JP2013187351A - Resin sealing device, resin used in resin sealing device, molding, and resin sealing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the strength of a molding and reduce the occurence of chip cracks in a semiconductor chip.SOLUTION: A resin sealing device 100 includes: an upper mold 110; a lower mold 130 moving close to and away from the upper mold 110; a driving part 145 moving the lower mold 130; and a control part 146 controlling the driving of the driving part 145. The resin sealing device performs resin seals on a substrate 106, on which semiconductor chips 107 are mounted, in a cavity 150 formed between the upper mold 110 and the lower mold 130. In the resin sealing device 100, the control part 146 drives the driving part 145 to cause the lower mold 130 to move close to the upper mold 110 and brings surfaces 107B of the semiconductor chips 107, which are opposite to the substrate side, in contact with a surface of the cavity 150.

Description

  The present invention relates to a resin sealing device, a resin used for the resin sealing device, a molded product, and a resin sealing method.

  As shown in Patent Document 1, a semiconductor chip is flip-chip bonded to a substrate in order to increase the density and size of the substrate on which the semiconductor chip is mounted. And the connection part of a semiconductor chip and a board | substrate is filled with the underfill material in order to avoid a fracture | rupture.

JP 2011-171426 A

  However, even when an underfill material as disclosed in Patent Document 1 is provided, chip cracks may occur in the semiconductor chip when handling a flip-chip bonded substrate (molded product).

  Accordingly, the present invention has been made to solve the above-described problems, and is a resin sealing device capable of improving the strength of a molded product and reducing the occurrence of chip cracks in a semiconductor chip, and a resin used in the resin sealing device. It is an object to provide a molded product and a resin sealing method.

  The present invention includes a fixed mold, a movable mold that can move toward and away from the fixed mold, a drive unit that moves the movable mold, and a control unit that controls the drive of the drive unit. In the resin sealing device that performs resin sealing of a substrate on which a semiconductor chip is mounted in a cavity formed between the fixed mold and the movable mold, the control unit drives the driving unit. The above-described problem is solved by bringing the movable mold closer to the fixed mold and bringing the surface of the cavity opposite to the substrate side into contact with the surface of the cavity.

  That is, in the present invention, when the resin is sealed, the surface of the cavity on the side opposite to the substrate is in contact with the surface of the cavity.

  The present invention includes a fixed mold, a movable mold that can be moved toward and away from the fixed mold, a drive unit that moves the movable mold, and a control unit that controls the drive of the drive unit. A molded product molded by a resin sealing device that performs resin sealing of a substrate on which a semiconductor chip is mounted in a cavity formed between the fixed mold and the movable mold, It can also be regarded as a molded product characterized in that the surface of the semiconductor chip opposite to the substrate side is exposed.

  Alternatively, the present invention includes a fixed mold, a movable mold that can move toward and away from the fixed mold, a drive unit that moves the movable mold, and a control unit that controls the drive of the drive unit. In the resin sealing method for performing resin sealing of a substrate on which a semiconductor chip is mounted in a cavity formed between the fixed mold and the movable mold, the driving unit is driven by the control unit Thus, the method can be regarded as a resin sealing method including a step of bringing the movable mold closer to the fixed mold and bringing the surface of the cavity on the opposite side of the semiconductor chip into contact with the surface of the cavity.

  ADVANTAGE OF THE INVENTION According to this invention, it is possible to improve the intensity | strength of a molded article and to reduce generation | occurrence | production of the chip crack of a semiconductor chip.

Schematic diagram of a resin sealing device to which an example of an embodiment of the present invention is applied Schematic diagram showing the substrate used in the resin sealing device Schematic diagram showing an example of resin used in a resin sealing device Schematic diagram showing another example of resin used in a resin sealing device Schematic diagram showing resin sealing procedure

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic view of a resin sealing device to which an example of an embodiment of the present invention is applied. First, a schematic resin sealing device, a release film, a substrate, a semiconductor chip, and a resin will be described below.

  As shown in FIGS. 1 and 2, the resin sealing device 100 moves the upper mold 110 (fixed mold), the lower mold 130 (movable mold) that can approach and leave the upper mold 110, and the lower mold 130. A drive unit 145 for controlling the drive of the drive unit 145, and a cavity 150 formed between the upper mold 110 and the lower mold 130 of the substrate 106 on which the semiconductor chip 107 is mounted. Resin sealing is performed. Here, the control unit 146 drives the driving unit 145 to bring the lower mold 130 closer to the upper mold 110, and the surface of the cavity 150, that is, the surface 132 A of the compression mold 132 via the release film 104, The non-substrate side surface 107B is brought into contact.

  The resin sealing device 100 is disposed on the surface of the lower mold 130 (the surface 132A of the compression mold 132), which is a mold on the surface opposite to the substrate of the semiconductor chip 107, and forms a mold for forming the surface of the cavity 150. A film 104 is provided. The release film 104 has elasticity and is supplied to the surface of the lower mold 130 in a continuous state. In this case, the used release film 104 can be easily collected. Further, the release film 104 may be used as a transport mechanism for the resin 108. Note that the release film 104 may have a strip-like form, or the release film itself may not be used.

  Further, as shown in FIG. 2, the substrate 106 is, for example, a glass epoxy substrate (may be a lead frame), and a plurality of semiconductor chips 107 are mounted on one surface, and this is a region where resin sealing is performed. It is said that. Solder bumps are formed on the input / output terminals of the semiconductor chip 107, and the input / output terminals of the semiconductor chip 107 are bonded to the electrode terminals of the substrate 106, that is, flip-chip bonding or face-down bonding (that is, semiconductor chip). 107 is the substrate side surface 107A). For this reason, there are no input / output terminals or electrodes and circuit patterns for wire bonding on the non-substrate side surface 107B of the semiconductor chip 107, and the anti-substrate side surface 107B has a flat shape.

  As shown in FIGS. 3 and 4, the resin 108 has a flat plate shape, and a through hole 109 into which the semiconductor chip 107 can be fitted is provided at a position corresponding to the semiconductor chip 107. 3A and 4A are top views of the resin, and FIGS. 3B and 4B are side sectional views of the resin. More specifically, the inner width W2 of the through hole 109 is set larger than the width W1 of the semiconductor chip 107. The thickness H2 of the resin 108 and the height H1 of the semiconductor chip 107 from the surface of the substrate 106 (of course, including the widths W1 and W2) are the number of semiconductor chips 107 to be resin-sealed and the resin sealing. In consideration of the region where the resin is formed, it is appropriately determined when the resin 108 is molded so that the surface 107B opposite to the substrate 107 of the semiconductor chip 107 is exposed after the resin sealing. As shown in FIG. 3, the resin 108 may be provided with a through-hole 109 after a flat plate-shaped resin 108A is preliminarily molded. Alternatively, as shown in FIG. 4, the resin 108 may be provided with the through hole 109 after preliminarily molding the resin 108 </ b> B provided with the recess 108 </ b> BA at the position of the through hole 109. Of course, the resin 108 provided with the through hole 109 may be directly molded. Note that the chip detection of the semiconductor chip 107 is performed before the substrate 106 is attracted to the upper mold 110, and as a result, the through hole 109 is not provided in the resin 108 for the portion where the semiconductor chip 107 is not provided. Yes.

  Hereinafter, the configuration of the resin sealing device 100 will be described in detail.

  As shown in FIG. 1, the resin sealing device 100 includes a fixed upper mold 110 and a movable lower mold 130. The upper mold may be a movable mold and the lower mold may be a fixed mold. The resin sealing device 100 of the present embodiment is a compression mold in which the resin 108 for resin sealing is directly supplied to the cavity 150, but the resin is introduced into the cavity via the cull part and the runner part. The present invention may be applied to a transfer type resin sealing device.

  A substrate suction path (not shown) is formed inside the upper mold 110, whereby the substrate 106 is sucked and held. Further, a heater (not shown) is provided inside the upper mold 110 so as to have a predetermined temperature. In addition, the board | substrate does not need to be adsorb | sucked to an upper mold | type, and the release film may be adsorbed instead.

  The lower mold 130 includes a compression mold 132 and a frame mold 136 as shown in FIG. The compression mold 132 supports the frame mold 136 via the spring 138. The compression mold 132 is provided with a heater (not shown) so as to have a predetermined temperature. A through hole 136A is formed in the frame mold 136, and a compression mold 132 is fitted therein. Therefore, the frame mold 136 is movable in the Z direction with respect to the compression mold 132. A film suction path (not shown) is formed in the lower mold 130, and the release film 104 is sucked onto the surface of the lower mold 130 by the negative pressure generated by a suction mechanism (not shown) through the film suction path. be able to. In addition, you may make it adsorb | suck a board | substrate to the surface of a lower mold | type.

  A load cell 140 (pressure detector) is provided on the lower surface of the lower mold 130. The load cell 140 can detect a pressure that changes as the upper mold 110 and the lower mold 130 approach each other.

  The drive unit 145 includes a ball screw 141, a belt 142, a motor 143, and an encoder 144. The ball screw 141 is connected to the lower mold 130 via the load cell 140. The ball screw 141 is rotatable by a pulley 143B provided on the output shaft 143A of the motor 143 and a belt 142 applied to the pulley 143B. That is, the lower mold 130 can be moved in the Z direction by the motor 143. The motor 143 includes an encoder 144 (distance detection unit). The encoder 144 counts the number of rotations of the motor 143, and the number of rotations of the motor 143 is proportional to the moving distance of the lower mold 130 relative to the fixed upper mold 110. That is, it can be said that the encoder 144 can detect the relative distance between the two molds when the upper mold 110 and the lower mold 130 approach each other.

  In addition, the resin sealing device 100 includes a control unit 146 that controls the drive unit 145. The calculation part of the control unit 146 takes in pressure information detected by the load cell 140 at a predetermined timing. At the same time, the calculation part captures distance information detected by the encoder 144. The storage portion of the control unit 146 can store pressure information and distance information as necessary. The setting portion of the control unit 146 can perform various settings. In the present embodiment, the clamping condition under which the anti-substrate side surface 107B of the semiconductor chip 107 is exposed (for example, the thickness of the cavity 150 is equal to or less than the thickness from the anti-substrate side surface 107B of the semiconductor chip 107 to the anti-semiconductor chip side surface 106A of the substrate 106). Normal distance information and normal pressure information (collectively referred to as normal sealing conditions) are stored in the storage portion. The storage portion may store the distance information and the pressure information obtained at the time of the mold clamping where the anti-substrate side surface 107B of the semiconductor chip 107 is exposed previously as normal distance information and normal pressure information. Alternatively, the storage portion may store the distance information and pressure information input from the setting portion as normal distance information and normal pressure information.

  Next, a resin sealing procedure by the resin sealing device 100 will be described with reference to FIG.

  First, in the mold open state in which the upper mold 110 and the lower mold 130 are separated (FIG. 5A), the substrate 106 on which the semiconductor chip 107 is mounted is brought close to the upper mold 110 by a transport mechanism (not shown). At this time, a suction mechanism (not shown) is operated to adsorb the substrate 106 to the upper mold 110. At the same time, the release film 104 is arranged on the lower mold 130 in a continuous state by a film transport mechanism (not shown), the suction mechanism (not shown) is operated, and the release film 104 is adsorbed to the lower mold 130. Then, the resin 108 is transported by a resin transport mechanism (not shown), and the resin 108 is put into the cavity 150. At this time, the resin 108 is disposed so that the semiconductor chip 107 can be inserted into the through hole 109 of the resin 108. In this state, the upper mold 110 and the lower mold 130 are set to a constant temperature (for example, 175 degrees) for resin sealing (FIG. 5B).

  Next, the control unit 146 drives the drive unit 145 to bring the lower mold 130 closer to the upper mold 110. Then, the upper mold 110 and the frame mold 136 come into contact with each other via the substrate 106 and the release film 104, and the release film 104 and the substrate 106 are fixed. The upper mold 110 and the lower mold 130 form a sealed state. At this time, the cavity 150 formed between the upper mold 110 and the lower mold 130 is decompressed by a decompression mechanism (not shown), and the inside of the cavity 150 is in a vacuum state (FIG. 5C).

  Further, the upper mold 110 and the lower mold 130 are brought closer to each other. Then, the surface 107 B of the semiconductor chip 107 is brought into contact with the surface of the cavity 150. Then, based on the pressure information detected by the load cell 140, in a state where the inside of the cavity 150 is at a predetermined pressure (matched with the normal pressure information within an allowable range), the mold is clamped to perform resin sealing (FIG. 5 ( D)). That is, the control unit 146 positions the lower mold 130 with respect to the upper mold 110 so that the thickness of the cavity 150 is equal to or less than the thickness from the anti-substrate side surface 107B of the semiconductor chip 107 to the anti-semiconductor chip side surface 106A of the substrate 106. Control. At this time, the control unit 146 presses the anti-substrate side surface 107 </ b> B of the semiconductor chip 107 against the surface of the cavity 150. Therefore, the part 104A of the release film 104 existing on the surface 107B opposite to the substrate of the semiconductor chip 107 is greatly compressed and deformed in the Z direction as compared with the part 104B of the release film 104 without the other semiconductor chip 107. That is, in the cavity 150, the portion 104A of the release film 104 is most compressed and deformed. Note that in order to apply pressure to the resin 108 in a vacuum state, the space between the semiconductor chip 107 and the substrate 106 is filled with resin. Then, the resin sealing of the substrate 106 is performed in a state where pressure is applied from the outside, not simply filled with resin. For this reason, the resin-sealed substrate 106 (molded product) can be in a state of being clogged with resin, so that generation of voids and unfilling can be avoided and the strength of the molded product can be improved. .

  The molded product obtained by mold clamping is in a form in which at least the surface 107B opposite to the substrate of the semiconductor chip 107 is exposed. The determination of this state is based on the normal sealing condition stored by the control unit 146. Done. The control unit 146 reads the normal sealing condition stored in the storage portion, matches the pressure information detected by the current load cell 140 with the normal pressure information within an allowable range, and detects the pressure information by the load cell 140. Then, the distance information detected by the encoder 144 is compared with the normal distance information.

  If the current distance information is outside the allowable range of the normal distance information, the control unit 146 determines that the current resin sealing is abnormal, stops mold clamping, and performs mold opening (stop command). And the control part 146 gives the instruction | indication, such as inspection of a metal mold | die, the board | substrate 106, resin 108, and the release film 104, with a speaker and a display which are not shown in figure. Even if the distance information detected by the encoder 144 exceeds the normal distance information, if the inside of the cavity 150 does not reach a predetermined pressure, a stop command is similarly issued from the control unit 146.

  If the current distance information is within the allowable range of the normal distance information, the mold clamping is performed until a predetermined time elapses when the mold clamping ends. Then, after a predetermined time has elapsed, the upper mold 110 and the lower mold 130 are opened. Then, the substrate 106 (molded product) sealed with a resin by a transport mechanism (not shown) is taken out from the upper mold 110. The allowable range is determined in consideration of variations in the substrate 106 on which the semiconductor chip 107 is mounted, variations in the resin 108, and the like.

  In the present embodiment, the molten resin 108 is pushed and spread in the process in which the upper mold 110 and the lower mold 130 are brought close to each other and the inside of the cavity 150 becomes a predetermined pressure. However, the gap between the anti-substrate side surface 107B of the semiconductor chip 107 and the cavity 150 disappears before the molten resin 108 covers the anti-substrate side surface 107B of the semiconductor chip 107. That is, during resin sealing, the surface of the cavity 150 is in contact with the surface 107B of the semiconductor chip 107 opposite to the substrate. In addition, the control unit 146 presses the anti-substrate side surface 107 </ b> B of the semiconductor chip 107 against the surface of the cavity 150. For this reason, it is possible to sufficiently prevent the resin 108 from entering the anti-substrate side surface 107B of the semiconductor chip 107 (note that the controller does not necessarily press the anti-substrate side surface of the semiconductor chip against the surface of the cavity. Also good).

  Further, in the present embodiment, a release film 104 that is disposed on the surface 132A of the compression mold 132 of the lower mold 130 on the surface opposite to the substrate side of the semiconductor chip 107 and forms the surface of the cavity 150 is provided. For this reason, the possibility that the surface of the lower mold 130 is soiled with the resin 108 can be avoided, and the molded product after the resin sealing can be easily peeled off.

  In this embodiment, the encoder 144 that can detect the relative distance between the upper mold 110 and the lower mold 130 when the upper mold 110 and the lower mold 130 approach each other, and the pressure that changes depending on the approach of the upper mold 110 and the lower mold 130 can be detected. The control unit 146 determines the state of the molded product based on the distance information detected by the encoder 144 and the pressure information detected by the load cell 140. For this reason, it is possible to stably confirm whether or not resin sealing has been normally performed before the mold opening by the upper mold 110 and the lower mold 130. That is, for example, a step of taking out the molded product after opening the mold and inspecting the abnormality of the resin sealing can be made unnecessary. The pressure information detected by the load cell 140 is matched with the normal pressure information within an allowable range, and the distance information detected by the encoder 144 is compared with the normal distance information. Conversely, the pressure information detected by the encoder 144 is detected. The distance information may be matched with the normal distance information within an allowable range, and the pressure information detected by the load cell 140 may be compared with the normal pressure information to determine the state of the molded product. Of course, the load cell and the encoder do not have to be indispensable configurations.

  In the present embodiment, the control unit 146 controls the upper mold 110 so that the thickness of the cavity 150 is equal to or less than the thickness from the anti-substrate side surface 107B of the semiconductor chip 107 to the anti-semiconductor chip side surface 106A of the substrate 106. Although the position of the lower mold 130 is controlled, such a configuration is not necessarily required.

  In the present embodiment, the resin 108 has a flat plate shape, and a through hole 109 into which the semiconductor chip 107 can be fitted is provided at a position corresponding to the semiconductor chip 107. For this reason, fluctuations in the amount of resin used for resin sealing can be reduced and the management thereof is easy, but the transport of the resin 108, the positioning of the resin 108 in the cavity 150, and the placement of the resin 108 can be easily performed. . The resin does not have to be in such a form. For example, the resin may be rod-shaped, individual, granular, powdery, liquid, or a combination thereof, and the surface of the cavity on the side opposite to the substrate side of the semiconductor chip The resin may be poured into the cavity while avoiding the cavity portion at a position corresponding to the semiconductor chip so that the resin is sealed in a state where the resin contacts.

  That is, according to this embodiment, it is possible to improve the strength of the molded product and reduce the occurrence of chip cracks in the semiconductor chip 107. For example, by stably exposing the surface 107B of the semiconductor chip 107 opposite to the substrate from the resin, it becomes possible to directly cool the semiconductor chip 107 that becomes high temperature by the operation, thereby extending the life of the molded product and stable operation. This can be useful for preventing performance degradation due to heat.

  Although the present invention has been described with reference to the present embodiment, the present invention is not limited to the present embodiment. That is, it goes without saying that improvements and design changes can be made without departing from the scope of the present invention.

  The resin sealing device, the resin used for the resin sealing device, the molded product, and the resin sealing method of the present invention can be used for the purpose of resin sealing by exposing the surface opposite to the substrate of the semiconductor chip from the resin. .

DESCRIPTION OF SYMBOLS 100 ... Resin sealing apparatus 104 ... Release film 106 ... Substrate 106A ... Anti-semiconductor chip side surface 107 ... Semiconductor chip 107A ... Substrate side surface 107B ... Anti-substrate side surface 108, 108A, 108B ... Resin 109 ... Through-hole 110 ... Top Mold 130 ... Lower mold 132 ... Compression mold 132A ... Compression mold surface 136 ... Frame mold 136A ... Through hole 138 ... Spring 140 ... Load cell 141 ... Ball screw 142 ... Belt 143 ... Motor 144 ... Encoder 145 ... Drive unit 146 ... Control unit 150 ... cavity

Claims (8)

A fixed mold; a movable mold that can move toward and away from the fixed mold; a drive unit that moves the movable mold; and a control unit that controls driving of the drive unit. In a resin sealing device that performs resin sealing of a substrate on which a semiconductor chip is mounted in a cavity formed between a mold and the movable mold,
The control unit drives the driving unit to bring the movable mold closer to the fixed mold, and contacts the surface of the cavity opposite to the substrate side with the surface of the cavity. . In claim 1,
The said control part presses the surface opposite to the board | substrate of the said semiconductor chip against the surface of the said cavity. The resin sealing apparatus characterized by the above-mentioned. In claim 1 or 2,
A resin seal comprising a release film disposed on a surface of a mold on the surface opposite to the substrate side of the semiconductor chip of the fixed mold and the movable mold, and forming a surface of the cavity. apparatus. In any one of Claims 1 thru | or 3,
A distance detection unit capable of detecting the relative distance between the two molds when the fixed mold and the movable mold approach each other;
A pressure detection unit capable of detecting a pressure that changes due to the approach of the fixed mold and the movable mold,
The control unit determines a state of the substrate after resin sealing based on distance information detected by the distance detection unit and pressure information detected by the pressure detection unit. Stop device. In any one of Claims 1 thru | or 4,
The control unit controls the position of the movable mold with respect to the fixed mold so that the thickness of the cavity is equal to or less than the thickness from the surface of the semiconductor chip opposite to the substrate to the surface of the substrate opposite to the semiconductor chip. A resin sealing device. A resin used in the resin sealing device according to claim 1,
A resin having a flat plate shape, and a through hole into which the semiconductor chip can be fitted is provided at a position corresponding to the semiconductor chip. A fixed mold; a movable mold that can move toward and away from the fixed mold; a drive unit that moves the movable mold; and a control unit that controls driving of the drive unit. A molded product molded by a resin sealing device that performs resin sealing of a substrate on which a semiconductor chip is mounted in a cavity formed between a mold and the movable mold,
A molded product characterized in that at least the surface of the semiconductor chip opposite to the substrate is exposed. A fixed mold, a movable mold that can be moved toward and away from the fixed mold, a drive unit that moves the movable mold, and a control unit that controls the drive of the drive unit, and the fixed mold. In a resin sealing method for performing resin sealing of a substrate on which a semiconductor chip is mounted in a cavity formed between a mold and the movable mold,
A step of causing the control unit to drive the driving unit to bring the movable mold closer to the fixed mold and to bring the surface of the semiconductor chip opposite to the substrate side into contact with the surface of the cavity. Sealing method.

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