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CN-224234192-U - Lead frame

CN224234192UCN 224234192 UCN224234192 UCN 224234192UCN-224234192-U

Abstract

The utility model discloses a lead frame which comprises a first frame and a second frame, wherein the first frame is provided with a yielding hole, the inner wall of a frame of the yielding hole is connected with a plurality of pins, at least part of the pins are downwards protruded relative to the lower surface of the frame, the second frame is provided with a bonding pad, the outer peripheral wall of the bonding pad is provided with a supporting bar which extends outwards, the second frame is arranged on the lower side of the first frame, the bonding pad is positioned in the projection of the yielding hole in the vertical direction and is arranged at intervals with each pin, the supporting bar extends to the lower side of the frame, the level of the upper surface of the bonding pad is lower than that of the upper surface of the pins, and the lower surface of the bonding pad is flush with the lower surface of the pins. Therefore, the chip can be conveniently mounted on the upper surface of the bonding pad, the chip is located in the yielding hole, meanwhile, the height difference between the chip after being mounted and the pins can be reduced, the overall thickness of the lead frame after chip packaging is reduced, and the miniaturization of chip packaging is facilitated.

Inventors

  • LIN YINGHONG
  • YANG XIAOFAN
  • LIN BIN

Assignees

  • 英通微半导体材料(中山)有限公司

Dates

Publication Date
20260512
Application Date
20250418

Claims (10)

  1. 1. A lead frame, comprising: The first frame (100) is provided with a first frame unit (110), the first frame unit (110) is provided with a yielding hole (120) which is arranged along the up-down direction, the inner wall of a frame (121) of the yielding hole (120) is connected with a plurality of pins (130) which extend towards the inside of the yielding hole (120), all the pins (130) are arranged at intervals along the circumferential direction of the yielding hole (120), and at least part of the pins (130) are downwards protruded relative to the lower surface of the frame (121); A second frame (200) having a second frame unit (210) corresponding to the first frame unit (110), the second frame unit (210) being provided with a bonding pad (220), an outer peripheral wall of the bonding pad (220) being provided with an outwardly extending support bar (230); The second frame (200) is disposed at the lower side of the first frame (100), the bonding pads (220) are disposed in the projection in the vertical direction and are spaced from the pins (130), the supporting bars (230) extend to the lower side of the frame (121), the upper surfaces of the bonding pads (220) are used for mounting chips (400), and the upper surfaces of the bonding pads (220) are lower than the upper surfaces of the pins (130), and the lower surfaces of the bonding pads (220) are flush with the lower surfaces of the pins (130).
  2. 2. The lead frame according to claim 1, wherein a lower surface of the first frame (100) is etched upward with first etched grooves (122) arranged along a circumferential direction of the relief holes (120), the first etched grooves (122) are located below the frame (121), a depth of the first etched grooves (122) is smaller than a thickness of the first frame (100), a thickness of the pins (130) protruding downward with respect to the frame (121) is equal to the depth of the first etched grooves (122), and an upper surface of the pins (130) is flush with an upper surface of the frame (121).
  3. 3. The leadframe according to claim 2, characterized in that the free ends of the pins (130) further have an extension (140) extending near the center of the relief hole (120), A second etching groove (141) is etched upwards on the lower surface of the first frame (100) and is positioned below the extension part (140), so that the pin (130) protrudes downwards relative to the extension part (140), and the upper surface of the extension part (140) is flush with the upper surface of the pin (130); Or the upper surface of the first frame (100) is etched with a third etching groove above the extension part (140) downwards, so that the pin (130) protrudes upwards relative to the extension part (140), and the lower surface of the extension part (140) is flush with the lower surface of the pin (130).
  4. 4. A lead frame according to claim 3, characterized in that a side surface of the lead (130) flush with the extension (140) is etched with a fourth etched groove (131), the depth of the fourth etched groove (131) being smaller than the thickness of the first frame (100).
  5. 5. The lead frame according to claim 1, wherein the pad (220) includes an upper mounting portion (221) and a lower mounting portion (222), the upper mounting portion (221) is located above the lower mounting portion (222), and an outer periphery of the upper mounting portion (221) is arranged to extend outwardly with respect to the lower mounting portion (222), and the support bar (230) is connected to an outer periphery of the upper mounting portion (221); The upper surface of the upper mounting part (221) is lower than the upper surface of the pin (130), and the lower surface of the lower mounting part (222) is flush with the lower surface of the pin (130).
  6. 6. The lead frame according to claim 5, wherein a fifth etching groove (240) is etched upward along a circumferential direction of the lower mounting portion (222) on a lower surface of the second frame (200) such that the upper mounting portion (221) and the support bar (230) are both located above the fifth etching groove (240), and a thickness of the lower mounting portion (222) is equal to a depth of the fifth etching groove (240).
  7. 7. The lead frame according to any one of claims 1 to 6, wherein a plastic package portion (300) is filled between the first frame (100) and the second frame (200), the leads (130) are embedded in the plastic package portion (300) and the upper surfaces of the leads (130) are flush with the upper surface of the plastic package portion (300), the support bars (230) are embedded in the plastic package portion (300), mounting grooves (310) corresponding to the bonding pads (220) one by one are formed in the upper surface of the plastic package portion (300), the upper surfaces of the bonding pads (220) are at least partially located in the projection of the mounting grooves (310) in the up-down direction, and the lower surfaces of the leads (130) and the bonding pads (220) are flush with the lower surface of the plastic package portion (300).
  8. 8. The lead frame according to any one of claims 1 to 6, wherein the first frame (100) is provided with a first positioning portion located outside the first frame unit (110), the second frame (200) is provided with a second positioning portion located outside the second frame unit (210), one of the first positioning portion and the second positioning portion is provided with a positioning hole, and the other is provided with a positioning post capable of being inserted and connected with the positioning hole in a matching manner.
  9. 9. The lead frame according to any one of claims 1 to 6, wherein the number of the first frame units (110) and the second frame units (210) is at least two, two adjacent first frame units (110) are connected to each other by the corresponding frame (121), and two adjacent second frame units (210) are connected to each other by the corresponding support bar (230).
  10. 10. The lead frame according to any one of claims 1 to 6, wherein the first frame (100) and the second frame (200) are each copper, and the outer surfaces of the first frame (100) and the second frame (200) are each provided with a plating layer.

Description

Lead frame Technical Field The utility model relates to the technical field of chip packaging, in particular to a lead frame. Background In the prior art, when the lead frame is subjected to plastic packaging, pins and bonding pads for mounting chips are formed on the frame through processes such as etching, electroplating and the like, and then epoxy resin or other plastic packaging materials are subjected to plastic packaging on the lead frame through an injection mold to form the required lead frame. Disclosure of utility model The present utility model aims to solve at least one of the technical problems existing in the prior art. Therefore, the utility model provides the lead frame which can improve the overall thickness of the lead frame after chip packaging. The lead frame comprises a first frame body, a second frame body and a bonding pad, wherein the first frame body is provided with a first frame unit, the first frame body is provided with a yielding hole which is arranged along the up-down direction, the inner wall of a frame of the yielding hole is connected with a plurality of pins which extend towards the inner part of the yielding hole, all the pins are arranged at intervals along the circumference of the yielding hole, the pins are at least partially protruded downwards relative to the lower surface of the frame, the second frame body is provided with a second frame body corresponding to the first frame body, the second frame body is provided with a bonding pad, the outer peripheral wall of the bonding pad is provided with a supporting bar which extends outwards, the second frame body is arranged on the lower side of the first frame body, the bonding pad is located in the projection of the up-down direction and is arranged at intervals with each pin, the supporting bar extends to the lower side of the frame body, the upper surface of the bonding pad is used for mounting a chip, the level of the upper surface of the bonding pad is lower than the level of the upper surface of the pins, and the lower surface of the bonding pad is flush with the lower surface of the bonding pad. The lead frame provided by the embodiment of the utility model has at least the following beneficial effects: In the lead frame of the embodiment of the utility model, the lead frame is divided into the first frame and the second frame which are independent of each other, and the pins and the bonding pads are respectively arranged on the first frame and the second frame, so that independent processing of the pins and the bonding pads can be conveniently carried out. In addition, offer the hole of stepping down through offering on the first frame unit of first frame to set up the pin in the inner peripheral wall of hole of stepping down, through set up the pad on the second frame unit of second frame, and set up the support bar of outwards extending at the periphery wall of pad, from this, when the equipment, can install the top at the second frame with first frame directly, and make the pad lie in the projection of the hole of stepping down that corresponds and with each pin interval arrangement, the hole of stepping down can step down to the pad in order to expose the pad, from this can be convenient install the chip in the upper surface of pad and make the chip lie in the hole of stepping down, and because the level of the upper surface of pad is less than the level of pin upper surface, from this then can reduce the difference in height between chip installation back and the pin, thereby can improve the roughness of chip package back lead frame upper surface, reduce the whole thickness of chip package back lead frame, be favorable to the miniaturization of chip package, and improve the whole thermal diffusivity after the chip package. According to some embodiments of the utility model, a first etching groove is etched on the lower surface of the first frame upwards along the circumferential direction of the relief hole, the first etching groove is located below the frame, the depth of the first etching groove is smaller than the thickness of the first frame, the downward protruding thickness of the pin relative to the frame is equal to the depth of the first etching groove, and the upper surface of the pin is flush with the upper surface of the frame. According to some embodiments of the utility model, the free end of the pin further has an extension portion extending near the center of the relief hole, the lower surface of the first frame is etched with a second etching groove below the extension portion upward so that the pin protrudes downward with respect to the extension portion and the upper surface of the extension portion is flush with the upper surface of the pin, or the upper surface of the first frame is etched with a third etching groove above the extension portion downward so that the pin protrudes upward with respect to the extension portion and the lower surface of the extension portion is flush with th