating here corresponds to the timing of heating by the heating means in the claims of this application.

Figure 2(a) also shows the arrangement of the upper cull sensor 130 and the upper cull heater 140 in the upper chess plate 12. One upper cull sensor 130 is provided on the front side of the upper chess plate 12, near the center (see Figures 1 and 2(c)).

The upper cull sensor 130 is positioned so that it passes between the cull sections 124 on both sides of the upper cull block 120, as shown in the enlarged view of the area indicated by the symbol P in Figure 2(a).

The upper cull heaters 140 are arranged in three rows in the left-right direction near the center of the upper chess plate 12 (see FIG. 2(a)). The upper cull heaters 140 are also arranged so that their longitudinal direction is parallel to the front-to-rear direction of the upper chess plate 12.

In addition, the upper cavity blocks 121 (hereinafter referred to as the left and right upper cavity blocks 121) arranged on the left and right of the upper cull block 120 are each provided with an upper cavity sensor 131 (see Figures 1 and 2(c)). In addition, between the first upper holder base 122 and the second upper holder base 123, and on the tops of the left and right upper cavity blocks 121, upper cavity heaters 141 are each provided (see Figure 1).

The upper cavity sensor 131 is a temperature measuring means that measures the temperature of the left and right upper cavity blocks 121 and information on temperature changes over time.

The upper cavity heater 141 is a heating means for heating the left and right upper cavity blocks 121. The upper cavity heater 141 can adjust the temperature of the left and right upper cavity blocks 121 by adjusting the output, the heating time, and the timing for starting heating.

Adjusting the output of the upper culvert heater 140 and the upper cavity heater 141 includes switching each heater on and off.

Figure 2(a) also shows the arrangement of the upper cavity sensor 131 and the upper cavity heater 141 in the upper die chess 12. Three upper cavity sensors 131 are arranged in the front-to-rear direction in each of the left and right upper cavity blocks 121.

The upper cavity heaters 141 are arranged side by side, one on each side of the upper cull heater 140 in the left-right direction (see FIG. 2(a)). The upper cavity heaters 141 are also arranged so that their longitudinal direction is parallel to the front-to-rear direction of the upper die chess 12.

Here, it is not necessary to provide the upper cull portion sensor 130 and the upper cavity sensor 131 in the upper die chest 12, and a structure in which only one of the sensors is provided may be adopted. However, compared to a structure in which only one sensor is provided, it is preferable to provide the upper cull portion sensor 130 and the upper cavity sensor 131 in the upper die chest 12, because this allows temperature and temperature change information to be obtained in the upper cull block 120 and the left and right upper cavity blocks 121, makes it possible to grasp temperature changes in a finer range within the upper die 1, and makes it easier to adjust the heating by each heater 140, 141.

Furthermore, it is not necessary to provide only one upper cull section sensor 130, and the number is not particularly limited. Furthermore, the position of the upper cull section sensor 130 can also be changed as appropriate.

In addition, it is not necessary to provide three upper cavity sensors 131, and the number is not particularly limited. In addition, the position of the upper cavity sensor 131 can also be changed as appropriate.

In addition, it is not necessary to provide the upper cull portion heater 140 and the upper cavity heater 141 in the upper die chest 12, and a structure in which only one of the heaters is provided may be adopted. However, compared to a structure in which only one heater is provided, it is possible to heat the upper cull block 120 and the left and right upper cavity blocks 121, making it possible to control the temperature in a finer range within the upper die 1, and making it easier to stabilize the temperature throughout the entire upper die 1, so it is preferable to provide the upper cull portion heater 140 and the upper cavity heater 141 in the upper die chest 12.

In addition, it is not necessary to provide three upper cull heaters 140, and the number is not particularly limited. In addition, the position of the upper cull heaters 140 can also be changed as appropriate.

In addition, it is not necessary to provide two upper cavity heaters 141, and the number is not particularly limited. In addition, the position of the upper cavity heater 141 can also be changed as appropriate.

Here, the lower die chess 22 is a member that, together with the upper die chess 12, forms the cull portion 124 and the cavity (symbol omitted) when the die is clamped.

The lower die chess 22 also has a lower cal block 220, a lower cavity block 221, a first lower holder base 222, and a second lower holder base 223 (see Figures 1 and 2(d)).

The lower cull block 220 is a member that, together with the upper cull block 120, forms the cull portion 124 when the mold is closed. The lower cavity block 221 is a member that, together with the upper cavity block 121, forms the cavity when the mold is closed.

The first lower holder base 222 and the second lower holder base 223 are members supported by support pillars (not shown). The support pillars are connected to the lower die set 21, the first lower holder base 222, and the second lower holder base 223, and are support members that support the lower die set 22.

In addition, the lower cull block 220 is provided with a lower cull section sensor 230 (see Figures 1 and 2(d)). In addition, a lower cull section heater 240 is provided between the first lower holder base 222 and the second lower holder base 223, and below the lower cull block 220.

The lower cull section sensor 230 is a temperature measuring means that measures the temperature of the lower cull block 220 and information on temperature changes over time.

The lower cull section heater 240 is a heating means for heating the lower cull block 220. The lower cull section heater 240 can adjust the temperature of the lower cull block 220 by adjusting the output, the heating time, and the timing for starting heating.

Figure 2(b) also shows the arrangement of the lower cull sensor 230 and the lower cull heater 240 in the lower chess plate 22. The lower cull sensor 230 is provided on the front side of the lower chess plate 22, near the center.

The lower cull heater 240 is disposed near the center of the lower chess plate 22 in the left-right direction (see FIG. 2(b)). The lower cull heater 240 is disposed such that its longitudinal direction is parallel to the front-rear direction of the lower chess plate 22.

In addition, the lower cavity blocks 221 (hereinafter referred to as the left and right lower cavity blocks 221) arranged on the left and right of the lower cal block 220 are each provided with a lower cavity sensor 231 (see Figures 1 and 2(d)). In addition, lower cavity heaters 241 are provided between the first lower holder base 222 and the second lower holder base 223, and below the left and right lower cavity blocks 221, respectively.

The lower cavity sensor 231 is a temperature measuring means that measures the temperature of the left and right lower cavity blocks 221 and information on temperature changes over time.

The lower cavity heater 241 is a heating means for heating the left and right lower cavity blocks 221. The lower cavity heater 241 can adjust the temperature of the left and right lower cavity blocks 221 by adjusting the output, the heating time, and the timing for starting heating.

Adjusting the output of the lower culvert heater 240 and the lower cavity heater 241 involves switching each heater on and off.

Figure 2 (b) also shows the arrangement of the lower cavity sensor 231 and the lower cavity heater 241 in the lower die chess 22. Three lower cavity sensors 231 are arranged in the front-to-rear direction in each of the left and right lower cavity blocks 221.

The lower cavity heaters 241 are arranged side by side, one on each side of the lower cull heater 240 in the left-right direction (see FIG. 2(b)). The lower cavity heaters 241 are also arranged so that their longitudinal direction is parallel to the front-to-rear direction of the lower die chess 22.

Here, it is not necessary to provide the lower cull portion sensor 230 and the lower cavity sensor 231 in the lower die chest 22, and a structure in which only one of the sensors is provided may be adopted. However, compared to a structure in which only one sensor is provided, it is preferable to provide the lower cull portion sensor 230 and the lower cavity sensor 231 in the lower die chest 22, because temperature and temperature change information can be obtained in the lower cull block 220 and the left and right lower cavity blocks 221, temperature changes can be grasped in a finer range within the lower die 2, and it is easier to adjust the heating by each heater 240, 241.

Furthermore, it is not necessary to provide one lower cull section sensor 230, and the number is not particularly limited. Furthermore, the position of the lower cull section sensor 230 can also be changed as appropriate.

Furthermore, it is not necessarily required that three lower cavity sensors 231 are provided in each of the left and right lower cavity blocks 221, and the number is not particularly limited. Furthermore, the position of the lower cavity sensors 231 can also be changed as appropriate.

In addition, it is not necessary to provide the lower cull section heater 240 and the lower cavity heater 241 in the lower die chest 22, and a structure in which only one of the heaters is provided may be adopted. However, compared to a structure in which only one heater is provided, it is possible to heat the lower cull block 220 and the left and right lower cavity blocks 221, making it possible to control the temperature in a finer range within the lower die 2, and making it easier to stabilize the temperature throughout the entire lower die 2, so it is preferable to provide the lower cull section heater 240 and the lower cavity heater 241 in the lower die chest 22.

In addition, it is not necessary to provide one lower cull heater 240, and the number is not particularly limited. In addition, the position of the lower cull heater 240 can also be changed as appropriate.

Furthermore, it is not necessarily necessary to provide two lower cavity heaters 241, and the number is not particularly limited. Furthermore, the position of the lower cavity heater 241 can also be changed as appropriate.

Here, the upper die set 11 is provided with an upper die set heater 111 for heating the upper die chess 12, and an upper die set sensor 110 (see Figures 1 and 3(a)). Also, the lower die set 21 is provided with a lower die set heater 211 for heating the lower die chess 22, and a lower die set sensor 210 (see Figures 1 and 3(b)).

The upper die set sensor 110 is a temperature measuring means for measuring the temperature of the upper die set 11. The lower die set sensor 210 is a temperature measuring means for measuring the temperature of the lower die set 21.

When the resin sealing device S is a resin sealing device that produces large molded products, for example, the upper cull section sensor 130, the upper cavity sensor 131, the upper cull section heater 140, the lower cull section sensor 230, the lower cavity sensor 231, and the lower cull section heater 240 can be arranged as shown in Figures 4(a) and 4(b) or Figures 5(a) and 5(b).

In the upper mold 1 shown in Figures 4(a) and 5(a), three upper cull section heaters 140 are arranged in a row in the left-right direction in the upper cull block 120 of the upper mold chess 12, and each upper cull section heater 140 is arranged with its longitudinal direction parallel to the front-to-rear direction of the upper cull block 120. Of the three upper cull section heaters 140, the upper cull section heater 140 located in the center in the left-right direction is located between the cull sections 124 arranged in two rows in the left-right direction. Being located between the cull sections 124 includes being located between the cull sections 124 when viewed from the top-to-bottom direction.

In the upper mold 1 shown in FIG. 4(a), an upper cull portion sensor 130 is disposed above the cull portion 124 in the upper cull block 120, and an upper cavity sensor 131 is disposed above each cavity in the upper cavity block 121.

In the upper mold 1 shown in FIG. 5(a), one upper cull portion sensor 130 is arranged above the cull portion 124 in the upper cull block 120, and upper cavity sensors 131 are arranged on the front and rear sides above each cavity in the upper cavity block 121.

In the lower mold 2 shown in Figures 4(b) and 5(b), one lower cull section heater 240 is disposed near the center in the left-right direction of the lower cull block 220. The lower cull section heater 240 is disposed such that its longitudinal direction is parallel to the front-rear direction of the lower cull block 220.

In the lower mold 2 shown in Fig. 4(b) and Fig. 5(b), in the lower cull block 220 of the lower die chess 22, one lower cull section sensor 230 is provided on the front side of the lower cull block 220 near the center, and one is provided on the rear side of the lower cull block 220 near the center. In the lower mold 2 shown in Fig. 4(b) and Fig. 5(b), the lower cull block 220 has a plurality of pots 250 into which resin materials such as resin tablets are respectively poured. Each of the above-mentioned plurality of cull sections 124 is provided corresponding to two pots 250 of the plurality of pots 250 having different combinations, and resin materials are supplied to each cull section 124 from these two pots 250. Between the pots 250 facing each other in the left-right direction, the above-mentioned lower cull section heater 240 is arranged.

The resin sealing mold M of the resin sealing device S is equipped with a control unit, and the control unit has a temperature control area that controls the temperature. This temperature control area is called the temperature control unit.

As shown in FIG. 6, the control unit 30 includes an execution unit 31 that executes heating by the heating means. The execution unit 31 includes a calculation unit 32 and a heating execution unit 33. The calculation unit 32 calculates the heating adjustment content for one molding operation by the heating means until the molding operation after the previous one is executed based on information on temperature changes acquired by the temperature measurement means in the molding operation before the previous one. The heating execution unit 33 executes heating by the heating means in the molding operation after the previous one based on the adjustment content calculated by the calculation unit 32. The heating execution unit 33 includes a temperature control unit 34 and a heating instruction unit 35 that instructs the temperature control unit 34 on the adjustment content of heating by the heating means.

A temperature control area is also set in the resin sealing mold M. A sensor and a heater are provided in this temperature control area. The sensor here refers to any one of the upper die set sensor 110, upper cull section sensor 130, upper cavity sensor 131, lower die set sensor 210, lower cull section sensor 230, and lower cavity sensor 231 described above. The heater here refers to any one of the upper die set heater 111, upper cull section heater 140, upper cavity heater 141, lower die set heater 211, lower cull section heater 240, and lower cavity heater 241 described above.

The sensor and heater installed in this temperature adjustment area are connected to the temperature control unit 34 shown in FIG. 6. The temperature control unit 34 acquires information on temperature changes in the temperature adjustment area from the sensor installed in the temperature adjustment area during the molding operation in which the resin sealing device S resin seals the semiconductor element. Here, one molding operation is the operation from when the molded product is clamped by the upper mold 1 and the lower mold 2 in the resin sealing device S to when the clamping of the molded product by the upper mold 1 and the lower mold 2 is released. The molded product is a member before resin sealing by the resin sealing device S, that is, a member in which a semiconductor element that has not been resin sealed is placed on a substrate. Also, the molded product is a member after resin sealing by the resin sealing device S, that is, a member in which a resin-sealed semiconductor element is placed on a substrate.

The calculation unit 32 of the execution unit 31 shown in FIG. 6 also acquires information on temperature changes in the temperature adjustment area from a sensor installed in the temperature adjustment area via the temperature control unit 34 of the heating execution unit 33.

The calculation unit 32 predicts the temperature change in the temperature adjustment area when the next molding operation is performed from the information on the temperature change in the temperature adjustment area acquired by the sensor during the molding operation, and calculates the numerical values of various parameters. These various parameters are various information for adjusting the heating by the heater so that the temperature adjustment area reaches the desired temperature, and include, for example, information for controlling the ON/OFF of the upper cull heater 140. These various parameters are an example of the adjustment contents of the heating in one molding operation by the heating means. Below, the numerical values of the parameters calculated by the calculation unit 32 may be simply referred to as parameters.

The desired temperature here means a temperature that is set appropriately depending on the type of resin sealing mold, the type of base material, the type of resin, etc. Details of the various parameters related to heating by the heater will be described later.

The heating instruction unit 35 of the heating execution unit 33 instructs the temperature control unit 34 on the values of the various parameters calculated by the calculation unit 32. The temperature control unit 34 controls the heater based on the various parameters instructed by the heating instruction unit 35.

More specifically, the temperature control unit 34 adjusts the output of the heater that heats the temperature adjustment area, adjusts the heating time, and adjusts the timing at which heating starts based on various parameters instructed by the heating instruction unit 35, and performs predictive control so that the temperature adjustment area reaches the desired temperature.

Note that predictive control is defined as follows. First, a reference temperature for the molding operation is set in the resin sealing mold. Then, based on information on the temperature change in the temperature adjustment area measured in advance, it is calculated how much heat (or how little heat) should be applied to reduce the temperature difference between the reference temperature in that temperature adjustment area, and changes are made to the output, heating time, and timing of starting heating for the heater that heats the temperature adjustment area. In this way, predictive control is achieved by changing various parameters related to heating in subsequent molding operations based on information on the temperature change measured in advance, thereby controlling the heating of the heater so that the temperature difference between the temperature adjustment area and the reference temperature is reduced during the next molding operation.

Here, the number of temperature control units 34 set in the control unit 30 is not limited to one, and multiple temperature control units 34 can be set.

Next, we will explain the resin sealing method performed using the above-mentioned resin sealing device S. Note that the following content is an example of the resin sealing method according to the present invention.

[Calculation of various parameters used in predictive control]
First, in the resin sealing method using the resin sealing apparatus S, the execution unit 31 of the control unit 30 shown in FIG. 6 calculates various parameters for the next molding operation by the pre-molding method shown in FIG. 7(a).

Here, we will explain an example in which the upper cull block 120 is set as the temperature adjustment area for predictive control. That is, we will explain how to calculate various parameters that are required when the execution unit 31 of the control unit 30 controls the upper cull part heater 140 to perform predictive control.

In this pre-molding method, the substrate and resin to be encapsulated are supplied to the resin encapsulation device S, and normal molding is performed to encapsulate the semiconductor element (see FIG. 7(a)). In this normal molding, the upper cull section heater 140 is turned on for a given period of time to perform the molding operation (step S1). The upper cull section sensor 130 executes an acquisition process to acquire information on the temperature change of the upper cull block 120 during the period in which the molding operation of step S1 is performed.

Next, from the results of the normal molding described above, the calculation unit 32 of the execution unit 31 calculates various parameters related to heating of the upper cull heater 140 so that the upper cull block 120 will reach the desired temperature when the next molding operation is performed (step S2). That is, from the information on the temperature change in the upper cull block 120 acquired by the upper cull sensor 130 during normal molding, the temperature change in the upper cull block 120 when the next molding operation is performed is predicted, and various parameters are calculated. In this way, the processing of step S2 includes a calculation process that calculates the heating adjustment content for one molding operation by the heating means performed in the execution process of the next molding operation based on the information on the temperature change measured by the upper cull sensor 130 in the molding operation before the previous one. The next molding operation is a molding operation that follows the previous molding operation and is performed after the previous molding operation, and may be referred to as the current molding operation below.

Here, the various parameters calculated by the calculation unit 32 include, for example, information for controlling the ON/OFF of the upper cull section heater 140. Note that FIG. 7(b) shows a conceptual diagram of the state in which the various parameters are reflected in the ON/OFF control of the upper cull section heater 140.

Specifically, there is information on the "delay before heater ON (X0)," which is the time from the start of the molding operation until the upper cull heater 140 is turned ON, and the "total heater ON/OFF time (Xall)," which is the time from turning the upper cull heater 140 ON until it is finally turned OFF.

In addition, when the upper cull section heater 140 is switched ON and OFF between when it is turned ON and when it is finally turned OFF, there is information on the time (X1 to X4) that the upper cull section heater 140 is turned ON each time.

In addition, although not indicated by symbols in FIG. 7(b), the time for which the upper cull section heater 140 is turned OFF and the number of times the upper cull section heater 140 is switched ON and OFF are also included as information on various parameters.

In this way, normal molding is performed with the resin sealing device S, and based on the information on the temperature change of the upper cull block 120 acquired during the molding operation, the calculation unit 32 of the execution unit 31 can automatically calculate various parameters (X0, X1, X2, X3, X4, etc.) that control the ON/OFF of the upper cull section heater 140 when performing the next molding operation based on the information on the temperature change of the upper cull block 120 acquired during the molding operation. The heating execution unit 33 executes an execution process that performs heating by the upper cull section heater 140 during the next molding operation based on the numerical values of the various parameters (X0 to X4, etc.) calculated by the calculation unit 32.

By calculating the heating start time (X0) and using this as a reference, it is possible to adjust the timing of the start of heating relative to the start of the molding operation in various ways. Also, by calculating the total heater ON/OFF time (Xall), it is possible to adjust the length of time for heating in various ways.

The types of parameters described here are merely examples, and the contents of the parameters related to the ON/OFF control of the upper cull heater 140 are not limited to these. For example, the number of ON/OFF controls of the upper cull heater 140 is not limited to four times, but may be less than three times, or may be five times or more. The execution unit 31 of the control unit 30 can also change the number of ON/OFF controls of the upper cull heater 140 based on information on the temperature change measured by the upper cull sensor 130 in the molding operation prior to the previous one.

Here, the method of adjusting the temperature of the upper cull block 120 will be described in more detail with reference to Figures 8 to 11. In Figures 8 to 11, "t1" is the start time of one molding operation, and is the time when the molded product is clamped between the upper mold 1 and the lower mold 2. "t10" is the end time of one molding operation, and is the time when the clamping of the molded product by the upper mold 1 and the lower mold 2 is released. "Tmax" is the upper limit of the required temperature (hereinafter referred to as the upper limit temperature), and "Tmin" is the lower limit of the required temperature (hereinafter referred to as the lower limit temperature). For ease of explanation, the molding operation that was the subject of the measurement of the temperature changes shown in Figures 8 to 11 will be referred to as the previous molding operation. 8 to 11, for ease of explanation, the parameters used in the previous molding operation are referred to as the parameters used in the previous molding operation (X0 _1-4 to X4 _1-4 ), and the parameters used in the next molding operation are referred to as the parameters to be used in the next molding operation (X0 _1-4 ' to X4 _1-4 '). Furthermore, the total heater ON/OFF time in the previous molding operation is referred to as the previous heater ON/OFF total time (Xall ₁ to Xall ₄ ), and the total heater ON/OFF time in the next molding operation is referred to as the next heater ON/OFF total time (Xall ₁ ' to Xall ₄ ').

In the first example shown in FIG. 8(a), in the previous molding operation, the temperature of the upper cull block 120 drops from time t2 to time t3, then rises, exceeds the upper limit temperature Tmax at time t4, and continues to exceed the upper limit temperature Tmax until the end time t10. The temperature of the upper cull block 120 changes as shown in FIG. 8(a) mainly because the upper cull section heater 140 is turned on for an excessively long time.

Therefore, the calculation unit 32 of the execution unit 31 shown in Fig. 6 calculates various parameters so that the ON time of the upper cull portion heater 140 in the next molding operation is shorter than that in the previous molding operation. Specifically, the calculation unit 32 calculates parameters ( _X11 ' to X41') to be used in the next molding operation so that the total time that the upper cull portion heater 140 is ON is shorter than that in the previous molding operation. Then, the heating execution unit 33 of the execution unit 31 controls the ON/OFF of the cull portion heater 140 in the next molding operation using the parameters ( _X11 ' to _X44 ') to be used in _the next molding operation. The ON/OFF of the cull portion heater 140 is an example of heating by a heating means.

For example, in the example shown in FIG. 8(b), the calculation unit 32 calculates the parameters (X1 ₁ ' to X4 ₁ ') to be used in the next molding operation so that the total time that the upper cull portion heater 140 is turned on is shorter than that of the previous molding operation. In this case, the calculation unit 32 can delete the parameter (X4 ₁ ') to be used in the next molding operation by setting the value of the parameter (X4 ₁ ') to be used in the next molding operation to zero. The calculation unit 32 can also calculate the parameter (X0 1 ') to be used in the next molding operation so that the time from the start of the molding operation to turning on the upper cull portion heater ₁₄₀ in the next molding operation is shorter than that of the previous molding operation.

In the second example shown in FIG. 9(a), in the previous molding operation, the temperature of the upper cull block 120 drops, falls below the lower limit temperature Tmin at time t3, and remains below the lower limit temperature Tmin until the end time t10. The temperature of the upper cull block 120 changes as shown in FIG. 9(a) mainly because the upper cull section heater 140 is turned on for too short a time.

Therefore, the calculation unit 32 of the execution unit 31 shown in Fig. 6 calculates various parameters so that the ON time of the upper cull portion heater 140 in the next molding operation is longer than in the previous molding operation. Specifically, the calculation unit 32 calculates parameters (X1 ₂ ' to X4 2') to be used in the next molding operation so that the total time that the upper cull portion heater 140 is ON is longer than in the previous molding operation. Then, the heating execution unit 33 of the execution unit 31 controls the ON/OFF of the cull portion heater 140 in the next molding operation using the parameters (X1 ₂ ' to X4 ₂ ') to be used in _the next molding operation.

For example, in the example shown in FIG. 9(b), the calculation unit 32 calculates parameters (X1 ₂ to X4 ₂ ') to be used in the next molding operation so that the total time that the upper cull portion heater 140 is turned on is longer than in the previous molding operation. In this case, the calculation unit 32 can add a parameter (X5 ₂ ') to be used in the next molding operation. The parameter (X5 ₂ ') to be used in the next molding operation is a parameter indicating the time that the upper cull portion heater 140 is turned on for the fifth time. The calculation unit 32 can also calculate a parameter (X0 ₂ ') to be used in the next molding operation so that the time from the start of the molding operation to turning on the upper cull portion heater 140 in the next molding operation is longer than in the previous molding operation.

In the third example shown in FIG. 10(a), in the previous molding operation, the temperature of the upper cull block 120 rises, exceeds the upper limit temperature Tmax at time t4, falls below the upper limit temperature Tmax at time t5, and remains at the required temperature until the end time t10. The reason why the temperature of the upper cull block 120 changes as shown in FIG. 10(a) is mainly because the time from the start of the molding operation to turning on the upper cull section heater 140 is short.

Therefore, as shown in Fig. 10(b), the calculation unit 32 of the execution unit 31 shown in Fig. 6 calculates the parameters (X0 3 ') to be used in the next molding operation so that the time from the start of the molding operation to turning on the upper cull portion heater 140 in the next molding operation is longer than that in the previous molding operation. Then, the heating execution unit 33 of the execution unit 31 controls the ON/OFF of the cull portion heater 140 in the next molding operation using the parameters (X0 ₃ ', X1 ₃ ' to X4 ₃ ') to be used in the next molding operation. The parameters (X1 ₃ ' to X4 ₃ ') to be used in the next molding operation may be the same as the parameters (X1 ₃ to X4 ₃ ) used in the previous molding operation _, or may be different from the parameters (X1 ₃ to X4 ₃ ) used in the previous molding operation. For example, the calculation unit 32 can further calculate parameters (X1 ₃ ' to X4 3 ') to be used in the next molding operation so that the total time that the upper cullet heater 140 is turned on is shorter than that of _the previous molding operation.

In the fourth example shown in FIG. 11(a), in the previous molding operation, the temperature of the upper cull block 120 drops, falls below the lower limit temperature Tmin at time t6, then exceeds the lower limit temperature Tmin at time t7, and remains at the required temperature until the end time t10. The reason why the temperature of the upper cull block 120 changes as shown in FIG. 11(a) is mainly because it takes a long time from the start of the molding operation to turning on the upper cull section heater 140.

Therefore, as shown in Fig. 11(b), the calculation unit 32 of the execution unit 31 shown in Fig. 6 calculates a parameter (X0 4 ') to be used in the next molding operation so that the time from the start of the molding operation to turning on the upper cull portion heater 140 in the next molding operation is shorter than that in the previous molding operation. Then, the heating execution unit 33 of the execution unit 31 controls the ON/OFF of the cull portion heater 140 in the next molding operation using the parameters (X0 ₄ ', X1 ₄ ' to X4 ₄ ') to be used in the next molding operation. The parameters (X1 ₄ ' to X4 ₄ ') to be used in the next molding operation may be the same as the parameters (X1 ₄ to X4 ₄ ) used in the previous molding operation _, or may be different from the parameters (X1 ₄ to X4 ₄ ) used in the previous molding operation. For example, the calculation unit 32 can further calculate parameters (X1 ₄ ' to X4 4 ') to be used in the next molding operation so that the total time that the upper cullet heater 140 is turned on is longer than that of _the previous molding operation.

The calculation unit 32 can also calculate various parameters (X0 to X4, etc.) by raising the lower limit temperature Tmin and lowering the upper limit temperature Tmax each time a preset number of molding operations are performed. This allows the resin sealing device S to reduce the temperature change of the upper cull block 120 during the current molding operation by repeatedly performing the molding operation.

In the above example, the calculation unit 32 changes the parameters (X0 to X4, etc.) when the temperature exceeds the upper limit temperature Tmax or falls below the lower limit temperature Tmin, but is not limited to this example.

For example, the calculation unit 32 can calculate the numerical values of various parameters to be used in the next molding operation using a computational model generated by machine learning. The computational model generated by machine learning is a neural network such as a convolutional neural network.

Such a calculation model is, for example, a calculation model that inputs information on the temperature change of the upper cull block 120 measured by the upper cull sensor 130 during one molding operation and outputs numerical values of parameters (X0 to X4, etc.). Before performing the next molding operation, the calculation unit 32 uses the calculation model to calculate the numerical values of the parameters (X0 to X4, etc.). Specifically, before performing the next molding operation, the calculation unit 32 inputs information on the temperature change of the upper cull block 120 measured by the upper cull sensor 130 during the previous molding operation into the calculation model, thereby obtaining the numerical values of the parameters (X0 to X4, etc.) output from the calculation model as the calculation results. The heating instruction unit 35 instructs the temperature control unit 34 on the numerical values of the parameters (X0 to X4, etc.) calculated by the calculation model in the calculation unit 32 during the next molding operation.

The control unit 30 may also include a learning unit that generates a computational model by machine learning. In this case, the learning unit may generate a computational model by machine learning based on the values of various parameters used in the previous or previous operation and information on the temperature change of the upper cull block 120 measured by the upper cull section sensor 130 in the previous or previous operation. For example, the learning unit determines a molding operation in which the temperature change of the upper cull block 120 measured by the upper cull section sensor 130 is within a preset temperature range as a learning molding operation. Then, the learning unit generates a computational model using a data set that includes, for each learning molding operation, a combination of the temperature change of the upper cull block 120 measured by the upper cull section sensor 130 in the learning molding operation and the parameters (X0, X1 to X4) used in the execution process in the learning molding operation.

For example, the learning unit generates a calculation model so that the sum of the differences between the numerical values of the parameters (X0, X1 to X4) obtained by inputting information on the temperature change of the upper cull block 120 measured by the upper cull sensor 130 during the learning molding operation into the calculation model and the numerical values of the parameters (X0, X1 to X4) used in the execution process of the learning molding operation is minimized.

The preset temperature range that is the condition for the temperature range in the learning molding operation is, for example, a temperature range from an upper limit temperature Tmax to a lower limit temperature Tmin, but it may also be a temperature range from a temperature lower than the upper limit temperature Tmax to a temperature higher than the lower limit temperature Tmin. The learning unit can also determine all molding operations as learning molding operations.

The calculation model may be a recurrent neural network instead of a convolutional neural network. In this case, the calculation model configured with a recurrent neural network is, for example, a calculation model that inputs information on the temperature change of the upper cull block 120 measured by the upper cull portion sensor 130 in each of multiple consecutive molding operations and outputs numerical values of parameters (X0 to X4, etc.). Before performing the next molding operation, the calculation unit 32 inputs information on the temperature change of the upper cull block 120 measured by the upper cull portion sensor 130 in each of multiple consecutive molding operations before the previous one into the calculation model, and obtains the numerical values of the parameters (X0 to X4, etc.) output from the calculation model by arithmetic processing. The heating instruction unit 35 instructs the temperature control unit 34 on the numerical values of the parameters (X0 to X4, etc.) calculated by the calculation model in the calculation unit 32 in the next molding operation. Similar to the computational model composed of a convolutional neural network, the learning unit can also generate a computational model composed of a recurrent neural network by machine learning based on the values of various parameters used in the previous or previous time and information on the temperature change of the upper cull block 120 measured by the upper cull sensor 130 in the previous or previous time.

The computational model generated by machine learning is not limited to a neural network, but may be, for example, a computational model generated by a learning algorithm such as linear regression or logistic regression, or may be a computational model such as a support vector machine.

In the above example, the heating by the heating means in the current molding operation is adjusted based on the adjustment content calculated in the calculation process without using information on the temperature of the cull block measured by the upper cull part sensor 130 in the current molding operation, but the method of adjusting the heating by the heating means is not limited to this example. The temperature control unit 34 of the heating execution unit 33 can also correct the adjustment content calculated in the calculation process based on information on the temperature of the cull block measured by the upper cull part sensor 130 in the current molding operation, and execute an execution process to perform heating by the heating means in the current molding operation based on the corrected adjustment content. The information on the temperature of the cull block measured by the upper cull part sensor 130 is information on the instantaneous value of the temperature of the cull block measured by the upper cull part sensor 130, but it may also be information on the temperature change of the cull block measured by the upper cull part sensor 130 in the molding operation before the previous one.

For example, the execution unit 31 of the control unit 30 calculates parameters (X0 to X4, etc.) based on the temperature information measured by the upper cull section sensor 130 in the previous or previous molding operation, and in the next molding operation, while controlling the upper cull section sensor 130 with the calculated parameter values (X0 to X4, etc.), if the temperature of the upper cull block 120 measured by the upper cull section sensor 130 satisfies a predetermined condition, the parameter values (X0 to X4, etc.) can be corrected in real time. The predetermined condition is, for example, when the temperature change per unit time exceeds a predetermined value or falls outside a predetermined range.

[On the effectiveness of predictive control]
Next, the effectiveness of the execution unit 31 of the control unit 30 shown in Figure 6 predicting and controlling the temperature of the upper cullet block 120 using various parameters calculated by the calculation unit 32 will be explained with reference to Figures 12 and 13 below.

Here, we performed continuous molding operations to resin-encapsulate semiconductor elements using resin encapsulation device S, and compared the results of molding operations without predictive control (first molding) (Figure 12(a)), molding operations with predictive control (second molding) (Figure 12(b)), and molding operations with predictive control (third molding) (Figure 12(c)).

In addition, for the second molding, the execution unit 31 calculates various parameters from the molding operation of the first molding and performs predictive control. In addition, for the third molding, the execution unit 31 calculates various parameters from the molding operation of the second molding and performs predictive control.

Graphs of the temperature change of the upper cull block 120 during each molding operation are shown in Figures 12(a) to 12(c). Note that Figure 12(a) shows the results of the first molding run, Figure 12(b) shows the results of the second molding run, and Figure 12(c) shows the results of the third molding run. The mold temperature was set to 182°C.

As shown in FIG. 12(a), in a molding operation without predictive control (first molding), the temperature of the upper cull block 120 was at its lowest, approximately 5.3°C lower than the mold set temperature of 182°C. In addition, after the resin sealing was completed, the temperature of the upper cull block 120 was approximately 6.9°C higher than the mold set temperature of 182°C.

Also, as shown in FIG. 12(b), in the molding operation (second molding) using predictive control, the temperature of the upper cull block 120 was at its lowest, about 4°C lower than the mold set temperature of 182°C. Also, after the resin sealing was completed, the temperature of the upper cull block 120 was about 1.5°C higher than the mold set temperature of 182°C.

Also, as shown in FIG. 12(c), in the molding operation (third molding) with predictive control, the temperature of the upper cull block 120 was at its lowest, approximately 3.6°C lower than the mold set temperature of 182°C. Also, after the resin sealing was completed, the temperature of the upper cull block 120 was approximately 2°C higher than the mold set temperature of 182°C.

Comparing the results of Figure 12(a) and Figure 12(b), the tendency for the temperature of the upper cull block 120 to decrease after resin sealing was mitigated in the molding operation with predictive control (second molding) compared to the molding operation without predictive control (first molding).

In addition, when comparing the results of Figure 12 (b) and Figure 12 (c), the tendency for the temperature of the upper cull block 120 to decrease after resin sealing was further mitigated in the molding operation with predictive control (third molding) compared to the molding operation with predictive control (second molding).

Comparing the results of FIG. 12(a) with those of FIG. 12(b) and FIG. 12(c), the tendency for the temperature of the upper cull block 120 to rise after resin sealing was mitigated in the molding operations with predictive control (second and third moldings) compared to the molding operation without predictive control (first molding).

In the fourth and subsequent molding operations, the execution unit 31 calculates various parameters from the previous molding operation and performs predictive control. The graph shown in FIG. 13 is a graph obtained by plotting the lowest and highest temperatures of the upper cull block 120 in each molding operation and connecting the plotted positions. In FIG. 13, the horizontal axis indicates time [sec] and the vertical axis indicates temperature [°C]. As shown in FIG. 13, in the fourth and subsequent molding operations, the temperature change of the upper cull block 120 is smaller than in the molding operations before the third. Note that the example shown in FIG. 13 shows a case where the upper limit temperature is 180°C and the lower limit temperature is 170°C.

As is clear from the results shown in Figures 12(a) to 12(c) and 13, the execution unit 31 shown in Figure 6 uses various parameters calculated by the calculation unit 32 based on information about the temperature change of the upper cull block 120 in the previous molding operation, and the temperature control unit 34 controls the upper cull portion heater 140 in the next molding operation, making it possible to control the temperature of the upper cull block 120 with high accuracy. In other words, the effectiveness of predictive control using various parameters calculated by the calculation unit 32 in the control unit 30 was confirmed. By predictive control of the cull block temperature, the mold temperature around the cull portion decreases, preventing the resin in the cull portion from sticking to the mold (cull portion).

The temperature control unit 34 shown in FIG. 6 controls the temperature of the upper cull block 120 in the first molding operation using various preset parameters (hereinafter referred to as initial parameters). The initial parameters can be set to the same values as the various parameters used in the first molding operation performed by the resin sealing device S that produces the same or similar molded product, for example. This makes it easy to set the initial parameters.

In addition, when the resin sealing device S is operated on a daily basis, the calculation unit 32 can calculate the difference between the temperature change of the upper cull block 120 in the first molding operation on the previous day and the temperature change of the upper cull block 120 in the first molding operation on the current day. When the difference from the temperature change of the upper cull block 120 is within a preset range, the calculation unit 32 can set the various parameters used in the second molding operation on the previous day as the various parameters used in the second molding operation on the current day. In addition, when the difference from the temperature change of the upper cull block 120 is not within a preset range, the calculation unit 32 can calculate the various parameters used in the second molding operation on the current day by adjusting the various parameters used in the second molding operation on the previous day based on the difference from the temperature change of the upper cull block 120. The calculation unit 32 can also calculate the various parameters used in the third molding operation in the same manner as the various parameters used in the second molding operation.

In addition, in the above-mentioned example, the execution unit 31 of the control unit 30 controls the upper cull section heater 140 based on information on temperature changes in the upper cull block 120 acquired by the upper cull section sensor 130, but temperature adjustment of the cull block is not limited to such an example. The execution unit 31 can adjust the temperature of the cull block by controlling at least one of the upper cull section heater 140, the upper cavity heater 141, the lower cull section heater 240, and the lower cavity heater 241 based on information on temperature changes acquired by at least one of the upper cull section sensor 130 and the lower cull section sensor 230.

In the above example, an example of adjusting the temperature of the cull block was described, but the execution unit 31 of the control unit 30 can also adjust the temperature of the cavity block in addition to or instead of adjusting the temperature of the cull block. For example, the execution unit 31 can adjust the temperature of the cavity block by controlling at least one of the upper cull section heater 140, the upper cavity heater 141, the lower cull section heater 240, and the lower cavity heater 241.

Next, we will explain an example of a method for controlling the temperature of a resin sealing mold.

Using Figures 14(a) and 14(b), we will explain a method for controlling the temperature of a resin sealing mold by setting multiple temperature control units 34 in the control unit 30 for the resin sealing device S.

In this method, a total of nine temperature control areas A1 to A9 are set in the upper cull block 120 and the left and right upper cavity blocks 121 of the upper mold 1 (see Figure 14 (b)).

More specifically, in the upper cavity block 120, three temperature control areas, A4, A5, and A6, are set in the front-to-rear direction. In addition, in the upper cavity blocks 121 on the left and right, three temperature control areas, A1, A2, and A3, and A7, A8, and A9, are set on each side in the front-to-rear direction.

In addition, an upper cull sensor 130 is disposed in the temperature adjustment areas A4 to A6. In addition, an upper cavity sensor 131 is disposed in the temperature adjustment areas A1 to A3 and the temperature adjustment areas A7 to A9.

Although not shown, the control unit 30 is configured with a plurality of temperature control units 34. Each temperature control unit 34 is connected to a sensor and a heater provided in one temperature adjustment area, and the temperature control unit 34 controls the connected heater based on information on various parameters instructed by the heating instruction unit 35 of the control unit 30.

In this method, similar to the above-mentioned pre-molding method for the upper cull block 120 (see FIG. 12(a)), normal molding is performed to resin-encapsulate the semiconductor element using a resin encapsulation device S. Then, for the temperature adjustment areas A1 to A9, the upper cull sensor 130 and the upper cavity sensor 131 acquire information on the temperature changes. The calculation unit 32 of the control unit 30 acquires the information on the temperature changes via the temperature control unit 34 and calculates various parameters for the temperature adjustment areas A1 to A9.

Then, based on the various parameter information for the temperature adjustment areas A1 to A9 calculated from normal molding, a molding operation (first time) is performed in which predictive control is performed individually for the temperature adjustment areas A1 to A9 (step S1). During the molding operation of step S1, an acquisition process is performed to acquire information on temperature changes in the temperature adjustment areas A1 to A9 using the upper cull portion sensor 130 and the upper cavity sensor 131.

Next, based on the information on the temperature change of each of the temperature adjustment areas A1 to A9 acquired in the first molding operation in step S1, the calculation unit 32 calculates the contents of each of the various parameters in one molding operation. The contents of the various parameters used for predictive control in the molding operation in step S1 are then changed to the contents calculated by the calculation unit 32, and the heating instruction unit 35 instructs each of the temperature control units 34 on the contents of the changed various parameters (step S2). This aims to further stabilize the temperature of each of the temperature adjustment areas A1 to A9 in the second and subsequent molding operations. The process of calculating the contents of the various parameters is an example of a calculation process that calculates the adjustment contents of heating in one molding operation by the heating means executed in the execution process of the next molding operation.

Next, based on the contents of the various parameters for one molding operation calculated by the calculation unit 32 in step S2, each temperature control unit 34, which has received instructions from the heating instruction unit 35, controls the connected heaters to perform a molding operation (second or later) that performs predictive control in the temperature adjustment areas A1 to A9 (step S3). The processing of the temperature control unit 34 in step S3 is an example of an execution process that performs heating for the temperature adjustment areas A1 to A9 based on the adjustment contents of heating by the heating means calculated in the calculation process.

After step S3, if the next molding operation is "yes", the process returns to step S2 again, and the calculation unit 32 calculates various parameters for each temperature adjustment area based on the information on the temperature change in each temperature adjustment area A1 to A9 acquired in the previous molding operation. The heating instruction unit 35 then changes the various parameters based on the content calculated by the calculation unit 32 and instructs each temperature control unit 34. In other words, the calculation of various parameters and the control of each heater by the temperature control unit 34 based on this calculation are repeated.

Also, after step S3, if there is no next molding operation, the series of steps ends (step S5).

In this way, when molding operations are performed continuously, the contents of various parameters used for predictive control of the next molding operation can be modified based on the information on the temperature changes in temperature adjustment areas A1 to A9 obtained in the previous molding operation, allowing for highly accurate temperature control so that the temperature adjustment areas A1 to A9 approach the desired temperature.

In addition, in this method, multiple temperature control units 34 are set in the control unit 30, and one temperature control unit 34 is connected to a sensor and heater provided in one temperature adjustment area, so that the temperature control unit 34 can adjust the heating by the heater in accordance with temperature changes in each temperature adjustment area. This makes it possible to perform temperature control with even higher precision for the entire upper mold 1.

Here, the number of temperature control regions set in the upper cull block 120 and the left and right upper cavity blocks 121 in the upper mold 1 is not limited to nine, and can be changed as appropriate.

In addition, the structure is not necessarily limited to one in which multiple temperature control regions are set in the upper mold 1, and multiple temperature control regions can also be set in the lower mold 2. Furthermore, multiple temperature control regions can also be set in both the upper mold 1 and the lower mold 2.

Next, using Figures 15(a) and 15(b), we will explain a method for controlling the temperature of the resin sealing mold by setting one temperature control unit 34 in the control unit 30 for the resin sealing device S.

In this method, a total of nine temperature control areas, including temperature control area A and temperature control areas B1 to B8, are set in the upper cull block 120 and the left and right upper cavity blocks 121 of the upper mold 1 (see Figure 15 (b)).

More specifically, in the upper cavity block 120, three temperature adjustment areas are set in the front-to-rear direction: temperature adjustment area A and temperature adjustment areas B4 and B5. In addition, in the left and right upper cavity blocks 121, three temperature adjustment areas are set on each side in the front-to-rear direction: B1, B2, and B3, and B6, B7, and B8.

In addition, an upper cull sensor 130 is disposed in temperature adjustment area A and temperature adjustment areas B4 and B5. In addition, an upper cavity sensor 131 is disposed in temperature adjustment areas B1 to B3 and temperature adjustment areas B6 to B8.

Although not shown, the control unit 30 is also configured with one temperature control unit 34. This temperature control unit 34 is connected to the upper cull portion sensor 130 and the upper cull portion heater 140 provided in the temperature adjustment area A. The temperature control unit 34 also controls the connected upper cull portion heater 140 based on information on various parameters instructed by the heating instruction unit 35.

Although not shown, the control unit 30 is connected to each sensor and heater provided in the temperature adjustment areas B1 to B8. The control unit 30 is also configured to change the output ratio of each heater provided in the temperature adjustment areas B1 to B8.

In this method, similar to the above-mentioned pre-molding method for the upper cull block 120 (see FIG. 7(a)), normal molding is performed to resin-encapsulate the semiconductor element using a resin encapsulation device S. Then, for the temperature adjustment area A, the upper cull sensor 130 acquires information on temperature changes. The calculation unit 32 of the control unit 30 acquires the information on the temperature changes via the temperature control unit 34 and calculates various parameters.

Then, based on the various parameter information in temperature adjustment area A calculated from normal molding, a molding operation (first time) is performed in which predictive control is performed in temperature adjustment area A and temperature adjustment areas B1 to B8 (step S1). In this molding operation in step S1, the output of each heater in temperature adjustment areas B1 to B8 is set to the same output as the heater in temperature adjustment area A, and heating is performed by the heaters.

During the molding operation of step S1, the upper cull sensor 130 acquires information on temperature changes and various parameters for temperature adjustment area A. In addition, an acquisition process is performed for temperature adjustment areas B1 to B8, in which the upper cull sensor 130 and upper cavity sensor 131 acquire information on temperature changes.

Next, although not shown, the calculation unit 32 calculates the contents of various parameters based on the information on the temperature change in the temperature adjustment area A acquired in the molding operation of step S1. The calculation unit 32 then changes the various parameters based on the contents calculated, and the heating instruction unit 35 instructs the temperature control unit 34 on the various parameters changed by the calculation unit 32. This aims to further stabilize the temperature in the temperature adjustment area A. The process of calculating the contents of various parameters is an example of a calculation process that calculates the adjustment contents of heating in one molding operation by the heating means executed in the execution process of the next molding operation.

Based on the information on the temperature changes in temperature adjustment areas A and B1 to B8 acquired during the molding operation in step S1, the calculation unit 32 calculates the temperature difference between the temperature of temperature adjustment area A and the temperatures of temperature adjustment areas B1 to B8 (step S2). Based on this temperature difference information and the information on the output of the upper cull heater 140 instructed by the heating instruction unit 35 to the temperature control unit 34, the calculation unit 32 calculates the output, time, and timing of each heater in temperature adjustment areas B1 to B8 so that the ratio of the output of each heater in temperature adjustment areas B1 to B8 changes. The heating instruction unit 35 instructs the temperature control unit 34 on the output, time, and timing of each heater in temperature adjustment areas B1 to B8 calculated by the calculation unit 32. As a result, the temperature of temperature adjustment area A and the temperature of temperature adjustment areas B1 to B8 are adjusted to the temperature adjustment areas B1 to B8.

For example, when the temperature of temperature adjustment area B1 is higher than the temperature of temperature adjustment area A, the calculation unit 32 reduces the proportion of heater output for temperature adjustment area B1 based on the temperature difference.

More specifically, the calculation unit 32 makes a small change to the output ratio of the upper culvert heater 140 instructed by the heating instruction unit 35 to the temperature control unit 34 based on the temperature difference between the temperature adjustment areas, and sets this as the output value of the upper cavity heater 141 provided in the temperature adjustment area B1.

This reduces the temperature difference between temperature control area A and temperature control areas B1 to B8 in the next molding operation, stabilizing the temperature in temperature control areas B1 to B8.

Next, the execution unit 31 executes a molding operation (from the second time onward) that performs predictive control in the temperature adjustment areas A and B1 to B8 using the output ratio of each heater set in step S2 (step S3). The processing of the temperature control unit 34 in step S3 is an example of an execution process that executes heating for the temperature adjustment areas A and B1 to B8 based on the adjustment content of heating by the heating means calculated in the calculation process.

After step S3, if the next molding operation is "yes", the process returns to step S2 again, and the calculation unit 32 calculates the contents of various parameters based on the information on the temperature change in temperature adjustment area A acquired in the previous molding operation. The heating instruction unit 35 then changes the various parameters based on the contents calculated by the calculation unit 32 and instructs the temperature control unit 34. That is, for temperature adjustment area A, the calculation of various parameters and the control of the upper cull heater 140 by the temperature control unit 34 based on this calculation are repeatedly performed.

The calculation unit 32 also changes the output ratio of each heater in the temperature adjustment areas B1 to B8 based on the information on the temperature changes in the temperature adjustment areas A and B1 to B8 acquired in the previous molding operation and the information on the output of the upper cull heater 140 instructed by the heating instruction unit 35 to the temperature control unit 34. That is, for the temperature adjustment areas B1 to B8, the output ratio of each heater is changed based on the temperature difference between the temperature adjustment areas B1 to B8 and the temperature adjustment area A, and the temperature control unit 34 controls each heater based on this change, repeatedly.

Also, after step S3, if there is no next molding operation, the series of steps ends (step S5).

In this way, when molding operations are performed continuously, this method allows for highly accurate temperature control by correcting the output ratio of each heater in temperature adjustment areas B1 to B8 based on the information on the temperature changes in temperature adjustment areas A and B1 to B8 obtained in the previous molding operation, so that temperature adjustment areas A and B1 to B8 approach the desired temperature.

In addition, in this method, when controlling the temperatures of the temperature adjustment regions B1 to B8, it is sufficient to set one temperature control unit 34 in the control unit 30 and predict the temperature change in the temperature adjustment region A. Therefore, compared to a structure in which multiple temperature control units 34 are set in the control unit 30, this method allows for highly accurate temperature control of the temperature of the upper mold 1 with a simpler structure.

Here, the sensor and heater provided in the temperature adjustment area A do not necessarily need to be connected to the temperature control unit 34, and a structure in which a sensor and heater provided in another temperature adjustment area are connected to the temperature control unit 34 may also be adopted. In addition, the number of temperature control units 34 set in the control unit 30 does not necessarily need to be limited to one, and two or more temperature control units 34 may be set in the control unit 30 as necessary.

In addition, the number of temperature control regions set in the upper cull block 120 and the left and right upper cavity blocks 121 in the upper mold 1 is not limited to nine, and can be changed as appropriate.

In addition, the structure is not necessarily limited to one in which multiple temperature control regions are set in the upper mold 1, and multiple temperature control regions can also be set in the lower mold 2. Furthermore, multiple temperature control regions can also be set in both the upper mold 1 and the lower mold 2.

As described above, the resin sealing method of the first embodiment of the present invention makes it possible to control the temperature of the mold with high precision when sealing a semiconductor element placed on a substrate with resin. Furthermore, the resin sealing mold of the first embodiment of the present invention makes it possible to control the temperature of the mold with high precision when sealing a semiconductor element placed on a substrate with resin.

The terms and expressions used in this specification and claims are merely explanatory and are not limiting in any way, and are not intended to exclude terms and expressions equivalent to the features described in this specification and claims or parts thereof. It goes without saying that various modifications are possible within the scope of the technical concept of the present invention.

S Resin sealing device M Resin sealing mold 1 Upper mold 30 Control unit 31 Execution unit 32 Calculation unit 33 Heating execution unit 34 Temperature control unit 35 Heating instruction unit 11 Upper mold die set 110 Upper die set sensor 111 Upper die set heater 12 Upper mold chess 120 Upper cull block 121 Upper cavity block 122 First upper holder base 123 Second upper holder base 124 Cull unit 130 Upper cull unit sensor 131 Upper cavity sensor 140 Upper cull unit heater 141 Upper cavity heater 2 Lower mold 21 Lower mold die set 210 Lower die set sensor 211 Lower die set heater 22 Lower mold chess 220 Lower cull block 221 Lower cavity block 222 First lower holder base 223 Second lower holder base 230 Lower cull section sensor 231 Lower cavity sensor 240 Lower cull section heater 241 Lower cavity heater

Claims (10)

A resin sealing method for performing a resin sealing operation multiple times using a resin sealing mold having a mold body provided with a cull block having a cull portion configured with a depression that forms a cull, which is a resin supply path, and a cavity block that forms a cavity, a temperature measuring means that measures the temperature of at least one of the cull block and the cavity block, and a heating means that heats at least one of the cull block and the cavity block, the method comprising the steps of:
an acquiring step of acquiring information on a temperature change of at least one of the cull block and the cavity block during each of the plurality of molding operations by the temperature measuring means;
a calculation step of calculating an adjustment content of heating in one molding operation by the heating means until a molding operation subsequent to the previous molding operation is performed, based on the information of the temperature change acquired in the acquisition step in the molding operation prior to the previous molding operation among the plurality of molding operations;
an execution step of executing heating by the heating means in a molding operation subsequent to the previous molding operation based on the adjustment content calculated in the calculation step. The execution step includes:
The resin sealing method according to claim 1, characterized in that heating is performed by the heating means in the molding operation subsequent to the previous one based on the adjustment content calculated in the calculation process, without using information on the temperature measured by the temperature measuring means in the molding operation subsequent to the previous one. The calculation step includes:
3. The resin sealing method according to claim 1, wherein at least one of an output, a time, and a timing of heating by the heating means is calculated as the adjustment. The calculation step includes:
The resin sealing method according to any one of claims 1 to 3, characterized in that the adjustment content of the heating by the heating means is calculated using a computational model generated by machine learning, the computational model having as input temperature change information, which is information on the temperature change acquired in the acquisition process in the molding operation before the previous one, and having as output adjustment content information, which is information on the adjustment content of the heating by the heating means. The resin sealing method according to claim 4 , further comprising a learning step of generating the calculation model based on the temperature change information and the adjustment content information. The cull block and the cavity block have:
A plurality of temperature control regions are set in which the temperature measurement means and the heating means can individually perform temperature measurement and heating,
The calculation step includes:
6. The resin sealing method according to claim 1, further comprising calculating an output, time and timing of heating by said heating means for each of said plurality of temperature adjustment regions. the plurality of temperature adjustment regions include at least a first temperature adjustment region and a second temperature adjustment region different from the first temperature adjustment region,
The calculation step includes:
The resin sealing method according to claim 6, characterized in that the heating output, time and timing by the heating means corresponding to the second temperature control area are calculated based on information on the relative temperatures of the first temperature control area and the second temperature control area in the molding operation before the previous one and information on the temperature change of the first temperature control area. The calculation step includes:
The resin sealing method according to claim 6, further comprising the step of calculating, for each of the plurality of temperature adjustment regions, a heating output, a time and a timing of the heating by the heating means in the molding operation subsequent to the previous molding operation, based on the information on the temperature change. The said Calblock is
A plurality of the cull portions are formed,
The temperature measuring means is
The resin sealing method according to any one of claims 1 to 8, further comprising a sensor for measuring a temperature between a plurality of the cull portions of the cull block. A resin sealing mold comprising: a mold body provided with a cull block having a cull portion configured with a depression that forms a cull, which is a resin supply path, and a cavity block that forms a cavity; a temperature measuring means for measuring the temperature of at least one of the cull block and the cavity block; a heating means for heating at least one of the cull block and the cavity block; and an execution unit for executing heating by the heating means, wherein an operation of resin-sealing a semiconductor element placed on a substrate is counted as one molding operation, and the mold body performs multiple molding operations by repeating the operation,
The temperature measuring means is
acquiring information on temperature changes of at least one of the cull block and the cavity block during each of the multiple molding operations;
The execution unit is
a calculation unit that calculates adjustments to heating in one molding operation by the heating means based on information on temperature changes acquired by the temperature measurement means in a molding operation prior to the previous one among the multiple molding operations, until a molding operation subsequent to the previous one is performed, and a heating execution unit that executes heating by the heating means in the molding operation subsequent to the previous one based on the adjustments calculated by the calculation unit.

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