Nitrogen protection device and laser annealing equipment

Abstract

The application belongs to the technical field of display device manufacturing, and discloses a nitrogen protection device and a laser annealing device. The nitrogen protection device comprises a nozzle mechanism and a recovery mechanism. The nozzle mechanism is arranged above the recovery mechanism. The nozzle mechanism is used for downwardly spraying nitrogen. The recovery mechanism is used for extracting air to form an air curtain between the nozzle mechanism and the recovery mechanism. The air curtain can effectively block the influence of the external air flow field on the inside, reduce the existence of vortex, and ensure the stable supply of the nitrogen atmosphere. Meanwhile, a very high vacuum degree can be formed between the nozzle mechanism and the recovery mechanism, thereby effectively reducing the oxygen concentration. According to test verification, the oxygen concentration can be controlled to be less than 100 ppm or even lower.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display device manufacturing, in particular to a nitrogen protection device and a laser annealing device. BACKGROUND

[0002] In recent years, with the development of semiconductor technology, the feature size of wafers has entered the nanometer era, which also poses new challenges to semiconductor manufacturing technology. Therefore, semiconductor manufacturing technology begins to widely use laser annealing technology to meet the process needs. Laser annealing is to provide a laser light source by a laser pulse device, and the laser light source is processed into an elongated laser by an optical processing system (i.e. a series of lenses), and the film layer on the wafer is irradiated by the laser. The purpose of using laser annealing technology on the wafer is to crystallize or improve the crystallinity, and to convert amorphous material into polycrystalline or single crystal state, so that after ion implantation, the impurities are arranged and combined in order with the atoms in the film layer, thereby improving the electrical properties of the material on the chip unit of the wafer.

[0003] In order to prevent the formation of high-resistance silicon dioxide and nickel oxide components and other impurities in the oxygen atmosphere during annealing, it is required that the laser annealing operation must be carried out under the protection of inert gases such as nitrogen, thereby improving the performance of laser annealing. The existing nitrogen protection device places the wafer in a sealed cavity, and the air flow in the cavity has a great influence on the flow field near the laser head, which makes it difficult to stably control the nitrogen atmosphere in this area. If the influence is to be weakened, the sealing performance of the sealing structure of the cavity needs to be improved, which leads to a complex sealing structure and increased cost, or the supply amount of nitrogen gas needs to be increased, which will inevitably increase the cost of nitrogen gas and increase the risk of broken pieces due to the increased nitrogen gas flow rate on the surface of the wafer.

[0004] Therefore, it is urgent to provide a nitrogen protection device and a laser annealing device to solve the above technical problems in the prior art. SUMMARY

[0005] The present application aims to provide a nitrogen protection device and a laser annealing device,

[0006] To achieve the above purpose, the present application adopts the following technical solutions:

[0007] A nitrogen protection device, comprising a nozzle mechanism and a recovery mechanism, the nozzle mechanism is arranged above the recovery mechanism, the nozzle mechanism is used for downwardly spraying nitrogen, and the recovery mechanism is used for extracting air to form an air curtain between the nozzle mechanism and the recovery mechanism.

[0008] As a preferred technical solution of the above-mentioned nitrogen protection device, the nozzle mechanism comprises: a nozzle body in the shape of a ring and having a hollow air inlet cavity, and a gas outlet opening communicated with the air inlet cavity is formed on the end face of the nozzle body.

[0009] As the preferred technical scheme of the above-mentioned nitrogen protection device, the nozzle mechanism further comprises: an air inlet connector arranged on the outer circumferential side wall of the nozzle body and in communication with the air inlet cavity, the air inlet connector being used for conveying the nitrogen into the air inlet cavity.

[0010] As the preferred technical scheme of the above-mentioned nitrogen protection device, further comprising: a gas supply device in communication with the air inlet connector through an air inlet pipeline.

[0011] As the preferred technical scheme of the above-mentioned nitrogen protection device, the air injection ports are arranged in multiple and uniformly distributed in a ring shape on the end surface of the nozzle body.

[0012] As the preferred technical scheme of the above-mentioned nitrogen protection device, the air injection ports are arranged on the lower end surface of the nozzle body perpendicular to the vertical direction.

[0013] As the preferred technical scheme of the above-mentioned nitrogen protection device, an inclined transition slope is arranged between the lower end surface and the inner annular surface of the nozzle body, the transition slope being inclined from the direction of the inner annular surface towards the lower end surface, and the air injection ports are arranged on the transition slope.

[0014] As the preferred technical scheme of the above-mentioned nitrogen protection device, the recovery mechanism is in a ring shape and has a hollow recovery cavity, and the air inlet ports in communication with the recovery cavity are arranged on the inner circumferential side wall of the recovery mechanism.

[0015] As the preferred technical scheme of the above-mentioned nitrogen protection device, the axis direction of the air inlet ports is perpendicular to the axis direction of the air injection ports.

[0016] As the preferred technical scheme of the above-mentioned nitrogen protection device, the outer diameter of the nozzle mechanism is greater than the outer diameter of the recovery mechanism.

[0017] As the preferred technical scheme of the above-mentioned nitrogen protection device, further comprising: a vacuumizing device in communication with the recovery cavity through an air outlet pipeline.

[0018] To achieve the above-mentioned purpose, the application further provides a laser annealing device comprising a laser head and the above-mentioned nitrogen protection device, the laser head being arranged above the nozzle mechanism, and the lower surface of the recovery mechanism being arranged higher than the annealing surface of the silicon wafer.

[0019] As the preferred technical scheme of the above-mentioned nitrogen protection device, the laser head, the nozzle mechanism and the recovery mechanism are arranged concentrically.

[0020] Compared with the prior art, the application has the following advantages and beneficial effects:

[0021] The nitrogen protection device provided by the application comprises a nozzle mechanism and a recovery mechanism, the nozzle mechanism is arranged above the recovery mechanism, the nozzle mechanism is used for spraying nitrogen downward, and the recovery mechanism is used for extracting air to form an air curtain between the nozzle mechanism and the recovery mechanism. The air curtain can effectively block the influence of the air flow field outside the air curtain on the inside of the air curtain, reduce the existence of vortex, and ensure stable supply of the nitrogen atmosphere; meanwhile, a very high vacuum degree can be formed between the nozzle mechanism and the recovery mechanism, so that the oxygen concentration is effectively reduced, and the oxygen concentration can be controlled to be less than 100 ppm or even lower through test verification.

[0022] The laser annealing device provided by the application comprises the nitrogen protection device, a laser head is arranged above the nozzle mechanism, and the lower surface of the recovery mechanism is arranged to be higher than the annealing surface of the silicon wafer. The laser annealing device provided by the application can ensure stable control of the nitrogen atmosphere in the laser irradiation area, effectively establish and improve the vacuum degree between the laser head and the silicon wafer, thereby greatly reducing the oxygen concentration between the laser head and the annealing surface of the silicon wafer, and improving the laser annealing performance.

[0023] Additional aspects and advantages of the application will be described in part below, will become apparent from the following description, or will be learned by practicing the application. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a structure schematic diagram of the laser annealing device provided by the embodiment of the application;

[0025] Figure 2 is a structure schematic diagram of the nozzle mechanism of the nitrogen protection device provided by the embodiment of the application;

[0026] Figure 3 is a structure schematic diagram of the recovery mechanism of the nitrogen protection device provided by the embodiment of the application.

[0027] The signs in the figure are as follows:

[0028] 1, nozzle mechanism; 11, nozzle body; 111, air outlet; 12, lower end surface; 13, transition inclined surface;

[0029] 2, recovery mechanism; 21, air inlet;

[0030] 3, gas supply device;

[0031] 4, vacuumizing device;

[0032] 100, laser head. DETAILED DESCRIPTION

[0033] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application.

[0034] In the description of the present application, it should be noted that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", etc. are only for the purpose of description, and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0035] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0036] The present embodiment discloses a nitrogen protection device applied to a laser annealing equipment, which is used for manufacturing a nitrogen atmosphere for a laser annealing process and ensuring the nitrogen atmosphere index of a silicon wafer surface. As shown in the figure, the nitrogen protection device comprises a nozzle mechanism 1 and a recovery mechanism 2, the nozzle mechanism 1 is arranged above the recovery mechanism 2, the nozzle mechanism 1 is used for downwardly spraying nitrogen, and the recovery mechanism 2 is used for extracting air pressed down by the nitrogen to form an air curtain between the nozzle mechanism 1 and the recovery mechanism 2. Figure 1

[0037] The air curtain can effectively block the influence of the external air flow field on the inside, reduce the existence of vortex, and ensure the stable supply of the nitrogen atmosphere; at the same time, a very high vacuum degree can be formed between the nozzle mechanism 1 and the recovery mechanism 2, so as to effectively reduce the oxygen concentration. Through test verification, the oxygen concentration can be controlled within 100 ppm or even lower.

[0038] Further, as shown in the figure, Figure 2 ​As shown, the nozzle mechanism 1 comprises a nozzle body 11, which is annular, specifically circular annular, has a hollow air inlet cavity, and has a jet port 111 on an end face thereof, which is connected with the air inlet cavity and is used for downwardly spraying nitrogen. Preferably, the gas spraying direction of the jet port 111 is vertically downward. Correspondingly, the jet port 111 is arranged on a lower end face 12 of the nozzle body 11, which is perpendicular to the vertical direction. In another alternative embodiment, an inclined transition slope 13 is arranged between the lower end face 12 and the inner annular face of the nozzle body 11, the transition slope 13 is inclined from the inner annular face toward the lower end face 12, and the jet port 111 is arranged on the transition slope 13. The inclination angle is only required to be such that the jet direction of the jet port 111 on the transition slope 13 is downward and inward, and the specific inclination angle is not limited in the embodiment, for example, the included angle with the horizontal plane can be not greater than 15°. By additionally arranging the jet port 111 on the transition slope 13, the number of jet ports 111 on the nozzle body 11 is increased, the nitrogen ventilation amount is improved, and the oxygen concentration is better reduced.

[0039] Preferably, the upper half of the inner annular face of the nozzle body 11 is also provided with the jet port 111, and the nitrogen concentration is further improved.

[0040] The nozzle mechanism 1 further comprises an air inlet connector (not shown in the figure), which is arranged on the outer peripheral side wall of the nozzle body 11 and is connected with the air inlet cavity, and is used for conveying nitrogen into the air inlet cavity. Alternatively, the air inlet connector is arranged in four and symmetrically arranged on the nozzle body 11 in two groups. This structure can improve the uniformity of nitrogen ventilation, thereby improving the uniformity of nitrogen spraying. In other embodiments, the number of air inlet connectors can also be two, three or more than four, which can be designed according to the actual situation. The arrangement mode of the air inlet connector can also be equidistantly distributed along the circumferential direction of the nozzle body 11.

[0041] Preferably, the jet port 111 is arranged in multiple and annularly and uniformly distributed on the above-mentioned faces of the nozzle body 11, and the jet uniformity is improved. Further preferably, the lower end face 12 and the transition slope 13 of the nozzle body 11 are both provided with inner and outer two circles of jet ports 111, and the nitrogen spraying amount is improved.

[0042] The nitrogen protection device in the embodiment further comprises a gas supply device 3, which is connected with the air inlet connector through an air inlet pipeline and is used for providing nitrogen for the nozzle mechanism 1. It should be noted that the gas supply device 3 not only serves as a nitrogen source, but also purifies, filters and the like the nitrogen, and the treated nitrogen enters the jet mechanism through the air inlet pipeline.

[0043] As Figure 3As shown, the recovery mechanism 2 is annular, has a hollow recovery cavity, and the inner circumferential wall of the recovery mechanism 2 is provided with air inlets 21 which are in communication with the recovery cavity. The air under the nitrogen pressure enters the recovery cavity through the air inlets 21.

[0044] Optionally, the outer ring of the recovery mechanism 2 is a circular ring, and the inner ring is a rectangular ring. The inner circumferential wall of the rectangular ring is uniformly provided with a plurality of air inlets 21. In this structure, the axis direction of the air inlets 21 is perpendicular to the axial direction of the air injection port 111, which can effectively reduce the vortex formed by the nitrogen injection of the nozzle mechanism 1, and ensure the stable supply of nitrogen.

[0045] Preferably, the air inlets 21 are arranged on the lower half of the inner circumferential wall of the rectangular ring of the recovery mechanism 2, so as to ensure that the air under the nitrogen pressure can be completely recovered by the recovery mechanism 2. Further preferably, the air inlets 21 are arranged in two rows, which can improve the air intake. The recovery effect of the polyurethane ring is better, which is beneficial to quickly extract air. Preferably, the rectangular ring is a square ring.

[0046] In order to ensure the coverage range of the air curtain, as shown, Figure 1 The outer diameter of the nozzle mechanism 1 is greater than the outer diameter of the recovery mechanism 2, so that the horizontal projection of the nozzle mechanism 1 is greater than the horizontal projection of the recovery mechanism 2. In this way, the gas flow field in the internal region of the nozzle mechanism 1 is controllable and relatively stable.

[0047] Since the processing cost of nitrogen is high, the nozzle mechanism 1 and the recovery mechanism 2 are arranged in an upper-lower opposite manner, which can save the amount of nitrogen, quickly establish the air curtain, and form a good nitrogen atmosphere.

[0048] The nitrogen protection device in the embodiment further comprises a vacuum pumping device 4 which is in communication with the recovery cavity through a gas pumping pipeline and is used to pump out the air in the recovery cavity, so as to quickly and effectively establish the air curtain and maintain and improve the vacuum degree. It should be noted that the vacuum pumping device 4 is a conventional device in the prior art, which will not be described here.

[0049] The embodiment further provides a laser annealing device which comprises a laser head 100 and the above-mentioned nitrogen protection device. The laser head 100 is arranged above the nozzle mechanism 1, the silicon wafer is at least partially located in the rectangular ring of the recovery mechanism 2, and the lower surface of the recovery mechanism 2 is higher than the annealing surface of the silicon wafer. Since the laser annealing device is provided with the above-mentioned nitrogen protection device, the nitrogen atmosphere in the laser irradiation region can be stably controlled, the vacuum degree between the laser head 100 and the silicon wafer can be effectively established and improved, the oxygen concentration between the laser head 100 and the annealing surface of the silicon wafer can be greatly reduced, and the laser annealing performance can be improved.

[0050] Optionally, the laser head 100, the nozzle mechanism 1 and the recovery mechanism 2 are concentrically arranged to ensure the stable control of the atmosphere of the laser irradiation area by the air curtain and reduce the oxygen concentration between the laser head 100 and the silicon wafer. Further preferably, the vertical distance between the nozzle mechanism 1 and the recovery mechanism 2 is not greater than 25 mm, and the lower surface of the recovery mechanism 2 is not higher than the annealing surface of the silicon wafer by more than 3 mm. It has been verified by experiments that the oxygen concentration on the laser annealing surface, i.e. the upper surface of the silicon wafer, is related to the nitrogen flow rate and the distance between the lower surface of the recovery mechanism 2 and the annealing surface of the silicon wafer. In theory, the smaller the distance and the nitrogen flow rate, the lower the oxygen concentration. However, considering the actual processing and the interference between parts, the distance should not be too small. Therefore, the distance is limited to within 3 mm, which is more ideal.

[0051] Further optionally, since the laser spot is generally less than 5 mm, the side length of the square ring of the recovery mechanism 2 is designed to be about 10 mm, and the specific size can be designed according to the actual situation.

[0052] Obviously, the above embodiments of the present application are only examples for clear illustration of the present application, and are not intended to limit the embodiments of the present application. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, it is not necessary and impossible to exhaust all the embodiments. Any modification, equivalent replacement and improvement within the spirit and principle of the present application shall be included in the protection scope of the claims of the present application.

Claims

1. A nitrogen protection device, characterized in that, The nitrogen protection device includes a nozzle mechanism (1) and a recovery mechanism (2). The nozzle mechanism (1) is located above the recovery mechanism (2). The nozzle mechanism (1) is used to spray nitrogen downwards, and the recovery mechanism (2) is used to extract air to form an air curtain between the nozzle mechanism (1) and the recovery mechanism (2). The nozzle mechanism (1) includes: The nozzle body (11) is annular and has a hollow air inlet chamber. An air jet port (111) communicating with the air inlet chamber is provided on the end face of the nozzle body (11). The air jet port (111) is used to spray the nitrogen gas downward. The jet nozzles (111) are provided in multiple forms and are evenly distributed in a ring on the end face of the nozzle body (11); The nozzle body (11) has the air jet (111) provided on the lower end face (12) perpendicular to the vertical direction. An inclined transition slope (13) is provided between the lower end face (12) and the inner annular surface of the nozzle body (11). The transition slope (13) is inclined from the inner annular surface toward the lower end face (12), and the jet nozzle (111) is provided on the transition slope (13).

2. The nitrogen protection device according to claim 1, characterized in that, The nozzle mechanism (1) further includes: An air inlet connector is disposed on the outer peripheral sidewall of the nozzle body (11) and communicates with the air inlet chamber. The air inlet connector is used to deliver the nitrogen gas into the air inlet chamber.

3. The nitrogen protection device according to claim 2, characterized in that, Also includes: The air supply device (3) is connected to the air inlet connector through an air inlet pipe.

4. The nitrogen protection device according to claim 1, characterized in that, The recycling mechanism (2) is annular and has a hollow recycling cavity. An air inlet (21) communicating with the recycling cavity is provided on the inner peripheral side wall of the recycling mechanism (2).

5. The nitrogen protection device according to claim 4, characterized in that, The axial direction of the air inlet (21) is perpendicular to the axial direction of the jet outlet (111).

6. The nitrogen protection device according to claim 4, characterized in that, The outer diameter of the nozzle mechanism (1) is larger than the outer diameter of the recovery mechanism (2).

7. The nitrogen protection device according to claim 4, characterized in that, Also includes: A vacuum pumping device (4) is connected to the recovery chamber via a vacuum pipe.

8. A laser annealing apparatus, comprising a laser head (100), characterized in that, The laser annealing equipment further includes a nitrogen protection device as described in any one of claims 1-7, wherein the laser head (100) is disposed above the nozzle mechanism (1), and the lower surface of the recovery mechanism (2) is disposed above the annealing surface of the silicon wafer.

9. The laser annealing equipment according to claim 8, characterized in that, The laser head (100), the nozzle mechanism (1), and the recovery mechanism (2) are arranged concentrically.

Images