Wire bonding device and bonding method for implantable microelectronic products

Abstract

The present invention relates to a wire bonding device and bonding method for an implantable microelectronic product, comprising a plurality of wire connectors buried in a packaging base, one end of the wire connector being connected to a chip disposed between the packaging base and a shell, and the other end being provided with a card slot, the card slot being used to fix the end of a cable arrangement, the end of the cable arrangement having a protruding structure, and the middle section of the cable arrangement being pressed between the packaging base and the shell. The present invention does not involve single-point processing during processing, the connection process is carried out by accurately aligning the card slot and the end, and physically embedding at a fixed position, the connection rate is high, the bonding area required for welding is small, and the bonding strength is safe and stable. The card slot design avoids the diffusion of solder at the interface of the base, prevents unnecessary short circuits, and realizes the reliability of circuit connectivity. The various components of the present invention have good biocompatibility, and multiple biocompatible coatings are deposited to ensure safety and reliability after implantation, and the cable arrangement and the corresponding wire connector are quickly connected at a low cost.

Description

Technical Field

[0001] The invention relates to a wire bonding device and a bonding method for an implantable microelectronic product, belonging to the technical field of biomedical engineering. Background Art

[0002] Microelectronic products have become an indispensable part of our lives. With the development of science and technology, microelectronic products have played an important role in the medical field. They are effective tools for establishing connections between humans or animals and external devices, and can treat and monitor specific diseases more directly and accurately. Implantable electronic products need to be packaged to connect with each other to provide signal transmission. Long-term safe and effective connection methods have become the research goals of various scientific and technological workers, and relevant research in this field has made many breakthroughs worldwide.

[0003] At present, in the biomedical field, there are still many problems in wire bonding. Wire bonding is the next process after chip mounting is completed. Wire bonding is a technology for interconnecting the chip with the external circuit. Usually, fine metal wires are used to connect the I / O metal solder joints on the chip and the corresponding wire solder feet on the package. The existing wire bonding technology has the problem of low connection rate during point-to-point processing, complex micro-wire connection alignment, and affects the alignment accuracy of multiple wires; the large bonding area required for welding, and the diffusion of solder metal at the interface may cause short circuits. In addition, micro devices implanted in the human body must not only ensure good connections, but also have strict requirements on the selection of materials for various devices. Within the specified service life, the effective transmission of signals by the wire is an important indicator of the working reliability of the micro device. This requires not only a stable connection of the wire, but also the integrity of the wire protective layer, so that no damage to human tissue will occur due to the exposure of the wire. The wire bonding process is relatively complicated and costly, which is also the reason for limiting the promotion and use of micro devices in the field of bioengineering. Summary of the invention

[0004] The technical problem to be solved by the present invention is: to overcome the above problems, a wire bonding device and a bonding method for an implantable microelectronic product are provided.

[0005] The technical solution adopted by the present invention to solve its technical problem is:

[0006] A wire bonding device for an implantable microelectronic product comprises a plurality of wire connectors buried in a packaging base, wherein one end of the wire connector is connected to a chip disposed between the packaging base and a shell, and the other end of the wire connector is provided with a slot for fixing an end of a cable. The end of the cable has a protruding structure, and the middle section of the cable is pressed between the packaging base and the shell.

[0007] Preferably, the wire connector is interconnected with the end of the cable in the slot by welding with a small amount of solder.

[0008] Preferably, the interior of the cable is a biocompatible metal wire, the exterior of the metal wire is wrapped with an insulating coating, and the outermost surface of the metal wire is wrapped with a flexible biocompatible polymer material layer.

[0009] Preferably, a welding groove is further provided inside the clamping groove of the wire connector.

[0010] Preferably, the housing is hermetically bonded to the packaging substrate by biocompatible adhesive bonding, laser welding, vacuum brazing or eutectic bonding.

[0011] Preferably, the outer sides of the shell and the packaging base are also wrapped with a biocompatible coating.

[0012] Preferably, one end of the wire connector is connected to the chip by flip-chip welding.

[0013] A wire bonding method for an implantable microelectronic product as described above comprises the following steps:

[0014] S1: pre-embed a plurality of wire connectors in the package base, and connect the chip to one end of the wire connector by flip-chip bonding;

[0015] S2: After physically inserting the end of the flat cable into the slot of the wire connector, a small amount of solder is applied to the contact point between the two or the two are directly connected;

[0016] S3: Finally, the housing is sealed and bonded to the package base.

[0017] Preferably, the step S3 specifically comprises: the shell is hermetically bonded to the packaging substrate by methods such as biological glue bonding, laser welding, vacuum brazing or eutectic bonding.

[0018] Preferably, the method further comprises step S4: wrapping the outer sides of the shell and the packaging base with a biocompatible coating.

[0019] The beneficial effects of the present invention are:

[0020] (1) The present invention does not involve single-point processing during processing. The connection process is carried out by accurately aligning the card slot and the terminal, and physically embedding at a fixed position. The connection rate is high, the bonding area required for welding is small, and the bonding strength is safe and stable. The card slot design avoids the diffusion of solder at the base interface, prevents unnecessary short circuits, and achieves the reliability of circuit connectivity.

[0021] (2) The wires can effectively transmit signals within the specified implantation period, and each component has good biocompatibility. Biocompatible coatings are deposited multiple times to ensure the safety and reliability of the implant.

[0022] (3) The pre-buried wiring and the corresponding wire connectors are quickly connected at a low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0024] Figure 1 It is a partial structural schematic diagram of an embodiment of the present invention;

[0025] Figure 2 A schematic diagram of an embodiment of the wire connector described in this embodiment;

[0026] Figure 3 is a partial structural schematic diagram of another embodiment of the present invention;

[0027] Figure 4 A schematic diagram of another embodiment of the wire connector described in this embodiment;

[0028] Figure 5 It is a schematic diagram of the arrangement of the wiring of the present invention.

[0029] Markings in the figure: 1-chip, 2-housing, 3-cable, 4-card slot, 5-wire connector, 6-package base, 7-solder ball, 31-terminal, 51-soldering groove. DETAILED DESCRIPTION

[0030] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0031] Example 1

[0032] like Figure 1 The wire bonding device of an implantable microelectronic product of the present invention shown in the figure comprises a plurality of wire connectors 5 embedded in a package base, one end of the wire connector 5 is electrically connected to a chip 1 disposed between the package base and a housing 2, the number of the wire connectors 5 is set according to the connection points of the chip 1, and the position is set correspondingly according to the position of the connection points of the chip 1, and the other end thereof is provided with a card slot 4, preferably as Figure 1 and Figure 2 As shown, the slot 4 is formed by digging a groove on the wire connector 5 , and the slot 4 is used to fix the end 31 of the flat cable 3 , and the middle section of the flat cable 3 is pressed between the packaging base and the housing 2 .

[0033] In a preferred embodiment, the slot 4 of the wire connector 5 and the terminal 31 of the flat cable 3 are melt-welded by a trace amount of solder, and the solder is preferably a low-melting-point lead-free solder SnBiX. There is no single-point processing during the processing of the present invention. The connection process is carried out by accurately aligning the slot 4 and the terminal 31, and physically embedding them in a fixed position. The connection rate is high, the bonding area required for welding is small, and it has a safe and stable bonding strength. The design of the slot 4 avoids the diffusion of solder at the base interface, prevents unnecessary short circuits, and achieves the reliability of circuit connectivity.

[0034] In a preferred embodiment, the interior of the flat cable 3 is a biocompatible metal wire, such as Ti, Pt, Au, Ti6Al4V, Ptlr, 316L, etc. In order to reduce the harm caused by the leakage of the metal wire due to the rupture of the wrapping layer, the outside of the metal wire is first insulated, such as depositing parylene-C, etc. The outside of the biocompatible metal wire is wrapped with one or more flexible biocompatible polymer material layers, such as PI or silica gel, which can further effectively reduce the harm caused by the flat cable 3 in the human body and reduce irritation.

[0035] In a preferred embodiment, the wire connectors 5 are evenly spaced around the package substrate 6. The evenly spaced arrangement can avoid mixed connections and facilitate the wiring of the cable 3, but it is not limited to this. When the chip 1 interfaces are densely packed in some places, the wire connectors 5 can also be densely packed accordingly. Figure 5 As shown, the end 31 of the flat cable 3 is set according to the position of the wire connector 5, and the tail ends thereof can be bundled together, making it more convenient to connect with an external controller.

[0036] In a preferred embodiment, the housing 2 is sealed and bonded to the packaging substrate 6 by bio-adhesive bonding or laser welding. The sealed packaging ensures the sealed use of the chip 1, ensures its service life, and avoids the risk of harm to the human body due to damage and leakage.

[0037] In a preferred embodiment, multiple layers of biocompatible coatings, such as parylene-C, PI, silica gel, etc., are deposited on the outer sides of the shell 2 and the packaging base to further reduce irritation and harm to the human body.

[0038] In a preferred embodiment, one end of the wire connector 5 is connected to the chip 1 by welding with a solder ball 7, thereby strengthening the connection strength between the wire connector 5 and the chip 1 and ensuring smooth electrical connection and long-term stable use.

[0039] Example 2

[0040] In this embodiment, if Figure 3The wire bonding device of an implantable microelectronic product of the present invention shown in the figure comprises a plurality of wire connectors 5 embedded in a package base, one end of the wire connector 5 is connected to a chip 1 disposed between the package base and a housing 2, the number of the wire connectors 5 is set according to the connection points of the chip 1, and the position is set correspondingly according to the position of the connection points of the chip 1, and the other end thereof is provided with a card slot 4, preferably as Figure 3 and Figure 4 As shown. A welding groove 51 is also formed inside the card slot 4, wherein the card slot 4 is used to fix the end 31 of the flat cable 3. The fixing groove 51 is filled with the same material as the packaging shell 2. This embodiment can solve the defect of incompatible packaging interface and provide a guarantee of airtight packaging.

[0041] Example 3

[0042] In this embodiment, a wire bonding method for an implantable microelectronic product is provided, comprising the following steps:

[0043] S1: a plurality of wire connectors 5 are pre-buried in the package base. In specific implementation, the base material of the package base and the wire connector are formed by melting or sintering at one time, which has good mechanical properties. The chip 1 is electrically connected to one end of the wire connector 5 by flip-chip welding;

[0044] S2: After the end 31 of the flat cable 3 is physically embedded in the slot 4, a trace amount of solder is melted and welded at the contact point between the two. The trace amount of solder melted welding method is a well-known technical means in the welding field. In the present invention, the trace amount of solder melted welding has a low melting point and small diffusion, and needs to maintain an effective connection for a long time.

[0045] S3: Finally, the housing 2 is sealed and bonded to the packaging base to further ensure the overall sealing.

[0046] In a preferred embodiment, step S3 is specifically as follows: the shell 2 is bonded to the packaging base by means of biological glue, such as epoxy system ceramic adhesive, silicone system adhesive, acrylic system adhesive, silicate adhesive or phosphate adhesive, and the biological glue is applied at the connection between the two, and then aligned for bonding, or laser welding is used to weld the contact between the shell 2 and the packaging substrate 6 for sealing and bonding.

[0047] In a preferred embodiment, the method further comprises step S4: depositing a biocompatible coating on the outer sides of the housing 2 and the packaging base, wherein the biocompatible coating preferably has a thickness of 50 microns and is covered three times.

[0048] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A wire bonding device for an implantable microelectronic product, characterized in that: It includes a plurality of wire connectors buried in the package base, one end of the wire connector is connected to a chip arranged between the package base and the shell through a solder ball, and the other end is provided with a slot, which is used to fix the end of the cable. A welding groove is also provided on the inner side of the slot of the wire connector, the end of the cable has a protruding structure, and the middle section of the cable is pressed between the package base and the shell.

2. The wire bonding device for an implantable microelectronic product as claimed in claim 1, characterized in that: The wire connector is interconnected with the end of the cable in the slot by welding with a small amount of solder or by direct contact.

3. The wire bonding device for an implantable microelectronic product as claimed in claim 1, characterized in that: The interior of the cable is a biocompatible metal wire, the exterior of the metal wire is wrapped with an insulating coating, and the outermost surface of the metal wire is wrapped with a flexible biocompatible polymer material layer.

4. The wire bonding device for an implantable microelectronic product according to any one of claims 1 to 3, characterized in that: The shell is hermetically bonded to the packaging substrate by means of biocompatible adhesive bonding, laser welding, vacuum brazing or eutectic bonding.

5. The wire bonding device for an implantable microelectronic product as claimed in claim 4, characterized in that: The outer sides of the shell and the packaging base are also wrapped with a biocompatible coating.

6. The wire bonding device for an implantable microelectronic product as claimed in claim 1, characterized in that: One end of the wire connector is connected to the chip through flip-chip welding.

7. A bonding method for a wire bonding device for an implantable microelectronic product as claimed in any one of claims 1 to 6, characterized in that: The following steps are involved: S1: pre-embed a plurality of wire connectors in the package base, and connect the chip to one end of the wire connector by flip-chip bonding; S2: After physically inserting the end of the flat cable into the slot of the wire connector, a small amount of solder is applied to the contact point between the two or the two are directly connected; S3: Finally, the housing is sealed and bonded to the package base.

8. The wire bonding device for an implantable microelectronic product as claimed in claim 7, characterized in that: The step S3 specifically comprises: the shell is hermetically bonded to the packaging substrate by means of biological glue bonding, laser welding, vacuum brazing or eutectic bonding.

9. The wire bonding device for an implantable microelectronic product as claimed in claim 7, characterized in that: The method further comprises step S4: wrapping the outer sides of the shell and the packaging base with a biocompatible coating.

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