TW447093B - Encapsulating method and encapsulating mold for semiconductor apparatus - Google Patents

Abstract

A kind of encapsulating method for semiconductor apparatus includes the following steps: (a) providing a molding die that includes a molding portion having a cavity used to accept the semiconductor apparatus, a dummy cavity connected with the cavity, and an air vent connected with the dummy cavity; (b) tightly clipping this molding die so as to make semiconductor apparatus locate in the cavity; (c) injecting the encapsulating material into the cavity and the dummy cavity; (d) curing the encapsulating material; and (e) opening the molding die to take out the molded product. The encapsulating method of this invention is characterized in that the injection head will continuously move the compressed encapsulating material and make the encapsulating material continuously flow into the dummy cavity when the cavity loaded with semiconductor apparatus is filled with the encapsulating material. On the other hand, the present invention provides a kind of molding die used for encapsulating a semiconductor apparatus, in which the molding die mainly contains a pot, a molding portion and a runner. The molding portion has a cavity used to accept the semiconductor apparatus, a dummy cavity connected with the cavity, and an air vent connected with the dummy cavity. One terminal of the runner is connected with the pot, and the other terminal is connected with the cavity via a gate. The channel connected with the cavity and the dummy cavity has approximately the same size as the gate such that, when performing the encapsulating process, this encapsulating material will first fill up the cavity through the runner and the gate, and then fill up the dummy cavity via the channel.

Description

447 0 93 V. Description of the Invention (l) Field of the Invention: The present invention relates to a method for manufacturing a semiconductor device, and more particularly to a method for sealing a semiconductor device. The invention also relates to a mold for sealing a semiconductor device. Previous technology: With the increasing demand for lighter and more complex electronic devices, the speed and complexity of the chip are relatively higher and higher, therefore higher packaging efficiency is required. Miniaturization is

The main driving force for using advanced packaging technologies, such as chip scale packages and flip chips. Compared to ball grid array packages or thin small outline packages (TSOP), both chip-scale packaging and flip-chip packaging technologies significantly increase packaging efficiency, thereby reducing the required substrate space β General In terms of a wafer-scale package, it is approximately 20% larger than the wafer itself. However, flip chip is described as the ultimate packaging technology because it is approximately as large as the wafer itself. The wafer itself is directly bonded to the substrate by solder bumps fixed on the wafer. The first figure reveals a conventional flip-chip package structure, which includes a wafer]. It is mounted on a substrate 2 using flip-chip technology. ^ Since the thermal expansion coefficient of the wafer 10 and the substrate 20 is quite different (the thermal expansion coefficient of a semiconductor wafer)

^ coefficient of thermal expansion (CTE) is about 3-5ppm ° C-1, and the coefficient of thermal expansion (CTE) of the substrate is about 20_30ppm VII-i), so the crystal > 110 and the substrate 20 preferably have a filler ( undei * fill) 30 is used to seal the gap between the tin-lead connections 12 and 12. The filler 3 0 can lighten tin-lead

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4 47 Ο 9.3 V. Description of the invention (2) Stress caused by inconsistent thermal expansion coefficient on the catch 12. The filling 30 — generally uses an automated dispensing system (a u t m a t e d underfill dispense sy stem) to place the filling material on the edge of the wafer 10. However, 'because the filling material is sucked under the wafer 10 by capillary action', it takes a considerable time to penetrate the filling material from the side of the wafer 10 into the space between the wafer 10 and the substrate 20. Therefore, the semiconductor industry has developed a conventional transfer molding method to form a gel to seal the gap between the wafer and the substrate. Please refer to the second figure, which is a cross-sectional view of a conventional mold for transfer molding method, a wafer is mounted on a substrate using flip-chip technology. As shown in the figure, (The mold is provided with a pot 40 for placing the sealing material. The pot 40 is connected to a cavity 46 through a runner 42 and a gate 44. After the sealing material is placed in the tank 40 and the mold is tightly clamped, an injection head 48 begins to move upward to compress the sealing material to fill the cavity 46 through the runner 42 and the runner 44. The gap between the wafer 10 and the substrate 20 is sealed. However, since the gap between the wafer 10 and the substrate 20 is very small (usually 0.05 to 1 mm), the air is easily covered by the wafer 10 and the substrate 20 Voids 32 will be generated from time to time. These voids 32 will cause the reliability of the mechanical and electrical connection (ie, the tin-lead connection 12) between the wafer 10 and the substrate 20 to decrease. Therefore, the 'US Patent No. No. 5998243 discloses a method for manufacturing a semiconductor device, which reduces the probability of generating voids between a wafer and a substrate by maintaining a cavity at a high vacuum (less than 10 torr). Please refer to the third circle according to the United States Patent No. 5 9 9 8 2 4 3, a mold system of a preferred embodiment

447093 V. Description of the invention (3) The brake uses a vacuum pump (shown in the figure) to reduce the pressure in the cavity 46 by venting 50. A furnace channel (exhaust 50 and channel 54 of the mold cavity 46, whose σ is connected to the diameter of the exhaust hole particles, thereby preventing the sealing material. 7 filling conductors in the filling device 劁 诰 * ^ Γ material into the exhaust hole 5 0. However, the shortcomings of the method for manufacturing the cattle conductor decoration are vacuum help and increased mold cost. Maintenance and repair, and summary of the invention: The main purpose of the present invention is to provide a method for semiconductor devices, which can be determined according to the foregoing. The technology has a problem of voids, and forms a gel to seal the gap between the wafer and the substrate. Another object of the present invention is to provide a mold for sealing a mold, which can be used to quickly form a mold. The sealing compound seals the voids and prevents the occurrence of pores. The method for sealing a semiconductor device according to the present invention between the moon and the substrate includes the steps of: (a) providing a molding die including a molding section ( (molding portion) has a mold cavity to accommodate the semiconductor device, a dummy cavity is connected to the mold cavity, and an air vent is connected to the dummy cavity; (b) a close clamp Tight the 1 make half The conductor device is located in the mold cavity; (c) the sealant material is noted = ;; and in the dummy mold cavity; (d) the sealant material is hardened; and (e) talk to remove the mold product according to the present invention In the sealing method, when the cavity containing the semiconductor device is filled with the sealing material, the injection molding moves upward and compresses the sealing material to continue to flow into the dummy cavity. Therefore, it is originally covered in The air between the wafer and the substrate will be pushed along the die flow and pushed

Face 447093 V. Description of the invention (4) Squeeze into the dummy cavity, so there will be no pores in the cavity. The invention also provides a mold for sealing a semiconductor device, which mainly comprises a can, a molding part and a runner. The tank is used to contain the sealing material = ,. The die cavity has a die cavity for accommodating the semiconductor device, a cavity is connected to the die cavity 'and a vent hole is connected to the dummy die cavity. ^ Erdaoyou-the end is connected to the tank, and the other end is connected to the pot through a bath opening. The channel connecting the mold cavity and the false mold cavity has the same size as the wash channel opening. The glue material will go through this first. And the detour is filled with mold cavities, and then filled with dummy molds through the passage. Graphical illustrations: Obviously in order to let the text invent the above two and its ^ Detailed description such as ^ the preferred embodiment of this month, and cooperate with the attached As shown in the figure, it is a cross-sectional view of a conventional flip-chip packaging structure. The two mold cavities are respectively cross-sectional views of a conventional mold. The mold contains the third chip and the previous chip is mounted on a substrate using flip-chip technology. According to the model and the whitening country winter special 5-9 9 8 24 3 1-the preferred embodiment of the mold is installed in a ^ Ϊ two mold cavities are respectively equipped with a chip using the flip chip technology / with 4 bags \ two t this The first __ preferred embodiment of the s mold is a cross-sectional view of the substrate; and, the last wafer is mounted using flip-chip technology on-Figure 5 · A cross-sectional view of the mold according to the second preferred embodiment of the present invention,

447093 V. Description of the invention (5) The kit includes a mold cavity and a wafer mounted on the board using flip chip technology. Description of drawing number: 10 wafers 12 tin-lead connection 20 substrate 30 filling 3 2 pores 4 0 cans 42 runner 44 runner gate 46 mold cavity 47 mold cavity 48 injection head 5 0 exhaust hole 54 channel 60 dummy cavity 62 Description of the invention: The fourth figure shows a mold according to the first preferred embodiment of the present invention. As shown in the figure, the mold is provided with a pot (Pot) 40 for the sealing material to be placed. The tank 40 is connected to a cavity 46 through a runner 42 and a gate 44. According to the mold of the first preferred embodiment of the present invention, # a dummy mold cavity 60 is connected to the mold cavity 46, and a vent hole "connects the two dummy mold cavity 60." Please check and refer to the fourth picture " A wafer 10 is mounted in a base-based system using a flip-chip technology. The shape of the cavity 46 is approximately the same as the sealant shape: the sealant material is placed in the can 40 3 sealant material. The mold and the two injection heads began to move upwards to compress the seal heads 48 to compress the seals upwards. The rubber material was first preheated so that when the injection gate 42 and the runner material were pressed, the sealant material would Liquify and fill the cavity 4 6 via the 4 to cover the semiconductor wafer i 〇

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V. Description of the invention (6) and sealing #a 片 1 〇 The gap of the grave board 20 Pa 〇 When the mold cavity 4 6 is filled with the sealant 'The injection head 4 8 will continue to move upward to compress the sealant material "It continues to flow into the dummy cavity 60." Therefore, the air originally enclosed between the wafer 10 and the substrate 2'0 will be pushed along the mold flow and pushed into the dummy mold 60, thereby avoiding Industrial gas. Remains in the cavity 46 and generates pores. Preferably, each dummy cavity system is interconnected to increase the mold flow pressure of the sealing material in the cavity 46 and the dummy cavity 60. After the sealant material fills the cavity 46 and the dummy cavity 60, the injection head 48 remains stationary for a predetermined time until the sealant material hardens. Then the 'injection head 48' is lowered and the mold is opened, and the molded product is taken out.

The Fengsheng plastic not only fills the mold cavity 46, but also fills the runner gate 44, Yaodao 42, and the tank 40. Therefore, when the sealant plastic is cured, does it not only envelop the wafer, but also extend along the surface of the substrate sheet 20 (that is, via the runner: 4 at 罐 to the tank 40). The cured excess sealant-the system is called a runner and must be removed before the molded product is cut. Because of the 土 面积 ΐ Ϊ 道口 "The cross-sectional area is generally smaller than the Ling • Road 42 used to help # 封 视 脱 ^" The first process is to remove the excess sealing plastic. In addition, Π: Π ί fills the dummy cavity 60. Therefore, when the mold 4 of the molded product is removed, the structure formed by removing the dummy cavity 60 can be taken together. < Mo products are cut into individual units to complete the flip-chip package W. Please refer to the fourth figure 'for connecting the cavity 46 and the dummy cavity 60. Dagger: 44: approximately the same size. In particular, this does not prevent the seal from being larger than the diameter of the filler particles in the sealant material, thereby preventing the sealant material from entering the dummy cavity M. But the size of this Tongzhou is not

447093 V. Description of the invention ⑺. Too large to prevent the removal of the forming block formed by the dummy cavity 60. The size of @ 道 64 is preferably between 0 ’丨 5_0. 25 mm. In addition, the 'k channel 62 must be smaller than the filler hole in the sealant material and the sealant material overflows the mold. Prevent this-The fifth figure discloses a mold according to a second preferred embodiment of the present invention. -Ϊ 道 ί Ξ; Tilt ί glue material placement. The can 40 is mounted on a substrate 2 via a flip-chip technology. 4 :: = = A preferred embodiment is characterized in that the minimum distance d from the gate to the side wall of the cavity is not small, and the direction is not small (as indicated by the arrow in the fifth figure). ) Two Γ Yu Gai said: The piece is thousands of lines in the mold flow side and the magnetic field j π 士 = no) half of the side length C. After the sealing material 罾 is compressed into the bell gland 枓 and f the mold is tightly closed, the injection head 48 starts to move downward: i = 时 When the semiconductor wafer 10 is covered with the sealing crystal 10 and the sealing material is covered, the injection The first 48 will follow the ff + f body sa sheet 10 is sealed to continue to flow into its and the cavity 4 7 gate, and the sealant material is compressed downwards, the additional space 70 between the 5 and 7 T coupons, so Use the push to push in: the J that is retained outside = will be passed along the die flow to increase the sealant material;; 2 = after the material fills the die cavity 47, the injection mold & pressure equalization . When sealing until the sealing material is hard &. Ran the moxibustion head 48 for a predetermined time to remove the molded product. Raise the mold i i f head 48 and open the mold, cut into individual units, that is, after removing the money gate, and cut

447093 V. Description of the invention (8) As mentioned above, according to the method for sealing a flip-chip bonded semiconductor device according to the present invention, it can avoid bubble voids between the wafer and the substrate, and quickly form a gel to seal the wafer and the substrate. The gap between. In addition, the present invention also provides a mold for encapsulating a flip-chip bonded semiconductor device, which can be used to quickly form a gel to seal the gap between the wafer and the substrate, and prevent the occurrence of bubble voids. Although the preferred embodiment of the present invention is described with a flip-chip bonding semiconductor device, other semiconductor devices using transfer molding encapsulation include, but are not limited to, a ball grid array (BG A) semiconductor package. The thin small outline package (TS0P) and chip array (Chip Array) package can also use the mold and method of the present invention to achieve the purpose and effect of the invention. Although the present invention has been disclosed by the aforementioned preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the scope of the attached patent application. 〇 stable

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Claims (1)

447093 6. Scope of patent application, a method for encapsulating a vehicle conductor device γ, comprising the following steps: providing a molding die, which includes a molding portion / (molding portion), which has a cavity to accommodate the half A guide device, a dummy cav.ity is connected to the cavity, and an air vent is connected to the dummy cavity; the mold is tightly clamped so that the semiconductor device is located in the mold. In the cavity; injecting the sealing material into the cavity and the dummy cavity; hardening the sealing material; and opening the mold to take out the molded product. Formation of dummy cavity 2. The method for sealing the semiconductor device according to item 1 of the patent application scope includes a step for removing the casting runner, wherein the molding block is also removed at the same time. S1 has set up the seal of French cubes to install the crystals and cover them with a half piece of crystals. The first half of the first half is a fan-shaped package. Please install the application body for guidance. The semi-conductor base 4 and the semi-conductor according to item 1 of the patent application scope include: a pot (pot) for holding a sealing compound (m0ldi compound); a gate (gate); and A runner, where the end is connected to the tank, and the other device is a method of sealing, wherein the ng end passes through the pouring 447093 VI. Scope of patent application The gate is connected to this cavity. The method for sealing a semiconductor device according to item 4 of the patent application, wherein the mold further comprises a channel connecting the cavity and the dummy cavity, wherein the channel and the runner gate have approximately the same size. 6. The method for sealing a semiconductor device according to item 5 of the scope of patent application, wherein the size of the channel is between 0.15-0, 25 mm. 7 / —A mold for sealing a semiconductor device, comprising: a pot for containing the sealing material; a molding part having a cavity for receiving the semiconductor device, and a dummy cavity connected to the A cavity, and a vent hole connected to the dummy cavity; a sprue mouth; and a sprue, one end of which is connected to the tank, and the other end connected to the cavity through the sprue mouth, which t, when sealing, the The sealing material will fill the cavity and the dummy cavity through the runner and the gate of the runner. The opening of the mold path should be used to guide the body, and the half-hole and one-mold rubber seals should be applied to the points. The model inch item of this rule 7 is the same as the encirclement of the road. It is profitable. It is a college diploma. You must ask Bao Shen to apply it separately. Item 8: We are invited to apply for V. .—1 —: —i -.- 'a · / · / — t Page 14 4 47 0 9 3 VI. Scope of patent application With the size of the channel in the range of 0. 15-0, 25 亳 来. 10. The mold for sealing a semiconductor device according to item 7 of the scope of the patent application, wherein each of the dummy mold cavities is in communication with each other. The sealing method includes a plurality of semiconductor devices and a bypass, and one end: 1 1, a semiconductor device sealing method, wherein the semiconductor device includes a semiconductor wafer provided on a substrate and electrically connected to the substrate. The substrate includes the following steps: a feeding die cavity, which is densely spaced at a small distance; a hard die, which includes a pot 1 for containing a mold forming part, and has a cavity for containing the plural number A vent hole is connected to the cavity; a sprue mouth; and connected to the tank, the other end is connected to the semiconductor wafer farthest from the bath mouth and the side wall of the cavity through the sprue mouth and the least side wall of the cavity is not less than the wafer One-half of the side length parallel to the direction of the mold flow; clamping the mold together so that the semiconductor device is located in the cavity of the mold cavity sealing material injected into the cavity; turning the sealing material; and opening the mold to take out the molded product. Page 15 1 2. The method for sealing a semiconductor device according to item 11 of the scope of patent application, wherein each of the molds is connected to each other.