CN111446187B - Laser annealing equipment - Google Patents

Abstract

The invention discloses a laser annealing device, comprising: a deoxidizing chamber, an excimer laser generator positioned above the deoxidizing chamber, and an annealing chamber positioned below the deoxidizing chamber; the annealing chamber comprises a bearing table for bearing a substrate with an amorphous silicon film; the deoxidizing chamber includes: the bottom cover plate, the annealing window and the nitrogen conveying pipe; the bottom cover plate includes: a laser exit slit and a plurality of gas diffusion holes distributed around the laser exit slit; the nitrogen provided by the nitrogen conveying pipe fills the deoxidization chamber and is diffused to the bearing table through the laser emergent slit and each gas diffusion hole; laser emitted by the excimer laser generator is emitted to the bearing table through the annealing window and the laser emergent slit in sequence. By additionally arranging a plurality of gas diffusion holes around the laser emergent slit, the nitrogen atmosphere which is purged to the surface of the bearing table by the laser emergent slit and each gas diffusion hole is more uniform, the molten recrystallization region is ensured to be in a pure nitrogen environment, the crystallization quality is improved, and the product yield is further improved.

Description

A kind of laser annealing equipment

technical field

The invention relates to the technical field of display preparation, in particular to a laser annealing device.

Background technique

In flat panel display devices, Active Matrix Organic Light Emitting Diode (AMOLED) has become the future due to its advantages of high image quality, short response time of moving images, low power consumption, wide viewing angle and ultra-light and ultra-thin. The best choice for display technology. At present, in AMOLED, the polysilicon layer is produced in the backplane technology, including various production methods such as excimer laser annealing (ELA for short), solid-phase crystallization, or metal-induced crystallization. However, using the excimer laser annealing process to obtain the polysilicon thin film of the active layer of the transistor in the backplane is the only method that has achieved mass production.

The excimer laser annealing process is a relatively complicated annealing process. ELA equipment is a device that irradiates an amorphous silicon film on a substrate with an excimer laser beam for a short time to recrystallize it into a polysilicon film. In the related art, the nitrogen (N ₂ ) of the deoxidation chamber (Partial Sealing BOX or Oxygen Partial Degassing Module [OPDM]) contained in the ELA equipment is to carry the amorphous silicon ( a-Si) The surface of the stage (Stage) of the thin film is purged with N ₂ to reduce the influence of oxygen (O ₂ ) concentration on the crystal quality of amorphous silicon in the melting recrystallization region. However, this method tends to cause the nitrogen atmosphere at the laser exit slit to be unstable, which is specifically manifested in the phenomenon of nitrogen flow disorder (N ₂ Turbulence Mura) due to high local oxygen concentration, resulting in the transformation of amorphous silicon into polycrystalline silicon (p-Si) The area with high oxygen concentration shows crystallization abnormality and polysilicon film roughness (Roughness) is too large, which can easily lead to a short circuit (short) between the back-end gate (Gate) layer and the channel film layer composed of polysilicon, seriously affecting the transistor ( The electrical properties of TFT) will eventually lead to the overall dirty phenomenon after the back-end (ET) is lit, which will affect the product yield.

Contents of the invention

In view of this, an embodiment of the present invention provides a laser annealing device to improve crystal quality and improve product yield.

Therefore, a laser annealing device provided in an embodiment of the present invention includes: a deoxidation chamber, an excimer laser generator located above the deoxidation chamber, and an annealing chamber located below the deoxidation chamber, wherein,

The annealing chamber includes: a carrying platform, the carrying platform is used to carry a substrate with an amorphous silicon film;

The deoxidation chamber includes: a bottom cover plate, an annealing window and a nitrogen delivery pipe;

The bottom cover plate includes: a laser exit slit, and a plurality of gas diffusion holes distributed around the laser exit slit;

The nitrogen gas provided by the nitrogen delivery pipe fills the deoxidation chamber and diffuses to the carrying platform through the laser exit slit and each of the gas diffusion holes;

The laser emitted by the excimer laser generator sequentially passes through the annealing window and the laser exit slit to the carrying platform.

In a possible implementation manner, in the above-mentioned laser annealing equipment provided by the embodiment of the present invention, in the extending direction of the laser exit slit, each of the gas diffusion holes is arranged in multiple rows, and the gas diffusion holes in each row The row spacing between the holes increases as the distance from the laser exit slit increases.

In a possible implementation manner, in the above-mentioned laser annealing device provided by the embodiment of the present invention, the gas diffusion holes in adjacent rows are staggered from each other.

In a possible implementation manner, in the above-mentioned laser annealing device provided by the embodiment of the present invention, the distances between adjacent gas diffusion holes in each row are the same.

In a possible implementation manner, in the above-mentioned laser annealing device provided by the embodiment of the present invention, the distance between the gas diffusion holes at both ends of each row and the center of the end face of the laser exit slit is the same.

In a possible implementation manner, in the above-mentioned laser annealing device provided by the embodiment of the present invention, the gas diffusion hole is a tapered hole, and the wide angle of the tapered hole is 60°-120°.

In a possible implementation manner, in the above-mentioned laser annealing equipment provided by the embodiment of the present invention, the deoxidation chamber further includes: a plurality of first oxygen detectors, and the plurality of first oxygen detectors are respectively arranged in The boundary of the region where the gas diffusion hole is located at both ends of the laser exit slit in the extending direction, and the intersection of the two ends and the center of the laser exit slit with the boundary of the bottom cover.

In a possible implementation manner, in the above-mentioned laser annealing equipment provided by the embodiment of the present invention, the annealing chamber further includes: a plurality of first nitrogen diffusers located under the carrying table, and a plurality of first nitrogen diffusers located under each of the a plurality of second nitrogen diffusers below the plane of the first nitrogen diffusers;

Orthographic projections of the plurality of second nitrogen diffusers on the bottom surface of the annealing chamber are respectively located at both ends and the center of the bottom surface of the annealing chamber perpendicular to the plane where the door of the annealing chamber is located;

Orthographic projections of the plurality of first nitrogen diffusers on the bottom surface of the annealing chamber are respectively located at the center of the line connecting the orthographic projections of the adjacent second nitrogen diffusers on the bottom surface of the annealing chamber;

The distance between the plane where each first nitrogen diffuser is located and the bottom surface of the annealing chamber is twice the distance between the plane where each second nitrogen diffuser is located and the bottom surface of the annealing chamber.

In a possible implementation manner, in the above-mentioned laser annealing equipment provided by the embodiment of the present invention, the annealing chamber further includes: a plurality of second oxygen detectors;

Part of the orthographic projections of the second oxygen detector on the bottom surface of the annealing chamber are respectively located at both ends of the bottom surface of the annealing chamber intersecting the plane where the door of the annealing chamber is located;

The rest of the orthographic projections of the second oxygen detector on the bottom surface of the annealing chamber are respectively located at both ends of the intersecting side of the side opposite to the door of the annealing chamber on the bottom surface of the annealing chamber;

The plane where the plurality of second oxygen detectors are located is an interface between each of the first nitrogen diffusers and each of the second nitrogen diffusers.

In a possible implementation manner, in the above-mentioned laser annealing equipment provided by the embodiment of the present invention, the annealing chamber further includes: a plurality of exhaust ports located on the bottom surface of the annealing chamber, a plurality of the exhaust ports The openings are respectively located at the centers of the boundaries of the bottom surface of the annealing chamber.

The beneficial effects of the present invention are as follows:

The laser annealing equipment provided by the embodiment of the present invention includes: a deoxidation chamber, an excimer laser generator located above the deoxidation chamber, and an annealing chamber located below the deoxidation chamber, wherein the annealing chamber includes: a carrying platform, and the carrying platform is used for carrying A substrate with an amorphous silicon film; a deoxidation chamber, including: a bottom cover plate, an annealing window and a nitrogen delivery pipe; a bottom cover plate, including: a laser exit slit, and a plurality of gas diffusion holes distributed around the laser exit slit; The nitrogen gas provided by the nitrogen delivery pipe fills the deoxidation chamber and diffuses to the carrying platform through the laser exit slit and each gas diffusion hole; the laser emitted by the excimer laser generator is directed to the carrying platform through the annealing window and the laser exit slit in turn. By adding a plurality of gas diffusion holes around the laser exit slit, the nitrogen atmosphere purged from the laser exit slit and each gas diffusion hole to the surface of the carrier is relatively uniform, thus ensuring that the laser irradiation at the laser exit slit The melting and recrystallization area on the amorphous silicon film is in a pure nitrogen environment without oxygen interference, which improves the crystallization quality and thus improves the product yield.

Description of drawings

Fig. 1 is the structural representation of the laser annealing equipment provided by the embodiment of the present invention;

Fig. 2 is a schematic structural view of the cover plate at the bottom of the deoxidation chamber provided by the embodiment of the present invention;

Fig. 3 is a simulation diagram of the nitrogen atmosphere effect in the melting recrystallization region provided by the embodiment of the present invention;

Fig. 4 is a schematic structural diagram of an annealing chamber provided by an embodiment of the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention more clear, the following will clearly and completely describe the technical solutions of the embodiments of the present invention in conjunction with the drawings of the embodiments of the present invention. Apparently, the described embodiments are some, not all, embodiments of the present invention. Based on the described embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Unless otherwise defined, the technical terms or scientific terms used herein shall have the usual meanings understood by those skilled in the art to which the present invention belongs. "First", "second" and similar words used in the description and claims of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Comprising" or "comprising" and similar words mean that the elements or items appearing before the word include the elements or items listed after the word and their equivalents, without excluding other elements or items. "Inner", "outer", "upper", "lower" and so on are only used to indicate relative positional relationship. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

It should be noted that the size and shape of each figure in the drawings do not reflect the actual scale, but are only intended to schematically illustrate the content of the present invention. And the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout.

A kind of laser annealing equipment that the embodiment of the present invention provides, as shown in Figure 1 and Figure 2, comprises: deoxidation chamber 001, the excimer laser generator (not shown in the figure) that is positioned at the deoxidation chamber 001 top, and the Annealing chamber 002 below 001, wherein,

The annealing chamber 002 includes: a carrying platform 201, which is used to carry a substrate with an amorphous silicon film;

Deoxidation chamber 001, comprising: bottom cover plate 101, annealing window 102 and nitrogen delivery pipe (not shown in the figure);

The bottom cover plate 101 includes: a laser exit slit 1011, and a plurality of gas diffusion holes 1012 distributed around the laser exit slit 1011;

The nitrogen gas provided by the nitrogen gas delivery pipe fills the deoxidation chamber 001 and diffuses to the carrying platform 201 through the laser exit slit 1011 and each gas diffusion hole 1012;

The laser light emitted by the excimer laser generator (shown by the oblique arrow in the figure) is irradiated to the carrier 201 through the annealing window 102 and the laser exit slit 1011 in sequence.

In the above-mentioned laser annealing equipment provided by the embodiment of the present invention, a plurality of gas diffusion holes 1012 are added around the laser emission slit 1011, so that The nitrogen atmosphere is relatively uniform, therefore, it is guaranteed that the molten recrystallized region on the amorphous silicon film irradiated by the laser at the laser exit slit 1011 is in a pure nitrogen environment, and there will be no interference of oxygen (derived from air), as shown in Figure 3, Thereby, the quality of crystallization can be improved, thereby improving the yield rate of products.

Optionally, in the above-mentioned laser annealing equipment provided by the embodiment of the present invention, as shown in FIG. The distance between the rows increases with the increase of the distance from the laser exit slit 1011 . Specifically, in FIG. 2 exemplarily, the distance between the first row of gas diffusion holes 1012 and the second row of gas diffusion holes 1012 on the side of the laser exit slit 1011 is a, and the second row of gas diffusion holes 1012 The distance between the third row of gas diffusion holes 1012 is b, the distance between the third row of gas diffusion holes 1012 and the fourth row of gas diffusion holes 1012 is c, where a<b<c.

Since the region on the amorphous silicon film corresponding to the laser exit slit 1011 is a melting and recrystallization region, the nitrogen diffusion in the edge region around the laser exit slit 1011 has a great influence on the quality of the melting and recrystallization. The row spacing between the holes 1012 increases with the increase of the distance from the laser exit slit 1011, so that the gas diffusion holes 1012 in the edge area around the laser exit slit 1011 are denser and farther away from the laser exit slit 1011 The gas diffusion holes 1012 in the area are slightly sparse. The densely arranged gas diffusion holes 1012 thus ensure that the nitrogen gas blown to the melting and recrystallization region is sufficient enough to be in an oxygen-free state, and the sparsely arranged gas diffusion holes 1012 can further reduce the oxygen that is displaced by the nitrogen gas in the melting and recrystallization region. The external discharge maintains the stability of the nitrogen atmosphere in the peripheral area of the melting and recrystallization area. In this way, no matter which direction is scanned (1500/1850), and no matter where the beam cutter is set, the uniform nitrogen content area is always larger than the scanning area, so as to avoid nitrogen disturbance due to high oxygen content around the beam cutter and other defects, so that the extremely low content of oxygen in the annealing chamber 002 is far away from the melting and crystallization position of amorphous silicon, thus solving various ET lighting defects caused by unstable atmosphere.

Optionally, in the above laser annealing equipment provided by the embodiment of the present invention, in order to enhance the uniformity of the nitrogen atmosphere, the gas diffusion holes 1012 in adjacent rows may be set to be staggered from each other, as shown in FIG. 2 .

Optionally, in the above-mentioned laser annealing device provided by the embodiment of the present invention, the distances between adjacent gas diffusion holes 1012 in each row are the same, so as to further enhance the uniformity of the nitrogen atmosphere.

Optionally, in the above laser annealing equipment provided by the embodiment of the present invention, as shown in FIG. 2 , the distances between the gas diffusion holes 1012 at both ends of each row and the center of the end surface of the laser exit slit 1011 are the same. It can be understood that the setting boundary of the gas diffusion hole 1012 is centered on the center of the end face of the laser exit slit 1011, and between the center of the end face of the laser exit slit 1011 and the far boundary of the bottom cover plate 101 in the laser scanning direction Y The distance is a circular arc with a radius (that is, the dotted arc line in the figure), so as to ensure that each row of gas diffusion holes 1012 on the bottom cover plate 201 is within this uniform boundary. In addition, by providing the gas diffusion holes 1012 only in the above boundary range, the pressure balance of the nitrogen atmosphere is realized.

Optionally, in the above-mentioned laser annealing equipment provided by the embodiment of the present invention, the gas diffusion hole 1012 is a tapered hole, and the wide angle of the tapered hole is 60°-120°, such as 60°, 70°, 80°, 90° , 100°, 110° and 120°, etc., so that the nitrogen atmosphere diffused to the surface of the amorphous silicon film is relatively uniform.

Optionally, in the above-mentioned laser annealing equipment provided by the embodiment of the present invention, as shown in FIG. 2 , the deoxidation chamber 001 further includes: a plurality of first oxygen detectors 1013, and the plurality of first oxygen detectors 1013 are respectively arranged in The boundary of the region where the gas diffusion holes 1012 are located at both ends of the laser exit slit 1011 in the extending direction, and the intersection of the two ends and the center of the laser exit slit 1011 and the boundary of the bottom cover 101 .

As shown in Figure 2, since the oxygen environment on both sides of the extending direction of the laser emitting slit 1011 is similar, it can only be arranged on one side of the extending direction of the laser emitting slit 1011 (i.e. the two ends of the laser emitting slit 1011, the three vertical lines in the center) A first oxygen detector 1013 is set at the intersection with a boundary of the bottom cover plate 101; and the oxygen environment at both ends of the laser exit slit 1011 is very different, so the first oxygen detector 1013 needs to be set at both ends of the laser exit slit 1011. Oxygen detector 1013, to monitor the oxygen concentration reasonably and effectively.

Optionally, in the above-mentioned laser annealing equipment provided by the embodiment of the present invention, as shown in FIG. 4 , the annealing chamber 002 further includes: a plurality of first nitrogen diffusers (N ₂ Diffuser) 202 located under the carrying platform 201, And a plurality of second nitrogen diffusers 203 located below the plane where each first nitrogen diffuser 202 is located; Specifically, FIG. 4 shows six first nitrogen diffusers 202 and six second nitrogen diffusers 203;

The orthographic projections of a plurality of second nitrogen diffusers 203 on the bottom surface of the annealing chamber 002 are respectively located on the bottom surface of the annealing chamber 002 and on the side perpendicular to the plane where the gate door of the annealing chamber 002 is located (as shown by the black thick line in the figure). ends and center;

The orthographic projections of the plurality of first nitrogen diffusers 202 on the bottom surface of the annealing chamber 002 are respectively located at the centers of the orthographic projections of the adjacent second nitrogen diffusers 203 on the bottom surface of the annealing chamber 002;

The distance B between the plane where each first nitrogen diffuser 202 is located and the bottom surface of the annealing chamber 002 is twice the distance A between the plane where each second nitrogen diffuser 203 is located and the bottom surface of the annealing chamber 002 .

The first nitrogen gas diffuser 202 and the second nitrogen gas diffuser 203 are evenly distributed in the annealing chamber 002, which can effectively maintain the stability of nitrogen ambient pressure and atmosphere in the annealing chamber 002, and ensure the stable annealing process. Moreover, in order to ensure that the nitrogen content in the annealing chamber 002 is as consistent as possible, and the internal pressure remains the same at all positions, the distance B between the plane where each first nitrogen diffuser 202 is located and the bottom surface of the annealing chamber 002 is specifically set, which is the distance B between each second nitrogen diffuser 202. The distance A between the plane where 203 is located and the bottom surface of the annealing chamber 002 just makes the space below the carrying platform 201 divided into upper and lower parts with equal volumes. The rate (N ₂ flow rate) diffuses nitrogen uniformly to the upper part with equal volume at the same time, and the second nitrogen diffuser 203 is similar to ensure that the lower part has the same nitrogen diffusion rate. In addition, the nitrogen flow rates of the upper part and the lower part can be adjusted independently during specific implementation.

It should be noted that the dimensions in the accompanying drawing 4 do not reflect the actual scale, and are only intended to schematically illustrate the content of the present invention. In the actual product, the height of the space above the carrier table 201 (i.e. the difference between C and B) is about 5 mm, while the height C of the entire annealing chamber 002 can reach several meters. Therefore, the first nitrogen diffuser 202 and the second nitrogen diffuser 203 divides the space below the loading platform 201 into upper and lower parts of equal volume to ensure that the nitrogen content in each position in the upper and lower parts is as consistent as possible, which is equivalent to maintaining the stability of the nitrogen atmosphere in the large environment of the entire annealing chamber 002.

Optionally, in the above-mentioned laser annealing equipment provided by the embodiment of the present invention, as shown in FIG. 4, the annealing chamber 002 further includes: a plurality of second oxygen detectors 204; specifically, FIG. 4 shows four Dioxygen detector 204;

The orthographic projections of part of the second oxygen detectors 204 on the bottom surface of the annealing chamber 002 are located at both ends of the bottom surface of the annealing chamber 002 and the plane where the door of the annealing chamber 002 intersects;

The orthographic projections of the rest of the second oxygen detector 204 on the bottom surface of the annealing chamber 002 are located at both ends of the intersecting side of the side opposite to the door of the annealing chamber 002 in the bottom surface of the annealing chamber 002;

The plane where the plurality of second oxygen detectors 204 are located is the interface between each of the first nitrogen gas diffusers 202 and each of the second nitrogen gas diffusers 203 (as shown by the dotted line box in the figure).

The arrangement of multiple second oxygen detectors 204 can monitor the oxygen concentration in the annealing chamber 002 rationally by block. Considering that when the substrate with amorphous silicon film is replaced (Exchange load) or unloaded (unload), the internal atmosphere of annealing chamber 002 has the greatest degree of disturbance, and the block supervision and control method is adopted to improve the sensitivity of the atmosphere perception and achieve atmosphere stability. Rapid recovery. For example, during the door opening of the annealing chamber 002, in order to keep the gas flow stable and avoid too much oxygen entering the annealing chamber 002, it is necessary to increase the nitrogen flow (N ₂ Purge) in this area; after closing the door, it is also necessary to ensure the oxygen in the annealing chamber 002 The concentration quickly returns to the steady state of the process, and the module in this area automatically executes the command to increase the nitrogen flow. Specifically, the process of automatically executing the command to increase the nitrogen flow rate is an existing technology, and details are not described here.

Optionally, in the above-mentioned laser annealing equipment provided in the embodiment of the present invention, as shown in FIG. They are respectively located at the centers of multiple boundaries on the bottom surface of the annealing chamber 002 .

In the related art, only one nitrogen diffuser is installed in the four corners of the annealing chamber 002, but in the embodiment of the present invention, at least 12 nitrogen diffusers are arranged in layers. In order to speed up the exhaust process and maintain the air pressure balance during the exhaust process, In this embodiment, an exhaust port is respectively provided at the central positions of multiple boundaries on the bottom surface of the annealing chamber 002 .

It can be seen from the above description that in the above embodiments provided by the present invention, the innovative design of the laser annealing equipment is mainly carried out from the following two aspects, which can effectively improve the stability of the annealing process atmosphere. Firstly, a plurality of gas diffusion holes 1012 are designed on the bottom cover plate 101 (also called nitrogen diffuser plate, N ₂ diffuser Plate) of the deoxidation chamber 001, so as to keep the oxygen away from the laser emitting crystallization position, which can effectively avoid the impact of oxygen on the amorphous silicon crystallization. interference; secondly, better rationalize the design of the annealing chamber 002, propose a nitrogen flow layer (N ₂ Flow) diffusion method, control the oxygen concentration in layers, in order to achieve the effect of gas atmosphere stability, and optimize the oxygen concentration monitoring method at the same time. The block regulator control adjustment method improves the sensitivity to atmosphere perception, which can realize the rapid recovery of atmosphere stability. Through the above methods, the amorphous silicon crystallization effect is better, the electrical characteristics of the transistor are better, and the product yield rate is improved.

The above-mentioned laser annealing equipment provided by the embodiment of the present invention includes: a deoxidation chamber, an excimer laser generator located above the deoxidation chamber, and an annealing chamber located below the deoxidation chamber, wherein the annealing chamber includes: a carrying platform, which is used for Carrying a substrate with an amorphous silicon film; a deoxidation chamber, including: a bottom cover plate, an annealing window, and a nitrogen delivery pipe; a bottom cover plate, including: a laser exit slit, and a plurality of gas diffusion holes distributed around the laser exit slit The nitrogen gas provided by the nitrogen delivery pipe fills the deoxidation chamber and diffuses to the carrying platform through the laser exit slit and each gas diffusion hole; the laser emitted by the excimer laser generator is directed to the carrying platform through the annealing window and the laser exit slit in turn. By adding a plurality of gas diffusion holes around the laser exit slit, the nitrogen atmosphere purged from the laser exit slit and each gas diffusion hole to the surface of the carrier is relatively uniform, thus ensuring that the laser irradiation at the laser exit slit The melting and recrystallization area on the amorphous silicon film is in a pure nitrogen environment without oxygen interference, which improves the crystallization quality and thus improves the product yield.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (9)

1. A laser annealing apparatus, comprising: a deoxidizing chamber, an excimer laser generator positioned above the deoxidizing chamber, and an annealing chamber positioned below the deoxidizing chamber, wherein,

the annealing chamber includes: a carrying table for carrying a substrate having an amorphous silicon film;

the deoxidizing chamber includes: the bottom cover plate, the annealing window and the nitrogen conveying pipe;

the bottom cover plate includes: a laser emission slit, and a plurality of gas diffusion holes distributed around the laser emission slit, wherein in the extending direction of the laser emission slit, the gas diffusion holes are arranged in a plurality of rows, and the row spacing between the gas diffusion holes in each row increases with the distance between the gas diffusion holes and the laser emission slit;

the nitrogen gas provided by the nitrogen gas conveying pipe fills the deoxidizing chamber and is diffused to the bearing table through the laser emergent slit and each gas diffusion hole;

and laser emitted by the excimer laser generator is emitted to the bearing table through the annealing window and the laser emergent slit in sequence.

2. The laser annealing apparatus according to claim 1, wherein each of said gas diffusion holes of adjacent rows are offset from each other.

3. The laser annealing apparatus according to claim 1, wherein distances between adjacent ones of the gas diffusion holes in each row are the same.

4. The laser annealing apparatus according to claim 1, wherein a distance between the gas diffusion holes at both ends in each row and a center of the laser exit slit end face is the same.

5. The laser annealing apparatus according to claim 1, wherein the gas diffusion hole is a tapered hole having a wide angle of 60 ° to 120 °.

6. The laser annealing apparatus according to any one of claims 1 to 5, wherein said deoxidizing chamber further comprises: the first oxygen detectors are respectively arranged at the boundary of the area where the gas diffusion holes are located at the two ends of the extending direction of the laser emergent slit, and at the intersection of the three perpendicular lines at the two ends and the center of the laser emergent slit and the boundary of the bottom cover plate.

7. The laser annealing apparatus according to any one of claims 1 to 5, wherein said annealing chamber further comprises: a plurality of first nitrogen diffusers located below the carrier table, and a plurality of second nitrogen diffusers located below a plane in which each of the first nitrogen diffusers is located;

orthographic projections of the second nitrogen diffusers on the bottom surface of the annealing chamber are respectively positioned at two ends and the center of the vertical side of the bottom surface of the annealing chamber, which is opposite to the plane of the annealing chamber;

orthographic projections of the first nitrogen diffusers on the bottom surface of the annealing chamber are respectively positioned at the centers of orthographic projection connecting lines of the adjacent second nitrogen diffusers on the bottom surface of the annealing chamber;

the distance between the plane of each first nitrogen diffuser and the bottom surface of the annealing chamber is twice the distance between the plane of each second nitrogen diffuser and the bottom surface of the annealing chamber.

8. The laser annealing apparatus according to claim 7, wherein said annealing chamber further comprises: a plurality of second oxygen detectors;

wherein the orthographic projections of part of the second oxygen detectors on the bottom surface of the annealing chamber are respectively positioned at two ends of the bottom surface of the annealing chamber at the edge intersecting with the plane of the annealing chamber door;

the other parts of the second oxygen detectors are orthographic projected on the bottom surface of the annealing chamber and are respectively positioned at two ends of the intersecting edge of the side surface of the bottom surface of the annealing chamber opposite to the door of the annealing chamber;

the plane of the plurality of second oxygen detectors is an interface between each of the first nitrogen diffusers and each of the second nitrogen diffusers.

9. The laser annealing apparatus according to claim 7, wherein said annealing chamber further comprises: and a plurality of exhaust ports positioned on the bottom surface of the annealing chamber, the plurality of exhaust ports being respectively positioned at the centers of a plurality of boundaries of the bottom surface of the annealing chamber.