TWI223974B - Tiny memory card and method for manufacturing the same - Google Patents

Abstract

A tiny memory card comprises a chip, a plurality of outer terminals and a polymer passivation layer. A plurality of connection pads are formed on the active surface of the chip. Each outer terminal includes a UBM layer and an Au-plating layer on the connection pads. The polymer passivation layer is formed on the active surface of the chip for steadying the outer terminals. So the memory card has a tiny design.

Description

1223974

In particular, the invention relates to a fifth, description of the invention (1) [Technical Field to which the Invention belongs] Wafer The present invention relates to a memory card grade micro memory card and a method for manufacturing the same. [Previous technology]: It is known that the memory card is a flat card, such as X " memory card, S, Med memory card CF memory ... ίΐίΐ There is no need to make any solder ball bumps or pins on the outside of the memory card. A conventional memory card includes at least one control circuit, a circuit substrate, and a plastic case; the written circuit is provided on the circuit substrate. The gastric memory chip is formed by: The substrate packaging process assembles the chip and the circuit board, and then uses a module assembly step to combine the circuit board with the ^ memory chip in the plastic case. The overall thickness and size are not easy to achieve a miniaturized design. For example, Yi Yi: [young Pi-card], the smallest size can only reach = own X Z5x 1.7min °

In U.S. Patent No. 55 1 4856, the prior art discloses that a conventional memory card includes a "chip, a circuit board, and a plastic shout, and a chip is mounted on the circuit board and sealed." After that, the circuit substrate is flipped and bonded to the cavity of the plastic case. The US Patent No. 5 51 4 = 6 proposes an improved method for manufacturing a memory card. The memory card includes a chip, a substrate and a resin sealing layer. The memory card is used to guide a contact pad of a card reader. The contact pads are connected to the substrate. The contact pads are disposed on one surface of the substrate and a semiconductor is disposed on the other surface of the substrate.

1223974 V. Description of the invention (2) Wafer and the resin sealing layer, made of A

Ab and II. In the manufacturing process, the XA person's resin sealing layer is continuously extended and formed on the unit substrate [_ substrate] containing a plurality of substrates, and then the resin is cut and sealed to the fluorescein-A ι »Components, but still need to put individual chips =: = board can not reach the size of the chip size memory card. The type is to provide a micro memory card, the micro R is composed of-ϋΒΜ, [under the bump metal layer, Under] and a gold-plated layer and is connected to a chip 'to omit the conventional memory card substrate and plastic The housing and other components meet the miniaturization requirements of the Chip Scale Car cSC. < The second purpose of the micro-f invention is to provide a micro memory card, which is formed on the active surface of a chip with a plurality of external connection terminals and a high protection layer, and the molecular protection layer is connected to the external connections. The gold-plated layers of the terminals are coplanar to enhance the protection of the external connection terminals. Another object of the present invention is to provide a micro memory card, wherein the UBM layer includes at least an adhesive layer and a barrier, and the UBM layer and a gold layer form an outer connecting end of the micro memory card, and the adhesive layer And the barrier layer ^ between the connection pad of a wafer and the gold-plated layer to stabilize the gold-plated layer to prevent metal diffusion, so that the gold-plated layer is not easy to fall off the wafer. " Another object of the present invention is to provide a method for manufacturing a micro memory card. A wafer-level packaging process is used to fabricate an active surface of a wafer = a plurality of external connection terminals including a UBM layer and a gold plating layer, and One Polymer Recovery ^

V. Description of the invention (3) ί 数 ί The ΐ Jing unitized along the cutting line of the wafer and separated it, and became a Siri memory card to achieve wafer-level manufacturing of memory cards, which is omitted ° Hidden card's substrate packaging steps for individual chips and module assembly steps for plastic housings. Another object of the present invention is to provide a manufacturer 2 of a micro memory card, which is in a wafer-level packaging process, and the connection pads of adjacent wafers are integrally connected on both sides of a cutting line of a wafer to The UBM layer and the gold-plated layer are formed on a plurality of external connection ends. The micro memory card according to the present invention mainly includes a chip, a plurality of external connection ends, and a polymer protective layer. The chip has an active surface and a corresponding back surface, and the active surface is formed with a plurality of connection pads. And a protective layer, preferably, the connection pads are connected to a cutting line of a wafer in a wafer-level packaging process, and are formed on one side of the active surface, and each outer connection end includes a UBM Layer [Under Bump Metal lurgy] and a gold-plated layer, wherein the UBM layer is covered by a lithography imaging technology on the corresponding connection pad, and the gold-plated layer is formed on the UBM layer, preferably Ground, the UBM layer is composed of an adhesive layer, a barrier layer and a fusion layer, and it is preferable to partially cover the protective layer, and the polymer protective layer is formed on the active surface of the wafer. The polymer protective layer is selected from one of a solder mask, an organic passivation layer, and a dry film. In one embodiment, the polymer protective layer is Tied to the External connections of the gold plating layer coplanar. [Embodiment]

Page 7 1223974 V. Description of the Invention (4) '--With reference to the attached drawings, the present invention will enumerate the following embodiments. ^ According to a specific embodiment of the present invention, please refer to FIGS. 1 and 2. A micro memory card system mainly includes a chip 丨 0, a plurality of external connection terminals 20, and a polymer protective layer 30. The chip 丨〇 series has an active surface 丨 丨 and a corresponding back surface 12, the chip 1 0 can be a semiconductor, plastic or glass material, preferably 'the chip 1 0 is a system-on-chip ], Which includes a non-volatile memory unit and an Input / Output control unit or a decoding unit. It is fabricated on the active surface 11 by using integrated circuit manufacturing process. Among them, the more common non-volatile memory unit is faster. In addition, a plurality of connection pads 13 and a protective layer 14 are formed on the active surface. The connection pads 13 are arranged on the external connection ends of the micro memory card by a redistribution process. 2 〇. Each of the outer connection ends 20 of the present invention includes a UBM layer 21 [Unbump Metal lurgy] and a gold plating layer 22, and the UBM layer 21 is formed on the connection pad 13 of the wafer 10 It is different from the external connection end of the conventional memory card. The external connection end is arranged on a substrate or a metal pad of a plastic casing (not shown). The UBM layer 21 is patterned and covered with a photolithography technology. On the connection pad 13, the gold-plated layer 22 is formed on the UBM layer 21. The UBM layer 21 is a composite metal layer, which includes an adhesive layer 2 11 and a barrier layer 2 1 2. The adhesive layer 2 11 covers the connection pads 13 corresponding to ❿, and the material of the adhesive layer 2 11 can be titanium, titanium tungsten alloy, Shao or chrome, to enhance the connection with the connection pads 13, according to the external connections The exposed area of the gold-plated layer 22 at the end 20 is different, and the adhesive layer 211 can be more partially covered to the protective layer 14 to expand the formation surface of the gold-plated layer 22.

Page 1223974 V. Description of the invention (5), and the barrier layer 2 1 2 is covered on the adhesive layer 2 1 1, and the material of the barrier layer 212 may be nickel alloy, copper alloy or copper alloy. To prevent the metal plating layer 22 from diffusing to the corresponding connection pad 13 and damaging the wafer 10, preferably, the UBM layer 21 further includes a fusion layer 213 formed on the barrier layer 212, the The material of the fusion layer 213 may be copper, palladium, or gold to promote the bonding of the gold-plated layer 22 to the barrier layer 2 1 2. The gold-plated layer 2 2 is formed on the UBM layer 21 by means of electrical bonding. Alternatively, the mineral gold layer 22 may be formed on the connection pads 13 and have a surface exposed on the active surface η of the chip as a conductive surface of the external connection ends 20. Preferably, the gold plating layer The 22 series makes the external connection ends 20 expand and protrude from the active surface 11 of the chip 10 for conductive contact of the card connector of external electronic products. Then, the polymer protection layer 30 is formed on the active surface 11 ′ of the wafer 10 to protect the wafer 10 and has the effect of preventing the external connection ends 20 from being too convex and easy to fall off, and the polymer The protective layer 30 has a plurality of openings 31 ′, which are used to expose the gold-plated layer 22 of the external connection ends 20, and the polymer protective layer 30 is selected from the solder resist layer [s〇i (ier mask ], One of an organic passivation layer and a dry film. In this specific embodiment, the polymer protective layer 30 is a gold-plated layer 22 connected to the external connection ends 20. Coplanar, or the gold-plated layer 22 can be lower than the polymer protective layer 30, and the polymer protective layer 30 can be used to effectively stabilize the external connection terminals 20. Therefore, the micro memory card of the present invention uses "The external connection terminal 20 is composed of a UBM layer 21 and a gold-plated layer 22 and is directly provided on the connection pad 13 of the chip 10", in order to omit the substrate and

Page 9 1223974 V. Description of the invention (6)

Plastic cti = r becomes "required, this micro memory card is W" = t, e, cri: $ jcsc], its size can reach 15x15χ size memory card to achieve the effect of miniaturization of 7 cards, the so-called "chip point five times, It is': the size of 2 cards is not larger than 10 areas of the chip-one, the function of the micro memory card of the present invention: two li is used to limit the component type of the present invention, because the chip 10 In ", the conventional thinning and etching technology is used to make the wafer 10 size, and the manufacturing method of the micro memory card can use the wafer level packaging process to omit the conventional memory card for individual The steps for assembling the module of the substrate and the shell of the wafer are detailed as follows. Regarding the manufacturing method of the above micro memory card, Figs. 3 to 6 are schematic diagrams of partial cross-sections of wafers not used in the manufacturing process, please refer to the 3 Figures. First, a wafer 50 is provided. The wafer 50 includes a plurality of integrated wafers, as described above, the wafer i 0 and the cutting lines 51 between the wafers i 0, and a mother piece 10 Has an active surface and a corresponding back 12. The active surface 1 of each chip 10 is formed with a plurality of connection pads 3 and a protective layer 14. In this embodiment, in a wafer-level packaging process, the adjacent chips 10 should The connection positions of the connection pads 13 are connected to the cutting line 5 丨 of the wafer 50, and are formed on one side of the corresponding active surface 11. The protective layer 14 exposes these connections of two adjacent different wafers 10. Pad 丨 3; then, referring to FIG. 4, using sputtering and other methods to form the adhesive layer 2 1 1, the barrier layer 2 1 2 and the fusion layer on the active surface 11 of the wafer 50. 2 1 3, and optionally cooperate with photolithography and post-etching technology to etch the adhesive layer 2 11, the barrier layer 21 2 and the fusion layer 2 1 3

Page 10 1223974 V. Description of the invention (7) The plurality of UBM layers 21 covering the corresponding connection pads 13, or the 或者 BM layer 21 may also be formed with the gold-plated layer 22 as a cover [ mask] The UBM layer 21 is formed into a pad shape by etching or the like, [not shown in the figure]; afterwards, 'refer to FIG. 5 and use spin coating, dry film attachment or printing technology on the wafer 5 The active surfaces 11 form the polymer protective layer 30. The polymer protective layer 30 has a plurality of openings 31, and the openings 31 correspond to the connection pads 3 to expose the Some UBM layers 21; after

The gold plating layer 22 is formed on the UBM layer 21. In this embodiment, the cutting lines 51 of the wafer 50 are electrically connected to the connection pads 13, which can be used as the electroplated connection lines of the gold gold layers 22. Preferably, after the gold-plated layer 22 is formed, a planarization grinding step may be applied to make the polymer protective layer 30 and the 4 plated layers 22 coplanar; most |, along the cutting lines 51 single Separate the wafer 50 ° in size to manufacture the above-mentioned miniature chip as shown in Figures j and 2 at the wafer level: "In the present invention, the conventional memory card is omitted to seal the substrate of individual wafers: Bu The module assembly steps of the shell 'preferably, connect the M # electrode processing or plating in a single vessel to

~ Tailu or the exposed surface of the UBM layer 21 forms a resist protection film. The scope of the guarantee δ of A m is only defined by the scope of the attached patent application; 2 It is known to the person skilled in the art that any changes and modifications that do not depart from the spirit of the present invention belong to the protection scope of the present invention.

1223974 Brief description of the drawings [Simplified description of the drawings] FIG. 1 • A schematic cross-sectional view of a micro memory card according to a specific embodiment of the present invention; FIG. 2: A micro memory card according to a specific embodiment of the present invention Schematic diagram of the surface with external connection ends; and Figures 3 to 6 according to the micro memory card manufacturing method of the present invention, the cross-section of the wafer used to manufacture the micro memory card in the manufacturing process is not intended. Component symbols are simply explained ! 10 Chip 11 Active surface 12 Back 13 Connection pad 14 Protective layer 20 Outer connection end 21 UBM layer 22 Gold plating layer 211 Adhesive layer 212 Barrier layer 213 Fusion layer 30 South molecular protective layer 31 Opening hole 50 Wafer 51 Cutting line

Page 12

Claims (1)

1223974 VI. Scope of patent application [Scope of patent application] 1. A micro memory card, including a chip, which has an active surface and a corresponding back surface, the moving surface is formed with a plurality of connection pads and a protective layer ; A plurality of external connection terminals, each of which includes a UBM layer (under bump metal layer, Under Bump Metallurgy) and a gold recording layer, wherein the UBM layer covers the corresponding connection pad, the gold plating layer is On the UBM layer; and onan molecular protective layer 'which is formed on the active surface of the wafer. 2. The micro memory card according to item 1 of the scope of patent application, wherein the polymer protective layer is coplanar with the gold-plated layer. ^ Some of which, which of which, which of which, which of which is high 3. The micro memory card UBM layer as described in item 1 of the scope of patent application is partially covered to the protective layer of the chip. 4. The external connection end of the micro memory card described in item 1 of the scope of patent application is located on one side of the active surface of the chip 5. The UBM layer of the micro memory card described in item 1 of the scope of patent application contains a Adhesive layer and a barrier layer. 6. The micro memory card described in item 5 of the patent application, the BM layer further includes a fusion layer. 7. The micro memory card according to item 1 of the scope of patent application. Cavity τ soft meat The molecular protective layer is selected from one of a solder resist layer, an organic protective layer, and a photosensitive dry film. 8. The micro memory card according to item 1 of the scope of patent application, wherein the chip system includes a non-volatile memory unit and a control unit. Page 13 1223974 9 pinch! The micro memory card according to item 8 of the patent, wherein the non-volatile memory unit is a flash memory. 10 micro = 2 micro memory card as described in the eighth item, wherein the size of the 11 1 Ϊ card is not more than five times the area of the chip. 11. A method for manufacturing a micro memory card, comprising: providing a wafer, the wafer system comprising a plurality of wafers and a cutting line between the wafers, each wafer having an active surface and a corresponding back surface The active surface is formed with a plurality of connection pads and a protective layer; a UBM layer (under bump metal layer, Under Bump Metal lurgy) is formed on the active surfaces of the wafers, and the UBM layer is patterned to cover the corresponding surface. A connection pad; forming a polymer protection layer on the active surface of the wafer, the polymer protection layer having a plurality of openings corresponding to the connection pads; forming a gold plating layer on the UBM layer; and The wafer is singulated along the dicing lines. 1 2. The method of manufacturing a micro memory card according to item 11 of the scope of the patent application, wherein the polymer protective layer and the forged gold layer are coplanar. 1 3. The method of manufacturing a micro memory card according to item 11 of the scope of patent application, wherein in the step of providing the wafer, the connection pads of adjacent wafers are connected to each other. 14. The method for manufacturing a micro memory card according to item 1 or item 13 of the scope of patent application, wherein in the step of forming the UBM layer, 1223974 VI. Scope of patent application The UBM layers on the connection pads are connected to each other. 15. The method for manufacturing a micro memory card according to item π of the scope of patent application, wherein the UBM layers are partially covered to the protective layer of the chip. 16. The method for manufacturing a micro memory card according to item 1 丨 in the scope of the patent application, wherein the UBM layer includes an adhesive layer and a barrier layer. 17. The method for manufacturing a micro memory card according to item 16 of the scope of patent application, wherein the UBM layer further comprises a fusion layer. 18. The method for manufacturing a micro memory card according to item 11 of the scope of the patent application, wherein the polymer protective layer is selected from one of a solder resist layer, an organic protective layer, and a photosensitive dry film. '1 9. The method for manufacturing a micro memory card as described in item 丨 丨 of the patent application range', wherein the chip includes a non-volatile memory unit and a control unit. Wangshi J20. The method for manufacturing a micro memory card as described in item 19 of the scope of patent application, wherein the non-volatile memory unit is a flash memory. w 21. A micro memory card comprising: 'a chip having an active surface and a corresponding back surface, the active surface is formed with a plurality of connection pads and a protective layer; ^ a plurality of external connection terminals, each The outer connection end includes a connection layer formed on the connection pads; and a polymer protection layer formed on the active surface of the chip. 22 2. A micro memory card as described in item 21 of the scope of patent application. The polymer protective layer is coplanar with the gold-plated layer. Zhongzhong 23. The miniature notebook as described in item 21 of the scope of patent application, where ^ 3974 VI. Scope of patent application The external connection terminals are located on one side of the active surface of the chip. 24. The micro memory card according to item 21 of the patent application scope, wherein the polymer protective layer is selected from the group consisting of a solder resist layer, an organic protective layer, and a photosensitive dry film *. 25. The micro memory card according to item 21 of the scope of the patent application, wherein the tablet system includes a non-volatile memory unit and a control unit. 26. The micro memory card as described in item 25 of the patent application scope, wherein the non-volatile memory unit is a flash memory. 27. A method for manufacturing a micro memory card, comprising: providing a wafer, the wafer system comprising a plurality of wafers and a cutting line between the wafers, each wafer having an active surface and a corresponding On the back side, the active surface is formed with a plurality of connection pads and a protective layer; a polymer protective layer is formed on the active surface of the wafer, and the polymer protective layer has a plurality of openings corresponding to the connection pads; A layer of mineral gold is on the connection pads; and the wafer is singulated separately along the cutting lines. 28. The method of manufacturing a micro memory card as described in item 27 of the scope of the patent application, wherein the two molecular protective layers are coplanar with the non-bonded gold layer. 29. The method for manufacturing a micro memory card according to item 27 of the scope of patent application, wherein in the step of providing the wafer, the connection pads of adjacent wafers are connected to each other. 30. The method for manufacturing a micro memory card as described in item 27 of the scope of the patent application, wherein the polymer protective layer is selected from a solder resist layer and an organic protection layer. Page 16 1223974 6. Scope of patent application One of the layer and photosensitive dry film. 3 1. The method of manufacturing a micro memory card as described in item 27 of the scope of patent application, wherein the chip includes a non-volatile memory unit and a control unit. 3 2. The method for manufacturing a micro memory card as described in item 31 of the scope of patent application, wherein the non-volatile memory unit is a flash memory.