TW518732B - A semiconductor packaging process for ball grid array (BGA) - Google Patents

Abstract

A semiconductor packaging process for ball grid array comprises: providing a substrate, dispensing adhesive, attaching dices on the substrate, wire bonding, molding, and balls implanting. The adhesive is dispensing on the adhesive areas of the substrate by a dispenser for attaching active surfaces of the dices. The quantity of the adhesive is controlled well, so that is improving the yield of the semiconductor packaging without increasing the extra cost. For semiconductor packaging industry, the adhesive is produce and use widely, so this semiconductor packaging process is increasing the yield of packing and reducing the cost.

Description

518732

[Field of the Invention] The present invention relates to a ball grid array semiconductor packaging process. The invention relates to a semiconductor packaging process of a spot-applied or applied adhesive-bonded wafer and a window-type ball grazing array substrate. ". [Prior art] In" Paper Size Packaging Method "of US Patent No. 6, 1 90, 943," a window ball grid array semiconductor package structure (window) "is disclosed.

Ball Grid Array semiconductor package) and its packaging method 'As shown in FIG. 1, the semiconductor package structure 20 mainly includes a substrate 22 (ie, a ball grid array substrate with a window type), a wafer 24, and a colloid 42 A thermoplastic adhesive 28, a plurality of metal wires 32, and a plurality of solder balls 44 ', wherein the substrate 22 has an elongated window 34 penetrating the upper surface 30 and the lower surface 38, and the active surface 26 of the wafer 24 (active surface) is adhered to the upper surface 30 of the substrate 22 with a thermoplastic adhesive 28, the metal wire 32 is electrically connected to the wafer 24 and the substrate 22 through the window 34, and the sealant 4 2 is formed on the wafer 24 and the window The periphery of 3 to protect the chip 24 and the metal wire 32, and a plurality of balls 44 'arranged in a matrix are formed on the lower surface 38 of the substrate 22, so that the semiconductor package structure 20 becomes a "window ball grid array" ( That is, the semiconductor package structure of Window BGA. The packaging method of the above-mentioned semiconductor package structure 20 is as follows: 1. A substrate 22 is provided. The substrate 22 has an upper surface 30, a lower surface 38, and a window 3 4 penetrating the upper surface 30 and the lower surface 38. 2. 1. Apply a liquid thermoplastic adhesive 28 (stenci 1 ing) to the upper surface 30 of the substrate 22;

518732 V. Description of the invention (2) The active surface 26 of the wafer 24 contacts the thermoplastic adhesive 28 on the substrate 22, so that the pads 36 of the active surface 26 of the wafer 24 correspond to the window 3 4; At a predetermined temperature (190 ° C), pressure (390g), and time (five seconds), the substrate 22 and the wafer 24 are heated under pressure to bond the two together; five, wire bonding ) Method to pass the metal wire 32 through the window 34 to electrically connect the solder pad 36 of the wafer 24 and the conductive pad 41 of the substrate 22; 6. form a gel 42 on the periphery of the wafer 24 and the window 34; The lower surface 3 8 of the substrate 22 is implanted with a plurality of solder balls 4 4 arranged in a matrix. Through the above steps, a semiconductor package structure 20 (that is, a window ball grid array package structure) is prepared. Since the thermoplastic adhesive 28 is applied by screen printing (step 2), it is formed on a part of the upper surface of the substrate 22 30. When the wafer 24 and the substrate 22 are heated and pressed, the flow of the liquid thermoplastic adhesive 28 is not easy to control. When the amount of the applied glue is too much, the liquid thermoplastic adhesive 28 will overflow and cover the wafer 24. The solder pad 36 leads to the failure of wire bonding. Therefore, the amount of printing and application of the thermoplastic adhesive 28 must be accurately controlled, so that its manufacturing yield is still low, and the reliability of semiconductor packaging is severely reduced. In the semiconductor packaging industry, The thermoplastic adhesive 28 (such as a solvent-free, flexible, semi-bright silicone rubber, etc.) is not mass-produced and used, so its cost is relatively high. In addition, the conventional method of wafer bonding during the sealing process is: Pressing and heating are performed at the same time (step 4). However, the machine to be pressurized and heated at the same time is more complicated and costly, and it also increases the cost of the packaging process. [Objective and Summary of the Invention] The main object of the present invention is to provide a ball grid array semiconductor packaging process, which is to apply or apply adhesive on the die-bonding area of the substrate, and then apply 518732 first.

The wafer is pressurized to adhere to the substrate, and the adhesive is cured by heating, so that the wafer is tightly adhered to the substrate. Even when the subsequent high-temperature curing forms a seal, the wafer and the substrate are tightly combined. In addition, When applying or applying adhesive, the amount of glue is easy to control, and the yield of the semiconductor package can be improved without additional material cost. A secondary object of the present invention is to provide a ball-shaped array semiconductor package j, which is used in the semiconductor packaging industry. The above-mentioned adhesive is an epoxy adhesive or silver adhesive (Ag — epoxy adhesive) · ·· Such thermosetting or thermoplastic adhesives are mass-produced and used in the semiconductor packaging industry, so their cost is low, and the ball grid array semiconductor packaging process is pressurized and then heated without using costs. The more expensive machine can be pressurized and heated at the same time, so the process cost is reduced. The aforementioned semiconductor packaging process is to apply or apply the above-mentioned adhesive to the die attach area of the substrate, and then paste the active surface of the wafer to the die attach area of the substrate, and then perform heating to make the The adhesive is cured, so that the wafer is tightly adhered to the substrate, and then wire bonding and sealing are performed. When the sealing is performed in a molding, molding, or potting method, the adhesive is cured at a high temperature. The formation of a good sealant can also tightly combine the wafer and the substrate. Therefore, the semiconductor packaging process can improve the reliability of the semiconductor packaging and reduce the manufacturing cost. [Detailed description of the invention] Please refer to the attached drawings. The present invention will enumerate the following embodiments: In a specific embodiment of the present invention, Figures 2a to 2e are a ball grid array, (Hereinafter referred to as BGA) semiconductor package

Page 7 518732 V. Description of the invention (4) A schematic cross-sectional view of the implementation steps of the process. Figure 3 is a top view after the adhesive is applied by means of adhesive coating. 'Figure 4 is a cross-sectional view of a B G A package structure. As shown in FIG. 4, the BGA package structure 100 mainly includes a chip 110, a gel 120, an adhesive 130, a substrate 140, a plurality of metal wires 150, and a plurality of solder balls 160, wherein the substrate The 14o series has a window 146 penetrating the upper surface 144 and the lower surface 145 thereof. The active surface 111 of the wafer 11 is adhered to the upper surface 144 of the substrate 14 and the metal wire 150 is wired. (Wire bonding) The chip 110 and the substrate 140 are electrically connected through the window 146. The sealing body 120 is used to seal the chip 110 and the metal wire 150 to protect the chip 110 and the metal wire 150 from the external environment. In addition, a plurality of solder balls 1 60 arranged in a matrix are formed on the lower surface 145 of the substrate 14. The material of the solder balls 160 is a ship tin alloy, etc., which makes it a ball grid array (ie) packaging structure. The packaging process of the above BGA packaging structure 100 is detailed as follows: First, as shown in FIG. 2a, a substrate 140 is first provided. The substrate 140 has an upper surface 144 and a lower surface 145, and the upper surface 1 of the substrate 140 is provided. The 4 4 series has at least one sticky crystal region 1 4 8, the sticky crystal region 1 4 8 has at least one window 146 penetrating the upper surface 144 and the lower surface 145 of the substrate 140, and the lower surface 145 of the substrate 140 forms a The circuit layer 143 has a metal circuit (not shown in the figure) and a plurality of contact pads 142 (contact pads) located around the window 146. The metal circuit (not shown in the figure) is used for conducting connections. The solder ball 1 6 0, and the lead 塾 1 4 2 are used to solder the metal wire 1 5 0 〇

518732 V. Description of the invention (5) As shown in Fig. 2b, the glue sticking area 1 4 4 on the upper surface 1 4 4 of the substrate 1 4 0 is dispensed by the dispenser 170 (dispenser). 30, or as shown in FIG. 3, 'It is a method of applying an adhesive 1 3 0 to the crystallized region 1 4 8 of the substrate 1 4 0 by an adhesive method' wherein the adhesive 1 3 0 is an epoxy adhesive ( epoxy adhesive) or Ag (epoxy adhesive) ... and other thermosetting or thermoplastic adhesives. After that, as shown in FIG. 2c, the active surfaces 1 ij of the plurality of wafers 1 1 0 are brought into contact with the adhesive 1 30 on the die attach region 148 of the substrate 140, and a predetermined pressure is applied to make the wafers 1 10 adhere to the substrate 1 4 0, and the welding pad 11 2 of the wafer 11 〇 is located at the middle position of the active surface 111 of the wafer 11 0 and the position corresponds to the window 1 4 6 and then heated at a predetermined temperature (about 1 50 to 7 5 or so). ), The adhesive 130 is cured, so that the plurality of wafers 10 are tightly adhered to the substrate 140. Then, as shown in FIG. 2D, the plurality of wafers 丨 丨 pads 丨 2 are wired with metal wires 150 through the window 146 of the substrate 140 to be electrically connected to the conductive pads 143 of the circuit layer 143 of the substrate 140 142, and then forming a sealing compound 120 by molding, printing, or potting, etc., to seal a plurality of wafers 1 () and metal wires 150, and then by high temperature (about 150 to 1800c) is cured to form a sealant 120 with good adhesion, and tightly bond the wafer π0 and the substrate 14o. Finally, as shown in FIG. 2e, a plurality of ball 丨 6 〇 is planted on the circuit layer 1 4 3 of the lower surface 145 of the substrate 14, and the solder balls 6 〇 are arranged in a matrix, so that the substrate 140 is Form a plurality of BGA packaging structures 100 (which are also window ball grid array packaging structures), and then cut the substrate 4 to make a plurality of M a

518732 V Description of the invention (6) The packaging structure 100 becomes a single packaging unit (as shown in Figure 4). During the above-mentioned packaging process of the BGA package structure 100, the adhesive 30 was applied to the substrate 14 14 with the adhesive region η 8 $ on the upper surface 1 4 4 of the substrate 1 170 by a dispenser, or by gluing. The method is applied to the die-bonding region 148 of the substrate 14). Its glue amount is easy to control and its cost is low. It can reach the yield of semiconductor packaging without additional material cost and cure the glue by heating. Before 30, the wafer 110 is first pressed to adhere to the substrate 40, and then heating is performed, and the curing temperature of the adhesive 1.30 is 150. 〇 to 175. 〇 or so, when warming up 15 〇. 〇 to 175 C or so 'the adhesive 130 will chimney and the wafer 110 is tightly adhered to the substrate 1 4 0', and then wire bonding and sealing are performed, and the sealing is performed by stamping, printing or ... The thermosetting epoxy resin is poured in other ways. When the thermosetting epoxy resin is poured and cured, the temperature is about 150 to 180 °, and it is cured at high temperature to form a good sealant 12 °, which can also be tightly bonded. The wafer 110 and the π-based substrate 140 are also used in the semiconductor packaging industry. The adhesive 130 (that is,% oxygen adhesive or silver adhesive, etc.) is mass-produced and used. Adhesive 130 can be used in large quantities at low cost, and the encapsulation process of = BGA package structure 1000 is performed after pressing and heating. ^ Need to use a conventional die attaching machine and baking equipment without purchasing separately And the use of expensive machines that can be heated under pressure at the same time, so the low cost and large use of adhesive 130 and the versatility of the process equipment have reduced process costs. Therefore, the scope of protection of the present invention is subject to the scope of the appended patent application. Any changes and modifications made by those skilled in the art without departing from the spirit and scope of the present invention are protected by the present invention. range. Page 518 732 Brief description of the drawings [Illustration of the drawings] Figure 1: Sectional view of the '-S 0 c package structure in US Patent No. 6, 19〇, 943 "Chip Size Packaging Method"; Figure 2 a · According to a specific embodiment of the present invention, a cross-sectional view after a substrate is provided; FIG. 2b. According to a specific embodiment of the present invention, a cross-sectional view after the adhesive is applied by a dispensing method; FIG. 2c is according to the present invention. A specific embodiment, a cross-sectional view after the wafer is pasted; FIG. 2d. According to a specific embodiment of the present invention, a cross-sectional view after wire bonding and sealing; FIG. 2e. According to a specific embodiment of the present invention, a plant connection Cross-section view after solder ball; Figure 3: Top view in accordance with one embodiment of the present invention, or after application of adhesive by means of glue coating; and Figure 4: In a specific embodiment of the present invention, A cross-sectional view of a BGA package structure. [Illustration of drawing number] 20 semiconductor package structure 22 substrate 24 chip 26 active surface 28 thermoplastic adhesive 30 upper surface 32 metal wire 34 40 window conductive layer 36 solder pad 38 lower surface 41 lead pad 42 sealing body 44 solder ball

518732 Brief description of the diagram 100 BGA package structure 110 Chip 111 Active surface 112 Solder pad 120 Sealant 130 Adhesive 140 Substrate 142 Leading pad 143 Circuit layer 144 Upper surface 145 Lower surface 146 Window 148 Sticky region 150 Metal wire 160 Solder ball 170 Dispenser

Page 12

Claims (1)

518732 a. Scope of patent application [Scope of patent application] 1. A semiconductor packaging process comprising the steps of: providing a substrate, the substrate having an upper surface and a lower surface, wherein the upper surface has at least one sticky crystal region, the A circuit layer is formed on the lower surface, and the die-bonding region has at least one window penetrating through the substrate; point adhesive is applied on the die-bonding region of the substrate; a wafer is contacted with the die-bonding region of the substrate, and the wafer has The active surface of the bonding pad contacts the adhesive on the die attach region of the substrate, and a predetermined pressure is applied to adhere the wafer to the substrate, wherein the bonding pad of the wafer corresponds to the window; heating to cure the adhesive; and through the window A wire is electrically connected to the pad of the wafer and the substrate; a thermosetting sealant is formed, the sealant system seals the metal wire; and a solder ball is implanted, and the solder ball is implanted on a circuit layer on the lower surface of the substrate. 2. According to the semiconductor packaging process described in item 1 of the scope of patent application, the adhesive is applied to the die attach area by means of dispensing. 3. The semiconductor packaging process as described in item 1 of Shenyan's patent scope, wherein the adhesive is applied on the die attach area by means of glue. 4. The semiconductor packaging process described in item 1 of the scope of patent application, wherein the adhesive is a thermosetting or thermoplastic adhesive. 5. The semiconductor packaging process as described in item 4 of the patent application, wherein the adhesive is an epoxy adhesive or an Ag-epoxy adhesive. 6. The semiconductor packaging process as described in item 1 of the scope of patent application, wherein 518732 VI. Scope of patent application The temperature for curing the adhesive is about 15 0 c to 17 5 c. 7. The semiconductor sealing process as described in the scope of the patent application, wherein the circuit layer on the lower surface of the substrate includes at least one conductive pad. 8. The semiconductor packaging process as described in item 7 of the scope of the patent application, wherein the pads of the chip are electrically connected to the bottom surface of the substrate with the metal wires. 9. According to the semiconductor packaging process described in item 丨 of the patent application scope, the solder balls in the basin are arranged in a matrix to form a ball grid array semiconductor packaging structure.