Excimer laser annealing device and preparation method of polycrystalline silicon thin film

Abstract

The invention provides an excimer laser annealing device and a preparation method of a polycrystalline silicon thin film, and the device comprises a substrate carrying platform which is used for carrying a to-be-processed substrate; the laser unit is used for emitting a laser beam to the bearing surface of the substrate bearing table, the laser beam has the extension length in the first direction, and the first direction is parallel to the to-be-processed substrate; the to-be-processed substrate comprises a first side edge and a second side edge which are adjacently arranged, the to-be-processed substrate is arranged on the substrate carrying table in the mode that the first side edge inclines relative to the reference direction, the reference direction is perpendicular to the first direction, and a plane defined by the reference direction and the first direction is parallel to the to-be-processed substrate; the substrate stage is movable relative to the laser beam in a second direction, the second direction being a vector direction inclined relative to both the first direction and the reference direction. According to the excimer laser annealing device and the preparation method of the polycrystalline silicon thin film, the utilization rate of the substrate can be improved.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to an excimer laser annealing device and a method for preparing a polysilicon thin film. Background Art

[0002] In the backplane technology of OLED (Organic Light Emitting Diode, OLED for short), the production of the polysilicon layer mainly adopts various production methods such as excimer laser annealing (ELA for short), solid phase crystallization or metal induced crystallization.

[0003] The polysilicon thin film of the active layer of the transistor in the backplane obtained by using the excimer laser annealing process is a method that can be mass-produced. The excimer laser annealing process is a relatively complex annealing process.

[0004] Excimer laser annealing equipment uses an excimer laser beam to irradiate the amorphous silicon film on the substrate to be processed for a short time to recrystallize it into a polycrystalline silicon film. In the actual processing process, it was found that the excimer laser annealing process has the problem of low substrate utilization due to the small effective scanning area of ​​the laser irradiation on the substrate. Summary of the invention

[0005] The embodiments of the present disclosure provide an excimer laser annealing device and a method for preparing a polysilicon thin film, which can improve substrate utilization.

[0006] The technical solutions provided by the embodiments of the present disclosure are as follows:

[0007] In a first aspect, an embodiment of the present disclosure provides an excimer laser annealing device, comprising:

[0008] A substrate carrier, used for carrying a substrate to be processed; and

[0009] A laser unit, the laser unit is used to emit a laser beam onto the carrying surface of the substrate carrier, and the laser beam has an extension length along a first direction, and the first direction is parallel to the substrate to be processed; wherein,

[0010] The substrate to be processed includes a first side edge and a second side edge that are adjacent to each other, and the substrate to be processed is arranged on the substrate carrier in a manner that the first side edge is inclined relative to a reference direction, the reference direction is perpendicular to the first direction, and a plane defined by the first direction is parallel to the substrate to be processed; the substrate carrier can move relative to the laser beam along a second direction, and the second direction is a vector direction that is inclined relative to both the first direction and the reference direction.

[0011] Exemplarily, the inclination angle of the first side relative to the reference direction is a first angle α, and the inclination angle of the second direction relative to the reference direction is a second angle β, wherein α≥β≥-α.

[0012] Exemplarily, α=β.

[0013] Exemplarily, the laser unit comprises:

[0014] A laser generator, used for emitting a laser beam;

[0015] a beam modulator, disposed on a side of the laser generator close to the substrate stage and located on an optical path of the laser beam, for modulating the laser beam into a predetermined shape having a predetermined length along the first direction; and

[0016] A slit assembly, wherein the slit assembly is arranged in the optical path of the laser beam and is located on the side of the beam modulator away from the laser generator. The slit assembly has a slit through which the laser beam can pass, and a first shielding member and a second shielding member that enclose the slit. The slit extends in a direction parallel to the second side, and the width of the slit in a direction perpendicular to its own extension direction is adjustable.

[0017] Exemplarily, the slit assembly further comprises:

[0018] A first movable member connected to the first shielding member;

[0019] The second movable member is connected to the second shielding member; wherein,

[0020] The first shielding member and the second shielding member are arranged opposite to each other in the second direction, and the gap between the first shielding member and the second shielding member forms the slit; the first movable member and the second movable member can move toward or away from each other along the reference direction or the second direction to adjust the width of the slit in a direction perpendicular to its extension direction.

[0021] Exemplarily, the slit assembly further comprises:

[0022] a first adjusting member connected between the first movable member and the first shielding member;

[0023] The second adjusting member is connected between the second movable member and the second shielding member; wherein,

[0024] The first adjusting member is movable relative to the first movable member, and drives the first shielding member to change its inclination angle relative to the second direction; and the second adjusting member is movable relative to the second movable member, and drives the second shielding member to change its inclination angle relative to the second direction, so that the extension direction of the slit can be adjusted.

[0025] Exemplarily, the first adjusting member includes a first connecting end connected to the first movable member, and a second connecting end connected to the first shielding member, wherein the first connecting end is pivotally connected to the first movable member, and the second connecting end is rotatable around the pivot point to drive the first shielding member to change its inclination angle relative to the second direction;

[0026] The second adjusting member includes a third connecting end connected to the second movable member and a fourth connecting end connected to the second shielding member, wherein the third connecting end is pivotally connected to the second movable member, and the fourth connecting end is rotatable around the pivot point to drive the inclination angle of the second shielding member relative to the second direction to change.

[0027] In a second aspect, the present disclosure also provides a method for preparing a polycrystalline silicon thin film, comprising the following steps:

[0028] forming an amorphous silicon thin film on a substrate to be processed;

[0029] The excimer laser annealing device as described above is used to anneal the amorphous silicon thin film of the substrate to be processed.

[0030] Exemplarily, the annealing of the amorphous silicon thin film of the substrate to be processed by using the excimer laser annealing device as described above specifically includes:

[0031] Carrying the substrate to be processed onto the substrate stage in a manner that the first side is inclined relative to the reference direction;

[0032] The laser unit emits a laser beam, and the substrate stage is controlled to move relative to the laser beam along a second direction, so as to perform laser scanning on the amorphous silicon thin film on the substrate to be processed.

[0033] Exemplarily, in the method, emitting a laser beam by the laser unit, controlling the substrate stage to move relative to the laser beam along a second direction to perform laser scanning on the amorphous silicon thin film on the substrate to be processed, specifically includes:

[0034] The slit of the slit assembly is arranged to extend parallel to the second side, and the first shielding member and the second shielding member are arranged along a direction from a laser scanning starting end to a laser scanning terminating end;

[0035] At the start of laser scanning, the slit is adjusted to a first width, wherein the first width is configured to enable only a portion of the laser beam to pass through the slit and be emitted toward the substrate to be processed, while another portion of the laser beam is blocked by the first shielding member;

[0036] In the middle stage of laser scanning, the slit is adjusted to a second width, wherein the second width is configured to enable the laser beam to completely pass through the slit and be emitted toward the substrate to be processed;

[0037] At the laser scanning termination stage, the slit is adjusted to a third width, and the third width is configured to enable only a portion of the laser beam to pass through the slit and radiate toward the substrate to be processed, while the other portion of the laser beam is blocked by the second shielding member.

[0038] Exemplarily, in the method, the laser unit emits a laser beam, and the substrate stage is controlled to move relative to the laser beam along a second direction to perform laser scanning on the amorphous silicon thin film on the substrate to be processed, and specifically further includes:

[0039] Assume that the duration of the entire laser scanning process is T, the moving speed of the substrate to be processed is v, the time when the substrate to be processed starts to move is taken as 0 as the reference, the duration of the initial stage of the laser scanning is t1, the duration of the intermediate stage of the laser scanning is t2, and the duration of the termination stage of the laser scanning is t3, t1 = b*tanα / v, t3 = b*tanα / v, t2 = T-t1-t2, wherein b is the length of the first side, and α is the inclination angle of the second side relative to the reference direction.

[0040] The beneficial effects brought by the embodiments of the present disclosure are as follows:

[0041] In the above scheme, the laser scanning path of the substrate to be processed is optimized, and the scanning in the reference direction perpendicular to the extension length of the laser beam in the related technology is improved to scanning in the vector direction inclined relative to the reference direction (i.e., the above-mentioned reference direction). In this way, during the laser scanning process, the substrate to be processed is displaced not only in the reference direction, but also in the direction parallel to the extension length of the laser beam. This can increase the area of ​​the substrate where laser scanning is performed in the reference direction, thereby effectively increasing the area of ​​the effective laser scanning area and improving the utilization rate of the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 A schematic diagram showing a laser scanning effective area when a substrate to be processed moves along a reference direction in the related art;

[0043] Figure 2 A schematic diagram showing a laser scanning effective area when a substrate to be processed moves along a second direction in an embodiment of the present disclosure;

[0044] Figure 3 A schematic diagram showing the structure of an excimer laser annealing device provided in an embodiment of the present disclosure, wherein only the first light shielding member and the second light shielding member are shown in the slit assembly;

[0045] Figure 4 A schematic diagram showing the structure of a slit assembly in an excimer laser annealing device provided in an embodiment of the present disclosure;

[0046] Figure 5 A schematic diagram showing an excimer laser annealing device provided in an embodiment of the present disclosure at an initial stage of laser scanning;

[0047] Figure 6 A schematic diagram showing the excimer laser annealing device provided in an embodiment of the present disclosure when transitioning from an initial stage of laser scanning to an intermediate stage of laser scanning;

[0048] Figure 7 A schematic diagram showing the excimer laser annealing device provided in an embodiment of the present disclosure during the transition of the laser scanning intermediate stage;

[0049] Figure 8 One of the schematic diagrams showing the excimer laser annealing device provided in the embodiment of the present disclosure when transitioning from the laser scanning intermediate stage to the laser scanning termination stage;

[0050] Fig. 9 The second schematic diagram shows the excimer laser annealing device provided in the embodiment of the present disclosure when transitioning from the middle stage of laser scanning to the termination stage of laser scanning. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0052] Unless otherwise defined, the technical terms or scientific terms used in the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, similar words such as "one", "one" or "the" do not indicate quantity restrictions, but indicate that there is at least one. Similar words such as "include" or "comprise" mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Similar words such as "connect" or "connected" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0053] The features such as "parallel", "perpendicular", and "same" used in the embodiments of the present disclosure include the features such as "parallel", "perpendicular", and "same" in a strict sense, as well as the cases where "approximately parallel", "approximately perpendicular", "approximately the same", etc. include certain tolerances, taking into account the tolerances associated with the measurement of specific quantities (e.g., the limitations of the measurement system), and represent the acceptable deviation range for a specific value determined by ordinary technicians in the field. For example, "approximately" can mean within one or more standard deviations, or within 3% or 5% of the value.

[0054] In addition, in this document, unless otherwise defined, the terms "substantially", "substantially", "approximately" and "about" are used to describe and explain small changes. When used with an event or situation, these terms can cover situations where the event or situation occurs exactly, and can also cover situations where the event or situation occurs approximately. For example, when used with a numerical value, these terms can include a range of variation of less than or equal to 10% of the numerical value, such as less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1%, less than or equal to ±0.5%, less than or equal to ±0.1%, less than or equal to ±0.05%. The term "substantially coplanar" can refer to two surfaces being arranged along the same plane in the micrometer range, for example, arranged along the same plane within 40μm, 30μm, 20μm, 10μm or 1μm.

[0055] It should be understood that in the exemplary embodiments of the present disclosure, when a layer or an element is referred to as being on another layer or substrate, the layer or element may be directly on the other layer or substrate, or there may be an intermediate layer between the layer or element and the other layer or substrate. "A and B are arranged on the same layer" means that after A and B adopt the same film forming process to form a film layer for forming a specific pattern, a layer structure is formed by a single patterning process using the same mask.

[0056] Excimer Laser Annealing (ELA) is a technology that uses excimer lasers to anneal materials. It is widely used in semiconductor manufacturing and thin film technology. This technology is mainly used to improve the crystal quality of thin film materials, improve electrical properties, and enhance the mechanical properties of materials.

[0057] Excimer lasers are short-wavelength lasers, usually in the ultraviolet spectrum (such as 193 nanometers or 248 nanometers). During the annealing process, laser pulses are irradiated onto the surface of the material, instantly heating the material to a molten or near-molten state. Because the laser pulse duration is extremely short (usually nanoseconds), the material cools rapidly after laser irradiation, forming a new crystal structure. This rapid heating and cooling process helps eliminate defects in the material and improve its crystallinity.

[0058] In the manufacturing process of OLED (Organic Light Emitting Diode), the Excimer Laser Annealing (ELA) process is used to irradiate the surface of the substrate to be processed with laser, so that amorphous silicon (A-Si) melts and recrystallizes into polycrystalline silicon (P-Si).

[0059] However, the excimer laser annealing process in the related art has the problem that the area covered by the laser irradiation on the substrate is small, resulting in a small crystallization area and low substrate utilization.

[0060] The inventors of this application have found through research that one of the reasons for the above problems is:

[0061] In the related art, an inclined scanning method is generally used during laser scanning. Specifically, the laser scanning direction is used as the reference direction, and the substrate carrier carries the substrate to be processed. Both are set at a certain angle (such as 1°, 3°, 5°, etc.) relative to the reference direction. The laser beam extends a specific width in the vertical reference direction, and the substrate carrier moves along the reference direction relative to the laser beam, so that the laser beam scans the surface of the substrate to be processed. Since the substrate to be processed is inclined at a certain angle relative to the scanning direction, and the laser beam extends a predetermined length in the vertical scanning direction, there will be a part of the substrate to be processed that is not irradiated by the laser.

[0062] In order to reduce static electricity and impurities, aluminum and other materials are usually used for the substrate stage. If the laser irradiates the surface of the substrate stage, it will damage the substrate stage and affect the crystallization effect. Therefore, when the laser is scanned, it is best not to irradiate the laser on the surface of the substrate stage other than the substrate to be processed.

[0063] In the related art, in order to avoid laser irradiation to the surface of the substrate stage as much as possible, during tilt scanning, the laser beam is used at a shorter length, or the laser scanning start position is moved as far inward as possible (i.e., close to the middle of the substrate to be processed). This results in a smaller effective scanning area, fewer crystallization areas, and low substrate utilization.

[0064] In order to improve the above problems, the embodiments of the present disclosure provide an excimer laser annealing device and a method for preparing a polysilicon thin film, which can improve the utilization rate of the substrate.

[0065] like Figure 2 As shown, the embodiment of the present disclosure provides an excimer laser annealing device, comprising:

[0066] The substrate carrier 100 is used to carry the substrate 200 to be processed; and

[0067] A laser unit 300, the laser unit 300 is used to emit a laser beam B onto the carrying surface of the substrate carrier 100, and the laser beam B has an extension length along a first direction X, and the first direction X is parallel to the substrate to be processed 200; wherein,

[0068] The substrate to be processed 200 includes a first side 210 and a second side 220 that are adjacently arranged, and the substrate to be processed 200 is arranged on the substrate carrier 100 in a manner that the first side 210 is inclined relative to a reference direction Y, the reference direction Y is perpendicular to the first direction X, and a plane defined by the first direction X is parallel to the substrate to be processed 200; the substrate carrier 100 can move relative to the laser beam B along a second direction R, and the second direction R is a vector direction that is inclined relative to both the first direction X and the reference direction Y.

[0069] In the above scheme, the extension length direction of the laser beam B (i.e., the first direction X) is taken as the X-axis direction, and the reference direction Y perpendicular to the first direction X is taken as the Y-axis direction. Then, the substrate 200 to be processed is moved relative to the laser beam B along the second direction R inclined relative to both the X-axis and the Y-axis, thereby optimizing the laser scanning path of the substrate 200 to be processed, and the scanning along the reference direction Y perpendicular to the extension length of the laser beam B in the related art is improved to the scanning in the vector direction inclined relative to the reference direction Y, so that during the laser scanning process, the substrate 200 to be processed is displaced not only in the reference direction Y, but also in the direction parallel to the extension length of the laser beam B. In this way, the area of ​​the substrate for laser scanning in the Y-axis direction can be enlarged, thereby effectively increasing the area of ​​the effective area of ​​the laser scanning and improving the utilization rate of the substrate.

[0070] Specifically, Figure 1 It is a schematic diagram of the laser scanning effective area when the substrate 200 to be processed moves along the reference direction (Y axis) for laser scanning in the related art; Figure 2 It is a schematic diagram of the laser scanning effective area when the excimer laser annealing device provided by the embodiment of the present disclosure moves the substrate 200 to be processed along the second direction R for laser scanning.

[0071] See also Figure 1 As shown, in the related art, when laser scanning is performed, the scanning path of the substrate to be processed 200 is along the Y axis, while in the embodiment of the present disclosure, the scanning path of the substrate to be processed 200 has an inclined angle with the Y axis. Assuming that the inclination angle of the substrate to be processed 200 relative to the reference direction Y remains unchanged, the scanning path of the substrate to be processed 200 is improved from moving along the reference direction Y to moving along the second direction R. In the related art, the laser beam B scans the laser scanning effective area C1 on the surface of the substrate to be processed 200 along the reference direction Y, and the size along the reference direction Y is Ly, and the size of the laser beam B scanning the surface of the substrate to be processed 200 along the first direction X is Dx; after optimizing the moving path of the substrate to be processed 200 in the embodiment of the present disclosure, as shown in FIG. Figure 2 As shown, the laser scanning effective area formed by the laser beam B passing through the surface of the substrate to be processed 200 along the second direction R is C2, the size of the laser scanning effective area C2 along the second direction R is L(x+y), and the size of the laser beam B scanning the surface of the substrate to be processed 200 along the first direction X is D(x+y). Obviously, L(x+y)>Ly, D(x+y)>Dx, therefore, after the embodiment of the present disclosure optimizes the moving path of the substrate to be processed 200, the area of ​​the laser scanning effective area is increased.

[0072] As an exemplary embodiment, Figure 2As shown, the inclination angle of the first side 210 relative to the reference direction Y is a first angle α, and the inclination angle of the second direction R relative to the reference direction Y is a second angle β, wherein α≥β≥-α.

[0073] With the above scheme, the value of the inclination angle of the moving direction of the substrate 200 to be processed relative to the reference direction Y should be reasonably selected to obtain a larger effective area of ​​the laser scanning. The inventor of the present application has found through research that the moving direction of the substrate 200 to be processed is related to the inclination angle of the first side 210 of the substrate 200 to be processed relative to the reference direction Y. When α≥β≥-α, a larger effective area of ​​the laser scanning can be obtained. Exemplarily, α=β, that is, the moving direction of the substrate 200 to be processed and the extension direction of the first side 210 of the substrate 200 to be processed can be substantially the same.

[0074] As an exemplary embodiment, Figure 3 As shown, the laser unit 300 includes: a laser generator (not shown in the figure), a beam modulator 320 and a slit assembly 330. The laser generator is used to emit a laser beam B. The beam modulator 320 is arranged on a side of the laser generator 310 close to the substrate stage 100 and is located on the optical path of the laser beam B, and is used to modulate the laser beam B into a predetermined shape with a predetermined length along the first direction X, for example, Figure 3 As shown, the laser beam B can be modulated into a linear laser beam with a predetermined length along the first direction X by the beam modulator 320; the slit assembly 330 is arranged on the optical path of the laser beam B and is located on the side of the beam modulator 320 away from the laser generator 310, and the slit assembly 330 has a slit 331 for allowing the laser beam B to pass through, and a first shielding member 332 and a second shielding member 333 that enclose the slit 331, and the width of the slit 331 in a direction perpendicular to its own extension is adjustable.

[0075] By adopting the above scheme, the slit assembly 330 is set, and the width of the slit 331 on the slit assembly 330 is set to be adjustable. In this way, the width of the slit 331 can be adjusted in different scanning stages to control the shielding range of the slit 331 on the laser beam B, thereby adjusting the irradiation range of the laser beam B on the substrate 200 to be processed in different scanning stages, so as to increase the effective area of ​​the laser scanning and avoid the laser irradiating the surface of the substrate carrier 100.

[0076] It should be noted that, in combination with the optimization of the scanning path, the width of the slit 331 is adjusted in different laser scanning stages to control the shielding range of the laser beam B by the slit 331. For example, the laser scanning process may include a laser scanning start stage, a laser scanning middle stage, and a laser scanning end stage. Excess laser light may be shielded in the laser scanning start stage and the laser scanning end stage, and laser light may not be shielded in the scanning middle stage. It should be understood that the above is only an example and is not limited thereto.

[0077] As an exemplary embodiment, 3 and Figure 4 As shown, the slit assembly 330 further includes:

[0078] A first movable member 334 connected to the first shielding member 332;

[0079] The second movable member 335 is connected to the second shielding member 333; wherein,

[0080] The first shielding member 332 and the second shielding member 333 are disposed opposite to each other in the second direction R, and a gap between the first shielding member 332 and the second shielding member 333 forms the slit 331;

[0081] The first movable member 334 and the second movable member 335 can move toward or away from each other along the reference direction Y or the second direction R to adjust the width of the slit 331 in a direction perpendicular to the extending direction thereof.

[0082] By adopting the above scheme, the slit assembly 330 can be relatively arranged by two shielding members (a first shielding member 332 and a second shielding member), and the gap between the two shielding members is used to form the slit 331, and the two shielding members are respectively connected to a movable member, and the width of the slit 331 is adjusted by moving the movable member. The structure is simple and the operation is convenient.

[0083] As an exemplary embodiment, the first light shielding member and the second shielding member 333 may be implemented by, but not limited to, shielding plates; the first moving member and the second moving member may be implemented by, but not limited to, moving plates.

[0084] In addition, as an exemplary embodiment, Figure 4 As shown, the slit assembly 330 further includes:

[0085] A first adjusting member 336 connected between the first movable member 334 and the first shielding member 332;

[0086] The second adjusting member 337 is connected between the second movable member 335 and the second shielding member 333; wherein,

[0087] The first adjusting member 336 is movable relative to the first movable member 334, and drives the first shielding member 332 to change its inclination angle relative to the second direction R; and the second adjusting member 337 is movable relative to the second movable member 335, and drives the second shielding member 333 to change its inclination angle relative to the second direction R, so that the extension direction of the slit 331 can be adjusted.

[0088] For example, the slit 331 may be adjusted to extend in a direction parallel to the second side 220, see Figure 5 As shown, along the direction from the initial end of the laser scanning to the termination end of the laser scanning, the first shielding member 332 and the second shielding member 333 can be arranged in sequence. In the initial stage of the laser scanning, the first shielding member 332 can block a part of the laser beam B, and the edge of the slit 331 formed by the first shielding member 332 can be flush with the first side 210 of the substrate to be processed 200, so that the laser beam B can be effectively prevented from irradiating the area outside the first side 210 of the substrate to be processed 200; in the termination stage of the laser scanning, the second shielding member 333 can block a part of the laser beam B, and the edge of the slit 331 formed by the second shielding member 333 can be flush with the third side of the substrate to be processed 200, so that the laser beam B can be effectively prevented from irradiating the area outside the third side of the substrate to be processed 200.

[0089] For different application scenarios, the inclination angle of the substrate to be processed 200 is different. By adjusting the inclination angles of the first shielding member 332 and the second shielding member 333 , the slit 331 can be adjusted to extend in a direction parallel to the second side 220 .

[0090] As an exemplary embodiment, Figure 4 As shown, the first adjusting member 336 and the first movable member 334 can be rotatably connected at the hinge through the first rotating shaft 338, and the second adjusting member 337 and the second movable member 335 can be rotatably connected at the hinge through the second rotating shaft 339. The first rotating shaft 338 and the second rotating shaft 339 can be driven to rotate by a motor to achieve the adjustment of the extension direction of the slit 331.

[0091] As an exemplary embodiment, Figure 4As shown, the first adjusting member 336 includes a first connecting end 3361 connected to the first movable member 334, and a second connecting end 3362 connected to the first shielding member 332, wherein the first connecting end 3361 is pivotally connected to the first movable member 334, and the second connecting end 3362 is rotatable around the pivot point to drive the first shielding member 332 to change its inclination angle relative to the second direction R;

[0092] The second adjusting member 337 includes a third connecting end 3371 connected to the second movable member 335, and a fourth connecting end 3372 connected to the second shielding member 333, wherein the third connecting end is pivotally connected to the second movable member 335, and the fourth connecting end is rotatable around the pivot point to drive the inclination angle of the second shielding member 333 relative to the second direction R to change.

[0093] By adopting the above solution, the tilt angle of the first shielding member 332 can be adjusted by adjusting the rotation angle of the first adjusting member 336 around the pivot point between the first adjusting member 336 and the first movable member 334; similarly, the tilt angle of the second shielding member 333 can be adjusted by adjusting the rotation angle of the second adjusting member 337 around the pivot point between the second movable member 335. In other words, the extension direction of the slit 331 is adjusted. This adjustment method has a simple structure and is easy to operate.

[0094] As an exemplary embodiment, Figure 4 As shown, either the first adjusting member 336 or the second adjusting member 337 may include a first rod 33a and a second rod 33b, the first rod 33a and the second rod 33b are cross-connected, and the intersection of the first rod 33a and the second rod 33b in the first adjusting member 336 is pivoted to the first movable member 334 as the first connecting end, the end of the first rod 33a and the second rod 33b in the first adjusting member 336 away from the intersection is used as the second connecting end, and is respectively connected to the first shielding member 332. Similarly, the intersection of the first rod 33a and the second rod 33b in the second adjusting member 337 is used as the third connecting end, which is pivoted to the second movable member 335, and the end of the first rod 33a and the second rod 33b in the second adjusting member 337 away from the intersection is used as the fourth connecting end, which is respectively connected to the second shielding member 333.

[0095] As an exemplary embodiment, Figure 4 As shown, the first rod 33a and the second rod 33b are not equal in length. However, in other embodiments not shown, the first rod 33a and the second rod 33b may also be the same in length.

[0096] In addition, the present disclosure also provides a method for preparing a polycrystalline silicon thin film, comprising the following steps:

[0097] Step S01, forming an amorphous silicon thin film on a substrate 200 to be processed;

[0098] Step S02, using the excimer laser annealing device provided in the embodiment of the present disclosure to anneal the amorphous silicon thin film of the substrate 200 to be processed, the above step S02 specifically includes:

[0099] Step S021, placing the substrate 200 to be processed on the substrate stage 100 in a manner such that the first side 210 is inclined relative to the reference direction Y;

[0100] Step S022 , emitting a laser beam B through the laser unit 300 , and controlling the substrate stage 100 to move along a second direction R relative to the laser beam B, so as to perform laser scanning on the amorphous silicon thin film on the substrate 200 to be processed.

[0101] Since the principle of solving the problem by the method for preparing the polysilicon thin film is similar to the principle of solving the problem by the above-mentioned excimer laser annealing device, it is obvious that this method can also bring about the beneficial effects brought by the above-mentioned excimer laser annealing device, and will not be elaborated here.

[0102] In addition, illustratively, in the method, the above step S022 specifically includes:

[0103] Step S0221, arranging the slit 331 of the slit assembly 330 to extend parallel to the second side 220, and arranging the first shielding member 332 and the second shielding member 333 along the direction from the laser scanning starting end to the laser scanning ending end;

[0104] Step S0222, at the start stage of laser scanning, adjusting the slit 331 to a first width, wherein the first width is configured to enable only a portion of the laser beam B to pass through the slit 331 and be emitted toward the substrate 200 to be processed, while the other portion of the laser beam B is blocked by the first shielding member 332;

[0105] Step S0223, in the middle stage of laser scanning, adjusting the slit 331 to a second width, wherein the second width is configured to enable the laser beam B to completely pass through the slit 331 and be emitted toward the substrate 200 to be processed;

[0106] Step S0224, at the laser scanning termination stage, the slit 331 is adjusted to a third width, and the third width is configured to enable only a portion of the laser beam B to pass through the slit 331 and be emitted to the substrate 200 to be processed, and the other portion of the laser beam B is blocked by the second shielding member 333.

[0107] In the above scheme, the slit 331 can be adjusted to extend in a direction parallel to the second side 220, and the first shielding member 332 and the second shielding member 333 can be arranged in sequence along the direction from the initial end of the laser scanning to the termination end of the laser scanning. In the initial stage of the laser scanning, the first shielding member 332 can block a part of the laser beam B, and the edge of the slit 331 formed by the first shielding member 332 can be flush with the first side 210 of the substrate to be processed 200, so that the laser beam B can be effectively prevented from irradiating the area outside the first side 210 of the substrate to be processed 200; in the termination stage of the laser scanning, the second shielding member 333 can block a part of the laser beam B, and the edge of the slit 331 formed by the second shielding member 333 can be flush with the third side of the substrate to be processed 200, so that the laser beam B can be effectively prevented from irradiating the area outside the third side of the substrate to be processed 200.

[0108] It should be noted that during the transition from the initial stage of laser scanning to the intermediate stage of laser scanning, and during the transition from the intermediate stage of laser scanning to the terminal stage of laser scanning, the width change trend of the slit 331 of the slit assembly 330 is: first gradually increase from the first width to the second width, then keep the second width unchanged, and finally gradually decrease from the second width to the third width.

[0109] For details, please refer to the attached Figures 5 to 9 As shown, in the process of transitioning from the initial stage of laser scanning to the intermediate stage of laser scanning, at the beginning of laser scanning, the slit 331 of the slit assembly 330 extends parallel to the first side edge 210, and the first shielding member 332 forms a side edge of the slit 331 flush with the first side edge 210, and the width of the slit 331 between the second shielding member 333 and the first shielding member 332 is the first width ( Figure 5 As shown in FIG. 1 , the second shielding member 333 in the slit assembly 330 can move along with the substrate to be processed 200, so that the range of the laser beam B irradiated on the substrate to be processed 200 gradually increases to a second width ( Figure 6 In the intermediate stage of the laser scanning, the width of the slit 331 of the slit assembly 330 remains unchanged at the second width until the position where the laser scanning intermediate stage needs to transition to the laser scanning termination stage ( Figure 7 As the substrate 200 to be processed moves, the slit assembly 330 begins to gradually shield the laser beam B so that the laser beam B is controlled within the expected irradiation range ( Figure 8As the substrate 200 to be processed moves, the slit assembly 330 moves with the substrate 200 to be processed, so that the range of the laser beam B irradiating the substrate 200 to be processed gradually decreases until the laser scanning of the entire substrate 200 to be processed is completed ( Fig. 9 shown).

[0110] Herein, assuming that the duration of the entire laser scanning process is T, the moving speed of the substrate 200 to be processed is v, the time when the substrate 200 to be processed starts to move is taken as 0 as a reference, the duration of the initial stage of the laser scanning is t1, the duration of the intermediate stage of the laser scanning is t2, and the duration of the termination stage of the laser scanning is t3.

[0111] Among them, t1=L1 / v. According to the principle of geometry, L1 is the length of the area outside the substrate 200 to be processed that is not irradiated by the laser beam B along the second direction R, that is, the length of the short side a of the triangle A in the figure, where a is equal to b*tanα, so t1=b*tanα / v, b is the length of the second side 220, and α is the inclination angle of the first side 210 relative to the reference direction Y.

[0112] Based on the same principle, t3 = b*tanα / v, t2 = T-t1-t2.

[0113] It should be understood that the above is only an example, and in actual application, the width adjustment method of the slit assembly 330 is not limited to this.

[0114] There are a few points to note:

[0115] (1) The drawings of the embodiments of the present disclosure only relate to the structures related to the embodiments of the present disclosure, and other structures may refer to the general design.

[0116] (2) For the sake of clarity, in the drawings used to describe the embodiments of the present disclosure, the thickness of layers or regions is exaggerated or reduced, that is, these drawings are not drawn according to the actual scale. It is understood that when an element such as a layer, film, region or substrate is referred to as being "on" or "under" another element, the element may be "directly" "on" or "under" the other element or there may be intermediate elements.

[0117] (3) In the absence of conflict, the embodiments of the present disclosure and the features therein may be combined with each other to obtain new embodiments.

[0118] The above are only specific implementations of the present disclosure, but the protection scope of the present disclosure is not limited thereto, and the protection scope of the present disclosure shall be based on the protection scope of the claims.

Claims

1. An excimer laser annealing device, characterized in that: include: A substrate carrier, used for carrying a substrate to be processed; and A laser unit, the laser unit is used to emit a laser beam onto the carrying surface of the substrate carrier, and the laser beam has an extension length along a first direction, and the first direction is parallel to the substrate to be processed; wherein, The substrate to be processed comprises a first side and a second side that are adjacently arranged, and the substrate to be processed is arranged on the substrate stage in a manner that the first side is inclined relative to a reference direction, the reference direction is perpendicular to the first direction, and a plane defined by the first direction is parallel to the substrate to be processed; The substrate stage is movable relative to the laser beam along a second direction, where the second direction is a vector direction inclined relative to both the first direction and the reference direction.

2. The excimer laser annealing device according to claim 1, characterized in that: The inclination angle of the first side relative to the reference direction is a first angle α, and the inclination angle of the second direction relative to the reference direction is a second angle β, wherein α≥β≥-α.

3. The excimer laser annealing device according to claim 2, characterized in that: α＝β。 4. The excimer laser annealing device according to claim 1, characterized in that: The laser unit comprises: A laser generator, used for emitting a laser beam; a beam modulator, disposed on a side of the laser generator close to the substrate stage and located on an optical path of the laser beam, for modulating the laser beam into a predetermined shape having a predetermined length along the first direction; and A slit assembly, wherein the slit assembly is arranged in the optical path of the laser beam and is located on the side of the beam modulator away from the laser generator. The slit assembly has a slit through which the laser beam can pass, and a first shielding member and a second shielding member that enclose the slit. The slit extends in a direction parallel to the second side, and the width of the slit in a direction perpendicular to its own extension direction is adjustable.

5. The excimer laser annealing device according to claim 4, characterized in that: The slit assembly further comprises: A first movable member connected to the first shielding member; The second movable member is connected to the second shielding member; wherein, The first shielding member and the second shielding member are arranged opposite to each other in the second direction, and the gap between the first shielding member and the second shielding member forms the slit; the first movable member and the second movable member can move toward or away from each other along the reference direction or the second direction to adjust the width of the slit in a direction perpendicular to its extension direction.

6. The excimer laser annealing device according to claim 5, characterized in that: The slit assembly further comprises: a first adjusting member connected between the first movable member and the first shielding member; The second adjusting member is connected between the second movable member and the second shielding member; wherein, The first adjusting member is movable relative to the first movable member, and drives the first shielding member to change its inclination angle relative to the second direction; and the second adjusting member is movable relative to the second movable member, and drives the second shielding member to change its inclination angle relative to the second direction, so that the extension direction of the slit can be adjusted.

7. The excimer laser annealing device according to claim 6, characterized in that: The first adjusting member includes a first connecting end connected to the first movable member and a second connecting end connected to the first shielding member, wherein the first connecting end is pivotally connected to the first movable member, and the second connecting end is rotatable around the pivotal position to drive the first shielding member to change its inclination angle relative to the second direction; The second adjusting member includes a third connecting end connected to the second movable member and a fourth connecting end connected to the second shielding member, wherein the third connecting end is pivotally connected to the second movable member, and the fourth connecting end is rotatable around the pivot point to drive the inclination angle of the second shielding member relative to the second direction to change.

8. A method for preparing a polycrystalline silicon thin film, characterized in that: The steps include: forming an amorphous silicon thin film on a substrate to be processed; Annealing the amorphous silicon thin film of a substrate to be processed using the excimer laser annealing device according to any one of claims 1 to 7 specifically comprises: Carrying the substrate to be processed onto the substrate stage in a manner that the first side is inclined relative to the reference direction; The laser unit emits a laser beam, and the substrate stage is controlled to move relative to the laser beam along a second direction, so as to perform laser scanning on the amorphous silicon thin film on the substrate to be processed.

9. The method for preparing a polycrystalline silicon thin film according to claim 8, characterized in that: When applied to the excimer laser annealing device as claimed in claim 4, in the method, emitting a laser beam by the laser unit, controlling the substrate stage to move relative to the laser beam along a second direction to perform laser scanning on the amorphous silicon thin film on the substrate to be processed, specifically includes: The slit of the slit assembly is arranged to extend parallel to the second side, and the first shielding member and the second shielding member are arranged along a direction from a laser scanning starting end to a laser scanning terminating end; At the start of laser scanning, the slit is adjusted to a first width, wherein the first width is configured to enable only a portion of the laser beam to pass through the slit and be emitted toward the substrate to be processed, while another portion of the laser beam is blocked by the first shielding member; In the middle stage of laser scanning, the slit is adjusted to a second width, wherein the second width is configured to enable the laser beam to completely pass through the slit and be emitted toward the substrate to be processed; At the laser scanning termination stage, the slit is adjusted to a third width, and the third width is configured to enable only a portion of the laser beam to pass through the slit and radiate toward the substrate to be processed, while the other portion of the laser beam is blocked by the second shielding member.

10. The method for preparing a polycrystalline silicon thin film according to claim 9, characterized in that: In the method, the laser unit emits a laser beam, and the substrate stage is controlled to move relative to the laser beam along a second direction to perform laser scanning on the amorphous silicon thin film on the substrate to be processed, and specifically includes: Assume that the duration of the entire laser scanning process is T, the moving speed of the substrate to be processed is v, and the time when the substrate to be processed starts to move is taken as 0 as the reference. The duration of the initial stage of the laser scanning is t1, the duration of the middle stage of the laser scanning is t2, and the duration of the termination stage of the laser scanning is t3. t1 = b*tanα / v, t3 = b*tanα / v, t2 = T-t1-t2, wherein b is the length of the second side, and α is the inclination angle of the first side relative to the reference direction.

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