Electromagnetic shielding wire and electromagnetic shielding structure

Abstract

The utility model provides an electromagnetic shielding wire and an electromagnetic shielding structure, and relates to the technical field of semiconductor packaging. The electromagnetic shielding wire comprises a first end part, a main body part and a second end part, wherein the first end part is used for being connected with a metal bonding pad on a substrate. The main body part is connected to the first end part, and the main body part is provided with one or more bending sections. The second end portion is arranged at one end of the body portion away from the first end portion. The offset of the center of the first end part and the center of the second end part in the X direction is 1 [mu] m to 2 mm, and the offset of the center of the first end part and the center of the second end part in the Y direction is 1 [mu] m to 2 mm. The X direction is perpendicular to the Y direction. The contact area of the electromagnetic shielding wire and the plastic package body is increased, and the binding force is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor packaging, and in particular, to an electromagnetic shielding wire and an electromagnetic shielding structure. Background Art

[0002] With the rapid development of the semiconductor industry, the system-level packaging module structure is widely used in the semiconductor industry. After different functional chips are packaged, they are stacked. The main advantages are high-density integration, small size of the packaged product, excellent product performance, fast signal transmission frequency, etc. As electronic products are applied to high-frequency signals in the communication field, there is a need for products to have a partitioned electromagnetic shielding structure to prevent electromagnetic interference generated by various chips and components from affecting each other. The existing partitioned shielding technology mainly uses wire bonding to form a cage-shaped shielding structure.

[0003] The cage-shaped shielding structure is to wire in the substrate and form a ground pad on the substrate surface. The ground pad is located around the chips or components to be shielded. Vertical metal wires are bonded on the ground pad, and the vertical metal wires surround the chips or components to be shielded, thereby forming a cage-shaped shielding structure.

[0004] The inventor has found through research that the existing vertical metal wires are prone to deformation under the influence of molding in the subsequent plastic encapsulation process, and there is a large difference in the thermal expansion coefficient between the vertical metal wires and the plastic encapsulant, which easily leads to structural delamination and affects the packaging reliability. Summary of the Utility Model

[0005] The purpose of the utility model is to provide an electromagnetic shielding wire and an electromagnetic shielding structure, which can help improve the bonding force between the electromagnetic shielding wire and the plastic encapsulant and improve the packaging reliability.

[0006] The embodiments of the utility model are implemented as follows:

[0007] In a first aspect, the utility model provides an electromagnetic shielding wire, comprising:

[0008] A first end portion for connecting to a metal pad on a substrate;

[0009] A main body portion connected to the first end portion, the main body portion being provided with one or more bending segments; the maximum offset of the center line of each bending segment relative to the center of the first end portion is 1 um to 2 mm;

[0010] A second end portion provided at one end of the main body portion away from the first end portion;

[0011] The offset between the center of the first end portion and the center of the second end portion in the X direction is 1 um to 2 mm, and the offset in the Y direction is 1 um to 2 mm; the X direction is perpendicular to the Y direction.

[0012] In an optional embodiment, the distance between the first end and the second end is 100 um to 2 mm.

[0013] In an optional embodiment, the turning angle of each bending section is 10° to 150°.

[0014] In an optional embodiment, the bending segment includes an arc segment and / or a broken line segment.

[0015] In an optional embodiment, the bending segment includes a first arc segment, a second arc segment and a third arc segment connected in sequence; the bending directions of the first arc segment and the second arc segment are opposite, and the bending directions of the first arc segment and the third arc segment are the same.

[0016] In an optional embodiment, the curvature of the third arc segment is smaller than the curvature of the first arc segment.

[0017] In an optional embodiment, the angle between the tangent direction of the second end and the vertical direction is 0.5 degrees to 60 degrees.

[0018] In an optional embodiment, the first end portion, the main body portion and the second end portion are integrally formed.

[0019] In a second aspect, the present invention provides an electromagnetic shielding structure, comprising a substrate, a chip, a plastic package, a shielding layer, and an electromagnetic shielding wire as described in any one of the aforementioned embodiments, wherein the chip is provided on the substrate, and the chip and the substrate are electrically connected;

[0020] A metal pad is provided on the substrate, the electromagnetic shielding wire is connected to the metal pad, and the electromagnetic shielding wire is located at the periphery of the chip;

[0021] The plastic package wraps the chip and the electromagnetic shielding wire, and the electromagnetic shielding wire is exposed from the surface of the plastic package;

[0022] The shielding layer is arranged on the surface of the plastic package body and is electrically connected to the electromagnetic shielding wire.

[0023] In an optional embodiment, a ground wiring layer is provided in the substrate, and the metal pad is electrically connected to the ground wiring layer;

[0024] And / or, the ground wiring layer extends to the cutting street, is exposed from the side wall of the substrate, and is electrically connected to the shielding layer.

[0025] The beneficial effects of the embodiments of the present utility model include:

[0026] The electromagnetic shielding wire provided by the embodiment of the present utility model is provided with a plurality of bending segments on the main body part, which can increase the contact area between the electromagnetic shielding wire and the plastic encapsulation body, thereby helping to improve the bonding force between the shielding wire and the plastic encapsulation body, preventing the occurrence of structural delamination, and improving the packaging reliability. In addition, the main body part is provided with a plurality of bending segments, which can change the stress points of the main body part, improve the bearing capacity of the main body part, and relieve the deformation or fracture of the electromagnetic shielding wire caused by die pressing.

[0027] The electromagnetic shielding structure provided by the embodiment of the present utility model includes the above-mentioned electromagnetic shielding wire, which is beneficial to increasing the contact area between the electromagnetic shielding wire and the plastic encapsulation body, improving the bonding force between the shielding wire and the plastic encapsulation body, preventing the occurrence of structural delamination, and improving the packaging reliability. It can avoid the deformation or fracture of the electromagnetic shielding wire affected by die pressing, ensure the uniform spacing between adjacent electromagnetic shielding wires, and the electromagnetic shielding performance is reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the following will briefly introduce the drawings required to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present utility model, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0029] Figure 1 It is a schematic structural diagram of an application scenario of the electromagnetic shielding wire provided by the embodiment of the present utility model; [[ID=X]]

[0030] Figure 2 It is another schematic structural diagram of an application scenario of the electromagnetic shielding wire provided by the embodiment of the present utility model;

[0031] Figure 3 It is a schematic diagram of the scenario of the ball burning step of the electromagnetic shielding wire provided by the embodiment of the present utility model;

[0032] Figure 4 It is a schematic diagram of the scenario of the bending step of the electromagnetic shielding wire provided by the embodiment of the present utility model;

[0033] Figure 5 It is a schematic diagram of the scenario of the press bending step of the electromagnetic shielding wire provided by the embodiment of the present utility model;

[0034] Figure 6 It is a schematic diagram of the scenario of the wire pulling step of the electromagnetic shielding wire provided by the embodiment of the present utility model;

[0035] Figure 7 It is a schematic diagram of an electromagnetic shielding structure provided by the embodiment of the present utility model.

[0036] Icons: 100 - Electromagnetic shielding wire; 110 - First end; 120 - Main body; 130 - Second end; 121 - First bending section; 122 - Second bending section; 123 - First arc section; 124 - Second arc section; 125 - Third arc section; 200 - Electromagnetic shielding structure; 210 - Substrate; 211 - Metal pad; 212 - Ground wiring layer; 213 - Chip; 215 - Component; 220 - Metal wire; 230 - Bonding head; 240 - Solder ball; 250 - Plastic package; 260 - Shielding layer. Detailed implementation manners

[0037] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some but not all of the embodiments of the present utility model. The components of the embodiments of the present utility model usually described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0038] Therefore, the following detailed description of the embodiments of the present utility model provided in the accompanying drawings is not intended to limit the scope of the claimed present utility model, but merely represents selected embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts fall within the scope of protection of the present utility model.

[0039] It should be noted that: Similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0040] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the present utility model is usually placed during use. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model. In addition, the terms "first", "second", "third", etc. are only used for descriptive distinction and cannot be understood as indicating or implying relative importance.

[0041] In addition, terms such as "horizontal" and "vertical" do not mean that the components are required to be absolutely horizontal or hanging, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0042] It should also be noted that, in the description of this utility model, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0043] The existing cage-like shielding structure is to wire in the substrate and form ground pads on the surface of the substrate. The ground pads are located around the chips or components that need to be shielded. Vertical metal wires are laid on the ground pads. The vertical metal wires surround the chips or components that need to be shielded, thereby forming a cage-like shielding structure.

[0044] The inventors have found that the existing vertical metal wires are easily deformed by molding during the subsequent plastic packaging process, and the thermal expansion coefficients of the vertical metal wires and the plastic packaging body are quite different, which easily leads to structural delamination and affects the packaging reliability.

[0045] To overcome at least one technical deficiency in the prior art, this embodiment provides an electromagnetic shielding wire that increases the contact area between the electromagnetic shielding wire and the plastic package, improves the bonding strength between the shielding wire and the plastic package, prevents structural delamination, and improves packaging reliability. This prevents deformation or breakage of the electromagnetic shielding wire due to molding, ensures uniform spacing between adjacent electromagnetic shielding wires, and ensures reliable electromagnetic shielding performance.

[0046] Please refer to Figure 1 This embodiment provides an electromagnetic shielding wire 100, including a first end portion 110, a main body portion 120, and a second end portion 130. The first end portion 110 is used to connect to the metal pad 211 on the substrate 210. The main body portion 120 is connected to the first end portion 110, and the main body portion 120 is provided with one or more bending sections. The maximum offset of the center line of each bending section relative to the center of the first end portion 110 is 1um to 2mm. The second end portion 130 is provided at one end of the main body portion 120 away from the first end portion 110. The offset between the center of the first end portion 110 and the center of the second end portion 130 in the X direction is 1um to 2mm, and the offset in the Y direction is 1um to 2mm. The X direction is perpendicular to the Y direction.

[0047] Since a plurality of bending segments are provided on the main body portion 120, the contact area between the electromagnetic shielding wire 100 and the plastic encapsulation body 250 can be increased, which helps to improve the bonding force between the shielding wire and the plastic encapsulation body 250, prevent the occurrence of structural delamination, and improve the packaging reliability. In addition, since a plurality of bending segments are provided on the main body portion 120, the stress points of the main body portion 120 can be changed, the load-bearing capacity of the main body portion 120 can be improved, the bending deformation or fracture of the electromagnetic shielding wire 100 caused by molding can be alleviated, the distance between adjacent electromagnetic shielding wires 100 can be ensured to be uniform, and the shielding reliability can be improved.

[0048] It can be understood that the maximum offset of the center line of each bending segment relative to the center of the first end portion 110 is 1 μm to 2 mm. If the offset is too large, the adjacent electromagnetic shielding wires 100 will come into contact or the distance between them will be uneven during subsequent plastic encapsulation and grinding processes, resulting in crosstalk and affecting the electromagnetic shielding effect. Therefore, the maximum offset of the center line of each bending segment relative to the center of the first end portion 110 does not exceed 2 mm. The center line of the bending segment here can be understood as along the central axis of the main body portion 120.

[0049] Such as Figure 1 shown in the figure, the bending segment includes a first bending segment 121 and a second bending segment 122. The maximum offset of the central axis of the first bending segment 121 relative to the center of the first end portion 110 is D1, and the maximum offset of the central axis of the second bending segment 122 relative to the center of the first end portion 110 is D2. D1 and D2 are each less than 2 mm.

[0050] Optionally, the offset between the center of the first end portion 110 and the center of the second end portion 130 in the X direction is 1 μm to 2 mm, that is, the maximum offset does not exceed 2 mm. Preferably, the maximum offset does not exceed 1 mm. The offset between the center of the first end portion 110 and the center of the second end portion 130 in the Y direction is 1 μm to 2 mm, that is, the maximum offset does not exceed 2 mm. Preferably, the maximum offset does not exceed 1 mm. In this embodiment, the X direction and the Y direction are perpendicular to each other.

[0051] Optionally, the distance between the first end portion 110 and the second end portion 130 is 100 μm to 2 mm. It can be understood that the height of the electromagnetic shielding wire 100 is approximately H1, and H1 is 100 μm to 2 mm. The aspect ratio of the main body portion 120 is approximately 10:1 to 100:1.

[0052] Optionally, the angle A between the tangent direction of the second end portion 130 and the vertical direction is 0.5 degrees to 60 degrees. For example, it can be 1 degree, 2 degrees, 5 degrees, 10 degrees, or any value within 0.5 degrees to 60 degrees.

[0053] Optionally, the turning angle B of each bending section is 10° to 150°. For example, it can be 10 degrees, 20 degrees, 30 degrees, 40 degrees or any value between 10 degrees and 150 degrees.

[0054] Optionally, the bending section includes an arc section and / or a broken line section. Only arc sections may be provided in the main body 120. Or, only broken line sections may be provided in the main body 120. Or, both arc sections and broken line sections may be provided in the main body 120. No specific limitation is made here.

[0055] Optionally, as Figure 2 , the bending section includes a first arc section 123, a second arc section 124, and a third arc section 125 connected in sequence. The first arc section 123 is connected to the first end 110, and the third arc section 125 is connected to the second end 130. The bending directions of the first arc section 123 and the second arc section 124 are opposite, and the bending directions of the first arc section 123 and the third arc section 125 are the same. Optionally, the radian of the third arc section 125 is smaller than the radian of the first arc section 123.

[0056] Of course, in some other embodiments, the number of arc sections may be one, two, three, four, five or more. The number of broken line sections may be one, two, three, four, five or more. The broken line sections and the arc sections may be connected alternately or in sequence, and no specific limitation is made here. The cross-sectional shapes of the broken line sections and the arc sections may be circular, elliptical, triangular, quadrilateral, pentagonal, hexagonal or other polygons.

[0057] Optionally, the first end 110, the main body 120 and the second end 130 are integrally formed.

[0058] In this embodiment, the formation method of the electromagnetic shielding wire 100 is generally as follows:

[0059] Combined with Figures 3 to 6 , the formation of the electromagnetic shielding wire 100 mainly includes four steps, namely ball burning, bending, press bending and wire drawing.

[0060] Step 1: Ball burning. Using mechanical grinding ultrasonic vibration on the substrate 210, the metal wire 220 passes through the capillary and is led out from the capillary head 230, and the capillary head 230 hits the metal wire 220 on the metal pad 211 of the substrate 210 to ablate and form a solder ball 240.

[0061] Step 2: Bending. Using the splitter head 230 again, the wire 220 connected to the solder ball 240 is lifted along the first direction (Z) to form a wire arc. After the wire arc reaches a certain height, it is bent along the second direction (X) and extended to a certain length, thereby reducing the wire arc's ductility. Optionally, the first direction is substantially vertical, and the second direction is substantially horizontal. The angle between the first and second directions is approximately 60 to 120 degrees.

[0062] Step 3: Pressing and bending: Use the splitter head 230 to press the arc end in the second direction downward to a position close to the substrate 210, roughly flush with the metal pad 211 on the substrate 210, and apply force to the arc end close to the substrate 210 to cause a crack.

[0063] Step 4: Pull the wire. Use the splitter head 230 to pull the end of the wire arc straight up, causing it to move upward and forming a breakpoint where the crack appears. This will form a metal wire with a bent section.

[0064] It can be understood that if multiple bending steps are performed in the bending step, followed by press bending and wire pulling, the electromagnetic shielding wire 100 finally formed will have multiple bending sections. The specific number of bending times can be set according to actual needs and is not specifically limited here.

[0065] Combine Figure 7 The embodiment of the present invention also provides an electromagnetic shielding structure 200, comprising a substrate 210, a chip 213, a plastic package 250, a shielding layer 260 and the electromagnetic shielding wire 100 as described above. The chip 213 is provided on the substrate 210, and the chip 213 and the substrate 210 are electrically connected. A metal pad 211 is provided on the substrate 210, and the electromagnetic shielding wire 100 is connected to the metal pad 211, and the electromagnetic shielding wire 100 is located on the periphery of the chip 213. The plastic package 250 wraps the chip 213 and the electromagnetic shielding wire 100, and the electromagnetic shielding wire 100 is exposed from the surface of the plastic package 250. The shielding layer 260 is provided on the surface of the plastic package 250 and is electrically connected to the electromagnetic shielding wire 100. The electromagnetic shielding structure 200 can achieve electromagnetic shielding of the chip 213 and improve the shielding performance.

[0066] Optionally, other components 215 are further provided on the substrate 210. The components 215 are electrically connected to the substrate 210 and are located outside the area surrounded by the electromagnetic shielding wire 100. The components 215 include, but are not limited to, one or more of chips, capacitors, resistors, and inductors.

[0067] Optionally, a ground wiring layer 212 is provided within the substrate 210, and the metal pads 211 are electrically connected to the ground wiring layer 212. Alternatively, the ground wiring layer 212 extends to the scribe line, is exposed from the sidewall of the substrate 210, and is electrically connected to the shielding layer 260. Alternatively, the ground wiring layer 212 is both exposed from the sidewall and electrically connected to the metal pads 211 on the surface of the substrate 210.

[0068] Optionally, the projections of multiple electromagnetic shielding wires 100 on the substrate 210 are roughly circular, elliptical, triangular, quadrilateral, pentagonal or any polygon, or Z-shaped, H-shaped, L-shaped, U-shaped, W-shaped, etc., or can be a combination of multiple shapes, or designed into an irregular arbitrary shape according to actual needs, which is not specifically limited here.

[0069] It should be noted that after chip 213 is mounted on substrate 210, the aforementioned electromagnetic shielding wire 100 is applied to the periphery of chip 213, and then plastic-encapsulated to form a plastic encapsulation body 250. Plastic encapsulation body 250 is then ground to expose the electromagnetic shielding wire 100 from the surface of plastic encapsulation body 250. This grinding step also removes a portion of the top of the electromagnetic shielding wire 100 to maintain the smoothness of the surface of plastic encapsulation body 250. Finally, a conductive shielding layer 260 is sputtered onto the surface of plastic encapsulation body 250.

[0070] In summary, the electromagnetic shielding wire 100 and the electromagnetic shielding structure 200 provided by the embodiments of the present invention have the following beneficial effects, including:

[0071] The electromagnetic shielding wire 100 provided in this embodiment of the utility model has multiple bent sections on the main body 120, which can increase the contact area between the electromagnetic shielding wire 100 and the plastic encapsulation body 250, thereby helping to improve the bonding strength between the shielding wire and the plastic encapsulation body 250, prevent structural delamination, and enhance packaging reliability. Furthermore, the multiple bent sections on the main body 120 can change the stress points of the main body 120, improve the load-bearing capacity of the main body 120, mitigate deformation or fracture of the electromagnetic shielding wire 100 caused by molding, ensure uniform spacing between the multiple electromagnetic shielding wires 100, and improve the reliability of electromagnetic shielding.

[0072] The electromagnetic shielding structure 200 provided by the present embodiment of the utility model, including the electromagnetic shielding wire 100 described above, is advantageously used to increase the contact area between the electromagnetic shielding wire 100 and the plastic package 250, thereby improving the bonding strength between the shielding wire and the plastic package 250, preventing structural delamination, and improving packaging reliability. This prevents deformation or breakage of the electromagnetic shielding wire 100 due to molding, ensures uniform spacing between adjacent electromagnetic shielding wires 100, and ensures reliable electromagnetic shielding performance.

[0073] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. For those skilled in the art, various modifications and variations can be made to the present utility model. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. An electromagnetic shielding wire, characterized in that, Comprising: A first end portion for connecting to a metal pad on a substrate; A main body portion connected to the first end portion, the main body portion being provided with one or more bending segments; the maximum offset of the center line of each bending segment relative to the center of the first end portion is 1 μm to 2 mm; A second end portion provided at one end of the main body portion away from the first end portion; The offset between the center of the first end portion and the center of the second end portion is 1 μm to 2 mm in the X direction and 1 μm to 2 mm in the Y direction; the X direction is perpendicular to the Y direction.

2. The electromagnetic shielding wire according to claim 1, characterized in that, The distance between the first end portion and the second end portion is 100 μm to 2 mm.

3. The electromagnetic shielding wire according to claim 1, characterized in that, The turning angle of each bending segment is 10° to 150°.

4. The electromagnetic shielding wire according to claim 1, wherein The bending segment includes an arc segment and / or a straight segment.

5. The electromagnetic shielding wire according to claim 1, characterized in that, The bending segment includes a first arc segment, a second arc segment, and a third arc segment connected in sequence; the bending directions of the first arc segment and the second arc segment are opposite, and the bending directions of the first arc segment and the third arc segment are the same.

6. The electromagnetic shielding wire according to claim 5, characterized in that, The radian of the third arc segment is smaller than the radian of the first arc segment.

7. The electromagnetic shielding wire according to claim 1, wherein The included angle between the tangent direction of the second end portion and the vertical direction is 0.5 degrees to 60 degrees.

8. The electromagnetic shielding wire according to claim 1, wherein The first end portion, the main body portion, and the second end portion are integrally formed.

9. An electromagnetic shielding structure, characterized in that, Comprising a substrate, a chip, a plastic package, a shielding layer, and an electromagnetic shielding wire according to any one of claims 1 to 8, the chip being provided on the substrate and the chip being electrically connected to the substrate; A metal pad is provided on the substrate, the electromagnetic shielding wire is connected to the metal pad, and the electromagnetic shielding wire is located on the outer periphery of the chip; The plastic package wraps the chip and the electromagnetic shielding wire, and the electromagnetic shielding wire is exposed from the surface of the plastic package; The shielding layer is provided on the surface of the plastic package and is electrically connected to the electromagnetic shielding wire.

10. The electromagnetic shielding structure according to claim 9, wherein, A ground wiring layer is provided in the substrate, and the metal pad is electrically connected to the ground wiring layer; And / or, the ground wiring layer extends to the dicing street, is exposed from the side wall of the substrate, and is electrically connected to the shielding layer.

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