TWI594888B - Method of debonding flexible substrate - Google Patents

Description

Method of peeling flexible substrate

The present invention relates to a method of processing a substrate, and more particularly to a method of stripping a flexible substrate.

When fabricating a flexible device, a flexible substrate must be used to carry the component. In order to fabricate the component on a flexible substrate, the flexible substrate is first formed on a rigid carrier substrate to provide suitable support using the carrier substrate. After the component is fabricated, the flexible substrate is removed from the carrier substrate. At present, methods for stripping flexible substrates include mechanical peeling, chemical processing, laser or ultraviolet light processing, among which mechanical peeling technology is favored because it has the advantages of not damaging the surface of the flexible substrate, low equipment cost, and high speed. Attention.

The mechanical peeling technique mainly uses a gas communication line to discharge the gas in the connection assembly to generate an adsorption force. The adsorption force must be capable of resisting the release force of the flexible substrate to remove the flexible substrate from the carrier substrate. The denser the component structure on the flexible substrate or the stronger the material of the component mounting, the stronger the release force. In the case where there is a difference in the density of the regions of the elements, there is a local difference in the release force of the flexible substrate.

Taking the flexible display panel as an example, the joint area of the flexible display panel is an area where the peripheral traces are collected, and thus has a large release force. In the process of peeling off the flexible display panel, the joint region requires a large suction force to be peeled off. When peeling off from the side of the flexible display panel that is away from the joint region, the flexible display panel and the carrier substrate may not be separated due to insufficient adsorption force when the joint region is reached. If the adsorption force greater than the maximum release force of the flexible display panel is used to adsorb the entire substrate, the area of the flexible display panel may be excessively pulled, and the components in the area may be damaged. . In view of the above, the adsorption force of the flexible substrate peeling device needs to be able to be changed in response to different release forces to maintain the integrity of the components on the flexible substrate while peeling off the flexible substrate.

The present invention provides a method of peeling off a flexible substrate, which can adjust the adsorption force of the flexible substrate peeling device in response to the difference in the release force. A method for peeling off a flexible substrate according to the present invention comprises: step A, contacting a flexible substrate stripping device with a flexible substrate; and step B, extracting a gas in the flexible substrate stripping device; and step C, determining Whether the shape variable of the deformation portion of the flexible substrate stripping device reaches the preset shape variable, if the preset shape variable is reached, step D is performed, and if the preset shape variable is not reached, step E is performed; step D is raised. The flexible substrate stripping device; in step E, determining whether the total pumping amount reaches the maximum pumping amount, if the maximum pumping amount is not reached, step B and step C are sequentially performed, and if the maximum pumping amount is reached, step F and steps are sequentially performed. G; Step F, pressing down the flexible substrate peeling device; Step G, determining whether the deformation of the deformation portion of the flexible substrate peeling device reaches a preset shape variable, and if the preset shape variable is reached, performing step D, if If the preset shape variable is not reached, step H is performed; in step H, it is determined whether the shape variable of the deformation portion of the flexible substrate peeling device reaches a preset shape variable within a preset time, and if the preset shape variable is reached, In step D, if the preset shape variable is not reached, step I; step I is performed to determine whether the total amount of depression of the flexible substrate stripping device reaches the maximum amount of depression, and if the maximum amount of depression is not reached, Step F and step G are performed. If the maximum amount of depression is reached, step J is performed; and step J is performed to raise the flexible substrate stripping device.

Based on the above, the method of peeling off the flexible substrate of the present invention determines whether the adsorption force is sufficient to resist the release force of the substrate in accordance with the deformation amount of the deformation portion. When the shape variable reaches the preset shape variable, the representative substrate has been peeled off. Conversely, when the shape variable cannot reach the preset shape variable, it means that the adsorption force is insufficient, and the adsorption force can be increased by extracting more gas in the flexible substrate stripping device. Since the method of peeling off the flexible substrate of the present invention can adjust the adsorption force of the flexible substrate peeling device in response to the difference in the release force, it is possible to solve the problem that the process time is delayed due to insufficient adsorption force or the flexible substrate cannot be peeled off. Moreover, it is possible to avoid damage to the element due to excessive adsorption force to adsorb the entire flexible substrate.

The above described features and advantages of the invention will be apparent from the following description.

1A and 1B are flow diagrams respectively illustrating a method of peeling a flexible substrate in accordance with an embodiment of the present invention. 2 and 3 are schematic cross-sectional views showing a substrate peeling system for applying the method of peeling a flexible substrate of FIG. 1A or FIG. 1B, respectively, for showing a relative arrangement relationship between a gap sensor and a flexible substrate peeling device. However, the method of peeling off the flexible substrate of the present invention is not limited to use in the flexible substrate peeling system illustrated in FIGS. 2 and 3.

Referring first to FIG. 2, the flexible substrate stripping system 10 is adapted to strip the flexible substrate SUB, and the flexible substrate stripping system 10 can include a flexible substrate stripping device 12, a carrier substrate 14, a vacuum stage 16, and at least An altimeter 18

The flexible substrate SUB is disposed on the carrier substrate 14. The carrier substrate 14 is, for example, a rigid substrate. The rigid substrate may include a glass substrate, and the flexible substrate may include a plastic substrate, but is not limited thereto. The carrier substrate 14 is disposed on the vacuum stage 16 to provide suitable attachment using the vacuum stage 16.

The flexible substrate stripping device 12 is located on the flexible substrate SUB, and the flexible substrate stripping device 12 can include at least one gas communication line 120, a connection assembly 122, and a height adjustment device 124. One end of the at least one gas communication line 120 is coupled to the connection assembly 122, and the other end of the at least one gas communication line 120 is connectable to a gas source to provide a gas to the connection assembly 122. Alternatively, the other end of the at least one gas communication line 120 can be coupled to an air extraction device to vent gas in the connection assembly 122.

The connection assembly 122 includes a deformation portion DP and an adsorption portion AP. The at least one gas communication line 120 is connected to the deformation portion DP, and the deformation portion DP is located between the at least one gas communication line 120 and the adsorption portion AP. The adsorption portion AP is adapted to adsorb the flexible substrate SUB.

In detail, the deformation portion DP may include a first seal 1221, a first support plate 1222, and a second support plate 1223. The second support plate 1223 is located between the first support plate 1222 and the adsorption portion AP. The first sealing member 1221 connects the first supporting plate 1222 and the second supporting plate 1223, and the first supporting plate 1222, the second supporting plate 1223 and the first sealing member 1221 surround the space R. The space R has a variable volume. The deformation portion DP may further include a first porous material 1224, and the first porous material 1224 is filled into the space R. The first porous material 1224 may include sponge, foam or latex, etc., but is not limited thereto. In another embodiment, the first porous material 1224 may also be omitted and the space R is only filled with gas.

The material of the first sealing member 1221, the first supporting plate 1222, and the second supporting plate 1223 is made of, for example, a gas-tight material. For example, the material of the first sealing member 1221 may include rubber, silicone, PU material or PE film, etc., but is not limited thereto. In addition, the materials of the first support plate 1222 and the second support plate 1223 may include plastics such as polyethylene terephthalate (PET) or polymethylmethacrylate (PMMA).

The first support plate 1222 and the second support plate 1223 respectively have through holes for allowing the gas in the at least one gas communication line 120, the space R, and the adsorption portion AP to circulate. Further, the first support plate 1222 has at least one first through hole T1 corresponding to the at least one gas communication line 120, and the at least one first through hole T1 is connected to the space R and the at least one gas. Line 120. The second support plate 1223 has at least one second through hole T2, and the at least one second through hole T2 connects the space R and the adsorption portion AP.

The adsorption portion AP is disposed on the lower surface SB of the second support plate 1223 and includes a second porous material 1225 and a second seal 1226. The second porous material 1225 and the space R are respectively located on opposite sides of the second support plate 1223, and the at least one second through hole T2 connects the space R and the second porous material 1225. For example, the second porous material 1225 may include a sponge, a foam, a latex, or the like, but is not limited thereto. The average size of the holes H2 of the second porous material 1225 is smaller than the average size of the holes H1 of the first porous material 1224, so that the adsorption portion AP has better stiffness and is less susceptible to deformation. The second seal 1226 is disposed on a side of the second porous material 1225. The material of the second sealing member 1226 is, for example, a gas-tight material. For example, the material of the second sealing member 1226 may include rubber, silicone, PU material or PE film, etc., but is not limited thereto.

A height adjustment device 124 is secured to one side of the connection assembly 122 to adjust the height of the connection assembly 122. Further, the height adjustment device 124 is disposed on the first support plate 1222 , and the at least one gas communication line 120 is connected to the first support plate 1222 , for example, through the height adjustment device 124 .

The at least one altimeter 18 is, for example, a non-contact altimeter, such as an optical altimeter, but is not limited thereto. The altimeter 18 is disposed below the deformation portion DP. The altimeter 18 is adapted to emit the light beam L toward the deformation portion DP and to receive the light beam L' reflected by the deformation portion DP. When the material of the first sealing member 1221 is made of a reflective material, and the material of the second supporting plate 1223 is made of a transparent material, the light beam L emitted by the deformation portion DP passes through the second supporting plate 1223 and is replaced by the first sealing member. The 1221 reflection, reflected light beam L' is received by the altimeter 18 after passing through the second support plate 1223. When the deformation portion DP causes the space R to be compressed due to the pressure difference between the inside and the outside, the second support plate 1223 approaches toward the first support plate 1222, causing the longitudinal distance H between the first seal member 1221 and the altimeter 18 to increase, thereby delaying the altimeter 18 The time at which the beam L' was received. In other words, the amount of time delay in receiving the beam L' from the altimeter 18 can be used to derive the amount of variation in the longitudinal distance H. Since the variation amount of the longitudinal distance H is proportional to the deformation amount of the deformation portion DP, the shape variable of the deformation portion DP can be derived based on the amount of time delay in which the altimeter 18 receives the light beam L'. Alternatively, when the flexible substrate peeling device 12 is depressed, the longitudinal distance H between the first seal 1221 and the altimeter 18 is reduced, thereby reducing the time at which the altimeter 18 receives the light beam L'. Therefore, the amount of time reduction of the light beam L' can be received from the altimeter 18 to push down the amount of depression of the flexible substrate peeling device 12.

It should be noted that the at least one altimeter 18 is not limited to the non-contact altimeter, and the relative arrangement relationship between the at least one altimeter 18 and the flexible substrate stripping device 12 is not limited to the one shown in FIG. 2 . As shown in the substrate stripping system 20 of FIG. 3, the at least one altimeter 28 can also be a contact altimeter, and the at least one altimeter 28 can be embedded in the deformation portion DP through the height adjustment device 124. The at least one altimeter 28 may have a height sensing side element GSE and a wire CW connecting the height sensing side element GSE. The height sensing side element GSE may be located between the first support plate 1222 and the second support plate 1223. When the deformation portion DP is compressed by the internal and external pressure difference, the second support plate 1223 approaches the first support plate 1222, and the height sensing side element GSE generates a signal according to the deformation of the deformation portion DP, and the signal is generated. The analysis process is performed by outputting from the external circuit via the wire CW.

For convenience of explanation, a method of peeling off the flexible substrate will be described below with reference to FIG. 1A and FIG. Referring to FIG. 1A and FIG. 2, the method of peeling off the flexible substrate may include the following steps. First, step A is performed to bring the flexible substrate peeling device 12 into contact with the flexible substrate SUB. The method of bringing the flexible substrate peeling device 12 into contact with the flexible substrate SUB can adjust the height of the connection member 122 by the height adjusting device 124 to bring the adsorption portion AP into contact with the flexible substrate SUB.

Next, step B is performed to extract the gas in the flexible substrate peeling device 12. The extraction amount is a constant value, and after the first gas extraction, the gas pressure in the flexible substrate peeling device 12 is designed to be able to peel off the gas pressure of the region where the release force of the flexible substrate SUB is weak. Further, the amount of extracted gas can be set according to factors such as the material of the flexible substrate SUB itself or the layout of the components on the flexible substrate SUB.

During the evacuation, the gas in the adsorption portion AP is discharged from the second through hole T2, so that the gas pressure in the adsorption portion AP is lower than the external pressure (for example, one atmosphere), and the flexible substrate SUB is adsorbed. After the continuous pumping, the space R of the deformation portion DP is compressed by the internal and external pressure difference, so that the second support plate 1223 approaches the first support plate 1222. When the space R is compressed, an adsorption force that lifts up the flexible substrate SUB is generated. If the adsorption force is greater than the release force of the flexible substrate SUB, the flexible substrate SUB can be peeled off. Conversely, if the adsorption force is less than the release force, the flexible substrate SUB cannot be peeled off.

In order to confirm whether or not the flexible substrate SUB is peeled off, a predetermined shape variable can be set. For example, the preset shape variable falls within the range of 1 mm to 6 mm. When the shape variable reaches the preset shape variable, it means that the flexible substrate SUB has been peeled off. Conversely, when the shape variable cannot reach the preset shape variable, it means that the adsorption force is insufficient, and the gas in the flexible substrate peeling device 12 needs to be extracted again to increase the adsorption force.

After step B, step C can be continued to determine whether the shape variable of the deformation portion DP of the flexible substrate stripping device 12 reaches a preset shape variable. If the preset shape variable is reached, step D is performed, if the preset shape is not reached. For the variable, go to step E. For the method of obtaining the shape variable of the deformation portion DP, reference may be made to the descriptions of the altimeter 18, 28 in FIGS. 2 and 3, and details are not described herein again.

In step C, if the shape variable reaches the preset shape variable, the flexible substrate peeling device 12 can be raised by the height adjusting device 124 (step D) to facilitate removal of the flexible substrate SUB. In the present embodiment, before the flexible substrate SUB is removed from the flexible substrate peeling device 12, the flexible substrate SUB may be attached to the auxiliary film (not shown) (step K). The auxiliary film can be further attached to the flexible substrate peeling device 12 and folded back to the back surface of the flexible substrate peeling device 12 (the surface of the flexible substrate peeling device 12 facing away from the flexible substrate SUB) for subsequent take-up And stripping. The material of the auxiliary film may be a viscous plastic film such as tape, but not limited thereto.

Next, step L is performed to separate the flexible substrate peeling device 12 from the flexible substrate SUB. The method of separating the flexible substrate stripping device 12 from the flexible substrate SUB may include closing the pumping system. In an embodiment, the flexible substrate stripping device 12 may further include an ion gas supply source not shown. An ion gas supply source is coupled to the at least one gas communication line 120. When the flexible substrate peeling device 12 and the flexible substrate SUB are separated, the ion gas supply source can be supplied with ion gas to remove electrostatic adsorption and dust.

After the step L, and before the auxiliary film is removed, the flexible substrate SUB may be bonded to an external line (such as a flexible wiring board) not shown, and the auxiliary film and the flexible substrate SUB may be separated. When the flexible substrate peeling device 12 is separated from the flexible substrate SUB, the flexible substrate SUB is easily stretched or pressed by stress release, causing deformation (such as shape or position change) of the component on the flexible substrate SUB. Or damage. Therefore, by attaching the auxiliary film first, separating the flexible substrate peeling device 12 and the flexible substrate SUB, and first bonding the external wiring and then peeling off the auxiliary film, stress pre-release can be avoided, thereby improving the flexible substrate SUB. The upper element cannot be engaged with the external line due to deformation.

In step C, if the shape variable does not reach the preset shape variable, it is judged whether the total pumping amount reaches the maximum pumping amount (step E), and if the maximum pumping amount is not reached, it may return to step B (pumping step) to The adsorption force of the flexible substrate peeling device 12 is raised, and in step C, it is judged whether or not the flexible substrate SUB is peeled off. If the flexible substrate SUB cannot be peeled off until the maximum pumping amount is reached, the flexible substrate peeling device 12 is first depressed (step F) to increase the airtightness of the flexible substrate peeling device 12 and the flexible substrate SUB. .

Next, it is determined whether the shape variable of the deformation portion DP of the flexible substrate peeling device 12 reaches the preset shape variable (step G), and if the preset shape variable is reached, step D is performed, if the preset shape variable is not reached (representative still If the flexible substrate SUB cannot be peeled off, it is judged whether or not the deformation amount of the deformation portion DP of the flexible substrate peeling device 12 reaches the preset shape variable within the preset time (step H). If the preset shape variable is reached, step D is performed, and if the preset shape variable is not reached, it is judged whether or not the total depression amount of the flexible substrate peeling device 12 reaches the maximum depression amount (step I). If the maximum amount of depression is not reached, steps F and G are sequentially performed, and when the maximum amount of depression is reached, the flexible substrate peeling device 12 is raised (step J).

Further, in the case where there is a problem of air leakage or other equipment, the flexible substrate SUB may not be peeled off even if the pressing step is repeated a plurality of times. Therefore, the stop loss point (preset time) can be set. If the flexible substrate SUB cannot be peeled off (the preset shape variable cannot be reached) within the preset time, the multiple pressing step (step F) and determination can be performed. Step (step G). On the other hand, when the process time reaches the preset time, if the shape variable has not reached the preset shape variable, the flexible substrate stripping device 12 is raised (step J) to check whether it is a gas leak or other equipment problem. . In the step J, the method of raising the flexible substrate peeling device 12 can be referred to step D, and details are not described herein again. The preset time is set to the longest waiting time from the contact of the flexible substrate stripping device 12 with the flexible substrate SUB. The preset time can be adjusted according to parameters such as stiffness, size, and the like of the flexible substrate SUB. For example, the preset time is within 30 seconds from the contact of the flexible substrate stripping device 12 with the flexible substrate SUB, but is not limited thereto.

The method of stripping the flexible substrate may further include other steps or remove some of the steps in FIG. 1A, depending on various needs. For example, before performing step A, a portion of the edge of the flexible substrate SUB may be separated from the carrier substrate 14 in advance to reduce the adsorption force required to peel off the flexible substrate SUB. As a result, the amount of gas to be extracted for peeling off the flexible substrate SUB can be reduced, thereby reducing the thickness at which the space R is compressed. A method of separating a portion of the edge of the flexible substrate SUB from the carrier substrate 14 may include a blow-up pretreatment. For example, a part of the edge of the flexible substrate SUB is blown by a wind knife (not shown), but not limited thereto.

Further, as shown in FIG. 1B, if the total evacuation amount reaches the maximum pumping amount and the flexible substrate SUB cannot be peeled off (step E), the flexible substrate peeling device 12 (step F) can be returned before being able to return to the flexible state. The air pressure in the substrate peeling device 12 (step M). Thus, the component protection on the flexible substrate SUB is preferable. The air pressure in the flexible substrate peeling device 12 is returned to the normal pressure, for example, one atmosphere, but not limited thereto.

After the flexible substrate peeling device 12 is pressed down (step F), the gas in the flexible substrate peeling device 12 can be successively taken out (step N) to peel off the flexible substrate SUB. If the flexible substrate SUB cannot be peeled off after the pumping (step N), it is determined whether the total pumping amount reaches the maximum pumping amount (step O), and if the maximum pumping amount is not reached, the pumping step may be repeated (step N) And the judgment step (step G). If the maximum pumping amount is reached, step H is performed (see if the flexible substrate SUB can be peeled off within a preset time). If the flexible substrate SUB cannot be peeled off after waiting for the preset time, it is judged whether or not the total depression amount of the flexible substrate peeling device 12 reaches the maximum depression amount (step I). If the maximum amount of depression is not reached, step M (recompression) may be performed first, followed by step F (repressing the flexible substrate stripping device 12 again), step N (pumping), and step G (determining Whether the flexible substrate SUB is peeled off). When the maximum amount of depression is reached, the flexible substrate peeling device 12 is raised (step J).

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and any one of ordinary skill in the art can make some changes and refinements without departing from the spirit and scope of the present invention. The scope of the invention is defined by the scope of the appended claims.

10, 20‧‧‧Flexible substrate stripping system
12‧‧‧Flexible substrate stripping device
14‧‧‧Loading substrate
16‧‧‧vacuum stage
18, 28‧‧‧ altimeter
120‧‧‧ gas communication line
122‧‧‧Connecting components
124‧‧‧ Height adjustment device
1221‧‧‧First seal
1222‧‧‧First support plate
1223‧‧‧second support plate
1224‧‧‧First porous material
1225‧‧‧Second porous material
1226‧‧‧Second seal
A, B, C, D, E, F, G, H, I, J, K, L, M, N, O‧ ‧ steps
AP‧‧‧Adsorption Department
CW‧‧‧ wire
DP‧‧‧Deformation Department
GSE‧‧‧ high-sensitivity side components
H‧‧‧Longitudinal distance
H1, H2‧‧‧ holes
L, L'‧‧‧ beams
R‧‧‧ Space
SB‧‧‧ lower surface
SUB‧‧‧flexible substrate
T1‧‧‧ first through hole
T2‧‧‧ second through hole

1A and 1B are flow diagrams respectively illustrating a method of peeling a flexible substrate in accordance with an embodiment of the present invention. 2 and 3 are schematic cross-sectional views of a substrate stripping system using the method of peeling a flexible substrate of FIG. 1A or FIG. 1B, respectively.

A, B, C, D, E, F, G, H, I, J, K, L‧‧‧ steps

Claims (9)

A method for peeling off a flexible substrate, comprising: Step A: contacting a flexible substrate stripping device with the flexible substrate; Step B, extracting gas in the flexible substrate stripping device; Step C, determining the Whether the shape variable of a deformed portion of the flexible substrate stripping device reaches a predetermined shape variable, if the preset shape variable is reached, step D is performed, and if the preset shape variable is not reached, step E is performed; And raising the flexible substrate stripping device; Step E, determining whether the total pumping amount reaches a maximum pumping amount; if the maximum pumping amount is not reached, performing steps B and C sequentially, if the maximum pumping amount is reached, Step F and step G are performed in sequence; step F, pressing the flexible substrate stripping device; step G, determining whether the deformation of the deformation portion of the flexible substrate stripping device reaches the predetermined shape variable, If the preset shape variable is reached, step D is performed. If the preset shape variable is not reached, step H is performed; step H, determining the shape of the deformation portion of the flexible substrate stripping device within a predetermined time Whether the variable To the preset shape variable, if the preset shape variable is reached, step D is performed, and if the preset shape variable is not reached, step I is performed; step I, determining the total amount of depression of the flexible substrate stripping device Whether the maximum amount of depression is reached, if the maximum amount of depression is not reached, step F and step G are sequentially performed, and if the maximum amount of depression is reached, step J is performed; and step J is performed to raise the flexibility. Substrate stripping device. The method of peeling off a flexible substrate according to claim 1, wherein the predetermined shape variable falls within a range of 1 mm to 6 mm. The method of peeling a flexible substrate according to claim 1, wherein the predetermined time is within 30 seconds from the contact of the flexible substrate peeling device with the flexible substrate. The method of peeling off a flexible substrate according to claim 1, wherein after performing step D, further comprising: step K, attaching the flexible substrate with an auxiliary film; and step L, making the flexible The substrate peeling device is separated from the flexible substrate. The method of peeling off a flexible substrate according to claim 4, wherein in the step L, the method of separating the flexible substrate stripping device from the flexible substrate comprises: closing an air extraction system. The method of peeling off a flexible substrate according to claim 5, wherein in the step L, the method of separating the flexible substrate stripping device from the flexible substrate further comprises: providing ion gas to the Flexible substrate peeling device. The method of peeling off a flexible substrate according to claim 1, wherein before performing step A, further comprising: separating a portion of the edge of the flexible substrate from a carrier substrate in advance. The method of peeling off a flexible substrate according to claim 7, wherein the method of separating the portion of the edge of the substrate from the carrier substrate comprises a blow-up pretreatment. The method for peeling off a flexible substrate according to claim 1, wherein after performing step E and before performing step F, the method further comprises: step M, recovering the air pressure in the flexible substrate stripping device, and performing After the step F and before the step G is performed, the method further includes: Step N: extracting the gas in the flexible substrate stripping device, after performing step G and before performing step H, further comprising: step O, determining whether the total pumping amount is reached If the maximum pumping amount is not reached, step N and step G are sequentially performed. If the maximum pumping amount is reached, step H is performed. In step I, if the total amount of depression does not reach the maximum For the amount of pressure, step M is performed first, and then step F, step N and step G are performed in sequence.