CN2837881Y

CN2837881Y - Hot press ram for packaging of drive chip for LCD module

Info

Publication number: CN2837881Y
Application number: CN 200520036179
Authority: CN
Inventors: 何志奇; 陈学刚; 巫后云; 欧向阳
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2005-11-14
Filing date: 2005-11-14
Publication date: 2006-11-15
Anticipated expiration: 2015-11-14

Abstract

The utility model discloses a hot press head for the packaging of a drive chip for an LCD module, which comprises a main press head for carrying out hot press to the drive chip onto a transparent basal plate through an anisotropic conduction film, wherein the end surface of the main press head, which is close to a residual edge of the anisotropic conduction film, is provided with a subsidiary press head for the hot press of the residual edge of the anisotropic conduction film. The hot press head structure of the utility model can assure the total solidification of an entire strip of anisotropic conduction film which is pasted and attached to the basal plate, the connection force of the drive chip and the basal plate can be effectively enhanced, and the packaging quality of the chip can be enhanced; on the other hand, the total solidification of an ACF adhesive layer can prevent the ACF adhesive layer from absorbing water vapor in the environment and causing the corrosion of an ITO electrode.

Description

The thermal head that is used for the encapsulation of LCD MODULE chip for driving

[technical field]

The utility model relates to a kind of thermal head structure, relates in particular to a kind of chip for driving to be received the thermal head on the LCDs module with COG (chip on glass) mode hot pressing.

[background technology]

LCD (LCD) compare with cathode ray tube (CRT) have low driving voltage, low-power consumption, low radiation, the capacity of display reach advantages such as lightening greatly, be widely used in various audio-visual devices and the communication product, the packaged type of its chip for driving develops into COG of today (Chip on Glass) and COF packaged types such as (Chip on Film) from traditional COB (Chip on Board), TAB (Tape Automated Bonding) along with the demand for development of thin space and high image quality.

The COG packaged type normally attaches one deck anisotropic conductive film ACF (Anisotropic Conductive Film) earlier on the glass substrate of LCD, by locating device chip for driving (also abbreviating drive IC as) is placed on the ACF, the reusable heat pressure head carries out hot pressing to drive IC, make the ACF full solidification, so just drive IC and glass substrate have been linked together, and realized the conducting of ITO electrode on pin on the drive IC and the glass substrate by the conducting particles among the ACF.In the above-mentioned processing procedure, consider the accuracy of machine, ACF attaches length and drive IC length and not quite identical, usually the ACF length that attaches exceeds 1-2mm than drive IC length, as shown in Figure 2, so after hot-press solidifying, will respectively have the ACF of 0.5-1mm length to expose in air at the drive IC two ends, be designated as surplus limit 31 of ACF and the surplus limit 32 of ACF respectively, and the ACF that is between chip for driving 20 and the glass substrate 10 is designated as ACF intermediate gelatine layer 33.The thermal head that is adopted in existing C OG packaged type is a rectangular structure, as thermal head among Fig. 1 20, in the thermo-compressed process, thermal head overlays on chip for driving 20, its temperature and pressure is delivered to ACF intermediate gelatine layer 33 by chip for driving 20, the heat on surplus limit 31 of ACF and the surplus limit 32 of ACF then passes over by ACF intermediate gelatine layer 33, directly contact with air with the surplus limit 32 of ACF because of the surplus limit 31 of ACF again, must cause scattering and disappearing of heat, so the temperature on surplus limit 31 of ACF and the surplus limit 32 of ACF is more much lower than ACF intermediate gelatine layer 33, thereby do not reach its best curing temperature, so the state of cure deficiency on surplus limit 31 of ACF and the surplus limit 32 of ACF.State of cure is not enough can to cause following bad phenomenon: 1) the surplus limit of surplus limit 31 of chip for driving 20 ends A CF and ACF 32 bonding force deficiencies, and chip for driving 20 is peeled off from glass substrate 10 easily, and chip for driving 20 also is damaged with the electric conductivity of ITO electrode.2) because of the surplus limit 31 of ACF and the surplus limit 32 of ACF full solidification not, the aqueous vapor in the absorbing environmental causes ito glass substrate 10 circuits easily to corrode easily.

[summary of the invention]

Fundamental purpose of the present utility model is exactly in order to solve problems of the prior art, a kind of thermal head that is used for the encapsulation of LCD MODULE chip for driving is provided, in the time of on the glass substrate that chip for driving is hot-pressed onto LCD MODULE, can make the various piece of anisotropic conductive film all obtain full solidification and then improve the thermo-compressed quality.

For achieving the above object, a kind of thermal head that is used for the encapsulation of LCD MODULE chip for driving that the utility model proposes, comprise being used for chip for driving is hot-pressed onto main pressure head on the transparency carrier by anisotropic conductive film, be provided with the secondary pressure head that is used for the surplus limit of hot pressing anisotropic conductive film with the close main pressure head end face in the surplus limit of anisotropic conductive film.

Described secondary pressure head is two, lays respectively at the two ends of main pressure head and with respect to main pressure head symmetry.

Described main pressure head and secondary pressure head are integral structure, and the longitudinal cross-section of the assembly of described main pressure head and secondary pressure head is shaped as down " U " shape.

Preferably, the described main pressure head length that is clipped in two parts between the secondary pressure head is greater than by the length of hot pressing chip for driving.The height of described secondary pressure head is less than by the thickness of hot pressing chip for driving.

The beneficial effects of the utility model are: the thermal head of this programme is provided with secondary pressure head at main pressure head two ends, when carrying out the pressing operation, the main pressure head of thermal head presses to chip for driving on the transparency carrier of LCD MODULE by an anisotropic conductive film, with the secondary pressure head that the two ends of main pressure head closely contact the surplus limit of anisotropic conductive film (being the exposed anisotropic conductive film ACF in chip for driving two ends) heated, make its full solidification.The thermal head structure of this programme can guarantee to be attached at the whole piece anisotropic conductive film full solidification on the substrate, can effectively improve the power that is connected of chip for driving and substrate, has improved the Chip Packaging quality.On the other hand, ACF glue-line full solidification can prevent the aqueous vapor in its absorbing environmental and cause the ITO electrode corrosion.

Feature of the present utility model and advantage will be elaborated in conjunction with the accompanying drawings by embodiment.

[description of drawings]

Fig. 1 is existing thermal head synoptic diagram;

Fig. 2 is the synoptic diagram that utilizes existing thermal head hot pressing chip for driving;

Fig. 3 is the thermal head structural representation of a kind of embodiment of the present utility model;

Fig. 4 is the longitdinal cross-section diagram of Fig. 3;

Fig. 5 is the synoptic diagram that utilizes thermal head hot pressing chip for driving of the present utility model.

[embodiment]

As shown in Figure 3, be provided with the secondary pressure head 501,502 of two rectangles at original straight main pressure head 500 two ends, and two secondary pressure heads are in full accord, with respect to main pressure head 500 symmetries.Its hot pressing mode as shown in Figure 5, main pressure head 500 presses to chip for driving 200 on the transparency carrier 100 (being generally glass substrate) of LCD MODULE by anisotropic conductive film 300, anisotropic conductive film intermediate gelatine layer (ACF intermediate gelatine layer) 303 heating below 500 pairs of chip for driving of main pressure head 200 are solidified ACF intermediate gelatine layer 303 chip for driving 200 are welded on the substrate 100.The surplus limit of anisotropic conductive film (the surplus limit of ACF) 301,302 heating that 501,502 pairs of chip for driving 200 two ends of two secondary pressure heads are exposed solidify the surplus limit 301,302 of ACF, as shown in Figure 5.

Wherein, the main pressure head of thermal head and two secondary pressure heads use same material to be combined into an integral body by die casting, and the longitudinal cross-section is shaped as down " U " shape, as shown in Figure 4.

Wherein, main pressure head 500 is clipped in the length of two parts between the secondary pressure head 501,502 greater than by the length of hot pressing chip for driving 200, preferably is slightly larger than by the length of hot pressing chip for driving 200.In the pressing process, there is a small spaces 400 in the inboard of the two ends of chip for driving and two secondary pressure heads, avoids secondary pressure head contact chip for driving two ends to damage.

Wherein, the height of two secondary pressure heads 501,502 preferably is slightly less than by the thickness of hot pressing chip for driving 200 less than by the thickness of hot pressing chip for driving 200.In the pressing process, two secondary pressure head 501,502 lower surfaces just touch on the exposed surplus limit 301,302 of anisotropic conductive film, chip for driving 200 two ends, it are not caused extruding.

During hot pressing, thermal head adopts the heated at constant temperature mode, and heat is directly delivered on main pressure head and the secondary pressure head, pressure head each several part temperature constant in the production run.

For characteristics of the present invention and advantage thereof better are described, we adopt following preferred embodiment and comparative example to be described.

Two identical face glasss 10 and 100 are provided, two identical chip for driving 20 and 200, face glass 10 and 100 is overlayed anisotropic conductive film ACF30 and ACF300 respectively behind cleaning-drying, ACF30 is in full accord in face glass 10 positions and the position of ACF300 on face glass 100, the length of ACF30 and ACF300 is in full accord, and the length of ACF30 and ACF300 is than chip for driving 20 and 200 long 2mm.

Under the accurate contraposition of COG equipment, chip for driving 20 and 200 is pressed in the middle of ACF30 and ACF300 respectively in advance, so respectively have the anisotropic conductive film of 1mm to expose in air at the two ends of chip for driving 20 and 200, we are designated as the surplus limit 31 of ACF, the surplus limit 32 of ACF and the surplus limit 301 of ACF, the surplus limit 302 of ACF to them respectively, and we are designated as ACF intermediate gelatine layer 33, ACF intermediate gelatine layer 303 to the ACF that is between chip for driving IC and the face glass.

We carry out crimping to above-mentioned chip for driving 20 and 200 at last, in two steps:

The first step, the crimping of chip for driving 20.Adopt the main pressure head 50 of prior art, as shown in Figure 2, when the pressure head flatness is adjusted to the best, begin main the pressure, main pressure head 50 moves vertically downward, until overlaying on chip for driving 20, and keeps 10s, respectively the surplus limit 31 of ACF, the surplus limit 32 of ACF, ACF intermediate gelatine layer 33 are carried out temperature test then, its result is respectively 151 ℃, 150 ℃, 190 ℃.And the ACF Best Curing that is adopted is temperature T=190 ± 5 ℃, time t=10s.

In second step, the main of chip for driving 200 pressed.Adopt the thermal head of this programme, as shown in Figure 5, when main pressure head 500 flatness and aligning accuracy are adjusted to the best, begin main the pressure, main pressure head 500 moves vertically downward, overlay on chip for driving 200 until the lower plane 503 that is clipped in the main pressure head part between two secondary pressure heads 502, apply suitable pressure to chip for driving 200, and kept 10 seconds, because the length on plane 503 is than the long slightly 10um of chip for driving 200, so chip for driving 200 two ends and secondary pressure head 501,502 all have the space of 5um, have avoided secondary pressure head 501, the injury that cause at 502 contact chip for driving, 200 two ends.When main pressure head overlayed chip for driving 200, secondary pressure head 501,502 also just contacted the surplus limit 301 of ACF, the surplus limit 302 of ACF.Because the height of secondary pressure head 501 and secondary pressure head 502 is slightly less than the thickness of chip for driving 200, so do not exerted pressure in the surplus limit 301 of ACF, the surplus limit 302 of ACF, only transmit heat to them, promote their curing.Equally, also respectively the surplus limit 301 of ACF, the surplus limit 302 of ACF, ACF intermediate gelatine layer 303 are carried out temperature test, its result is respectively 190 ℃, 192 ℃, 191 ℃.

Find from test result: adopt existing thermal head can only make the anisotropic conductive film between the face glass that is in chip for driving reach good solidification effect, do not reach full solidification and be in the anisotropic conductive film that the chip for driving two ends expose at air, so the ACF bonding force of this part is not corroded by force and easily, be easy to cause the generation of the bad phenomenon such as corrosion of ITO electrode.And can make whole piece ACF reach good solidification effect with this programme, above-mentioned bad phenomenon just is difficult to take place.

Claims

1. one kind is used for the thermal head that the LCD MODULE chip for driving encapsulates, comprise being used for chip for driving is hot-pressed onto main pressure head on the transparency carrier by anisotropic conductive film, it is characterized in that: be provided with the secondary pressure head that is used for the surplus limit of hot pressing anisotropic conductive film with the close main pressure head end face in the surplus limit of anisotropic conductive film.

2. thermal head as claimed in claim 1 is characterized in that: described secondary pressure head is two, lays respectively at the two ends of main pressure head and with respect to main pressure head symmetry.

3. thermal head as claimed in claim 2 is characterized in that: described main pressure head and secondary pressure head are integral structure, and the longitudinal cross-section of the assembly of described main pressure head and secondary pressure head is shaped as down " U " shape.

4. as claim 2 or 3 described thermal heads, it is characterized in that: the length that described main pressure head is clipped in two parts between the secondary pressure head is greater than by the length of hot pressing chip for driving.

5. as claim 2 or 3 described thermal heads, it is characterized in that: the height of described secondary pressure head is less than by the thickness of hot pressing chip for driving.

6. thermal head as claimed in claim 4 is characterized in that: the height of described secondary pressure head is less than by the thickness of hot pressing chip for driving.