CN201699010U

CN201699010U - Lead frame structure

Info

Publication number: CN201699010U
Application number: CN 201020194574
Authority: CN
Inventors: 李盈钟
Original assignee: LEFRAM TECHNOLOGY CORP
Current assignee: LEFRAM TECHNOLOGY CORP
Priority date: 2010-05-12
Filing date: 2010-05-12
Publication date: 2011-01-05
Anticipated expiration: 2020-05-12

Abstract

The utility model provides a lead frame structure which comprises a chip seat, a plurality of pins and at least one supporting pin, wherein the supporting pin is arranged between the two pins, certain space exists between the two pins adjacent to the supporting pin, and the space is larger than the minimum space between the two adjacent pins so as to avoid short-circuit condition between the supporting pin and the pins due to residual tins in the welding process.

Description

Conducting wire frame structure

Technical field

The utility model relates to a kind of conducting wire frame structure that is applied to semiconductor subassembly, particularly a kind of conducting wire frame structure with feet.

Background technology

It act as the interior electronic building brick function of transmission integrated circuit to outside system board lead frame.On making, with chemical etching or mechanical stamping mode, on copper alloy or iron-nickel alloy sheet with integrated circuit foot rest shape imprinting moulding.

In semiconductor packaging process, the lead frame slide glass can be put to the encapsulating mould of molding press earlier, then the good epoxy resin of preheating is put into the resin feeding mouth of encapsulating mould, treat the epoxy resin cooling curing after, can finish packaging body.In encapsulation process, the packaging body of moulding in advance can be reserved a fluting in a side of lead frame slide glass, for the setting of follow-up chip (as: photoelectric chip).After the chip installation, utilize cover plate to cover fluting again, finish the step that chip is provided with.

Wherein, lead frame has a plurality of pins, and pin is divided into two groups and be arranged in the limit, two opposite sides of lead frame separately.Also be provided with packaging body on the lead frame, a side of packaging body have one the fluting can be in order to carries chips (as: photoelectric chip).

And the semiconductor package product high as the I/O number, if under the prerequisite that does not increase package dimension, the I/O number is high certainly will will to make the spacing of pin dwindle, but will make in the welding procedure more difficult thus, and in welding procedure, form solder residue between two pins easily, and then make and form short circuit between two pins in making.Therefore, in the process of lead frame design, must reserve the minimum spacing (safe spacing) between two pins, take place, promote the yield of semiconductor product with the situation of avoiding short circuit.

See also Fig. 1, be a kind of lead frame 100 with feet 10.Feet 10 is connected in chip carrier 20 and between two adjacent pins 12.Fig. 2 is the schematic diagram of lead frame 100 after carrying out encapsulation step along axis 11.As can be seen from Figure 2, after lead frame 100 was finished encapsulation, feet 10 can partly be residued on the lead frame 100.And the feet 10 of this part will cause the residual of tin material in lead frame 100 in follow-up welding procedure.As shown in Figure 3, lead frame 100 can form first space 14 owing to feet 10 is adjacent 12 of two pins, and tin material 15 can residue in lead frame 100 by first space 14 in follow-up welding procedure.In this, in the test process of follow-up chip, may cause the circuit unit short circuit, and then cause the problem of the electrical reliability of chip because of being infected with of tin material 15.

Summary of the invention

The purpose of this utility model is, solves the lead frame that prior art has supporting foot structure, and it is residual to have a tin material, and then has influence on the problem of electrical reliability and propose a kind of conducting wire frame structure.

The conducting wire frame structure that provides of the present utility model includes a chip carrier, many pins and at least one feet.Wherein, has one first spacing between two adjacent pins.Feet is connected in chip carrier, and feet is between two adjacent pins; It is characterized in that: have one second spacing between two pins adjacent with feet, second spacing is greater than first spacing.

Above-mentioned conducting wire frame structure, wherein, the two pins adjacent with feet is first pin, all the other pins are second pin.Second pin has a junction that is adjacent to chip carrier, and a contact site that extends from connecting portion central authorities.

Above-mentioned conducting wire frame structure, wherein, the width of connecting portion is greater than the width of contact site.

The utility model also proposes another kind of conducting wire frame structure, comprises a chip carrier, many pins and at least one feet.Wherein, feet is connected in chip carrier, and feet is between two adjacent pins.

The two pins adjacent with feet is first pin, and all the other pins are second pin.Second pin has one second connecting portion that is adjacent to chip carrier, and one second contact site that extends from second connecting portion central authorities.Wherein, two sides of second connecting portion respectively have the one second reinforcement wing.

First pin has one first connecting portion that is adjacent to chip carrier, and one first contact site that extends from first connecting portion central authorities.Wherein, first connecting portion has the one first reinforcement wing adjacent to a side of second pin.

The conducting wire frame structure that the utility model proposed, because its special architectural feature, for this reason, this kind conducting wire frame structure can be in order to solve the problem of aforementioned wire shelf structure easy residual tin material in welding procedure.

Below in conjunction with the drawings and specific embodiments the utility model is described in detail, but not as to qualification of the present utility model.

Description of drawings

Fig. 1 is an existing conducting wire frame structure;

Fig. 2 is the schematic diagram of conducting wire frame structure after encapsulation of Fig. 1;

Fig. 3 is the partial enlarged drawing of Fig. 2;

Fig. 4 is the conducting wire frame structure according to an embodiment of the present utility model;

Fig. 5 is the partial enlarged drawing of Fig. 6; And

Fig. 6 is the conducting wire frame structure according to another embodiment of the present utility model.

Wherein, Reference numeral

10 feets

11 axis

12 pins

14 first spaces

14 ' second space

15 tin material

20 chip carriers

100 lead frames

400 lead frames

402 chip carriers

404 pins

406 feets

408 first pins

410 second pins

412 connecting portions

414 contact sites

D1 first spacing

D1 ' first spacing

D2 second spacing

D2 ' second spacing

600 lead frames

602 chip carriers

604 pins

606 feets

608 first pins

610 second pins

612 second connecting portions

614 second contact sites

616 first connecting portions

618 first contact sites

620 second strengthen the wing

622 first strengthen the wing

Embodiment

Below in conjunction with accompanying drawing structural principle of the present utility model and operation principle are done concrete description:

According to the conducting wire frame structure of an embodiment of the present utility model, as shown in Figure 4.

Lead frame 400 comprises a chip carrier 402, many pins 404 and at least one feet 406.Wherein feet 406 is connected in chip carrier 402, and feet 406 is between two adjacent pins 404.

Pin 404 can be divided into first pin 408 and second pin 410.Wherein, first pin 408 is to be pin adjacent with feet 406 in the pin 404.The pin 404 of non-first pin 408 is second pin 410.

Second pin 410 comprises an a junction 412 and a contact site 414.Wherein connecting portion 412 is the parts that are adjacent to chip carrier 402 for second pin 410, and contact site 414 is the parts that extend out from connecting portion 412 central authorities for second pin 410.Since lead frame 400 size-constrained in packaging technology thermal effect and make pin 404 buckling deformations easily, for this reason, the width of connecting portion 412 can be designed to the width greater than contact site 414 when design.

Two first pins 408 adjacent with feet 406 have one second spacing d2, and two 410 adjacent of second pins have one first spacing d1.

Wherein, first pin 408 can a cutter punching press pin 404 and is formed.Or rather, can two cutters practise physiognomy over the ground punching press pin 404 and forming of first pin 408.By this kind punch steps, can make the second spacing d2 of 408 of two first pins adjacent broaden with feet 406, and greater than the first spacing d1.Because this architectural feature, so that lead frame 400 is through in the follow-up welding procedure, as shown in Figure 5, second space 14 ' seems with respect to first space 14 among Fig. 3 and is difficult for the residual tin material by broad for this reason.Whereby, lead frame 400 can effectively be evaded the existing subsequent conditioning circuit problem of short-circuit that causes because of the tin material is residual.

According to the conducting wire frame structure of another embodiment of the present utility model, as shown in Figure 6.

Lead frame 600 comprises a chip carrier 602, many pins 604 and at least one feet 606.Wherein feet 606 is connected in chip carrier 602, and feet 606 is between two adjacent pins 604.

Pin 604 can be divided into first pin 608 and second pin 610.Wherein, first pin 608 is to be pin adjacent with feet 606 in the pin 604.The pin 604 of non-first pin 608 is second pin 610.

Second pin 610 comprises one second connecting portion 612 and one second contact site 614.Wherein second connecting portion 612 is the parts that are adjacent to chip carrier 602 for second pin 610.Second contact site 614 is the parts that extend out from second connecting portion, 612 central authorities for second pin 610.Two sides of second connecting portion 612 respectively have one second and strengthen the wing 620.

First pin 608 comprises one first connecting portion 616 and one first contact site 618.Wherein first connecting portion 616 is the parts that are adjacent to chip carrier 602 for first pin 608.First contact site 618 is the parts that extend out from first connecting portion, 616 central authorities for first pin 608.First connecting portion 616 has the one first reinforcement wing 622 adjacent to a side of second pin 610.

Be formed at the side of first pin 608 because first strengthens the wing 622, and there is no the formation of the first reinforcement wing 622 in its side adjacent to feet 606 adjacent to second pin 610.For this reason, the second spacing d2 ' of 608 of two first pins adjacent with feet 606 also can be greater than the first spacing d1 ' of 610 of two adjacent second pins.Architectural feature in the welding procedure of lead frame 600 after encapsulation, also can effectively be evaded the existing subsequent conditioning circuit problem of short-circuit that causes because of the tin material is residual whereby.

In this, what deserves to be mentioned is that having first first pin, 608 structures of strengthening the wing 622 is not as limit.For example; first pin 608 also optionally is provided with the reinforcement wing structure in its side adjacent to feet 606, and only the second spacing d2 ' of 608 of two first pins all belongs to protection range of the present utility model greater than the first spacing d1 ' person of 610 of two adjacent second pins.

Certainly; the utility model also can have other various embodiments; under the situation that does not deviate from the utility model spirit and essence thereof; those of ordinary skill in the art work as can make various corresponding changes and distortion according to the utility model, but these corresponding changes and distortion all should belong to the protection range of the appended claim of the utility model.

Claims

1. conducting wire frame structure, include a chip carrier, many pins and at least one feet, has one first spacing between two adjacent pins of these a plurality of pins, this feet is connected in this chip carrier and between these a plurality of pins two adjacent pins wherein, it is characterized in that, have one second spacing between two these pins adjacent with this feet, this second spacing is greater than this first spacing.

2. conducting wire frame structure according to claim 1, it is characterized in that, two pins adjacent to this feet are first pin, and all the other these a plurality of pins are second pin, and these a plurality of second pins have a junction that is adjacent to this chip carrier and the contact site that extends of these connecting portion central authorities certainly.

3. conducting wire frame structure according to claim 2 is characterized in that the width of this connecting portion is greater than the width of this contact site.

4. conducting wire frame structure, include a chip carrier, many pins and at least one feet, this feet is connected in this chip carrier and between these a plurality of pins two adjacent pins wherein, two these pins adjacent to this feet are first pin, all the other these a plurality of pins are second pin, these a plurality of second pins have one second connecting portion that is adjacent to this chip carrier and one second contact site that extends of these second connecting portion central authorities certainly, two sides of this second connecting portion respectively have one second and strengthen the wing, this first pin has one first connecting portion that is adjacent to this chip carrier and one first contact site that extends of these first connecting portion central authorities certainly, and this first connecting portion has one first adjacent to a side of this second pin and strengthens the wing.