CN101851775A

CN101851775A - Electroplating hanging element suitable for manufacturing of through silicon via (TSV) by bottom-to-top electroplating method

Info

Publication number: CN101851775A
Application number: CN 201010200009
Authority: CN
Inventors: 曹毓涵; 罗乐
Original assignee: Shanghai Institute of Microsystem and Information Technology of CAS
Current assignee: Shanghai Institute of Microsystem and Information Technology of CAS
Priority date: 2010-06-11
Filing date: 2010-06-11
Publication date: 2010-10-06

Abstract

The invention relates to an electroplating hanging element suitable for the manufacturing of a through silicon via (TSV) by a bottom-to-top electroplating method. The electroplating hanging element is characterized by comprising a main body structure and a stainless steel block, wherein the main body structure is of a shape similar to a square tennis racket; the main body part of the racket is a square which has four rounded corners; a circular recess for accommodating a chip is reserved in the center of the square; six open holes for accommodating T-shaped bolts are reserved around the square; a handle of the racket is rectangular and sequentially fixes an organic glass plate, a rubber sheet and a silicon chip on the main body part of the main body structure by the bolts; thin copper paper is laid on the back of the silicon chip and is electrically contacted with a seed layer on the back of the silicon chip through a copper wire; and the copper wire is electrically connected with the stainless steel block on the back of the main body structure by the bolt. The electroplating hanging element has the characteristics of simplicity, practicality and capability of providing good electric contact and improving the efficiency of via metallization.

Description

A kind of plating suspension member that is applicable to the TSV of electro-plating method making from bottom to top

Technical field

The present invention relates to a kind of making and wear the employed plating suspension member of silicon vertical through hole (Through Silicon Via), relate to a kind of plating suspension member that is applicable to the TSV of electro-plating method making from bottom to top or rather.Belong to MEMS packaging process field.

Background technology

MEMS (micro-electro-mechanical system) is meant the collection microsensor that adopts Micrometer-Nanometer Processing Technology to make, micro parts, and miniature performer, signal processing, pilot circuits etc. are in the system of one.The MEMS device all has very wide application prospect in a lot of fields.Yet, in the MEMS device, containing moving parts, these moving partss are very fragile, very easily are subjected to the dust in scribing and the assembling process, humidity, the influence of factors such as machinery, thus cause the overall performance of components from being damaged or device to descend.Therefore, must take the MEMS encapsulation technology, protect these key positions.

Commonly used to wearing silicon vertical through hole (TSV) as interconnect architecture in the MEMS encapsulation technology, advantage is: thus improve packaging density, the shortening interconnect length reduces loss.

Making the TSV structure has many diverse ways, is " from bottom to top " electro-plating method (Bottom-to-Top electroplating method) than more efficient, method commonly used wherein.Its practice is: (1) is used dry etching technology to carve silicon chip and is obtained through-hole structure, (2) at silicon chip back spatter plating seed layer, (3) electroplate the silicon chip back side, utilize sedimentary metal level to block through hole, (4) electroplate from the front of silicon chip, through hole is realized metallization with " from bottom to top ".

The advantage of this method is simple efficient; The TSV inside of producing does not almost have the cavity, is of high quality.

Yet the various rack plating systems and the useless and suitable plating suspension member of " from bottom to top " electro-plating method (Bottom-to-Top electroplating method) that regrettably are usually used in semiconductor technology at present.Common suspension member structure as shown in Figure 1, its major portion is that Z1 and Z2:Z1 are the hanger main bodys that high-intensity acidproof plastics are done, shape is as a tennis racket; Z2 is the piece of stainless steel that is positioned at the terminal back side of Z1 part, and it makes suspension member can hang over the plating tank sidewall, and links to each other with negative electrode when electroplating.B1, B2, B3, B4, B5, B6, B7, B8 are the stainless steel bolts that is fixed on the Z1, Z2 realizes conducting by two other stainless steel bolt F1, F2 and the copper wire K1 that is wrapped on all bolts, T1, T2, four metal pins of T3, T4 are drawn from K1, they when electroplating fixedly silicon chip and realize silicon chip positive with being electrically connected of negative electrode.As seen this suspension member is applicable to the plating of usual way, and the face that promptly deposits Seed Layer is electroplated face exactly; For " from bottom to top " electro-plating method, Seed Layer overleaf and plating face is positive, this plating suspension member is just inapplicable, four pins can't electrically contact with the Seed Layer at the back side when having fixed silicon chip, electroplate and also just can't carry out.

Though, can be used in and twine the flexible metal filament on four pins, make this traditional plating suspension member be applicable to " from bottom to top " TSV electro-plating method around the method that contacts with Seed Layer to the silicon chip back side, but this way has two shortcomings: (1) is because very thin (otherwise the silicon slice placed injustice of wire, frangible), electrically contact badly, it is galvanized chronic to finish TSV; With 20 micron pore size, 200 microns long TSV are example, finish the electroplating time of metallization needs more than 20 hours of whole through hole; (2) electroplating process makes wire stick on the silicon chip, is difficult for removing.

The applicant attempts to carry out structural improvement on the basis of existing common suspension member structure, provides a kind of and is applicable to that " from bottom to top " electro-plating method prepares the plating suspension member of TSV.

Summary of the invention

In order to make electroplating device and " from bottom to top " TSV electro-plating method adapt, the present invention proposes and a kind ofly be applicable to that electro-plating method is made from bottom to top and wear the employed plating suspension member of silicon vertical through hole.

Plating suspension member structure provided by the invention as shown in Figure 2, the constructional feature of described plating suspension member is:

(1) agent structure 1 be shaped as the square tennis racket, the main part of racket for around be the square of fillet, there is circular depressed in central authorities, and six perforates are arranged all around, are used to place bolt; The shank of racket is a rectangle;

(2) poly (methyl methacrylate) plate 91 of use high strength, acid corrosion-resistant, the sheet rubber 92 of acid corrosion-resistant is pushed down silicon chip 41, by six 81 on bolt poly (methyl methacrylate) plate, sheet rubber and silicon chip 41 is fixed on successively on the main part of agent structure 1 and prevents that electroplate liquid from contacting the back side of silicon chip 41;

(3) will approach copper paper 42 and be laid in silicon chip 41 back sides, electrically contact, touch mutually with thin copper paper 42 by copper wire 31,32 with the Seed Layer at silicon chip 41 back sides; Copper wire 31,32 is electrically connected with the piece of stainless steel 2 at agent structure 1 back side by

bolt

71,72; Piece of stainless steel 2 is connected with the electroplating system negative electrode during plating, thereby realizes being electrically connected of silicon chip and negative electrode; Thin copper paper 42 is the meeting metal refining when electroplating, and can change often to guarantee its suitability; Copper wire 31,32 is positioned at the rectangle shank of racket;

(4) central circular depressed of the main part of agent structure 1 is used to place silicon chip; All there is round hole in the central authorities of poly (methyl methacrylate) plate and sheet rubber, and the diameter in hole is slightly less than the diameter of main part central circular hole shape depression.

The whole suspension member that assembles as shown in Figure 3.Electrical contact performance excellence when this suspension member is electroplated, equally with 20 micron pore size, 200 microns long TSV are example, under identical electroplating parameter, the metallization of using plating suspension member provided by the invention to finish whole through hole only needs the electroplating time about 6 hours.

Description of drawings

Fig. 1 is common suspension member synoptic diagram;

Fig. 2 is the STRUCTURE DECOMPOSITION synoptic diagram of suspension member provided by the invention;

Fig. 3 is the synoptic diagram after the assembling of suspension member provided by the invention.

Embodiment

For setting forth substantive distinguishing features of the present invention and obvious improvement, 2 and 3 be further described in conjunction with the accompanying drawings.

(1) material of agent structure 1 is high-intensity acidproof plastics, and shape is as a square tennis racket; Main part is 14cm * 14cm, and fillet radius is the square of 2cm all around, and central authorities have the circular depressed of diameter 10.24cm (4 cun) to be used to place 4 cun silicon chips, and the perforate of six diameter 0.8cm is arranged all around, are used to place bolt; Shank partly is the rectangle of 3.5cm * 20cm; The thickness of agent structure 1 is 1.5-2cm;

(2) structure 2 materials are stainless steel, are positioned at 1 the back side, connect the electroplating system negative electrode as the extension angle of suspension member and when electroplating, and thickness is 1.5-2cm;

(3) 91 is the poly (methyl methacrylate) plate of high strength, acid corrosion-resistant, and there is the round hole of diameter 9.8cm in central authorities; 92 is the rubber of acid corrosion-resistant, and also there is the round hole of diameter 9.8cm in central authorities; They are used for fixing silicon chip and prevent electroplate liquid contact silicon chip back;

(4) 81 is top end diameter 1.8cm, and the T-shape stainless steel bolt of bottom diameter 0.8cm is used for 91,92 stuck-at-s;

(5)

stainless steel bolt

71,72 is used for parts 2 are fixed on agent structure 1 back side;

(6) copper wire 31,32 is electrically connected with the piece of stainless steel 2 at agent structure 1 back side by

bolt

71,72;

Also use thin copper paper 42 shown in Figure 2 when (7) electroplating, thin copper paper 42 is laid in silicon chip 41 back sides, electrically contacts with the Seed Layer at silicon chip 41 back sides, touch mutually with thin copper paper 42 by copper wire 31,32, thin copper paper thickness at 0.1mm-0.5mm, should not be too thick, otherwise the applying between influence and the silicon chip; Copper wire 31,32 is electrically connected with the piece of stainless steel 2 at agent structure 1 back side by

bolt

71,72; Piece of stainless steel 2 is connected with the electroplating system negative electrode, thereby realizes being electrically connected of silicon chip and electroplating system negative electrode.

Obviously, more than shown in size only be a kind of possible selection, the size shown in being not limited only to during actual the use is as long as the similar Fig. 2 of shape or Fig. 3 of suspension member all belong within protection scope of the present invention.

Claims

1. a plating suspension member that is applicable to the TSV of electro-plating method making from bottom to top comprises agent structure (1) and piece of stainless steel (2), it is characterized in that:

(a) agent structure (1) be shaped as the square tennis racket, the main part of racket for around be the square of fillet, there is circular depressed in central authorities, and six perforates are arranged all around, are used to place bolt; The shank of racket is a rectangle;

(b) pass through bolt (81) successively with poly (methyl methacrylate) plate (91), sheet rubber (92) and silicon chip (41), be fixed on the main part of agent structure (1);

(c) Bao Tongzhi (42) is laid in silicon chip (41) back side, electrically contacts, touch mutually with thin copper paper by copper wire (31), (32) with the Seed Layer at silicon chip (41) back side; Copper wire (31), (32) are electrically connected with the piece of stainless steel (2) at agent structure (1) back side by bolt (71), (72).

2. by the described plating suspension member of claim 1, it is characterized in that the bolt described in the agent structure is a T type stainless steel bolt.

3. by the described plating suspension member of claim 1, it is characterized in that described thin copper paper thickness is 0.1-0.5mm.

4. by the described plating suspension member of claim 1, it is characterized in that the central circular depressed of the main part of agent structure (1) is used to place silicon chip; All there is round hole in the central authorities of poly (methyl methacrylate) plate and sheet rubber, and the diameter in hole is slightly less than the diameter of main part central circular hole shape depression.

5. by the described plating suspension member of claim 1, the thickness that it is characterized in that piece of stainless steel is 1.5-2cm; The thickness of agent structure is 1.5-2cm.

6. by the described plating suspension member of claim 1, it is characterized in that silicon chip is connected enforcement by piece of stainless steel (2) with the electroplating system negative electrode with the electrical connection of electroplating system negative electrode.