CN100514615C

CN100514615C - Producing method of micro link lug structure with stress buffer

Info

Publication number: CN100514615C
Application number: CNB200610073138XA
Authority: CN
Inventors: 许永昱; 廖锡卿; 谭瑞敏; 郑智元
Original assignee: Industrial Technology Research Institute ITRI
Current assignee: Industrial Technology Research Institute ITRI
Priority date: 2006-04-06
Filing date: 2006-04-06
Publication date: 2009-07-15
Anticipated expiration: 2026-04-06
Also published as: CN101051628A

Abstract

The lug structure includes following parts: a first top surface connected to one of base plate and electronic module; a second top surface connected to one of base plate and electronic module; a support body connected between the first top surface and the second top surface, and surface areas at two ends of the support body are not larger than surfaces of the first top surface and the second top surface; being setup outside the support body, the buffer layer provides functions for absorbing stress and buffered effect.

Description

The manufacture method of the micro link lug structure of tool stress buffer

Technical field

The present invention relates to a kind of manufacture method of micro link lug structure of tool stress buffer; relate in particular to a kind of problem that traditional high-order packaged chip can't bear vertical and lateral stress that solves; utilize a composite projection with stress buffer effect to carry out being connected between electronic building brick and circuit; this projection has to bear and disperses vertically and the function of lateral stress; can be in the manufacture process of encapsulation effectively protection electronic building brick and circuit, can reach the buffer structure of the simple and easy and high-reliability of manufacture process.

Background technology

Advancing by leaps and bounds of semiconductor industry, all electronic products all can be designed to gently, thin, short, little framework, because the IC assembly of electronic product all has high pin number in design, high transmission speed and multifunctional direction ... the characteristic that waits, for realizing above-mentioned purpose, the IC manufacture process all develops towards the following manufacture process of 90 nanometers, and use low-k (Low-K) material to carry out the making of the little binding of inner lead, therefore also producing on package fabrication process has technical bottleneck, for example: the selecting for use of IC material, package fabrication process is to the impact stress and the diastrophic variety of problems of chip body.

The envelope survey technology of present high-order, as: BGA, Fine Pitch, Flip-Chip, CSP... etc., after connected mode between its chip and the substrate is all and uses the Solder Bumps reflow, carry out the connection between the two again, but when carrying out in this way, chip must bear the thermal stress of suitable high temperature and impact, produced between chip and substrate vertically simultaneously and horizontal stress, therefore this chip may produce damage or structural destruction, influenced the reliability of chip after assembling, qualification rate when having reduced production, especially the chip in the following manufacturing of 90 nanometers all adopts the low-k material, thermal stress ability to bear for high temperature is not good, seems considerably important so utilize the encapsulation of low stress to engage manufacture process.

See also U.S. Pat 5783465 and disclose, it adds that for utilizing the projection reflow primer (Underfill) filling is to protect and reinforcement.Moreover, U.S. Pat 6818544 and US6555759 two patent cases are all utilizes composite projection (Compliant Bump) in conjunction with conductive particle glued membrane (Conductive Film), above-mentioned three United States Patent (USP)s all use glue materials such as primer and stick together, may because of when heating the primer coefficient of expansion differ, its reliability that thermal stress is born not is so high, must increase many extra manufacture processes simultaneously, can improve cost of manufacture simultaneously, so these three prior aries are quoted case as proof and are all had improved space.

Summary of the invention

Based on the defective that solves the above prior art; the present invention is the micro link lug structure and the manufacture method of tool stress buffer; its main purpose can't be born vertically and the problem of lateral stress for solving traditional high-order packaged chip; utilize a composite projection with stress buffer effect to carry out being connected between electronic building brick and circuit; this projection has to bear and disperses vertically and the function of lateral stress; can be in the manufacture process of encapsulation effectively protection electronic building brick and circuit, can reach the buffer structure of the simple and easy and high-reliability of manufacture process.

For realizing above-mentioned purpose, the manufacture method of little binding projection of tool stress buffer of the present invention comprises:

The capillary that plural number has been cut predetermined length is fixed in the corresponding plurality of fixed mould;

Plural number capillary open-work utilizes plating mode, and metal material is plated in this open-work top, to form first end face;

Plural fixed mould and capillary are implemented overturning step, and make capillary first end face be positioned at the capillary below, the upper end of capillary open-work is not closed yet, at this moment, utilize electroplating metal material again in open-work, to form a supporter, utilize excessive electro-plating method to make the capillary top continue to form second end face again; And

Behind plural fixed mould removal, promptly form this little binding projection.

First end face of this little binding projection, supporter and second end face are all copper product and constitute.

This capillary is constituted by the macromolecular material of a low-k.

This macromolecular material is constituted by a polyimides.

Describe the present invention below in conjunction with the drawings and specific embodiments, but not as a limitation of the invention.

Description of drawings

Fig. 1 is the first enforcement structure chart of little binding projection of tool stress buffer of the present invention;

Fig. 2 is that little binding projection of tool stress buffer of the present invention is applied to the enforcement illustration between electronic building brick and the substrate;

Fig. 3 is the second enforcement structure chart of little binding projection of tool stress buffer of the present invention;

Fig. 4 is the 3rd enforcement structure chart of little binding projection of tool stress buffer of the present invention;

Fig. 5 is the 4th enforcement structure chart of little binding projection of tool stress buffer of the present invention;

Fig. 6 A is the first pass figure of the manufacturing of little binding projection of tool stress buffer of the present invention;

Fig. 6 B is second flow chart of the manufacturing of little binding projection of tool stress buffer of the present invention;

Fig. 6 C is the 3rd flow chart of the manufacturing of little binding projection of tool stress buffer of the present invention;

Fig. 6 D is the 4th flow chart of the manufacturing of little binding projection of tool stress buffer of the present invention;

Fig. 6 E is the 5th flow chart of the manufacturing of little binding projection of tool stress buffer of the present invention;

Fig. 6 F is the 6th flow chart of the manufacturing of little binding projection of tool stress buffer of the present invention;

Fig. 7 A is the first pass figure of another manufacturing of little binding projection of tool stress buffer of the present invention;

Fig. 7 B is second flow chart of another manufacturing of little binding projection of tool stress buffer of the present invention;

Fig. 7 C is the 3rd flow chart of another manufacturing of little binding projection of tool stress buffer of the present invention;

Fig. 7 D is the 4th flow chart of another manufacturing of little binding projection of tool stress buffer of the present invention.

Wherein, Reference numeral

11,21,31,41～the first end faces

12,22,32,42～the second end faces

13,23,33,43～supporter

14,24,34,44～resilient coating

15～electronic building brick

151～weld pad

152～conductor layer

16～substrate

161～weld pad

162～conductor layer

51～metal base

52～polyimides

53～light shield

54～etch-hole

55～columnar metal body

56～metal material layer

57～staking punch

61～fixed mould

62～capillary

621～open-work

63～the first end faces

64～supporter

65～the second end faces

Embodiment

See also shown in Figure 1, for first of little binding projection of tool stress buffer of the present invention is implemented structure chart, wherein this projection includes one first end face 11, one of them is connected this first end face 11 and substrate and electronic building brick, and wherein electronic building brick is made a general reference general chip (Chip) or other utilizes the integrated circuit (IC) of surface soldered technology (SMT).One second end face 12, one of them is connected this second end face 12 and substrate and electronic building brick, and this electronic building brick also refers to chip or integrated circuit certainly; One supporter 13 is connected between first end face 11 and second end face 12, and two end surface area of this supporter 13 are not more than first end face 11 and second end face 12, and present embodiment is a column.And the syndeton of this first end face 11, second end face 12 and supporter 13 can provide to form between substrate and the electronic building brick to electrically connect; One resilient coating 14, be arranged at the outside of supporter 13, so that the function of stress absorption and buffering to be provided, this resilient coating 14 is constituted by the macromolecular material of a low-k (Low-K), and the macromolecular material of this low-k is a polyimides (Polyimide, PI) constitute, and utilize the wherein a kind of mode that coats, fills to be arranged at the outside of supporter 13.

See also shown in Figure 2, for little binding projection of tool stress buffer of the present invention is applied to enforcement illustration between electronic building brick and the substrate, find out clearly that wherein projection cube structure of the present invention is arranged between electronic building brick 15 (present embodiment is a chip) and the substrate 16, it is provided with the position between electronic building brick weld pad 151 and substrate weld pad 161, and electronic building brick weld pad 151 is connected with its conductor layer 152; Relatively, substrate weld pad 161 also is connected with its conductor layer 162.And this projection and have electronic building brick 15 and substrate 16 between the function that electrically connects, have the effect of stress buffer by resilient coating on the projection, can effectively protect electronic building brick 15 and substrate 16 not to be subjected to laterally extraneous or longitudinal pulling force influences.

See also shown in Figure 3, for second of little binding projection of tool stress buffer of the present invention is implemented structure chart, the member that also includes first end face 21, second end face 22 and resilient coating 24, the difference of itself and framework that Fig. 1 discloses is that its supporter 23 is designed to spring body, therefore this spring body supporter 23 meet with stresses and coefficient of elasticity and Fig. 1 to disclose column supporter 13 identical anything but, can provide in the package fabrication process and go up different considerations with the base plate stress design, and make package fabrication process can obtain the optimization structure for electronic building brick.

See also shown in Figure 4; for the 3rd of little binding projection of tool stress buffer of the present invention is implemented structure chart; also include first end face 31; the member of second end face 32 and resilient coating 34; be that with the difference of framework that Fig. 1 discloses its supporter 33 is designed to three columns that diameter is less; certainly the skilled personnel are not subject to this; utilize the complex root column as supporter 33 structures; all in protection scope of the present invention; and should plural number column supporter 33 meet with stresses and coefficient of elasticity and Fig. 1 to disclose single column supporter 13 also inequality, the variation for electronic building brick and base plate stress design also is provided in the package fabrication process.

See also shown in Figure 5, for the 4th of little binding projection of tool stress buffer of the present invention is implemented structure chart, the member that also includes first end face 41, second end face 42 and resilient coating 44, the difference of itself and framework that Fig. 1 discloses is that its supporter 43 is designed to helicoid, therefore this helicoid supporter 43 meet with stresses and coefficient of elasticity and Fig. 1 to disclose column supporter 13 identical anything but, the variation that designs for electronic building brick and base plate stress also is provided in the package fabrication process.

See also shown in Fig. 6 A to Fig. 6 F, flow chart for the manufacturing of little binding projection of tool stress buffer of the present invention, it is with polyimides (Polyimide, PI) 52 utilize a pressure sintering (Lamination) to be arranged at a metal base (second end face) 51 tops, this metal base 51 is made of Copper Foil, and this polyimide 52 carries out etching program (Etching) in a suitable spacing, in plural light shield 53 not shelter to be formed with plural etch-hole 54, and should plural number etch-hole 54 and utilize plating mode (Electro-Plating) and with the metal material filling in etch-hole 54, to form a columnar metal body (supporter) 55, and form with the metal base 51 of bottom and to electrically connect, utilize (Over Electro-Plating) method of excessively electroplating again or make columnar metal body 55 and polyimide 52 tops form a planar metal material layer (first end face) 56 with pressure sintering in metal material, certain above-mentioned metal material 56, columnar metal body 55 or metal base 51 are all copper and constitute, therefore can make second end face, all can form electric connection between the supporter and first end face, last step is for utilizing a mechanical compression strength, and using a plurality of staking punch 57 that aforementioned formation structure is stamped into a plurality of little connection projections, this is little binding projection manufacture process of tool stress buffer proposed by the invention.

See also shown in Fig. 7 A to Fig. 7 D, flow chart for another manufacturing of little binding projection of tool stress buffer of the present invention, wherein Fig. 7 A shows a kind of capillary 62, when being generally the production chemical detection, these capillary 62 purposes use, this capillary 62 is constituted by the macromolecular material of a low-k (Low-K), same macromolecular material also can be a polyimides, and capillary 62 centers are the open-work 621 of a hollow form.The capillary 62 that plural number has been cut predetermined length is fixed in the corresponding plurality of fixed mould 61, Fig. 7 B then discloses plural capillary 62 open-works 621 and utilizes plating mode (Electro-Plating) and metal material is plated in these open-work 621 tops, this metal material is constituted by copper, to form first end face 63, Fig. 7 C then discloses plural fixed mould 61 and capillary 62 is implemented overturning step, and make capillary 62 first end faces 63 be positioned at capillary 63 belows, the upper end of capillary 62 open-works 621 is not closed yet, at this moment, utilize electroplating metal material again in open-work 621, this metal material is also constituted by copper, to form a supporter 64, utilize (Over Electro-Plating) method of excessively electroplating to make capillary 63 tops continue to form second end face 65 again, Fig. 7 D discloses behind plural fixed mould 61 removals, promptly form this little binding projection, and first end face of this little binding projection, the supporter and second end face are all copper product and constitute.

Can learn by above-mentioned disclosed accompanying drawing; the present invention is different from prior art and utilizes Solder Bumps to coat the encapsulation joint manufacture process that a primer is applied to low stress; and adopt a metallic conduction material as electrically connecting main body; and this electric connection main body includes one first end face, a supporter and one second end face; again in outer setting one resilient coating of support portion; this resilient coating has the effect of stress buffer, can effectively protect chip and substrate be not subjected to extraneous laterally or longitudinal pulling force influence.In addition, little connection projection cube structure of tool stress buffer of the present invention is to make separately, each projection is all an I/O (I/O) contact, when assembling, only need this projection placed and directly do contraposition between chip and the substrate and engage and get final product, this kind connected mode compared with prior art, advantage is not for to need to use the glue material and to increase the manufacture process that layer manufacture process done stress buffer, and different package fabrication process needs the projection of different spring ratios, all can make a change by the resilient coating or the employing difformity supporter that coat different spring ratios, not as good as the effect that can adopt plural supporter also can reach to change coefficient of elasticity, therefore can provide the optimization structure that is applied to package fabrication process after the projection experiment with computing.

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

Claims

1, a kind of manufacture method of little binding projection of tool stress buffer is characterized in that, comprising:

2, the manufacture method of little binding projection of tool stress buffer according to claim 1 is characterized in that, first end face of this little binding projection, supporter and second end face are all copper product and constitute.

3, the manufacture method of little binding projection of tool stress buffer according to claim 1 is characterized in that, this capillary is constituted by the macromolecular material of a low-k.

4, the manufacture method of little binding projection of tool stress buffer according to claim 1 is characterized in that, this macromolecular material is constituted by a polyimides.