Lead frame

Abstract

The lead frame provided by the utility model comprises carrier units, a connecting unit and a pin unit, the two carrier units are connected through the connecting unit, and the pin unit is arranged at one end, far away from the connecting unit, of each carrier unit; the connecting unit comprises a first connecting part and heat dissipation parts, the heat dissipation parts are symmetrically arranged on the two sides of the first connecting part and are parallel to the direction of the first center line, and the two ends of the first connecting part are connected with the carrier units on the two sides respectively. According to the lead frame provided by the invention, the connecting unit is provided with the first connecting part and the heat dissipation parts, and the heat dissipation parts are arranged at the two ends of the first connecting part, that is, the middle part of the connecting unit is directly connected with the carrier units at the two sides, so that the transmission path between the two carrier units is shortened, and the transmission rate of the lead frame is improved; moreover, the two sides of the first connecting part are also provided with the heat dissipation parts, so that the connection strength and the transmission effect of the two carrier units are ensured, the heat dissipation performance can be ensured, and a relatively good heat dissipation effect is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor packaging, in particular to a lead frame. BACKGROUND

[0002] Chip packaging is a technology of packaging integrated circuits with insulating plastic or ceramic materials, which not only plays a role of placing, fixing, sealing, protecting chips and enhancing heat dissipation performance, but also is a bridge between the internal world of the chip and the external circuit.

[0003] The lead frame in the prior art is mostly double-row, and a connecting sheet is arranged between the two carrier units to connect them. In order to ensure heat dissipation, a heat dissipation hole is mostly arranged on the connecting sheet. However, most of the heat dissipation holes are mouth-shaped, so as to form a back-shaped connecting channel on the connecting sheet. Such a structure increases the transmission path between the two carrier units, and the signal transmission speed is slow, and the information processing efficiency is also reduced accordingly.

[0004] Therefore, the lead frame in the prior art has further improvement space. CONTENT OF THE INVENTION

[0005] Therefore, in view of the technical problem of slow transmission between the carriers of the lead frame in the prior art, the present application provides a lead frame, which is provided with a first connecting part on the connecting unit, and a heat dissipation hole is arranged at both ends of the first connecting part, thereby reducing the transmission path between the two carriers and improving the transmission rate of the lead frame.

[0006] The present application provides a lead frame, which comprises a carrier unit, a connecting unit and a pin unit, two carrier units are connected through the connecting unit, and the pin unit is arranged at one end of the carrier unit away from the connecting unit.

[0007] The connecting unit comprises a first connecting part and a heat dissipation part, the heat dissipation part is symmetrically arranged on both sides of the first connecting part, and the first connecting part is connected with the carrier units on both sides in parallel to the direction of the first center line.

[0008] Compared with the prior art, the present application provides a lead frame, which is provided with a first connecting part and a heat dissipation part in the connecting unit, and the heat dissipation part is arranged at both ends of the first connecting part, that is, the middle part of the connecting unit is directly connected with the carrier units on both sides, thereby shortening the transmission path between the two carrier units and improving the transmission rate of the lead frame. In addition, the heat dissipation part is arranged on both sides of the first connecting part, so that the connection strength and transmission effect of the two carrier units are ensured, and the heat dissipation performance is also ensured, thereby achieving good heat dissipation effect.

[0009] Preferably, the first connecting part comprises a first connecting piece and a second connecting piece, the first connecting piece and the second connecting piece are rectangular structures;

[0010] The second connecting piece is arranged at both ends of the first connecting piece, and the end of the second connecting piece away from the first connecting piece is connected with the carrier unit.

[0011] Preferably, in the direction parallel to the first center line, the length of the second connecting piece is greater than the length of the first connecting piece.

[0012] Preferably, in the direction parallel to the first center line, the length of the first connecting piece is L1, and the length of the second connecting piece is L2, wherein L1:L2=1 / 3~2 / 5.

[0013] Preferably, the length of the heat dissipation part is L3, and L1:L3=1 / 3~2 / 5.

[0014] Preferably, the end of the second connecting piece close to the carrier unit is provided with a heat dissipation opening, and the center line of the heat dissipation opening is on the same straight line as the second center line.

[0015] Preferably, in the direction parallel to the second center line, the length of the heat dissipation opening is L4, and the length of the second connecting piece is L5, and L4:L5=1 / 3~2 / 5.

[0016] Preferably, the heat dissipation part comprises a first heat dissipation hole and a second heat dissipation hole, and the first heat dissipation hole and the second heat dissipation hole are arranged in parallel to the second center line.

[0017] Preferably, the first heat dissipation hole and the second heat dissipation hole have the same structure, and the first heat dissipation hole and the second heat dissipation hole are symmetrically arranged along the first center line.

[0018] Preferably, the heat dissipation part is provided with an enlarged hole, and the enlarged hole is arranged at the end of the heat dissipation part close to the first connecting part.

[0019] The enlarged hole extends in the direction parallel to the second center line and towards the carrier unit.

[0020] Preferably, in the direction parallel to the second center line, the length of the enlarged hole is L6, and the length of the first heat dissipation hole is L7, wherein L6:L7=1 / 3~2 / 5.

[0021] In the direction parallel to the first center line, the length of the enlarged hole is L8, and the length of the first heat dissipation hole is L9, wherein L8:L9=1 / 20~1 / 10.

[0022] Preferably, the side of the enlarged hole away from the first connecting part is an oblique side, and in the direction parallel to the first center line, the included angle between the oblique side and the side of the heat dissipation part is an acute angle.

[0023] Preferably, the connecting unit further comprises a second connecting part, the middle part of the second connecting part is connected with the end part of the heat dissipation part away from the first connecting part, and the two end parts of the second connecting part are connected with the pin unit;

[0024] The lead frame comprises a first carrier group and a second carrier group, and the first carrier group and the second carrier group are connected through the heat dissipation part in the direction parallel to the first center line;

[0025] The end part of the heat dissipation part away from the first connecting part is provided with a positioning hole.

[0026] Preferably, the pin unit comprises a pin part and a soldering leg part, the soldering leg part is connected with the pin part, and the pin part is connected with the second connecting part;

[0027] The second connecting part is provided with a bending piece.

[0028] The lead frame provided by the application has at least the following technical effects:

[0029] 1. By arranging the first connecting part, the heat dissipation part is arranged on the two sides of the first connecting part, so that the transmission path between the two carrier units is shortened and the transmission efficiency is improved while the heat dissipation effect is ensured;

[0030] 2. By arranging the hole expansion on the heat dissipation part, and arranging the hole expansion on the end part of the heat dissipation part close to the first connecting part, the hole expansion can increase the connection strength between the plastic sealing agent and the first connecting part when the lead frame is packaged, and the plastic sealing effect is improved;

[0031] 3. By arranging the second connecting part, the second connecting part is arranged on the end part of the heat dissipation part away from the first connecting part, and the second connecting part is connected with the pin part, so that the carrier unit is connected with the pin unit through the second connecting part, and the number of pins can be increased. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 is a structural schematic view of the lead frame provided by an embodiment of the application;

[0033] Figure 2 is a side view structural schematic view of the lead frame provided by an embodiment of the application;

[0034] Figure 3 is Figure 1 a partial A enlarged schematic view of

[0035] Figure 4 is Figure 3 a partial B enlarged schematic view of

[0036] Figures: 1, carrier unit; 2, connecting unit; 3, pin unit; 4, positioning hole;

[0037] 11. First carrier group; 12. Second carrier group;

[0038] 21. First connecting part; 22. Second connecting part; 23. Heat dissipation part;

[0039] 211. First connecting piece; 212. Second connecting piece; 221. Bending piece;

[0040] 231. Heat dissipation vent; 232. First heat dissipation hole; 233. Second heat dissipation hole; 234. Enlarged hole; 2341. Bevel;

[0041] 31. Pin portion; 32. Solder foot portion. Detailed Implementation

[0042] To enable those skilled in the art to better understand the technical solutions of this disclosure, the following detailed, clear, and complete description of this disclosure is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this disclosure and are not intended to limit it.

[0043] In the description of this application, the use of "first" and "second" is for the purpose of distinguishing technical features only, and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or the order of the technical features indicated.

[0044] Those skilled in the art should understand that in the disclosure of this application, the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the above terms should not be construed as limitations on this application.

[0045] The present application will now be described in further detail with reference to the accompanying drawings, see below. Figures 1 to 4 illustrate.

[0046] This application provides a lead frame, which is a T2PAK type lead frame, and is a novel lead frame; such as Figure 1 As shown, the lead frame includes two sets of carrier units 1, namely the first carrier group 11 and the second carrier group 12. Each set of carrier units 1 includes two carrier units 1, which are arranged in parallel vertically and in parallel horizontally. That is, each lead frame includes four carrier units 1.

[0047] It should be noted that the two groups of carrier units 1 are arranged side by side in parallel to the first direction, the first center line is parallel to the first direction, and the first direction is parallel to the X axis; the two carrier units 1 in the same group are arranged in parallel to the second direction, the second center line is parallel to the second direction, and the second direction is parallel to the Y axis.

[0048] As shown in Figure 1 , the lead frame includes carrier units 1, connection units 2, and pin units 3, in the same group of carrier units 1, two carrier units 1 are connected by a connection unit 2, and a pin unit 3 is arranged at one end of the carrier unit 1 away from the connection unit 2; wherein, as shown in Figure 1 , Figure 3 , the connection unit 2 includes a first connecting part 21 and a heat dissipation part 23, the first connecting part 21 is connected to the middle part of the carrier unit 1, wherein the first connecting part 21 has a first center line in the first direction, and the first connecting part 21 has a second center line in the second direction; the heat dissipation part 23 is symmetrically arranged on both sides of the first connecting part 21 with the second center line as the axis of symmetry, and the two ends of the first connecting part 21 parallel to the second center line are respectively connected with the carrier units 1 on both sides, that is, the two ends of the first connecting part 21 are directly connected with the carrier units 1, and the first connecting part 21 extends in parallel to the second center line, compared with the existing technology of the character-shaped structure, the first connecting part 21 of the present application shortens the transmission path of the two carrier units 1, and improves the transmission efficiency between the two carrier units 1 in the same group; at the same time, as shown in Figure 3 , the heat dissipation part 23 arranged at both ends of the first connecting part 21 makes the connection unit 2 also have good heat dissipation function.

[0049] As shown in Figure 1 , the first carrier group 11 and the second carrier group 12 are connected by the respective heat dissipation parts 23; and the heat dissipation part 23 is provided with a positioning hole 4, the positioning hole 4 is arranged at the end of the heat dissipation part 23 away from the first connecting part 21, and the heat dissipation parts 23 in the two groups of carrier units 1 are connected to form a circular positioning hole 4.

[0050] Further, as shown in Figure 1 , the connection unit 2 further includes a second connecting part 22, the second connecting part 22 is arranged at one end of the heat dissipation part 23 away from the first connecting part 21, the second connecting part 22 is arranged in parallel to the second direction, the middle part of the second connecting part 22 is connected with the heat dissipation part 23, and the two ends of the second connecting part 22 are connected with the pin units 3 at both ends in parallel to the second direction.

[0051] In the present application, as shown in Figure 1As shown, the application includes four heat dissipation parts 23, the heat dissipation parts 23 at both ends of the first connecting part 21 are the same structure, but are symmetrically arranged along the second center line; the application includes four heat dissipation parts 23, four carrier units 1, two first connecting parts 21 and two second connecting parts 22, wherein the two carrier groups are connected through the heat dissipation parts 23, and the two carrier groups are connected through the pin units 3; in the same carrier group, the two carrier units 1 are connected through the first connecting part 21, and the carrier unit 1 is connected with the pin unit 3 through the second connecting part 22; and the heat dissipation part 23 on one side of the first connecting part 21 is connected with the second connecting part 22, and the heat dissipation part 23 on the other side is connected with the heat dissipation part 23 of the other carrier unit 1.

[0052] Further, as shown in the drawings, Figure 1 As shown, the pin unit 3 includes a pin part 31 and a solder part 32, and the solder part 32 is connected with the pin part 31 in the second direction; the outer end of the pin part 31 is connected with the second connecting part 22 in the first direction; wherein the solder part 32 includes seven solder pins, and the pin part 31 includes at least seven pins; the second connecting part 22 is provided with a bending piece 221 for connecting the pin unit 3 and the carrier unit 1 which are not in the same plane, and the bending piece 221 is arranged on the second connecting part 22, so that the pin part 31 can be arranged in multiple, the solder part 32 can be arranged in multiple, the number of pins is increased, and the demand for multiple pins can be met.

[0053] Based on any of the above embodiments, the first connecting part 21 is further described; as shown, Figure 3 The first connecting part 21 includes a first connecting piece 211 and a second connecting piece 212, and the first connecting piece 211 and the second connecting piece 212 are rectangular structures, wherein the second connecting piece 212 is arranged at both ends of the first connecting piece 211 in the second direction, that is, the carrier unit 1 is connected with the first connecting piece 211 through the second connecting piece 212; wherein the length of the second connecting piece 212 is greater than the length of the first connecting piece 211 in the direction parallel to the first center line, and the length of the second connecting piece 212 is less than the length of the carrier unit 1; as shown, Figure 3 The length of the first connecting piece 211 is L1, the length of the second connecting piece 212 is L2, and the length of the heat dissipation part 23 is L3, wherein L1:L2=1 / 3~2 / 5; L1:L3=1 / 3~2 / 5, the length of the heat dissipation part 23 is longer, the heat dissipation area is larger, and better heat dissipation effect can be provided.

[0054] Preferably, L1:L2=0.38.

[0055] Further, as shown in the drawings, Figure 3As shown, the second connecting sheet 212 is provided with a heat dissipation opening 231 near the end of the carrier unit 1, the heat dissipation opening 231 is a rectangular structure as a whole, the center line of the heat dissipation opening 231 is on the same straight line as the second center line, wherein, parallel to the first direction, the length of the heat dissipation opening 231 is the same as the length of the first connecting sheet 211; parallel to the direction of the second center line, the length of the heat dissipation opening 231 is L4, the length of the second connecting sheet 212 is L5, L4: L5 = 1 / 3 ~ 2 / 5, by such setting, when the second connecting sheet 212 is connected with the carrier unit 1, the corresponding heat dissipation opening 231 is also provided, to avoid overheating when the two are in contact; at the same time, when plastic packaging, the connection strength of the plastic packaging agent and the second connecting sheet 212 and the carrier unit 1 can be increased, and the plastic packaging stability can be increased.

[0056] Preferably, L4: L5 = 0.32.

[0057] On the basis of any of the above embodiments, the heat dissipation part 23 is further expanded; as Figure 3 As shown, the heat dissipation part 23 includes a first heat dissipation hole 232 and a second heat dissipation hole 233, the first heat dissipation hole 232 and the second heat dissipation hole 233 are arranged in parallel to the second center line, and the first heat dissipation hole 232 and the second heat dissipation hole 233 are the same structure, along the first center line direction, the first heat dissipation hole 232 and the second heat dissipation hole 233 are symmetrically arranged; a separation sheet is arranged between the first heat dissipation hole 232 and the second heat dissipation hole 233, so as to ensure the heat dissipation effect of the heat dissipation part 23 while ensuring the structural strength of the heat dissipation part 23.

[0058] Wherein, parallel to the second direction, the length of the separation sheet between the first heat dissipation hole 232 and the second heat dissipation hole 233 is not much different from the length of the first heat dissipation hole 232, and the distance between the end of the first heat dissipation hole 232 away from the separation sheet and the heat dissipation part 23 is slightly larger than the length of the first heat dissipation part 23, so as to ensure the sufficient structural strength of the heat dissipation part 23.

[0059] Further, as Figure 4 As shown, the heat dissipation part 23 is provided with an expansion hole 234, the expansion hole 234 is arranged at the end of the heat dissipation part 23 close to the first connecting part 21, when the lead frame is packaged, the expansion hole 234 can increase the connection strength of the plastic packaging agent and the heat dissipation part 23, and increase the plastic packaging effect.

[0060] In the embodiment, the first heat dissipation hole 232 and the second heat dissipation hole 233 are provided with a reaming hole 234, and the reaming hole 234 corresponds to a first reaming hole 234 and a second reaming hole 234. The first reaming hole 234 is arranged at the end of the first heat dissipation hole 232 away from the second heat dissipation hole 233, and the first reaming hole 234 extends in a direction away from the second heat dissipation hole 233 in parallel with the second center line direction. The second reaming hole 234 is arranged at the end of the second heat dissipation hole 233 away from the first heat dissipation hole 232, and the second reaming hole 234 extends in a direction away from the second heat dissipation hole 233 in parallel with the second center line direction.

[0061] Further, the reaming hole 234 is a rectangular structure, and in parallel with the second center line direction, the length of the reaming hole 234 is L6, and the length of the first heat dissipation hole 232 is L7, wherein L6:L7=1 / 3~2 / 5; in parallel with the first center line direction, the length of the upper end and the lower end of the reaming hole 234 is the same, and the length is L8, and the length of the first heat dissipation hole 232 is L9, wherein L8:L9=1 / 20~1 / 10. Thus, the size of the reaming hole 234 is controlled within a certain range, that is, the structural strength of the first connecting part 21 is not affected, and the heat dissipation effect of the heat dissipation hole is not affected, and the plastic sealing strength of the reaming hole 234 to the connecting unit 2 is ensured.

[0062] Preferably, L6:L7=0.35, and L8:L9=0.09.

[0063] Further, as shown in Figure 3 the reaming hole 234 is a trapezoidal structure, the end of the reaming hole 234 close to the first connecting sheet 211 is flush with the heat dissipation part 23, and the side of the reaming hole 234 away from the first connecting part 21 is an oblique side 2341. In parallel with the first center line direction, the included angle θ between the oblique side 2341 and the side of the heat dissipation part 23 is an acute angle, thereby increasing the structural strength of the reaming hole 234, reducing the stress concentration at the connection between the reaming hole 234 and the heat dissipation hole, and reducing the probability of easy breaking of the reaming hole 234 during plastic sealing. Preferably, the included angle is 45°.

[0064] It should be noted that the embodiments of the present application can be combined into new embodiments as long as the schemes do not conflict and the technical schemes can coexist.

[0065] The above has introduced the present application in detail, and the principle and implementation mode of the present application have been described by applying specific examples. The above embodiment is only used to help understand the present application and the core idea. It should be pointed out that for ordinary skilled in the art, without departing from the principle of the present application, the present application can be improved and modified in several ways, and these improvements and modifications also fall within the protection scope of the present application.

Claims

1. A leadframe, characterized by, The lead frame comprises a carrier unit (1), a connecting unit (2) and a pin unit (3), two carrier units (1) are connected by the connecting unit (2), and the pin unit (3) is arranged at one end of the carrier unit (1) away from the connecting unit (2); The connecting unit (2) comprises a first connecting part (21) and a heat dissipation part (23), the heat dissipation part (23) is symmetrically arranged on both sides of the first connecting part (21), and the first connecting part (21) is connected with the carrier units (1) on both sides in parallel to the first center line direction.

2. The lead frame according to claim 1, wherein The first connecting part (21) comprises a first connecting sheet (211) and a second connecting sheet (212), and the first connecting sheet (211) and the second connecting sheet (212) are rectangular structures; The second connecting sheet (212) is arranged at both ends of the first connecting sheet (211), and the end of the second connecting sheet (212) away from the first connecting sheet (211) is connected with the carrier unit (1); In parallel to the first center line direction, the length of the second connecting sheet (212) is greater than the length of the first connecting sheet (211).

3. The lead frame according to claim 2, wherein In parallel to the first center line direction, the length of the first connecting sheet (211) is L1, and the length of the second connecting sheet (212) is L2, wherein L1:L2 = 1 / 3-2 / 5; The length of the heat dissipation part (23) is L3, and L1:L3 = 1 / 3-2 / 5.

4. The lead frame according to claim 2, wherein The end of the second connecting sheet (212) close to the carrier unit (1) is provided with a heat dissipation opening (231), and the center line of the heat dissipation opening (231) is in the same straight line as the second center line; In parallel to the second center line direction, the length of the heat dissipation opening (231) is L4, and the length of the second connecting sheet (212) is L5, wherein L4:L5 = 1 / 3-2 / 5.

5. The lead frame according to claim 1, wherein The heat dissipation part (23) comprises a first heat dissipation hole (232) and a second heat dissipation hole (233), and the first heat dissipation hole (232) and the second heat dissipation hole (233) are arranged in parallel to the second center line; The first heat dissipation hole (232) and the second heat dissipation hole (233) are the same structure, and are symmetrically arranged along the first center line direction.

6. The lead frame according to claim 5, wherein The heat dissipation part (23) is provided with an enlarged hole (234), and the enlarged hole (234) is arranged at the end of the heat dissipation part (23) close to the first connecting part (21); The enlarged hole (234) extends in parallel to the second center line direction towards the carrier unit (1).

7. The lead frame according to claim 6, wherein Parallel to the second center line direction, the length of the expansion hole (234) is L6, and the length of the first heat dissipation hole (232) is L7, wherein L6:L7=1 / 3~2 / 5; Parallel to the first center line direction, the length of the expansion hole (234) is L8, and the length of the first heat dissipation hole (232) is L9, wherein L8:L9=1 / 20~1 / 10.

8. The lead frame of claim 7, wherein, the side of the expansion hole (234) away from the first connecting part (21) is an oblique side (2341), and parallel to the first center line direction, the included angle between the oblique side (2341) and the side of the heat dissipation part (23) is an acute angle.

9. The lead frame of claim 1, wherein, the connecting unit (2) further comprises a second connecting part (22), the middle part of the second connecting part (22) is connected with the end of the heat dissipation part (23) away from the first connecting part (21), and the two ends of the second connecting part (22) are connected with the pin unit (3); the lead frame comprises a first carrier group (11) and a second carrier group (12), and parallel to the first center line direction, the first carrier group (11) and the second carrier group (12) are connected through the heat dissipation part (23); wherein, the end of the heat dissipation part (23) away from the first connecting part (21) is provided with a positioning hole (4).

10. The lead frame of claim 8, wherein, the pin unit (3) comprises a pin part (31) and a soldering leg part (32), the soldering leg part (32) is connected with the pin part (31), and the pin part (31) is connected with the second connecting part (22); wherein, the second connecting part (22) is provided with a bending piece (221).

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