CN1622303A

CN1622303A - Wire rack free wafer packaging process

Info

Publication number: CN1622303A
Application number: CN 200410011361
Authority: CN
Inventors: 资重兴
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-12-17
Filing date: 2004-12-17
Publication date: 2005-06-01

Abstract

The chip packing process without wire frame includes the following steps: A) coating adhesive to the signal joint surface of bare chip while forming inner connecting windows to expose the signal joints; B) covering the fixed layer with metal wires and outer connecting windows to the adhesive layer to make the metal wires possess outer ends extending to the outer connecting windows and inner ends connected electrically to the signal joints of the bare chip; C) setting metal conductors to the outer connecting windows of the fixed layer and connecting the metal conductors with the outer ends of the metal wires electrically while exposing the outer connecting windows; and D) cutting out excessive adhesive layer and fixed layer material and forming single chip package.

Description

The wafer encapsulation procedure of no lead frame

Technical field

The present invention relates to a kind of wafer encapsulation procedure that does not have lead frame, particularly a kind ofly exempt from naked wafer to be had and externally to be electrically conducted function, and can be assembled in the wafer encapsulation procedure that equipment such as circuit board is used with lead frame.

Background technology

Traditional chip package structure as shown in Figure 7, it has a metal matter lead frame 10, this lead frame 10 is by both sides or adopts all around and stamp out plural sheet pin 101 and arranged formation, each pin 101 lower ends dash and are provided with a projection 102, use these projection 102 end faces 103 as external conducting position, and pin 101 tops of lead frame 10 are covered with a stickiness adhesive tape 20, this stickiness adhesive tape 20 is fixed with a naked wafer 30, by this, and be provided with one in this naked wafer 30 and 101 of each pins and constitute the metal wire 40 that electrically connects, and after metal wire 40 connections are finished, implementing an insulating properties adhesive body 50 seals up around the naked wafer 30 and lead frame 10 bottom surfaces, expose the lower surface 103 of only reserving described pin 101, can form to electrically connect with the circuit board assembling to use.

The processing procedure of above-mentioned known chip package structure generally includes following steps:

(A) wafer cutting: with the wafer cutting and separating is plural naked wafer 30; (B) weldering is brilliant: the naked wafer 30 that cutting is finished is placed on above the lead frame 10, and it is fixing to use stickiness adhesive tape 20 to be sticked together; (C) routing: pin 101 the inners that the signal contact on the naked wafer 30 are connected to lead frame 10 with metal wire 40; (D) sealing: promptly implement an insulating properties adhesive body 50 and seal up around the naked wafer 30 and lead frame 10; (E) cut single moulding:, and be shaped to independently encapsulated wafer promptly with the machine material removal that lead frame 10 and adhesive body 50 is unnecessary.

In the above-mentioned wafer encapsulation procedure, this lead frame needs to use the sheet metal punch forming in addition, and the difficulty of stamping technology is precision control; Secondly, after known these metal wire 40 welding are finished, must make through adhesive body 50 sealings, it injects half adhesive body 50 processes of melting, damage metal wire 40 or its signal contact situation often taking place, thereby produce many faulty materials, must use expensive instrument to survey when subsequent detection; Known wafer encapsulation procedure is unfavorable for the reduction of packaging cost and QC cost.

Summary of the invention

The objective of the invention is to solve in the known wafer encapsulation procedure and easily to produce faulty materials and cause the high problem of manufacturing cost, and a kind of wafer encapsulation procedure that overcomes the no lead frame of above-mentioned shortcoming is provided.

The present invention includes following steps:

(A) cover glue: cover one deck at this face of signal contact of naked wafer and follow glue-line, then glue-line be provided with corresponding naked wafer signal contact in connect window, make naked wafer signal contact expose via connecing window in the then glue-line;

(B) last slice: the fixed bed that inner face is provided with multiple metal wire covers in following glue-line, this fixed bed is provided with the external window of corresponding circuits plate signal contact, make the plain conductor outer end extend external window place, and the inner signal contact with naked wafer of plain conductor constitute electric connection;

(C) implantable conductive body:, make this metallic conductor and plain conductor outer end constitute and electrically connect, and be exposed to external window place at the external window implanted metal electric conductor of fixed bed;

(D) cut single moulding:, and form single encapsulated wafer with unnecessary then glue-line and fixed bed material removal.

By this, form naked wafer signal contact face and be provided with the then encapsulated wafer of glue-line, multiple metal wire and a fixed bed in regular turn, making plain conductor the inner connect window in extending contacts with naked wafer signal contact, contact with electric conductor in the window and the outer end extends external window, can utilize equipment such as this electric conductor and circuit board to electrically connect.

Description of drawings

Fig. 1 is a schematic flow sheet of the present invention.

Fig. 2 is vertical cross-sectional schematic of the packaged wafer of the present invention.

Fig. 3 is the horizontal cross-sectional schematic of the packaged wafer of the present invention.

Fig. 4 is the encapsulating structure decomposing schematic representation after the present invention's naked wafer is cut list.

Fig. 5 is the encapsulating structure decomposing schematic representation after the present invention's plural naked wafer is cut list.

Fig. 6 for the present invention's naked wafer in the encapsulating structure decomposing schematic representation of wafer state.

Fig. 7 is the cross-sectional schematic of known chip package structure.

Embodiment

See also Fig. 1, Fig. 2, shown in Figure 3, the made chip package structure of the present invention by signal contact 11 these faces of a naked wafer 1 be provided with in regular turn one then glue-line 2, multiple metal wire 3 and a fixed bed 4 formed, step of the present invention is as follows:

(A) cover glue: consult Fig. 1, Fig. 2, shown in Figure 3, cover one deck at signal contact 11 these faces of naked wafer 1 and follow glue-line 2, then glue-line 2 be provided with corresponding naked wafer 1 signal contact 11 in connect window 21, as shown in Figure 4, make naked wafer 1 signal contact 11 expose via connecing window 21 in the then glue-line 2; Wherein, the described then step of glue-line 2 that covers, be to cut the enforcement out of the ordinary of single back in this naked wafer 1, as shown in Figure 4, or can in this naked wafer 1 cut single after, with several naked wafers 1 be covered on continuously a rubber belt material then implement to finish on the glue-line 2, as shown in Figure 5, or can before cutting list, naked wafer 1 promptly when wafer 10 states, cover described then glue-line 2 in advance, as shown in Figure 6; In addition, then glue-line 2 constituted modes comprise, but the mode that pastes of application of tape material, or realize in the mode of being coated with of materials such as resin, silica gel, its mode of being coated with is screen print process or dotting glue method or thin film manufacture process method or model shaping etc., and can make this follow glue-line 2 and solidify through the overbaking program.

(B) last slice: consult Fig. 1, Fig. 2, shown in Figure 3, the fixed bed 4 that inner face is provided with multiple metal wire 3 covers in following glue-line 2 outsides, this fixed bed 4 is provided with the external window 41 of corresponding circuits plate signal contact in advance, make the outer end of plain conductor 3 extend external window 41 places, and the signal contact 11 of plain conductor 3 inner 31 and naked wafer 1 constitute electric connection; Wherein, the described step that covers fixed bed 4, be to cut single state in this naked wafer 1 distinctly to implement, as shown in Figure 4, or can after several naked wafers 1 are covered on the then glue-line 2 of a rubber belt material continuously, implement to finish, as shown in Figure 5, or can be before naked wafer 1 is cut singly, promptly after covering described then glue-line 2, wafer 10 states implement to finish, as shown in Figure 6; In addition, these fixed bed 4 constituted modes comprise and can be that a resin molding inner face is glutinous to be provided with multiple metal wire 3, make this resin molding be attached to then glue-line 2 outsides again, thereafter and can this fixed bed 4 be solidified through the overbaking program.

(C) implantable conductive body: consult Fig. 2, Fig. 3, shown in Figure 4, external window 41 implanted metal electric conductors 5 at fixed bed 4, make this metallic conductor 5 and the outer end of plain conductor 3 constitute electric connection, and make metallic conductor 5 be exposed to external window 41 places, can electrically connect with equipment such as circuit boards; Wherein, the constituted mode of described metallic conductor 5 is for implanting the tin ball or injecting the tin cream mode and realize.

(D) cut single moulding:, and form an independently single individually encapsulated wafer with unnecessary then glue-line 2 and fixed bed 4 material removals.

Mat above-mentioned (A) covers glue, (B) last slice, (C) implantable conductive body, (D) cuts single forming step, promptly form naked wafer 1 signal contact face 11 and be provided with the then encapsulated wafer of glue-line 2, multiple metal wire 3 and a fixed bed 4 in regular turn, as Fig. 2, shown in Figure 3, making plain conductor 3 the inners 31 connect window 21 in extending contacts with naked wafer 1 signal contact 11, and plain conductor 3 outer ends 32 extend external window 41 and contact with electric conductor 5 in the window, can utilize equipment such as this electric conductor 5 and circuit board to electrically connect.

See also shown in Figure 4, fixed bed 4 also can in correspondence follow glue-line 2 in meet window 21 places and connect window 42 in offering in advance, can in this, connect by this and implement above-mentioned (C) implantable conductive body step in the window 42, so that the inner 31 of multiple metal wire 3 constitutes firm electric connection state with naked wafer 1 signal contact 11.

The present invention has exempted traditional conducting wire frame structure, so can avoid the punching press of conventional wires frame, cut etc. that quality is difficult to shortcomings such as accurately controls in the processing procedure, has reduced the material cost and the QC cost of use lead frame; And because of wafer encapsulation procedure of the present invention does not use lead frame, it is frivolous that the overall chip encapsulating structure is more attained, and meeting electronic product exquisitenessization designer trends at present, and promotes naked wafer 1 output that same wafer can cut out.Secondly, the present invention's plain conductor 3 can be attached to fixed bed 4 in advance, make fixed bed 4 be covered on then glue-line 2 again, make multiple metal wire 3 fixing, this multiple metal wire 3 needn't be born the pressure of traditional adhesive body perfusion and impulsive force etc. in processing procedure, can not only improve the infringement that the adhesive body canned program is caused behind traditional routing, further effectively promote the yields of chip assembly, and can therefore simplify wafer encapsulation procedure, promptly need not traditional routing step, with effective reduction packaging cost and follow-up detection QC cost.

Claims

1, a kind of wafer encapsulation procedure that does not have lead frame, this processing procedure may further comprise the steps:

(D) cut single moulding:, and form single encapsulated wafer with unnecessary then glue-line and fixed bed material removal;

2, according to the described a kind of wafer encapsulation procedure that does not have lead frame of claim 1, it is characterized in that: the described one deck that covers is followed the glue-line step, be to cut out of the ordinary enforcement the in single back in this naked wafer to finish, or can be after this naked wafer be cut list, several naked wafers are covered on then implement to finish on the glue-line, or can cut wafer state before single at naked wafer and cover enforcement in advance and finish.

3, according to the described a kind of wafer encapsulation procedure that does not have lead frame of claim 1, it is characterized in that: the described one deck that covers is followed the glue-line step, is the mode that pastes of rubber belt material, or realizes in the mode of being coated with of resin, silica gel material,

4, according to the described a kind of wafer encapsulation procedure that does not have lead frame of claim 3, it is characterized in that: the described mode of being coated with is screen print process or dotting glue method or thin film manufacture process method or model shaping.

5, according to the described a kind of wafer encapsulation procedure that does not have lead frame of claim 1, it is characterized in that: described fixed bed covers in the step of following the glue-line outside, be to cut out of the ordinary enforcement of single state in this naked wafer to finish, or can paste then in several naked wafers and implements to finish after the glue-line, or can cut wafer state before single at naked wafer and cover and describedly follow glue-line enforcement afterwards and finish.

6, according to the described a kind of wafer encapsulation procedure that does not have lead frame of claim 5, it is characterized in that: described fixed bed covers in the step of following the glue-line outside, being that a resin molding inner face is glutinous is provided with multiple metal wire, makes this resin molding be attached to then glue-line outside again.

7, according to the described a kind of wafer encapsulation procedure that does not have lead frame of claim 1, it is characterized in that: the constituted mode of described metallic conductor is for implanting the tin ball or injecting the tin cream mode and realize.

8, according to the described a kind of wafer encapsulation procedure that does not have lead frame of claim 1, it is characterized in that: described (A) covers glue and (B) after last slice step, respectively through the overbaking program.