Lead frame
By setting a recessed structure at the connection between the connecting ribs and pins of the lead frame, the short circuit risk caused by shortening of the pin spacing is solved and the yield of semiconductor products is improved.
Patent Information
- Application Number
- CN202422292014.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-19
- Publication Date
- 2025-08-22
- Estimated Expiration
- 2034-09-19
AI Technical Summary
The existing lead frames form rounded corners near the connecting ribs, resulting in a shortening of adjacent pin spacing, increasing the risk of short circuits in the cut semiconductor product circuits.
At the connection ribs and pins of the lead frame, the recesses are set to recessed toward the inner part of the connecting ribs along the pin extension direction to ensure the spacing between adjacent pins and reduce the risk of short circuit.
By setting the recess, the yield of semiconductor products is improved, the risk of short circuits of adjacent pins is reduced, and the reliability of the product is improved.
Smart Images
Figure CN223260597U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of semiconductor technology, and in particular to a lead frame. Background Art
[0002] The semiconductor product packaging process often uses a lead frame to connect the chip to lead out the chip's pads. The lead frame generally includes pins and connecting ribs. Since the connecting ribs will be cut off after packaging, the setting of the pins and connecting ribs directly affects the performance of the semiconductor product after cutting. Figure 1 As shown, in the related art, the lead frame 100' includes connected pins 10' and connecting ribs 20'. Due to the manufacturing process and other reasons, the prepared lead frame 100' forms a connection between the pins 10' and the connecting ribs 20'. Figure 1 As shown, the fillet 30 ′ shortens the distance between two adjacent pins 10 ′ near the connecting rib 20 ′, which brings a risk of short circuit to the pins 10 ′ after cutting. Summary of the Invention
[0003] An embodiment of the present application provides a lead frame, which includes a plurality of lead frame units, each of which includes a connecting rib located on the periphery and a plurality of pins connected to the inner side of the connecting rib; wherein, the connection between the connecting rib and at least some of the pins is provided with a recessed portion that is recessed toward the interior of the connecting rib along the extension direction of the corresponding pin.
[0004] In some embodiments, each of the pins has a pin body and a connecting portion connecting the pin body and the connecting rib, the connecting portion has two side edges located on opposite sides of the pin extension direction, and a recess is provided at the connection between the connecting rib and at least part of the two side edges of the pin.
[0005] In some embodiments, the recess is located on a side of the corresponding side facing away from the corresponding pin.
[0006] In some embodiments, at least a portion of the side edges of the pins transition smoothly to the wall of the corresponding recess.
[0007] In some embodiments, the wall surface of the recess is a smooth curved surface.
[0008] In some embodiments, a cross-section of a wall surface of the recess in a thickness direction of the lead frame is in the shape of a circular arc or an elliptical arc.
[0009] In some embodiments, when the cross-section of the wall surface of the recess in the thickness direction of the lead frame is in an arc shape, the cross-section of the wall surface of the recess in the thickness direction of the lead frame is in a semicircular shape.
[0010] In some embodiments, the inwardly recessed depth of the concave portion is 0.0625-0.25 times the thickness of the lead frame.
[0011] In some embodiments, the inward depression depth of the recess is less than 1 / 3 of the width of the connecting rib where the recess is located.
[0012] In some embodiments, a plurality of the lead frame units are arranged in at least one array unit, and the connecting ribs include a first connecting rib connecting the pins of two adjacent lead frame units in the same array unit, and a second connecting rib located at the outer edge of each of the array units, and at least one of the first connecting rib and the second connecting rib is provided with a recess at the connection with the corresponding pin.
[0013] The main technical effects achieved by the embodiments of the present application are:
[0014] The lead frame provided in the embodiment of the present application is configured to have a recessed portion at the connection between the connecting rib and at least part of the pins, which is recessed toward the interior of the connecting rib along the extension direction of the corresponding pin. This can better ensure the spacing between adjacent pins, reduce the risk of short circuit between two adjacent pins when the connecting rib of the lead frame is cut, and improve the yield of semiconductor products. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 This is a partial structural diagram of a lead frame in the related art;
[0016] Figure 2 1 is a schematic structural diagram of a lead frame provided by an exemplary embodiment of the present application;
[0017] Figure 3 yes Figure 2 An enlarged schematic diagram of point A is shown;
[0018] Figure 4 yes Figure 3 An enlarged schematic diagram of point B is shown. DETAILED DESCRIPTION
[0019] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.
[0020] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. As used in this application and the appended claims, the singular forms "a," "an," "the," and "the" are intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.
[0021] The following is combined with Figures 2 to 4 , some embodiments of the lead frame of the present application are described in detail. In the absence of conflict, the features of the following embodiments can be combined with each other.
[0022] Please refer to Figure 2 , and when necessary, combine Figure 3 and Figure 4 As shown, the present application provides a lead frame 100. The lead frame 100 includes a plurality of lead frame units 101, each of which includes a connecting rib 20 located on the periphery and a plurality of pins 10 connected to the inner side of the connecting rib 20; wherein, the connection between the connecting rib 20 and at least some of the pins 10 is provided with a recess 201 that is recessed into the interior of the connecting rib 20 along the extension direction of the corresponding pin 10.
[0023] Each lead frame unit 101 has a circumferentially arranged connection rib 20. The inner side of the connection rib 20 can be understood as the space enclosed by the circumferentially arranged connection rib 20.
[0024] The indentation toward the interior of the connecting rib 20 may be understood as indentation toward the middle of the connecting rib 20 , that is, indentation from the edge of the connecting rib 20 close to the corresponding pin 10 toward the side away from the corresponding pin 10 .
[0025] The lead frame 100 is configured to have a recessed portion at the connection between the connecting rib 20 and at least a portion of the pins 10, which is recessed toward the interior of the connecting rib 20 along the extension direction of the corresponding pin 10. This can better ensure the spacing between adjacent pins, reduce the risk of short circuit between two adjacent pins when the connecting rib of the lead frame is cut, and improve the yield of semiconductor products.
[0026] like Figure 2 As shown, in some embodiments, the plurality of lead frame units 101 are arranged in a plurality of array units 1, and the connecting ribs 20 include first connecting ribs 2001 connecting the leads 10 of two adjacent lead frame units 101 in the same array unit 1. At least some of the leads 10 of each lead frame unit 101 may be connected to corresponding first connecting ribs 2001.
[0027] The first connecting rib 2001 can be understood as the integration of the connecting ribs at the connection point of two adjacent lead frame units 101.
[0028] In some embodiments, a recess 201 is provided at a connection between the first connecting rib 2001 and the pin 10 connected to the first connecting rib 2001 .
[0029] like Figure 4 As shown, the pin 1001 connected to the first connecting rib 2001 extends along the first direction Y. The portion of the first connecting rib 2001 to which the pin 1001 is connected extends along the second direction X.
[0030] Correspondingly, the recess 201 provided at the connection between the first connecting rib 2001 and the pin 1001 connected to the first connecting rib 2001 is recessed from the edge of the first connecting rib 2001 along the first direction Y toward the interior of the first connecting rib 2001 .
[0031] like Figure 4 As shown, the pin 1002 connected to the first connecting rib 2001 extends along the second direction X. The portion of the first connecting rib 2001 to which the pin 1002 is connected extends along the first direction Y.
[0032] Correspondingly, the recess 201 provided at the connection between the first connecting rib 2001 and the pin 1002 connected to the first connecting rib 2001 is recessed from the edge of the first connecting rib 2001 along the second direction X toward the interior of the first connecting rib 2001 .
[0033] It is understandable that the recess 201 may be provided at the connection point between the first connecting rib 2001 and each pin 10 to minimize the risk of short circuit between two adjacent pins.
[0034] In some embodiments, the lead frame 100 further includes a second connecting rib 2002 located at an outer edge of each of the array units 1 .
[0035] The second connecting rib 2002 is connected to a corresponding portion of the first connecting rib 2001 of the lead frame unit 101 in which it is located. Some pins in the lead frame unit 101 in which the second connecting rib 2002 is located may be connected to the second connecting rib 2002.
[0036] In some embodiments, a recess 201 is provided at a connection point between at least one of the second connecting ribs 2002 and the corresponding pin 10 .
[0037] Among them, a portion of the pins connected to the second connecting rib 2002 extends along the first direction Y. The second connecting rib 2002 connected to the portion of the pins extends along the second direction X, for example Figure 2Part of the second connecting rib 20021 is shown.
[0038] Correspondingly, the recess 201 provided at the connection between the portion of the second connecting rib 20021 and the pin connected to the portion of the second connecting rib 20021 is recessed from the edge of the portion of the second connecting rib 20021 along the first direction Y toward the interior of the portion of the second connecting rib 20021 .
[0039] Another portion of the pins connected to the second connecting rib 2002 extends along the second direction X. The portion of the second connecting rib 2002 to which the pins are connected extends along the first direction Y, for example Figure 2 Part of the second connecting rib 20022 is shown.
[0040] Correspondingly, the recess 201 provided at the connection between the portion of the second connecting rib 20022 and the pin connected to the portion of the second connecting rib 20022 is recessed from the edge of the portion of the second connecting rib 20022 along the second direction X toward the interior of the second connecting rib 20022 .
[0041] It is understandable that the connection points between the second connecting rib 2002 and all the pins 10 connected thereto may be provided with recesses 201 to minimize the risk of short circuit between two adjacent pins.
[0042] It should be noted that in some other embodiments, recesses may be provided only on the first connecting rib at the connection with the corresponding pin, or only on the second connecting rib at the connection with the corresponding pin. In addition, recesses may be provided on each connecting rib at the connection between the connecting rib and some of the pins.
[0043] In some embodiments, each of the pins 10 has a pin body 11 and a connecting portion 12 connecting the pin body 11 and the connecting rib 20, and the connecting portion 12 has two sides located on opposite sides of the extending direction of the pin 10. Figure 4 The first side 121 and the second side 122 are shown. A recess 201 is provided at the connection between the connecting rib 20 and at least part of the two side edges of the pin 10.
[0044] In some embodiments, the recess 201 is located on a side of the corresponding side away from the corresponding pin 10 .
[0045] like Figure 4As shown, the recess 2012 provided at the connection between the first side 121 and the connecting rib 20 is entirely located on the side of the first side 121 away from the pin 10, that is, the recess 2012 and the connecting portion 12 of the pin 10 are staggered in a direction perpendicular to the extension direction of the pin 10. This can reduce the impact on the width of the pin 10 and ensure the structure of the pin. The recess 2011 provided at the connection between the second side 122 and the connecting rib 20 is entirely located on the side of the second side 122 away from the pin 10. That is, the recess 2011 and the connecting portion 12 of the pin 10 are staggered in a direction perpendicular to the extension direction of the pin 10. This can reduce the impact on the width of the pin 10 and ensure the structure of the pin.
[0046] In some embodiments, two side edges of each pin 10 smoothly transition to the wall of the recess 201 .
[0047] like Figure 4 As shown, the first side 121 and the wall surface of the concave portion 2012 at the connection point thereof are smoothly transitioned. The second side 122 and the wall surface of the concave portion 2011 provided at the connection point of the connecting rib 20 are smoothly transitioned.
[0048] It should be noted that in some other embodiments, the lead frame may be configured such that the side edges of some pins transition smoothly with the wall of the corresponding recess, or such that only one of the two side edges of at least some pins transitions smoothly with the wall of the corresponding recess.
[0049] In some embodiments, the wall surface of the recess 201 is a smooth curved surface to prevent stress concentration at non-smooth portions of the lead frame and improve the structural strength of the lead frame.
[0050] In some embodiments, the cross-section of the wall surface of the recess 201 in the thickness direction of the lead frame 100 is in the shape of a circular arc, an elliptical arc, or other regular or irregular smooth curved surfaces.
[0051] It is understood that the thickness direction is as follows Figure 4 The direction shown is perpendicular to the paper.
[0052] Of course, in some other embodiments, the recess may also be configured such that a portion of the wall surface is not smooth, such as a straight corner.
[0053] In some embodiments, when the cross-section of the wall surface of the recess 201 in the thickness direction of the lead frame 100 is in an arc shape, the cross-section of the wall surface of the recess 201 in the thickness direction of the lead frame 100 is in a semicircular shape.
[0054] Accordingly, in some embodiments, a tangent line of the semicircular recess at the connection point between the connecting rib and the side of the pin is consistent with the extension direction of the corresponding pin.
[0055] for example Figure 4 As shown, the lead 1001 extends along the first direction Y, and the wall surface of the recess 2011 has a semicircular cross-section along the thickness direction of the lead frame 100. A tangent line r of the semicircular recess 2011 at the junction of the connecting rib 20 and the side 122 of the lead 1001 extends along the first direction Y. That is, the tangent line r is consistent with the extension direction of the corresponding lead 1001.
[0056] In some embodiments, the inwardly recessed depth of the recess 201 is 0.0625-0.25 times the thickness of the lead frame.
[0057] like Figure 4 As shown, the inwardly recessed depth h of the concave portion 201 is 0.0625-0.25 times the thickness of the lead frame 100 .
[0058] For example, when the thickness of the lead frame 100 is 0.2 mm, the depth h of the recess 201 is 0.0125 mm-0.05 mm.
[0059] For example, when the thickness of the lead frame 100 is 0.1 mm, the depth h of the recess 201 is 0.00625 mm-0.025 mm.
[0060] For another example, when the thickness of the lead frame 100 is 0.25 mm, the depth h of the recess 201 is 0.015625 mm-0.0625 mm.
[0061] In some embodiments, the inward depression depth of the recess 201 is less than 1 / 3 of the width of the connecting rib where the recess 201 is located, so as to ensure the strength of the connecting rib.
[0062] For example, Figure 4 As shown, the inwardly recessed depth h of the recess 201 is less than 1 / 3 of the width W of the connecting rib 20 where the recess 201 is located. The width W of this portion of the connecting rib 20 may be the dimension along the first direction Y.
[0063] It can be understood that, in some embodiments, all recesses 201 provided on the connecting ribs 20 of the same lead frame 100 may have the same shape and size.
[0064] In other embodiments, the recesses provided on the connecting ribs of the same lead frame may also have different shapes and sizes.
[0065] In certain embodiments, those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the disclosure disclosed herein. This application is intended to encompass any variations, uses, or adaptations of the present application, which follow the general principles of the present application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the claims below.
[0066] It should be understood that the present application is not limited to the exact structures described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.
Claims
1. A lead frame, characterized in that: The lead frame includes a plurality of lead frame units, each of which includes a connecting rib located on the periphery and a plurality of pins connected to the inner side of the connecting rib; wherein, the connection between the connecting rib and at least some of the pins is provided with a recessed portion recessed toward the interior of the connecting rib along the extension direction of the corresponding pin.
2. The lead frame according to claim 1, wherein Each of the pins has a pin body and a connecting portion connecting the pin body and the connecting rib. The connecting portion has two side edges located on opposite sides of the pin extension direction. The connecting rib is provided with a recess at the connection between the two side edges of at least part of the pin.
3. The lead frame according to claim 2, wherein: The recess is located on a side of the corresponding side away from the corresponding pin.
4. The lead frame according to claim 2, wherein: At least part of the side edges of the pins transition smoothly with the wall surface of the corresponding recess.
5. The lead frame according to claim 1, wherein The wall surface of the recess is a smooth curved surface.
6. The lead frame according to claim 5, wherein: A cross section of a wall surface of the recessed portion in a thickness direction of the lead frame is in an arc shape or an elliptical arc shape.
7. The lead frame according to claim 6, wherein: When the cross section of the wall surface of the recessed portion in the thickness direction of the lead frame is in an arc shape, the cross section of the wall surface of the recessed portion in the thickness direction of the lead frame is in a semicircular shape.
8. The lead frame according to any one of claims 1 to 7, wherein: The inwardly recessed depth of the concave portion is 0.0625-0.25 times the thickness of the lead frame.
9. The lead frame according to any one of claims 1 to 7, wherein: The inwardly recessed depth of the recess is less than 1 / 3 of the width of the connecting rib where the recess is located.
10. The lead frame according to claim 1, wherein The plurality of lead frame units are arranged in at least one array unit, and the connecting ribs include a first connecting rib connecting the pins of two adjacent lead frame units in the same array unit, and a second connecting rib located at the outer edge of each of the array units, and at least one of the first connecting rib and the second connecting rib is provided with a recess at the connection with the corresponding pin.