Laser drilling method for TFT substrate and bearing tool

Abstract

The invention discloses a laser drilling method for a TFT substrate and a bearing tool, and relates to the technical field of semiconductor machining, on the first aspect, the laser drilling method for the TFT substrate comprises the following steps that S1, the substrate is placed on a heating table, the temperature of the heating table is controlled to range from 100 DEG C to 300 DEG C, and the position, to be drilled, of the substrate is preheated; and S2, laser drilling is conducted on the preheated TFT product through a laser device, laser circularly moves on a drilling path, the laser scanning speed is 5-20 m / s, and the laser power is 10-50 W. On the second aspect, the laser drilling bearing tool for the TFT substrate comprises a laser, is applied to the laser drilling method for the TFT substrate and further comprises a heating table, and the heating table comprises a heating module, a temperature control unit and a fixing mechanism used for fixing the substrate. According to the laser drilling device, the substrate can be heated before laser drilling is carried out on the substrate, and the situation that the substrate is rapidly heated and cracks are generated when laser drilling is carried out on the substrate is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor processing, and in particular to a laser drilling method for a TFT substrate and a carrying tool. Background Art

[0002] In the manufacturing of thin-film transistors (TFTs), laser drilling technology is widely used in micro-hole processing due to its high precision, non-contact and strong controllability, such as conducting electrodes, connecting circuit layers or adjusting device structures. It also facilitates the subsequent metallization of the substrate.

[0003] The existing drilling method is 355nm ultraviolet galvanometer laser drilling. The TFT product is a ferrite with a cubic crystal structure. At the initial moment of laser drilling, the surface is heated and the local area is heated rapidly. The local cubic crystal is heated rapidly, causing local internal stress in the product, resulting in a certain probability of cracking problems. Summary of the invention

[0004] The object of the present invention is to provide a laser drilling method and a carrying tool for a TFT substrate, which can heat the substrate before laser drilling to avoid cracking of the substrate due to rapid heating during laser drilling.

[0005] In order to solve the above technical problems, the present invention adopts the following solutions: In a first aspect, a laser drilling method for a TFT substrate comprises the following steps: Step S1: placing the substrate on a heating platform, controlling the temperature of the heating platform to 100°C to 300°C, and preheating the substrate where holes are to be drilled; Step S2: Use a laser to perform laser drilling on the preheated TFT product, so that the laser moves cyclically on the drilling path, wherein the laser scanning speed is 5-20 m / s and the laser power is 10-50 W. Its function is to avoid the phenomenon of cracking caused by excessive temperature difference caused by instantaneous overheating of the substrate during laser drilling through the design of the preheating step; by reducing the laser power and increasing the laser scanning speed, the original high-power laser direct cutting and drilling is changed to multiple cyclic scanning and cutting and drilling, which reduces the heating temperature of the substrate per unit time, so that the heating temperature of the substrate rises slowly, thereby avoiding the cracking of the substrate due to rapid heating.

[0006] Furthermore, step S1 first preheats the substrate as a whole and then preheats the scanning path of the laser drilling of the substrate for a second time. The effect is that, by preheating the substrate as a whole first and then preheating the local part, the temperature of the laser scanning path can be made as close to the laser temperature as possible and the temperature difference of each part of the substrate is small, and compared with the method of directly heating the substrate as a whole throughout the whole process, the heating power can be effectively saved.

[0007] Furthermore, the preheating temperature of the heating table in step S1 is 150°C to 250°C.

[0008] Furthermore, the preheating time in step S1 is 30 to 120 seconds, and the temperature fluctuation range of the heating stage during the preheating process does not exceed ±5°C.

[0009] Furthermore, step S2 also includes: monitoring the substrate surface temperature in real time during the laser drilling process, and dynamically adjusting the laser power and scanning speed according to the temperature feedback, so as to further avoid the generation of cracks caused by excessive laser power and excessive scanning speed during the laser drilling process.

[0010] In a second aspect, a laser drilling tool for a TFT substrate includes a laser, which is applied to the above-mentioned laser drilling method for a TFT substrate, and also includes a heating platform, which includes a heating module, a temperature control unit, and a fixing mechanism for fixing the substrate. The function of the heating platform is to ensure that the temperature of the substrate reaches the target temperature through the setting of the temperature control unit.

[0011] Furthermore, the fixing mechanism includes a base plate, which is provided with two longitudinal tracks parallel to each other, and two transverse tracks parallel to each other are slidably connected to the longitudinal tracks. Two support platforms are slidably connected to each transverse track, and each support platform is provided with two side walls arranged perpendicular to each other. All side walls on the four support platforms constitute the four vertices of a rectangle.

[0012] Furthermore, the bottom plate is provided with a driving motor, the driving motor is connected to a driving screw, the driving screw is arranged parallel to the longitudinal track, an active sliding block is slidably connected to the longitudinal track adjacent to the driving screw, the active sliding block is threadedly connected to the driving screw, and the active sliding block is located between the two transverse tracks. Furthermore, a driven sliding block is slidably connected to the longitudinal track away from the driving screw, the positions of the active sliding block and the driven sliding block correspond to each other, and a third track parallel to the transverse track is arranged between the active sliding block and the driven sliding block, and a heating module is slidably connected to the third track. Furthermore, an adjustment motor is provided on the driven sliding block, the adjustment motor is connected to an adjustment screw, one end of the adjustment screw away from the adjustment motor is located in the active sliding block, the adjustment screw is threadedly connected to the adjustment block, and the adjustment block is connected to the heating module.

[0013] Furthermore, the adjustment block is provided with a temperature sensor and a temperature control unit, and the temperature sensor and the heating module are both electrically connected to the temperature control unit.

[0014] Furthermore, the support platform is penetrated by a locking bolt for pressing on the transverse rail.

[0015] The present invention has the beneficial effects: 1. The design of the preheating step can avoid the phenomenon of cracking caused by excessive temperature difference due to instantaneous overheating of the substrate during laser drilling; by reducing the laser power and increasing the laser scanning speed, the original high-power laser direct cutting and drilling is changed to multiple cycles of scanning and cutting and drilling, which reduces the heating temperature of the substrate per unit time and makes the heating temperature of the substrate rise slowly, thereby avoiding the cracking of the substrate due to rapid heating; 2. By preheating the entire substrate first and then preheating the local substrate, the temperature of the laser scanning path can be made as close to the laser temperature as possible and the temperature difference of each part of the substrate is small. Compared with the method of directly heating the substrate as a whole throughout the whole process, the heating power can be effectively saved. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the top view of the load-bearing tooling in Example 1; Figure 2 This is a schematic diagram of the main structure of the load-bearing tooling in Example 1.

[0017] Figure numerals: 1. base plate; 2. longitudinal track; 3. transverse track; 4. support platform; 5. side wall; 6. drive motor; 7. drive screw; 8. active sliding block; 9. driven sliding block; 10. third track; 11. heating module; 12. adjustment motor; 13. adjustment screw; 14. adjustment block; 15. locking bolt. DETAILED DESCRIPTION

[0018] The present invention will be further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0019] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "longitudinal", "lateral", "horizontal", "inside", "outside", "front", "back", "top", "bottom" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the inventive product is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0020] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "disposed", "opened", "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] Example 1 In a first aspect, a laser drilling method for a TFT substrate comprises the following steps: Step S1: placing the substrate on a heating platform, controlling the temperature of the heating platform to 100°C to 300°C, and preheating the substrate where holes are to be drilled; Step S2: Use a laser to perform laser drilling on the preheated TFT product, so that the laser moves cyclically on the drilling path, wherein the laser scanning speed is 5-20 m / s and the laser power is 10-50 W. Its function is to avoid the phenomenon of cracking caused by excessive temperature difference caused by instantaneous overheating of the substrate during laser drilling through the design of the preheating step; by reducing the laser power and increasing the laser scanning speed, the original high-power laser direct cutting and drilling is changed to multiple cyclic scanning and cutting and drilling, which reduces the heating temperature of the substrate per unit time, so that the heating temperature of the substrate rises slowly, thereby avoiding the cracking of the substrate due to rapid heating.

[0022] Step S1 first preheats the substrate as a whole and then preheats the scanning path of the laser drilling of the substrate for a second time. By preheating the substrate as a whole first and then preheating the local part, the temperature of the laser scanning path can be made as close to the laser temperature as possible and the temperature difference of each part of the substrate is small, which can effectively save heating power compared with the method of directly heating the substrate as a whole.

[0023] The preheating temperature of the heating stage in step S1 is 150°C to 250°C.

[0024] The preheating time in step S1 is 30 to 120 seconds, and the temperature fluctuation range of the heating stage during the preheating process does not exceed ±5°C.

[0025] Step S2 also includes: monitoring the substrate surface temperature in real time during the laser drilling process, and dynamically adjusting the laser power and scanning speed according to the temperature feedback, so as to further avoid the generation of cracks caused by excessive laser power and excessive scanning speed during the laser drilling process.

[0026] In a second aspect, a laser drilling support tool for a TFT substrate includes a laser (not shown in the figure), which is applied to the laser drilling method of the TFT substrate described above, such as Figure 1 As shown, a heating platform is also included, and the heating platform includes a heating module 11, a temperature control unit and a fixing mechanism for fixing the substrate. Its function is to ensure that the temperature of the substrate reaches the target temperature through the setting of the temperature control unit.

[0027] The fixing mechanism includes a bottom plate 1, on which two longitudinal rails 2 are provided, on which two transverse rails 3 are slidably connected, on which two support platforms 4 are slidably connected, and on which two side walls 5 arranged perpendicular to each other are provided, and all the side walls 5 on the four support platforms 4 form the four vertices of a rectangle. The laser is arranged above the support platform 4, and the laser with a movable function is a prior art and will not be described in detail.

[0028] Specifically, Figure 1 As shown, the bottom plate 1 is provided with a driving motor 6, the driving motor 6 is connected with a driving screw 7, the driving screw 7 is arranged parallel to the longitudinal track 2, an active sliding block 8 is slidably connected on the longitudinal track 2 adjacent to the driving screw 7, the active sliding block 8 is threadedly connected with the driving screw 7, and the active sliding block 8 is located between the two transverse tracks 3. Specifically, Figure 1 As shown, a driven sliding block 9 is slidably connected to the longitudinal track 2 away from the driving screw 7, the active sliding block 8 corresponds to the position of the driven sliding block 9, and a third track 10 parallel to the transverse track 3 is arranged between the active sliding block 8 and the driven sliding block 9, and a heating module 11 is slidably connected to the third track 10. Specifically, Figure 1 As shown, the driven sliding block 9 is provided with an adjustment motor 12, the adjustment motor 12 is connected to an adjustment screw 13, the end of the adjustment screw 13 away from the adjustment motor 12 is located in the active sliding block 8, the adjustment screw 13 is threadedly connected to an adjustment block 14, and the adjustment block 14 is connected to the heating module 11.

[0029] Specifically, the adjustment block 14 is provided with a temperature sensor and a temperature control unit, and the temperature sensor and the heating module 11 are both electrically connected to the temperature control unit.

[0030] Specifically, Figure 1 , Figure 2 As shown, the support platform 4 is provided with a locking bolt 15 for pressing on the transverse rail 3. The support cylinder is threadedly connected with the locking bolt 15. A connecting block is provided between the longitudinal rail 2 and the transverse rail 3, and the connecting block is provided with a locking bolt 15 for pressing on the longitudinal rail 2.

[0031] The working principle of this embodiment is described as follows: first, adjust the positions of the four support platforms 4 so that the four top corners of the substrate are fixed by the side walls 5, and then tighten the locking bolts 15 to fix the positions of the four support platforms 4, and then control the drive motor 6 and the adjustment motor 12 to make the moving path of the heating module 11 pass through the bottom surface of the entire substrate, first perform an initial comprehensive heating of the bottom surface of the substrate to preliminarily increase the overall temperature of the substrate, and then control the drive motor 6 and the adjustment motor 12 to make the heating module 11 move in a circular motion along the laser drilling path, further heat the laser drilling path, and further increase the temperature of the path with laser drilling on the substrate, and then the laser emits a laser to start laser drilling of the substrate.

[0032] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. According to the technical essence of the present invention, within the spirit and principles of the present invention, any simple modification, equivalent replacement and improvement made to the above embodiment still falls within the protection scope of the technical solution of the present invention.

Claims

1. A laser drilling method for a TFT substrate, characterized in that: The following steps are involved: Step S1: placing the substrate on a heating platform, controlling the temperature of the heating platform to 100°C to 300°C, and preheating the substrate where holes are to be drilled; Step S2: using a laser to perform laser drilling on the preheated TFT product, so that the laser moves cyclically on the drilling path, wherein the laser scanning speed is 5-20 m / s and the laser power is 10-50 W.

2. The laser drilling method for a TFT substrate according to claim 1, characterized in that: In step S1, the substrate is preheated as a whole first and then the scanning path of the laser drilling of the substrate is preheated for a second time.

3. The laser drilling method for a TFT substrate according to claim 1, characterized in that: The preheating temperature of the heating stage in step S1 is 150°C to 250°C.

4. The laser drilling method for a TFT substrate according to claim 1, characterized in that: The preheating time in step S1 is 30 to 120 seconds, and the temperature fluctuation range of the heating stage during the preheating process does not exceed ±5°C.

5. The laser drilling method for a TFT substrate according to claim 1, characterized in that: Step S2 also includes: monitoring the substrate surface temperature in real time during the laser drilling process, and dynamically adjusting the laser power and scanning speed according to temperature feedback.

6. A laser drilling support tool for a TFT substrate, comprising a laser, characterized in that: A laser drilling method for a TFT substrate as claimed in any one of claims 1 to 5, further comprising a heating platform, the heating platform comprising a heating module (11), a temperature control unit and a fixing mechanism for fixing the substrate.

7. The laser drilling support tool for a TFT substrate according to claim 6, characterized in that: The fixing mechanism comprises a bottom plate (1), the bottom plate (1) being provided with two mutually parallel longitudinal tracks (2), the longitudinal tracks (2) being slidably connected to two mutually parallel transverse tracks (3), each transverse track (3) being slidably connected to two support platforms (4), each support platform (4) being provided with two side walls (5) arranged perpendicular to each other, and all the side walls (5) on the four support platforms (4) forming four vertices of a rectangle.

8. The laser drilling support tool for a TFT substrate according to claim 7, characterized in that: The base plate (1) is provided with a driving motor (6), the driving motor (6) is connected to a driving screw (7), the driving screw (7) is arranged parallel to the longitudinal track (2), an active sliding block (8) is slidably connected to the longitudinal track (2) adjacent to the driving screw (7), the active sliding block (8) is threadedly connected to the driving screw (7), and the active sliding block (8) is located between the two transverse tracks (3). A driven sliding block (9) is slidably connected to the longitudinal track (2) away from the driving screw (7), the active sliding block (8) and the driven sliding block (9) are located at positions corresponding to each other, and a third track (10) parallel to the transverse track (3) is provided between the active sliding block (8) and the driven sliding block (9), and a heating module (11) is slidably connected to the third track (10). An adjustment motor (12) is provided on the driven sliding block (9), the adjustment motor (12) is connected to an adjustment screw (13), one end of the adjustment screw (13) away from the adjustment motor (12) is located in the active sliding block (8), the adjustment screw (13) is threadedly connected to an adjustment block (14), and the adjustment block (14) is connected to the heating module (11).

9. The laser drilling support tool for a TFT substrate according to claim 8, characterized in that: The adjustment block (14) is provided with a temperature sensor and a temperature control unit, and the temperature sensor and the heating module (11) are both electrically connected to the temperature control unit.

10. The laser drilling support tool for a TFT substrate according to claim 7, characterized in that: The support platform (4) is provided with a locking bolt (15) penetrating therethrough and used for pressing on the transverse rail (3).

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