KR20110120237A

KR20110120237A - Resin sealing apparatus and resin sealing method

Info

Publication number: KR20110120237A
Application number: KR1020110039379A
Authority: KR
Inventors: 류타 고노
Original assignee: 스미도모쥬기가이고교 가부시키가이샤
Priority date: 2010-04-28
Filing date: 2011-04-27
Publication date: 2011-11-03
Also published as: JP2011230423A; TWI452654B; CN102233639B; JP5490605B2; KR101230403B1; TW201208010A; CN102233639A

Abstract

PURPOSE: A resin sealing apparatus and resin sealing method is provided that amount of resin little, or the resin sealing thickness thins. Even in that case, avoid defects in sealing the resin. CONSTITUTION: A resin sealing apparatus arranged the semiconductor chips to the cavity of the mold with the resin. The resin sealing apparatus decompresses and heats the mold, the compressive pressure is added to the semiconductor chip and the resin is hermetically sealed. A driving velocity(V5) from a minimum velocity switch position(Y5) to an acceleration position(Y6) to the acceleration position most slows in the shaped body of the mold from the dead slow switching position. A driving velocity(V6) to a pressure holding position(Y7) fasts from a first touch position(Y3) from a driving velocity(V3) to a low-velocity switch position(Y4), and the low-velocity switch position from a dead slow switch position(V4) to the dead slow switching position, and the acceleration position from the dead slow switching position than the driving rate to the acceleration position.

Description

Resin sealing apparatus and resin sealing method

This application claims priority based on Japanese Patent Application No. 2010-104382, filed April 28, 2010. The entire contents of that application are incorporated by reference in this specification.

The present invention relates to the technical field of a resin sealing device and a resin sealing method.

In patent document 1, the to-be-molded product (semiconductor chip and the bonding wire accompanying it) mounted on the board | substrate is arrange | positioned with a thermosetting resin in the cavity of a metal mold | die, and the pressure reduction of the metal mold | die is carried out. A resin sealing device is proposed in which a resin is sealed by heating and applying a compression pressure to the molded article. Here, this resin sealing apparatus has the metal mold | die which has a 1st metal mold | die and the 2nd metal mold | die which is relatively accessible and spaced with respect to this 1st metal mold | die.

Here, the thermosetting resin has a flat plate shape (solid). For this reason, this resin softens once from solid by heating, becomes a low viscosity liquid, hardens | cures, and returns to a solid. That is, the resin sealing device is such that the movement of the mold in mold clamping is completed within a time (called gel time) from when the resin is changed from solid to liquid and returned to solid again. Controlled.

[Patent Document 1] Japanese Unexamined Patent Publication No. 2005-186439

However, in the resin sealing device shown in Patent Document 1, for example, when the bonding wire of a molded article is thin, when the resin sealing is performed under conventional control with respect to a small amount of resin, the following problems arise. Found. That is, when resin sealing is carried out with a thin resin sealing thickness, the deformation amount of a bonding wire becomes large and a resin sealing defect may arise.

Therefore, in order to reduce the pressure of the resin applied to the bonding wire, the inventor slows the driving speed (approaching speed) of the second mold relative to the first mold at the time of sealing the resin as the distance between them becomes shorter, The sealing of the resin was tested by carrying out the shape of. And even then, the movement of the mold was completed within the gel time. However, even when such control was performed, resin sealing defects occurred. At the same time, a problem has arisen that the time for resin sealing becomes long.

Accordingly, the present invention has been made to solve the above problems, and the resin sealing device and the resin which can avoid the resin sealing failure even when the resin sealing thickness is small, the amount of resin is thin, and also shorten the time for resin sealing It is a problem to provide a sealing method.

The present invention has a mold having a first mold and a second mold relatively accessible to and spaced apart from the first mold by a driving source, and the molded article mounted on the substrate together with the thermosetting resin, the cavity of the mold. In the resin sealing device, which is placed in the mold, and the resin is sealed by decompressing and heating the mold and applying compression pressure to the molded article, the thickness of the substrate and the molded article, respectively. The index position by the drive source of the second mold with respect to the first mold corresponding to the distance between the surface of the first mold and the surface of the second mold constituting the cavity corresponds to the sum of the resin sealing thicknesses. The second gold for this first mold, which is in the reference position and is immediately contacted with the resin and the molded article being in non-contact, with the resin and the molded article being disposed and heated in the first mold and the second mold, respectively. This first index position of the first mold, which is closer than the first position with respect to the first mold, is farther than the reference position, and is immediately before the compression pressure starts (rises up). The index of the second mold with respect to the first mold, wherein the index position of the second mold with respect to the mold is the second position, closer to the reference position with respect to the first mold, and immediately after the compression pressure is started. The index position of the second mold with respect to the first mold, wherein the position is the third position, is closer to the first mold than the reference position, and the compression pressure is the maximum compression pressure applied to the molded object. The fourth position, the driving speed by the drive source of the second mold relative to the first mold from the second position to the third position is the slowest in the shape of the mold Together with this drive speed from the first position to this second position and this drive speed from this third position to the fourth position are faster than this drive speed from this second position to this third position. By providing a control means, the said subject is solved.

This invention puts new discovery knowledge into the analysis of the viscosity change of a thermosetting resin, and changes the drive speed of the 2nd metal mold | die with respect to the 1st metal mold | die at the time of resin sealing in steps. This new discovery knowledge is explained below using Fig. 3B.

In FIG. 3 (B), the state of change in the viscosity (Vs) of the resin with respect to the time t when the thermosetting resin (also referred to simply as resin) is heated for a predetermined time is schematically shown. The graph which shows the viscosity of resin originally estimated by the inventor is shown by Gv. In this case, even if the driving speed of the second mold with respect to the first mold is slowed down as the distance between them becomes shorter, the resin maintains a low viscosity in a wide range BR of the gel time Tg. It is thought that the sealing failure can also be avoided. However, from the inventor's new discovery knowledge, the graph showing the viscosity of the resin is assumed to be Gv1. That is, even within the gel time Tg, the region of low viscosity of the resin is narrow, so that the lowest viscosity state of the resin comes at an early timing in the first half of the gel time. And the resin is that the viscosity gradually rises from the time point tv at which the resin becomes the minimum, and curing proceeds. For this reason, it is thought that only by slowing the driving speed, the load on the bonding wire becomes large due to the effect of the increase in the viscosity of the resin, resulting in a resin sealing defect. In particular, the thinning of the bonding wires also greatly affects the slight increase in the viscosity of the resin.

For this reason, the present invention is intended to complete the movement of the mold in the mold at the earliest possible time in the gel time Tg, i.e., while the thermosetting resin has a viscosity as low as possible even if the driving speed is slowed down. Doing.

Specifically, the present invention specifies the fourth position from the reference position and the first position with respect to the position of the second mold relative to the first mold (index position due to the driving source), respectively. The driving speed from the second position immediately before the compression pressure is started to the third position immediately after the compression pressure is started is the slowest in the mold body. At the same time, the driving speed from the first position just before contacting the resin and the molded article to this second position and the driving speed from the third position to the fourth position at which the compression pressure becomes the maximum compression pressure are obtained from the second position to the third. It is faster than the driving speed to the position.

That is, the present invention slows the driving speed in the mold of the mold only when the compression pressure is started. In particular, immediately after the compression pressure is started, the driving speed is increased as opposed to the conventional idea, so that the movement of the mold in the mold can be completed while the viscosity of the resin is low. For this reason, by such a synergistic effect, the influence which a thermosetting resin substantially has on a to-be-molded product (phosphorus bonding wire, for example) is minimized. That is, even when the resin sealing thickness with a small amount of resin is thin, a resin sealing defect can be avoided. At the same time, the time for resin sealing can be shortened.

However, the specific parameter regarding the "indicator position" by the drive source for specifying the position of the second mold with respect to the first mold is not particularly limited. However, if the index position by the drive source is obtained from, for example, the position (rotation speed) determined by the rotary encoder mounted on the rotation drive source, the reproducible index position can be obtained at low cost. have.

Here, the driving speed from the third position to the fourth position is faster than the driving speed from the second position to the third position, but is not particularly limited numerically. However, for example, the driving speed from the third position to the fourth position may be three times or more of the driving speed from the second position to the third position. In this case, the completion time of movement of the mold in the mold can be made faster than before, and the resin sealing defect can be avoided and the time for resin sealing can be shortened more than before. Alternatively, the drive speed from the second position to the third position may be numerically converted to a maximum of 0.2 mm / sec in terms of an approach speed at no load from the second mold to the first mold. In addition, the driving speed from the third position to the fourth position may be 1 mm / sec or more in terms of the approach speed at no load.

However, in the case where the compression pressure in the third position is between 1 MPa and 2 MPa, even if there is a practical error in the amount of resin, while the driving speed from the second position to the third position is the slowest, It is possible to spread the resin approximately throughout the cavity. For this reason, the resin sealing defect can be most stably avoided while shortening the time of resin sealing.

Here, the distance between the surface of the said 1st metal mold | die and the surface of the said 2nd metal mold | die calculated | required from the index position by the said drive source in the said 1st position is a sum of the value of 4 times or more of the thickness of the said board | substrate and the said resin sealing thickness. It is more preferable to become. However, this figure does not necessarily require exactness.

However, further, the control means sets the index position between the first position and the second position to the fifth position, and sets the driving speed from the fifth position to the second position from the third position to the fourth position. When it is slower than the said drive speed to a position, when a part (for example, a part of bonding wire etc.) of a to-be-molded product is in contact with resin in a 2nd position, it becomes possible to slow the drive speed to reach it. That is, the influence which a thermosetting resin has on a to-be-molded product can further be reduced, and generation | occurrence | production of resin sealing defect can be reduced more.

Here, the distance between the surface of the said 1st metal mold | die and the surface of the said 2nd metal mold | die calculated | required from the index position by the said drive source in the said 5th position is a sum of the value of 1.8 times or more of the thickness of the said board | substrate and the said resin sealing thickness. It is preferable to become. However, this figure does not necessarily require exactness.

Here, the time until the said metal mold | die is heated to predetermined | prescribed temperature, and the said metal mold | die moves to the said 3rd position after the resin is mounted in the said cavity is 20 times of the gel time of the said resin in said temperature. When it is between 40% and 40%, even if the resin is in a solid state, the compression pressure can be started by softening and melting to make the viscosity of the resin low. At the same time, it is possible to reliably shorten the movement of the mold in the mold body compared with the prior art, thereby making it possible to avoid further resin sealing defects and to shorten the time for resin sealing.

Here, this invention uses the metal mold | die provided with the 1st metal mold | die and the 2nd metal mold | die which is relatively accessible and spaced apart with respect to this 1st metal mold | die by a drive source, The said molded object mounted on the board | substrate with the said thermosetting resin is said, In the resin sealing method of arranging in the cavity of a metal mold | die, performing pressure reduction and heating of the metal mold, and sealing the resin by applying a compression pressure to the to-be-molded product, respectively, the sum of the thickness of the said board | substrate and the resin sealing thickness of the said to-be-molded product said The resin and the molded article are referred to as an index position by the drive source of the second mold with respect to the first mold corresponding to the distance between the surface of the first mold and the surface of the second mold constituting the cavity. The index position of the second mold relative to the first mold which is disposed on the first mold and the second mold and heated, and the resin and the molded article are in contact with each other and immediately before contact. Is the first position, and the index position of the second mold relative to the first mold, which is closer to the first mold than the first position but farther than the reference position and immediately before the compression pressure is started, is set to the second position. The index position of the second mold with respect to the first mold, which is closer to the reference position with respect to the first mold and immediately after the compression pressure is started, is set as the third position, and with respect to the first mold. The index position of the second mold relative to the first mold, which is closer than the reference position and the compression pressure is the maximum compression pressure applied to the molded object, is set as the fourth position, and the third position from the second position. A step of slowing the driving speed of the second mold relative to the first mold in the furnace by the driving source in the mold of the mold; and from the first position to the second position. And a driving speed of the driving speed and the driving speed from the third position to the fourth position is faster than the driving speed from the second position to the third position. You can also see.

According to the present invention, even when the resin sealing thickness with a small amount of resin is thin, the resin sealing defect can be avoided and the time for resin sealing can be shortened.

1: is a schematic diagram which shows an example of the resin sealing apparatus which concerns on embodiment of this invention.
FIG. 2 is a diagram showing a flowchart showing a part of the operation of the resin sealing device.
3 is an operation diagram (Fig. 3 (A)) showing a part of the operation of the resin sealing device and a diagram schematically showing a change in viscosity of the resin (Fig. 3 (B)).
4 is a schematic diagram showing a part of the operation diagram of FIG. 3 in more detail.
FIG. 5 is a schematic diagram showing a relation between a part of the operation diagram of FIG. 4 and the compression pressure. FIG.
FIG. 6: is a schematic diagram which shows the positional relationship of a typical upper mold | type and a lower mold | type in the operation diagram of FIG.

EMBODIMENT OF THE INVENTION Hereinafter, an example of embodiment of this invention is described in detail, referring an accompanying drawing.

First, the schematic structure of the resin sealing apparatus which concerns on embodiment of this invention is demonstrated using FIG. Here, the "substrate 102" is shown as a representative example of supporting a semiconductor chip such as a PCB substrate or a lead frame. In addition, the "semiconductor chip 104" is included in the molded article. However, in this embodiment, the molded object also includes a bonding wire for connecting the substrate 102 and the semiconductor chip 104. In addition, the "resin 106" represents a thermosetting resin, and in this embodiment, has a flat plate shape (solid) formed in advance. However, the thickness of the "resin 106" is substantially the same as the resin sealing thickness h1 described later.

As shown in FIG. 1, the resin sealing device 100 includes an upper mold 120 (first mold) and a lower mold relatively accessible and spaced apart from the upper mold 120 by a driving source (not shown). It has the metal mold | die 114 provided with the lower mold | type 130 (2nd metal mold | die). The resin sealing apparatus 100 arrange | positions the semiconductor chip 104 mounted on the board | substrate 102 with the resin 106 in the cavity of the metal mold 114, and depressurizes and heats the metal mold 114. The resin is sealed by applying a compression pressure to the semiconductor chip 104. However, the drive source which is not shown in figure is a motor (rotary drive source) mentioned later.

Hereinafter, the components will be described in detail.

As shown in FIG. 1, the mold 114 includes an upper mold 120 and a lower mold 130. The upper mold 120 includes an upper compression mold 122 and an upper frame 124. The upper compression mold 122 is mounted on and fixed to the stationary platen 110 of the mold 114. The upper compression mold 122 is provided with a decompression mechanism 116, so that the closed space generated when the mold 114 is shaped can be decompressed. In addition, an adsorption mechanism 118 is provided in the upper compression mold 122, and the substrate 102 can be adsorbed and supported on the surface of the upper compression mold 122. The upper frame 124 has an edge shape surrounding the outer circumference of the upper compression mold 122 and is attached to the upper compression mold 122 via a spring 126. For this reason, the upper frame 124 is relatively movable with respect to the upper compression mold 122. The sealing member (O-ring etc.) 124A is provided in the surface which opposes the lower mold | type 130 of the upper frame 124. As shown in FIG. However, a sealing member (not shown) is also provided on the sliding surfaces of the upper compression mold 122 and the upper frame 124.

The lower mold 130 includes a lower compression mold 132 and a lower frame 134. The lower compression mold 132 is attached to the movable platen 112 of the mold 114. For this reason, the lower mold | type 130 becomes relatively accessible and spaced apart with respect to the upper mold | type 120 in the up-down direction of FIG. The lower frame 134 has an edge shape surrounding the outer circumference of the lower compression mold 132 and is attached to the lower compression mold 132 via a spring 136. For this reason, the lower frame 134 is movable relative to the lower compression mold 132. When the upper mold 120 and the lower mold 130 approach, the lower frame 134 may support (clamp) the substrate 102 together with the upper compression mold 122. At the same time, the lower frame 134 is able to abut through the upper frame 124 and the lower frame film 108. However, the lower mold 130 is provided with a lower frame drive mechanism 138 for controlling the up and down movement of the lower frame 134 relative to the lower compression mold 132. For this reason, the lower frame drive mechanism 138 can control the position of the lower frame 134 appropriately in the resin sealing step.

Moreover, the lower mold | type 130 is provided with the film adsorption mechanism not shown, and the lower frame film 108 attached to the surface of the lower mold | type 130 can be adsorbed and supported. The lower frame film 108 is stretchable and has good peelability from the lower mold 130 and the molded article after resin sealing even when heated.

The movable platen 112 on which the lower mold 130 is mounted is connected to a motor (rotary drive source) not shown. The motor is provided with a rotary encoder (not shown) for detecting the rotation amount. As a result, the lower mold 130 is accessible and spaced apart from the upper mold 120 by a motor, and a rotary encoder mounted on the motor makes it possible to specify the position of the lower mold 130 relative to the upper mold 120. Surface location (by driving source) ”can be obtained. The "index position" based on this rotary encoder is a reference position until the lower mold 130 contacts the upper mold 120 via the substrate 102, the resin 106, and the lower frame film 108 (described later). (Until Yst) is correlated with the actual distance (or drive speed) of the lower mold 130 with respect to the upper mold 120. After the lower mold 130 contacts the upper mold 120 via the substrate 102, the resin 106, and the lower frame film 108, the lower mold 130 has a correlation with the compressive pressure (or the speed of increase in the compressive pressure). have. In addition, from this point of high reproducibility, it is optimal in the present embodiment to set the position determined by the rotary encoder attached to the motor to the "indicator position". However, the specific value of the drive speed between each indicator position shown in the following description is converted into the speed of the no load to the upper mold | type 120 of the lower mold | type 130. However, the compression pressure is detected by the mechanism which detects the pressure which is not shown in figure.

Here, reference numeral 128 denotes a movable protruding member provided on the upper die 120. As the lower frame 134 moves relative to the lower compression mold 132, the amount of expansion and contraction of the lower frame film 108 is increased by protruding the projection member 128 into the recess 134A on the lower frame 134. Minimizing. Although not shown in FIG. 1, a plurality of heaters are embedded in the upper mold 120 and the lower mold 130. By the heater, the mold 114 is heated to a predetermined temperature (for example, 175 degrees) for resin sealing.

A series of operations of the resin sealing device 100 is performed from an operation screen not shown. Based on the operation from the operation screen, an operation of the mold 114 or the like is controlled by a processing device (control means) not shown.

Next, operation | movement of the resin sealing apparatus 100 is demonstrated using FIGS. However, the vertical axis Y in the graphs of FIGS. 3 and 4 is an index position of the lower compression mold 132 (or movable platen 112) determined by a rotary encoder mounted on a motor (hereinafter, simply an index position). Or the index position of the lower mold 130). That is, it is shown that the drive which tries to bring the lower mold | type 130 closer to the upper mold | type 120 is made, so that the surface position Y is large. However, graph Gj of FIG. 3, FIG. 4 is by conventional control, and graph Gh is based on this embodiment. As shown in FIG. 6C, the sum of the thickness h of the substrate 102 and the resin sealing thickness h1 of the semiconductor chip 104 constitutes the upper compression mold of the upper mold 120 constituting the cavity ( It corresponds to the distance between the surface of 122 and the surface of the lower compression mold 132 of the lower mold 130. At this time, the index position Y of the lower mold 130 with respect to the upper mold 120 is set as the reference position Yst.

First, in the mold opening state in which the upper mold 120 and the lower mold 130 are spaced apart, the substrate 102 is sucked and fixed to the upper compression mold 122 by a conveyance mechanism (not shown). Then, a resin mounting hand (not shown) moves into the mold 114 (time t0 in FIG. 3). In addition, the lower frame film 108 is disposed on the lower mold 130 and adsorbed. At this time, by the lower frame drive mechanism 138, the positions of the upper surface of the lower frame 134 and the upper surface of the lower compression mold 132 are the same. However, the die 114 is heated to a constant temperature (for example, 175 degrees) at the time of compression sealing.

Next, the movable platen 112 is raised to set the index position Y of the lower die 130 from Y0 to Y1. And the resin 106 is mounted on the lower frame film 108 (time t1 in FIG. 3). Then, the movable platen 112 is lowered to return the index position Y of the lower mold 130 to the position Y0 (step S2 in FIG. 2 and time t2 in FIG. 3). Then, the resin mounting hand is retracted outward from the region of the mold 114 (step S4 in FIG. 2).

Next, the movable platen 112 is moved upward to bring the lower mold 130 closer to the upper mold 120. Then, at the stage where the ground position Y of the lower mold 130 becomes the position Y2 (decompression position) (step S6 in FIG. 2 and time t3 in FIG. 3), the rising of the movable platen 112 is stopped. The pressure reduction operation is started for the mold 114 (start of the decompression time). However, at this point in time, the resin 106 on the lower mold 130 and the substrate 102 adsorbed on the upper mold 120 are not in contact with each other.

Next, the movable platen 112 is moved upward to raise the ground position Y of the lower die 130 from the reduced pressure position Y2 to the driving speed V2 (for example, 44 mm / s or less) by the motor. (Time t4 in FIGS. 3 and 4). Then, the index position Y of the lower mold 130 is bonded to the resin 106 in a state where the resin 106, the bonding wire, and the substrate 102 are disposed on the upper mold 120 and the lower mold 130, respectively, and heated. The wire and the semiconductor chip 104 are in non-contacting position (first touch position) Y3 immediately before contacting (the state of the time t5 in FIG. 2, the time t5 in FIG. 3, and the FIG. . Then, the drive speed V2 is slowed down to the drive speed V3 from the first touch position Y3 (for example, about 2 mm / s). Then, the lower frame drive mechanism 138 starts the lower frame 134 to rise. However, before the first touch position Y3, the protruding member 128 protrudes and pushes the lower frame film 108 into the recess 134A as shown in FIG. 1. The upper frame 124 is in contact with the lower frame 134 via the lower frame film 108, and the lower frame film 108 is fixed. That is, by this contact state, the closed space (state of FIG. 6 (A)) by the upper mold | type 120 and the lower mold | type 130 before the first touch position Y3 is sealed, and pressure reduction is performed. . Then, the depressurization ends at the stage where the raising of the lower frame 134 ends (end of decompression time and start of compression time).

Here, the first touch position Y3 is specified by the first position referred to at the index position Y of the lower mold 130 with respect to the upper mold 120. In the present embodiment, the distance from the surface of the upper compression mold 122 to the surface of the lower compression mold 132 obtained from the index position Y by the motor at the first touch position Y3 is the distance of the substrate 102. It is preferable to set it as the sum of the value of 4 times or more of thickness h and resin sealing thickness h1. To be precise, the distance is the sum of the thickness of the substrate 106 and the thickness of the resin 106 and at least three times the thickness h and the resin sealing thickness h1, and the resin sealing thickness h1 and the resin 106. ) Is almost the same thickness. This means that the bonding wire, which is electrically connected to the substrate 102 of the semiconductor chip 104, protrudes to a lower side than the semiconductor chip 104 to a certain height, for example. In such a case, it becomes possible to ensure the non-contact state of the bonding wire and the resin 106. In addition, resin sealing thickness h1 is a value which subtracted the thickness h of the board | substrate 102 from the thickness of the molded article containing the board | substrate 102 after resin sealing, as shown to FIG. 6 (A). However, in this embodiment, the displacement amount of the lower frame 134 with respect to the lower compression mold 132 is maximum 4.5 mm. For this reason, the maximum distance from the surface of the upper compression mold 122 defined at the first touch position Y3 to the surface of the lower compression mold 132 becomes (4.5 mm + thickness h of the substrate 102). .

Next, the movable platen 112 is moved upward to move the lower mold 130 from the first touch position Y3 to the upper mold 120 at the drive speed V3. And the index position Y of the lower mold | type 130 is made into the position Y4 (low speed switching position) (step S10 in FIG. 2, the time t6 in FIG. 4, and the state of FIG. 6 (B)). At the low speed switching position Y4, the drive speed V3 is changed from the low speed drive speed V4 (for example, about 0.5 mm / s). In the low-speed switching position Y4, as shown in FIG. 6 (B), ascending of the lower frame 134 is terminated and the substrate 102 is held by the lower frame 134 and the upper compression mold 122. It becomes a state. As a result, the substrate 102 is securely fixed. The low speed switching position Y4 is specified by the fifth position referred to at the position of the lower mold 130 with respect to the upper mold 120. In the present embodiment, the distance from the surface of the upper compression mold 122 to the surface of the lower compression mold 132 obtained from the ground position Y by the motor at the low speed switching position Y4 is the distance of the substrate 102. It is preferable that the sum of the thickness h and the resin sealing thickness h1 is 1.8 times or more. To be precise, the distance is a sum of a thickness of the substrate 106 and a value of 0.8 times or more of the resin sealing thickness h1 and the thickness of the resin 106 and the resin sealing thickness h1 and the resin 106. ) Is almost the same thickness. Alternatively, the distance from the surface of the upper compression mold 122 to the surface of the lower compression mold 132 is the thickness h of the substrate 102, the resin sealing thickness h1, and the thickness h0 of the semiconductor chip 104. It may be summed. However, if necessary, the driving speed may be changed at a position between the first touch position Y3 and the low speed switching position Y4.

Next, the movable platen 112 is moved upward to move the lower mold 130 from the low speed switching position Y4 to the upper mold 120 at the drive speed V4. The index position Y of the lower mold 130 is closer to the upper mold 120 than the first touch position Y3 (first position) and the low speed switching position Y4 (fifth position), but the reference position Yst. Is a position Y5 (lowest speed switching position) which is farther from the front side and immediately before the compression pressure is started (step S12 in FIG. 2, time t7 in FIG. 3, FIG. 4). At the minimum speed switching position Y5, the drive speed V4 is changed from the minimum speed drive speed V5 (for example, about 0.05 mm / sec and 0.2 mm / sec even at the maximum). The lowest speed switching position Y5 is specified as the second position that is referred to from the position of the lower mold 130 with respect to the upper mold 120. In this embodiment, the distance from the surface of the upper compression mold 122 to the surface of the lower compression mold 132 obtained from the ground position Y by the motor at the minimum speed switching position Y5 is the substrate 102. It is preferable that the sum of the thickness h, the resin sealing thickness h1, and the value between 0.1 mm and 0.3 mm.

Next, the movable platen 112 is moved upward to move the lower mold 130 from the lowest speed switching position Y5 to the upper mold 120 at the drive speed V5. The index position Y of the lower mold 130 is set to a position Y6 (acceleration position) that is closer to the upper mold 120 than the reference position Yst and immediately after the compression pressure is started (step S14 in FIG. 2). , Time t8 in FIG. 4). At the acceleration position Y6, the drive speed V6 is changed from the drive speed V5 to the drive speed V6 (for example, 1 mm / sec or more). Acceleration position Y6 is specified by the 3rd position mentioned in the position of the lower mold | type 130 with respect to the upper mold | type 120. FIG. In this embodiment, the distance from the surface of the upper compression mold 122 to the surface of the lower compression mold 132 obtained from the index position Y by the motor at the acceleration position Y6 is the thickness of the substrate 102. It is preferable that the sum of (h) and the resin sealing thickness h1 and the value between (-0.05mm to -0.15mm) is made. However, in the acceleration position Y6 (third position), as shown in FIG. 5, the compression pressure of 1 MPa to 2 MPa generate | occur | produces. In addition, in this embodiment, time (time t1) until the lower mold 130 moves to the acceleration position Y6 (third position) after resin 106 is mounted in the lower mold 130 which comprises a cavity. Time to t8) is between 20% (Tg1) and 40% (Tg2) of the gel time (Tg) as shown in FIG. 3 (B). That is, according to this embodiment, the movement of the metal mold | die 114 can be completed in the low viscosity area | region AR of resin 106 also in the graph Gv1 based on the inventor's new discovery knowledge. 6 (C) in the process of moving the movable platen 112 upward to bring the lower mold 130 closer to the upper mold 120 at the driving speed V5 from the minimum speed switching position Y5. A condition is occurring.

Next, the movable platen 112 is moved upward to move the lower mold 130 from the acceleration position Y6 to the upper mold 120 at the driving speed V6. Then, the index position Y of the lower mold 130 is closer to the upper mold 120 than the reference position Yst, and the position Y7 is the maximum compression pressure applied to the semiconductor chip 104 (compression pressure). Position) (step S16 in FIG. 2, time t9 in FIG. 3, FIG. 4). At the holding pressure position Y7, the driving speed is zero from the driving speed V6 (the end of the compression time and the start of the cure time). The holding | maintenance position Y7 is specified by the 4th position mentioned by the index position Y of the lower mold | type 130 with respect to the upper mold | type 120. As shown in FIG. However, the maximum compression pressure is the holding pressure. The holding pressure is determined so as not to cause "sink mark" (molding abnormality due to curing shrinkage of the resin) on the molded article during curing (curing), and is set between 8 MPa and 12 MPa in this embodiment.

Next, after the cure time has elapsed, the movable platen 112 is spaced apart from the fixed platen 110. Then, the upper mold 120 and the lower mold 130 are opened, and the resin-sealed substrate 102 (simply referred to as a molded product) is taken out by a conveyer not shown.

Thus, this embodiment puts new discovery knowledge into the analysis of the viscosity change of resin 106, and changes the drive speed of the lower mold | type 130 with respect to the upper mold | type 120 at the time of resin sealing. The new discovery knowledge will be described below with reference to Fig. 3B.

In FIG. 3B, the state of the change in the viscosity Vs of the resin 106 with respect to the time t when the thermosetting resin 106 is heated for a predetermined time is schematically shown. The graph which shows the viscosity of resin 106 originally estimated by the inventor is shown by Gv. In this case, even if the driving speed of the lower mold with respect to the upper mold is slowed down as the distance from each other becomes short, the resin 106 maintains low viscosity over a wide range BR of the gel time Tg, thereby avoiding resin sealing defects. I think it is possible. However, from the inventor's new discovery knowledge, a graph showing the viscosity of the resin 106 is assumed to be Gv1. That is, even within the gel time Tg, the region of low viscosity of the resin 106 is narrow, and the lowest viscosity state of the resin 106 comes at an early timing in the first half of the gel time. The resin 106 gradually increases in viscosity from the point in time tv at which the resin 106 becomes the minimum viscosity, and the curing proceeds. For this reason, by simply slowing the driving speed, the load on the bonding wire becomes large due to the effect of the viscosity increase of the resin 106, and it is considered that resin sealing failure occurs. In particular, a slight increase in the viscosity of the resin 106 also affects thinning of the bonding wires.

For this reason, in this embodiment, as long as possible in the gel time Tg, that is, even if the driving speed is slowed down, the resin 106 has a viscosity as low as possible, while the mold 114 of the mold 114 has a low viscosity. We are trying to complete the move.

Specifically, in the present embodiment, the drive speed V5 from the minimum speed switching position Y5 (second position) to the acceleration position Y6 (third position) is transferred to the shape of the mold 114. Are the slowest. At the same time, the drive speed V3 from the first touch position Y3 (first position) to the low speed switching position Y4 (the fifth position), and the lowest speed switching position Y5 from the low speed switching position Y4 (the fifth position) The driving speed V4 to the (second position) and the driving speed V6 from the acceleration position Y6 (third position) to the holding pressure position Y7 (fourth position) are the lowest speed switching positions Y5. It is faster than the drive speed V5 from the (second position) to the acceleration position Y6 (third position).

That is, in this embodiment, the drive speed V5 is slowed most in the shape of the metal mold | die 114 only when a compression pressure is started. In particular, immediately after the start of the compression pressure, the driving speed V6 is increased as opposed to the conventional idea, so that the movement of the mold 114 in the mold is reduced while the viscosity of the resin 106 is low. It is possible to complete. For this reason, the influence of resin 106 on the bonding wire of the semiconductor chip 104 is minimized by these synergistic effects. That is, even when the resin sealing thickness h1 having a small amount of the resin 106 is thin, the resin sealing defect can be avoided. At the same time, the time for resin sealing can be shortened. In fact, even if the bonding wire diameter is 20 micrometers or 18 micrometers, and the resin thickness on a semiconductor chip is 0.3 mm in the conditions of this embodiment, a resin sealing defect can be avoided.

The drive source of the lower die 130 on which the movable platen 112 is mounted is a motor, and the index position Y by the drive source is a position determined by a rotary encoder mounted on the motor. As a result, a reproducible index position can be obtained at low cost. In more detail, the actual position of the lower mold 130 is the same or only a little change with the volume change caused by the phase change of the resin 106, and most of the rotational amount of the motor increases the compression pressure. Even when the acceleration position Y6 (third position) and the holding pressure position Y7 (fourth position) are in the state in charge of, the output of the rotary encoder, that is, the ground position has a continuity, with high accuracy and high reproducibility. , Position information and compression pressure information of the lower mold 130 can be obtained. A description with reference to FIG. 5 is as follows.

5 shows the relationship between the compression pressure and the ground position Y of the lower mold 130 with respect to the upper mold 120. The vertical axis P represents the compression pressure, and the vertical axis DY represents the distance between the ground position base of the upper die 120 and the lower die 130. As shown in FIG. 5, the compression pressure does not arise to the minimum speed switching position Y5 (second position), but rises rapidly after the acceleration position Y6 (third position). That is, after the acceleration position Y6 (third position), most of the output of the motor for the movement of the movable platen 112 is used to cause the compression pressure, so that the position detection by the rotary encoder It will be out of position. However, in the rotary encoder, since the output is continuous and high precision, the position of the lower mold 130 by the movable platen 112 can be reproduced with high precision. However, it is not necessarily limited to rotary encoders. For example, the movable platen may be moved by the toggle link, and the index position Y may be obtained based on the rotation speed of the ball screw that drives the toggle link.

Further, the driving speed V5 from the minimum speed switching position Y5 (second position) to the acceleration position Y6 (third position) is converted into an approach speed at no load from the lower mold 130 to the upper mold 120. Up to 0.2 mm / sec, and the driving speed V6 from the acceleration position Y6 (third position) to the holding pressure position Y7 (fourth position) is increased from the lower mold 130 to the upper mold 120. It is 1mm / sec or more in terms of approach speed under no load. Further, the drive speed V6 from the acceleration position Y6 (third position) to the holding pressure position Y7 (fourth position) is the acceleration position Y6 (the minimum speed switching position Y5 (second position) ( 3 times or more of the drive speed V5 to a 3rd position). For this reason, the completion time of the movement of the metal mold in the mold can be made faster than before, and the resin sealing defect can be avoided and the time for resin sealing can be shortened more than before.

In addition, since the compression pressure at the acceleration position Y6 (third position) is between 1 MPa and 2 MPa, even if there is a practical error (about ± 100 mg) in the amount of the resin 106, the minimum speed switching position (Y5). It is possible to spread the resin 106 approximately throughout the cavity during the slowest driving speed V5 from the (second position) to the acceleration position Y6 (third position). For this reason, the resin sealing defect can be most stably avoided while shortening the time of resin sealing. However, it is not necessarily limited to this.

In addition, the surface of the upper mold 120 (upper compression mold 122) and the lower mold 130 (lower) obtained from the index position Y by the motor at the first touch position Y3 (first position). The distance of the surface of the compression mold 132 is the sum of the thickness h of the board | substrate 102 and the value four times or more of the said resin sealing thickness h1, However, rigidity is not necessarily required. In addition, it is not necessarily limited to this.

In addition, the processing apparatus (control means) further determines the position between the first touch position Y3 (first position) and the lowest speed switching position Y5 (second position) at the low speed switching position Y4 (the fifth position). And the drive speed V4 from the low speed switching position Y4 (the fifth position) to the lowest speed switching position Y5 (the second position) from the acceleration position Y6 (the third position) to the pressure holding position Y7. It is slower than the drive speed V6 to (4th position). For this reason, if a part of the bonding wire, etc. in the semiconductor chip 104 are in contact with the resin 106 at the minimum speed switching position Y5 (second position), the driving speed to be reached therein becomes slow. It becomes possible. That is, the influence of the thermosetting resin 106 on the semiconductor chip 104, the bonding wire, etc. can be further reduced, and the occurrence of resin sealing failure can be further reduced. However, it is not necessarily limited to this.

In addition, the distance of the surface of the upper mold | type 120 and the surface of the lower mold | type 130 calculated | required from the surface position Y by the motor in the low speed switching position Y4 (5th position) is the thickness of the board | substrate 102 ( Although it was set as the sum of h) and the value 1.8 times or more of resin sealing thickness h1, it is not necessarily limited to this. In addition, the numerical value is not necessarily required to be exact.

Further, the time until the mold 114 is heated to a predetermined temperature (175 degrees), the resin 106 is mounted in the cavity, and the lower mold 130 moves to the acceleration position Y6 (third position) ( The time t1 to the time t8) is between 20% and 40% of the gel time of the resin 106 at the predetermined temperature, as shown in Fig. 3B. For this reason, the compression pressure can be started by making the resin 106 soften and melt | dissolve from a solid state, making sure the viscosity of resin 106 was made low. At the same time, it is possible to reliably shorten the movement completion of the mold 114 in the mold body compared with the prior art, thereby making it possible to avoid further resin sealing defects and to shorten the time for resin sealing.

In this embodiment, while the compression time which actually took 20 seconds by the conventional control was shortened to 10 seconds or less, it was possible to improve about 1 to 2% that the amount of deformation of the bonding wire was 3% or more.

That is, according to the present embodiment, even when the resin sealing thickness h1 having a small amount of the resin 106 is thin, the resin sealing defect can be avoided and the time for resin sealing can be shortened.

Although this embodiment was mentioned and demonstrated about this invention, this invention is not limited to this embodiment. That is, it goes without saying that the improvement and the design change in the range which do not deviate from the summary of this invention are possible.

For example, although bonding wire existed in this embodiment, this invention is not limited to this, The case of flip chip bonding of the semiconductor chip without a bonding wire, etc. may be sufficient. Moreover, the case where resin sealing thickness is comparatively thick may be sufficient. In any case, the present invention can correspondingly avoid a resin sealing defect and also shorten the time for resin sealing.

In addition, in this embodiment, although the resin 106 was made into the flat form shape previously, this invention is not limited to this. For example, powdery or granular resin may be sufficient.

The resin sealing device of the present invention has a remarkable effect, especially in the case where the semiconductor chip has a bonding wire and the like, and the resin sealing thickness with a small amount of resin is thin, but not limited thereto, and the usability can be further expanded. have.

100... Resin Sealing Device
102... Board
104... Semiconductor chip
106 ... Suzy
108 ... Bottom frame film
110 ... Fixed platen
112 ... Operation platen
114... mold
116... Decompression mechanism
118... Adsorption mechanism
120 ... Upper section
122... Upper compression mold
124... Upper frame
126, 136. spring
128... Protruding member
130 ... Lower type
132... Bottom compression mold
134... Lower frame
138... Lower frame drive mechanism

Claims

And a mold having a first mold and a second mold relatively spaced apart from the first mold by a driving source.
In a resin sealing device for placing a molded article mounted on a substrate with a thermosetting resin in the cavity of the mold, heating the mold under reduced pressure and applying a compression pressure to the molded article to seal the resin.
The second mold with respect to the first mold corresponding to a distance between the surface of the first mold and the surface of the second mold constituting the cavity, respectively, wherein the sum of the thickness of the substrate and the resin sealing thickness of the molded article is the same; Let the reference position by the drive source of the reference position,
The index position of the second mold with respect to the first mold with respect to the first mold that is in contact with the resin and the molded article is in contact with each other while the resin and the molded article are respectively disposed in the first mold and the second mold and heated. Position,
The index position of the second mold relative to the first mold, which is closer than the first position with respect to the first mold but far from the reference position and immediately before the compression pressure is started, is set as the second position,
The index position of the second mold relative to the first mold, which is closer to the reference position relative to the first mold and immediately after the compression pressure is started, is the third position,
The index position of the second mold relative to the first mold, which is closer to the reference position relative to the first mold and the compression pressure is the maximum compression pressure applied to the molded article, is the fourth position.
The drive speed by the drive source of the second mold with respect to the first mold from the second position to the third position is slowest in the shape of the mold, and from the first position. And a control means for making the drive speed to the second position and the drive speed from the third position to the fourth position faster than the drive speed from the second position to the third position.
Resin sealing device, characterized in that.

The method according to claim 1,
The drive source is a rotational drive source, and the index position by the drive source is a position determined by a rotary encoder mounted to the rotational drive source.
Resin sealing device, characterized in that.

The method according to claim 1 or 2,
The drive speed from the third position to the fourth position is at least three times the drive speed from the second position to the third position.
Resin sealing device, characterized in that.

The method according to claim 1 or 2,
The driving speed from the second position to the third position is at most 0.2 mm / sec in terms of the approach speed of the second mold at no load to the first mold,
The driving speed from the third position to the fourth position is 1 mm / sec or more in terms of the approaching speed at no load.
Resin sealing device, characterized in that.

The method according to claim 1 or 2,
The compression pressure in the third position is between 1 MPa and 2 MPa
Resin sealing device, characterized in that.

The method according to claim 1 or 2,
The distance of the surface of the said 1st metal mold | die and the surface of the said 2nd metal mold | die calculated | required from the index position by the said drive source in a said 1st position becomes the sum of the value of 4 times or more of the thickness of the said board | substrate and the said resin sealing thickness. there is
Resin sealing device, characterized in that.

The method according to claim 1 or 2,
The control means sets the index position between the first position and the second position as a fifth position,
Slowing the driving speed from the fifth position to the second position than the driving speed from the third position to the fourth position
Resin sealing device, characterized in that.

The method according to claim 7,
The distance of the surface of the said 1st metal mold | die and the surface of the said 2nd metal mold | die calculated | required from the index position by the said drive source in a said 5th position becomes a sum of the value of 1.8 times or more of the thickness of the said board | substrate and the said resin sealing thickness. there is
Resin sealing device, characterized in that.

The method according to claim 1 or 2,
The mold is heated to a predetermined temperature,
The time from the mounting of the resin to the cavity until the second mold moves to the third position is between 20% and 40% of the gel time of the resin at the temperature.
Resin sealing device, characterized in that.

Using a mold having a first mold and a second mold relatively spaced apart from the first mold by a driving source;
A resin sealing method in which a molded article mounted on a substrate is placed in a cavity of the mold together with a thermosetting resin, subjected to reduced pressure heating of the mold, and sealing the resin by applying a compression pressure to the molded article.
The second mold with respect to the first mold corresponding to a distance between the surface of the first mold and the surface of the second mold constituting the cavity, respectively, wherein the sum of the thickness of the substrate and the resin sealing thickness of the molded article is the same; Let the reference position by the drive source of the reference position,
The index position of the second mold with respect to the first mold with respect to the first mold that is in contact with the resin and the molded article is in contact with each other while the resin and the molded article are respectively disposed in the first mold and the second mold and heated. Position,
The index position of the second mold relative to the first mold, which is closer than the first position with respect to the first mold but far from the reference position and immediately before the compression pressure is started, is set as the second position,
The index position of the second mold relative to the first mold, which is closer to the reference position relative to the first mold and immediately after the compression pressure is started, is the third position,
The index position of the second mold relative to the first mold, which is closer to the reference position relative to the first mold and the compression pressure becomes the maximum compression pressure applied to the molded article, is the fourth position.
A step of performing the driving speed of the second mold relative to the first mold from the second position to the third position by the driving source at the slowest shape in the mold;
Performing the drive speed from the first position to the second position and the drive speed from the third position to the fourth position faster than the drive speed from the second position to the third position.
Resin sealing method comprising a.