Blazed grating manufacturing method, blazed grating and laser

Abstract

The invention discloses a blazed grating manufacturing method, a blazed grating and a laser, the blazed grating manufacturing method comprises the steps that a substrate is etched to obtain a plurality of side walls and a plurality of grooves, the side walls extend in a first direction, the side walls are arranged at intervals in a second direction, the second direction is perpendicular to the first direction, and the grooves are formed in the first direction; a groove is arranged between any two adjacent side walls, and each side wall is provided with a first side surface and a second side surface which are arranged along a second direction. And filling the groove with a first photoresist. And configuring a third direction of the substrate to be parallel to the direction of the exposure light beam, and exposing the first photoresist, the third direction being a direction in which the top edge of the second side surface points to the bottom edge of the first side surface in the same groove. And developing the first photoresist to obtain a blazed surface. And etching each side wall to obtain a plurality of connecting surfaces. Through the mode, the blazed grating with any blazed angle and vertex angle can be obtained without customizing the monotectic orientation silicon substrate.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of grating technology, and in particular to a blazed grating manufacturing method, a blazed grating and a laser. Background Art

[0002] Blazed grating is an important optical element with a periodic sawtooth structure on the substrate surface. Its most important application is as a spectroscopic component. Due to its miniaturization and high resolution, blazed grating has replaced prisms and become the core component of devices such as spectral instruments and external cavity tunable lasers. Summary of the invention

[0003] At present, the main technologies for making blazed gratings include mechanical scribing, holographic ion beam etching, and anisotropic etching. Taking the anisotropic etching method as an example, this method requires the customization of the polarized silicon substrate according to the blaze angle or vertex angle of the blazed grating, which is expensive to customize; and due to the line width limitation, this method has a high risk of a top platform, that is, the 90° vertex angle is difficult to be made into a sharp angle, thereby reducing the diffraction efficiency.

[0004] The embodiments of the present application provide a blazed grating manufacturing method, a blazed grating and a laser to improve the current situation of high cost due to customized polarized silicon substrate in the related art.

[0005] In a first aspect, an embodiment of the present application provides a method for manufacturing a blazed grating, comprising: etching a substrate to obtain a plurality of side walls and a plurality of grooves, wherein the side walls extend along a first direction, and each of the side walls is arranged at intervals along a second direction, the second direction is perpendicular to the first direction, and there is a groove between any two adjacent side walls, and the side walls have a first side surface and a second side surface arranged along the second direction, and the second direction is a direction from the first side surface to the second side surface; filling the groove with a first photoresist; configuring a third direction of the substrate to be parallel to a direction of an exposure light beam, and exposing the first photoresist, wherein the third direction is a direction from the top edge of the second side surface in the same groove to the bottom edge of the first side surface; developing the first photoresist to obtain a blazed surface; etching each of the side walls to obtain a plurality of connecting surfaces, wherein the bottom edge of the connecting surface is the bottom edge of the first side surface, and the top edge of the connecting surface is the top edge of the second side surface.

[0006] Through the above-mentioned manufacturing process, a blazed grating with any blaze angle and vertex angle can be obtained, and there is no need to customize the polarized silicon substrate. Compared with the single crystal silicon anisotropic etching method in the related art, which requires the customization of the polarized silicon substrate, the method for making a blazed grating provided by the present application has lower requirements on the substrate and enriches the method for making a blazed grating. At the same time, since the embodiment of the present application does not use wet etching, it is more conducive to forming a sharp vertex angle, which can reduce the risk of the top being a plane.

[0007] In one or more embodiments, etching the substrate to obtain a plurality of side walls and a plurality of grooves includes: spin coating a second photoresist on the surface of the substrate; exposing and developing the second photoresist to obtain a plurality of masks and exposing areas of the substrate outside the masks, wherein the masks extend along the first direction and the masks are arranged at intervals along the second direction; etching the exposed areas of the substrate to obtain the plurality of side walls and the plurality of grooves; and removing the masks.

[0008] In one or more embodiments, filling the groove with the first photoresist includes: spin coating the first photoresist on the surface of the substrate until the groove is filled with the first photoresist.

[0009] In one or more embodiments, etching each of the side walls to obtain a plurality of connecting surfaces includes: configuring the substrate so that the blazing surface is parallel to the emission direction of the ion beam, and the emission direction of the ion beam is perpendicular to the bottom edge of the first side surface; emitting an ion beam, and controlling the substrate to rotate around a preset axis to plasma-etch the side walls and form the connecting surfaces, wherein the preset axis is parallel to the bottom edge of the first side surface.

[0010] In one or more embodiments, the included angle between the blazing surface and the upstream adjacent connecting surface is 90 degrees.

[0011] When the incident light is incident in a direction perpendicular to the blazing surface, by configuring the angle between the blazing surface and the upstream adjacent connecting surface to be 90 degrees, the incident light can be prevented from being blocked by the adjacent grating, which is beneficial to improving the diffraction efficiency of the blazing grating.

[0012] In one or more embodiments, after etching each of the side walls to obtain a plurality of connecting surfaces, the method further comprises: coating the shining surface and / or the connecting surface with an anti-reflection film; wherein the material of the anti-reflection film comprises gold or aluminum.

[0013] In a second aspect, an embodiment of the present application provides a blazed grating, wherein the blazed grating is manufactured by the method described above.

[0014] In a third aspect, an embodiment of the present application provides a laser, comprising: a semiconductor optical amplifier having a first output end and a second output end, the semiconductor optical amplifier being configured to output laser light via the first output end; and a scanning element, comprising a blazed grating and a driving unit, the blazed grating being used to receive the laser light and diffract it so that part of the laser light is directed toward the first output end and emitted from the second output end after gain through the semiconductor optical amplifier, the driving unit being used to drive the blazed grating to rotate; wherein the blazed grating is the blazed grating as described above.

[0015] By using a blazed grating as a beam splitter in a laser, the laser can have a wider tuning range and a higher output power, and the laser can also be used as a single-mode high-quality light source.

[0016] In one or more embodiments, the scanning element is a MEMS scanning element, and the MEMS scanning element includes: a fixed part, which is provided with a receiving groove; the blazed grating, which is arranged in the receiving groove; a torsion axis, which is respectively connected to the blazed grating and the fixed part, so that the blazed grating can rotate relative to the fixed part; and the driving unit, which is used to drive the blazed grating to rotate.

[0017] In one or more embodiments, the driving unit includes a magnet and a coil; one of the magnet and the coil is arranged on the side of the blazing grating away from the blazing surface, and the other is arranged outside the blazing grating, and the magnet and the coil are used to cooperate together to drive the blazing grating to rotate relative to the fixed part.

[0018] The beneficial effects of the present application are as follows: the method for manufacturing a blazed grating of the embodiment of the present application first etches a substrate to obtain a plurality of side walls and a plurality of grooves, then fills the grooves with a first photoresist, and then configures the third direction of the substrate to be parallel to the direction of the exposure beam, and exposes and develops the first photoresist, thereby obtaining a blazed surface and a blazed angle. Afterwards, each side wall is etched to obtain a plurality of connecting surfaces, wherein the bottom edge of the connecting surface is the bottom edge of the first side surface, and the top edge of the connecting surface is the top edge of the second side surface, and then the top angle can be obtained based on the angle between the connecting surface and the blazed surface. At this point, the manufacturing process of the blazed grating is realized.

[0019] Compared with the method of customizing the polarized silicon substrate in the anisotropic etching method of single crystal silicon, the manufacturing process provided by the embodiment of the present application does not require the customization of the polarized silicon substrate, and can obtain a blazed grating with any blaze angle and vertex angle; it can be seen that compared with the related art, the method of manufacturing the blazed grating provided by the present application has lower requirements on the substrate and enriches the manufacturing method of the blazed grating. In addition, the method does not use wet etching, which is more conducive to forming a sharp vertex angle and can reduce the risk of the top being a plane. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] One or more embodiments are exemplarily described by the figures in the corresponding drawings, and these exemplary descriptions are not intended to limit the embodiments. Elements with the same reference numerals in the drawings represent similar elements.

[0021] Figure 1 is a flow chart of a method for manufacturing a blazed grating provided in an embodiment of the present application;

[0022] Figure 2 These are four schematic diagrams of substrates provided in the embodiments of the present application;

[0023] Figure 3 is a schematic diagram of a substrate and a first photoresist in a process of forming a blazed grating provided by an embodiment of the present application;

[0024] Figure 4 The embodiment of this application provides Figure 1 A schematic diagram of an embodiment of step 15 shown in FIG.

[0025] Figure 5 are two schematic diagrams of a substrate and a first photoresist during etching of a sidewall provided in an embodiment of the present application;

[0026] Figure 6 The embodiment of this application provides Figure 1 A schematic diagram of an embodiment of step 11 shown in FIG.

[0027] Figure 7 is a schematic diagram of a substrate and a second photoresist in a process of forming a sidewall and a groove provided by an embodiment of the present application;

[0028] Figure 8 is a schematic diagram of a block diagram of a laser provided in an embodiment of the present application;

[0029] Fig. 9 It is a schematic diagram of the structure of the scanning element provided in an embodiment of the present application. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and in detail in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0031] It should be noted that, when an element is described as being “connected to” another element, it may be directly connected to the other element, or one or more intervening elements may exist therebetween.

[0032] In addition, the technical features involved in the various embodiments of the present application described below can be combined with each other as long as there is no structural conflict between them.

[0033] Please refer to Figure 1 , Figure 1 Flow chart of the method for manufacturing a blazed grating provided in an embodiment of the present application. Figure 1 As shown, the blazed grating manufacturing method comprises the following steps:

[0034] Step 11: Etch the substrate to obtain multiple side walls and multiple grooves, wherein the side walls extend along a first direction, the side walls are arranged at intervals along a second direction, the second direction is perpendicular to the first direction, there is a groove between any adjacent two side walls, the side walls have a first side surface and a second side surface arranged along the second direction, and the second direction is the direction from the first side surface to the second side surface.

[0035] Among them, in the fields of microelectronics manufacturing, semiconductor processing, nanotechnology and material science, "substrate" generally refers to the underlying material used to support and carry other material structures, such as silicon wafers, glass substrates or other materials. In the etching process, the substrate is a platform or substrate to which the etched material (such as the first photoresist in the embodiment of the present application) is attached. By etching the substrate, part of the material on the substrate surface can be removed, thereby forming a specific pattern or structure on the substrate.

[0036] Please refer to Figure 2 , Figure 2 Four different schematic diagrams of the substrate are shown as examples. Figure 2 Part (a1) shows a schematic diagram of the substrate 100 without any treatment; Figure 2 Part (a2) in FIG. 1 shows a view obtained by etching the substrate 100 to obtain five sidewalls and four grooves, and observed from the left front of the substrate 100; Figure 2 Part (a3) ​​in FIG. 1 shows a view obtained by etching the substrate 100 to obtain five sidewalls and four grooves, and observed from the right front of the substrate 100; Figure 2 Part (a4) in FIG. 1 shows a front view of the substrate 100 .

[0037] It is understandable that in this embodiment, the substrate 100 is taken as a rectangular parallelepiped before any processing, and in other embodiments, a substrate 100 of other shapes, such as a cube, etc., can also be used, and the embodiment of the present application does not make any specific limitation to this.

[0038] Secondly, this embodiment takes the example of etching the substrate 100 to obtain five sidewalls and four grooves, while in other embodiments, the substrate 100 may be etched to obtain other numbers of sidewalls and grooves, and the embodiment of the present application does not specifically limit this. For ease of description, the subsequent embodiments of the present application are described by taking the example of etching the substrate 100 to obtain five sidewalls and four grooves.

[0039] like Figure 2 As shown in parts (a2), (a3) ​​and (a4) of the figure, the substrate 100 is etched to obtain five side walls 101 and four grooves 102. The five side walls 101 all extend along a first direction, and the first direction is the positive or reverse direction of the Y axis shown in the figure. Specifically, the side wall 101 extends from the front of the substrate 100 along the positive direction of the Y axis, or the side wall 101 extends from the back of the substrate 100 along the reverse direction of the Y axis. The subsequent embodiments are described with the positive direction of the Y axis as the first direction. The side walls 101 are arranged at intervals along a second direction, and the second direction is the positive or reverse direction of the X axis shown in the figure. Specifically, starting from the leftmost side wall 101, the five side walls 101 are arranged in sequence along the positive direction of the X axis, or, starting from the rightmost side wall 101, the five side walls 101 are arranged in sequence along the negative direction of the X axis. The subsequent embodiments are described with the positive direction of the X axis as the second direction, and the Y axis is perpendicular to the X axis. There is a groove 102 between any two adjacent side walls 101. The side wall 101 has a first side surface 1011 and a second side surface 1012 arranged along a second direction, and the second direction is the direction from the first side surface 1011 to the second side surface 1012, that is, the positive direction of the X axis.

[0040] Step 12: Fill the groove with the first photoresist.

[0041] For details, please refer to Figure 3 , Figure 3 The front view of the substrate and the first photoresist during the process of forming the blazed grating is shown as an example. Figure 3 As shown in the (b1) part in the figure, first, the first photoresist 200 is filled into the groove 102. Wherein, photoresist is also called photoresist, and chemical changes will occur when it is exposed to the light of a specific wavelength, thereby forming a patterned structure in the developing process. Photoresist includes positive photoresist and negative photoresist. In the embodiment of the present application, taking the first photolithography machine 200 as a positive photoresist as an example, the first photoresist 200 can become soluble in developer in the exposed area, which means that the exposed part can be removed in the developing process, leaving the photoresist in the unexposed area.

[0042] In some embodiments, the specific implementation method of filling the groove 102 with the first photoresist 200 is: spin coating the first photoresist on the surface of the substrate until the groove is filled with the first photoresist. Specifically, using centrifugal force to evenly distribute the first photoresist 200 on the groove 102 until the groove 102 is filled with the first photoresist 200.

[0043] Step 13: configure the third direction of the substrate to be parallel to the direction of the exposure light beam, and expose the first photoresist, wherein the third direction is the direction in which the top edge of the second side surface in the same groove points to the bottom edge of the first side surface.

[0044] Step 14: Develop the first photoresist to obtain a shining surface.

[0045] After the first photoresist 200 is filled into the above-mentioned groove, the first photoresist 200 is sequentially exposed and developed to obtain a shining surface. In some embodiments, the first photoresist 200 is exposed by ultraviolet flooding exposure, and the first photoresist 200 is developed by a developer. Specifically, the direction of the exposure beam 300 (i.e., the ultraviolet beam) is configured to be parallel to the third direction, wherein the third direction is the direction from the top edge of the second side surface 1012 in the same groove 200 to the bottom edge of the first side surface 1011. For example, the direction corresponding to the curve S1 shown in the figure is the third direction, and the curve S1 is perpendicular to the top edge of the second side surface 1012 and the bottom edge of the first side surface 1011, respectively, and points from the top edge of the second side surface 1012 to the bottom edge of the first side surface 1011. When the exposure beam 300 is irradiated onto the first photoresist 200, it will trigger a photopolymerization reaction, so that the properties of the resist in the irradiated area change. Since the direction of the exposure beam 300 is parallel to the third direction, the first photoresist 200 is divided into two parts with the plane where the third direction is located as the dividing interface, one part (i.e. the upper half of the first photoresist 200) is the irradiated area, which will be eliminated after exposure and development; the other part (i.e. the lower half of the first photoresist 200) is the unirradiated area, which is retained and can form a smooth plane, that is, the shining surface, which can play a diffraction role.

[0046] like Figure 3 As shown in part (b2) of FIG. 1 , the first photoresist 200 is sequentially exposed and developed to obtain a blazing surface 201. The angle formed by the blazing surface 201 and the bottom edge of the groove 102 where it is located is the blazing angle of the blazing grating.

[0047] Step 15: Etching each sidewall to obtain a plurality of connection surfaces, wherein the bottom edge of the connection surface is the bottom edge of the first side surface, and the top edge of the connection surface is the top edge of the second side surface.

[0048] After obtaining the above-mentioned shining surface 201, Figure 3The sidewalls 101 in the structure shown in part (b2) are etched, such as by spin etching, to obtain a plurality of Figure 3 The connecting surface 1013 shown in the part (b3) in FIG. The angle between the connecting surface 1013 and the downstream adjacent blazing surface 201 is the vertex angle of the blazed grating, that is, the angle between the blazing surface 201 and the upstream adjacent connecting surface 1013 is the vertex angle of the blazed grating. So far, the manufacturing process of the blazed grating is realized, and the blazed grating with four periods is taken as an example, wherein each first photoresist 200 and the upstream adjacent sidewall 101 are one period, and the direction from upstream to downstream is the second direction.

[0049] It can be understood that in this embodiment, during the process of etching each side wall 101, the side wall 101 in the first period on the left is not blocked by any object, so the side wall 101 can be completely etched and the connecting surface 1013 cannot be formed. Based on this, in some embodiments, the first photoresist 200 in the first period and the substrate portion that receives the first period can be further removed. For example, the first photoresist 200 in the first period can be removed by a stripping process, and the substrate portion that receives the first period can be removed by etching, so as to obtain Figure 3 The blazed grating shown in part (b4) of FIG.

[0050] The above-mentioned blazed grating manufacturing method is described in detail below in combination with specific design parameters.

[0051] For example, in some embodiments, the required blazed grating has a period of 12.6 μm, a blazed angle of 15°, and a vertex angle of 90°. First, according to the geometric relationship of the required blazed grating, the first width (0.84 μm) of the sidewall 101, the second width (11.76 μm) of the groove 102, and the first depth (3.15 μm) can be determined. The specific calculation process is within the scope that can be easily understood by those skilled in the art and will not be repeated here. Then, the substrate 100 is etched to obtain a plurality of sidewalls 101 having a first width and a plurality of grooves 102 having a second width and a first depth. Thereafter, the first photoresist 200 is filled into the groove 102. Next, the substrate is tilted 75° so that the third direction of the substrate is in a vertical state, and the first photoresist 200 is sequentially exposed and developed in the vertical direction to obtain a blazed surface; the blazed angle formed by the blazed surface and the bottom edge of the corresponding groove 102 is the above-mentioned 15°. Finally, an etching process (such as a plasma etching process) is used to etch each sidewall 101 to obtain a plurality of connecting surfaces 1013; wherein, since the bottom edge of the connecting surface 1013 is the bottom edge of the first side surface, and the top edge of the connecting surface 1013 is the top edge of the second side surface, the angle (i.e., the top angle) between each connecting surface 1013 and the downstream adjacent blazing surface 201 is 90°. At this point, the manufacturing process of the blazed grating is completed.

[0052] It should be noted that, compared with the method of customizing the polarized silicon substrate in the single crystal silicon anisotropic etching method, the manufacturing process provided by the embodiment of the present application does not require the customization of the polarized silicon substrate, and can obtain a blazed grating with any blaze angle and vertex angle; it can be seen that compared with the related art, the method of manufacturing the blazed grating provided by the present application has lower requirements on the substrate and enriches the manufacturing method of the blazed grating. In addition, the method does not use wet etching, which is more conducive to forming a sharp vertex angle and can reduce the risk of the top being a plane.

[0053] The embodiment of the present application also provides a method for etching each side wall 101 to obtain a plurality of connection surfaces 1013. Specifically, Figure 4 As shown, the process of etching each sidewall in step 15 to obtain multiple connection surfaces includes the following steps:

[0054] Step 41: The substrate is configured so that the blazing surface is parallel to the emission direction of the ion beam, and the emission direction of the ion beam is perpendicular to the bottom edge of the first side surface.

[0055] Step 42: Emits an ion beam and controls the substrate to rotate around a preset axis to perform plasma etching on the sidewall and form a connecting surface, wherein the preset axis is parallel to the bottom edge of the first side surface.

[0056] Please refer to Figure 5 , Figure 5 The front view of the substrate and the first photoresist during the etching of the sidewall 101 is exemplarily shown.

[0057] like Figure 5As shown in part (c1), the emission direction of the ion beam 400 is the direction of its arrow. It can be seen that the emission direction of the ion beam 400 is parallel to the blazing surface 201 and perpendicular to the bottom edge of the first side. Wherein, the ion beam can be generated by a plasma source, such as an inductively coupled plasma (ICP) or a radio frequency (RF) plasma source, and then the ion beam is guided to the etching area through an appropriate focusing and guiding system. In the process of emitting the ion beam, the substrate 100 is controlled to rotate around a preset axis. Since the preset axis is parallel to the bottom edge of the first side, the direction of rotation is as shown by the arrow S2. Wherein, the preset axis is a pre-set rotation axis, which can be set based on the actual application scenario, and it only needs to satisfy that the preset axis is parallel to the bottom edge of the first side. During the rotation of the substrate 100, the ion beam 400 etches the side wall 101, and in this process, except for the first period, the side wall 101 of other periods will be gradually blocked by the upstream adjacent side wall 101 and the first photoresist 200 as the substrate 100 rotates, so as to gradually reduce the etching area of ​​the side wall 101, until the bottom edge of the groove 102 is parallel to the emission direction of the ion beam 400, thereby forming a connecting surface 1013. The angle formed between the connecting surface 1013 and the downstream adjacent blazing surface 201 is the required vertex angle of the blazing grating.

[0058] In some embodiments, the substrate 100 and the first photoresist 200 may be placed on a rotating platform so that the substrate 100 can be driven to rotate around a preset axis. Figure 5 As shown in part (c2), since the rotating platform S3 is placed horizontally, the substrate 100 can be tilted first, and the tilt angle θ is equal to the blaze angle. At this time, the blaze surface 201 is a horizontal plane, and the emission direction of the ion beam 400 is a horizontal direction. After the ion beam is emitted, the tilt angle θ is gradually reduced until the tilt angle θ is 0, and the ion beam is stopped. The etching is completed and a plurality of connecting surfaces 1013 are formed. In this embodiment, it is only necessary to set the tilt angle θ to be equal to the blaze angle to obtain the required apex angle of the blaze grating, which is easy to operate and helps to improve work efficiency. It should be noted here that since the emission direction of the plasma beam remains unchanged, the rotation speed of the substrate 100 driven by the rotating platform is controlled to obtain a flat inclined surface, that is, a connecting surface 1013. This method can be implemented in the field of chip etching and will not be elaborated here.

[0059] In some embodiments, the angle between the blazing surface and the upstream adjacent connecting surface is 90 degrees, that is, the vertex angle of the blazed grating is 90 degrees. When the incident light is incident in a direction perpendicular to the blazing surface, by configuring the vertex angle of the blazed grating to be 90 degrees, the incident light can be prevented from being blocked by the adjacent grating, which is beneficial to improving the diffraction efficiency of the blazed grating.

[0060] The present application also provides a method for etching the substrate 100 to obtain a plurality of sidewalls and a plurality of grooves, to supplement the above step 11. Specifically, Figure 6 As shown, the process of etching the substrate in step 11 to obtain a plurality of sidewalls and a plurality of grooves includes the following steps:

[0061] Step 61: Spin-coat a second photoresist on the surface of the substrate.

[0062] Step 62: exposing and developing the second photoresist to obtain a plurality of masks and exposing the area of ​​the substrate outside the masks, wherein the masks extend along the first direction and the masks are arranged at intervals along the second direction.

[0063] Step 63: Etching the exposed area of ​​the substrate to obtain a plurality of sidewalls and a plurality of grooves.

[0064] Step 64: Remove the mask.

[0065] Please refer to Figure 7 , Figure 7 The front view of the substrate and the second photoresist during the process of forming a plurality of sidewalls and a plurality of grooves is exemplarily shown. Figure 7 As shown in part (d1) of FIG. 1 , first, the second photoresist 500 is spin-coated on the surface of the substrate 100 to form a layer of the second photoresist 500 on the surface of the substrate 100. The second photoresist 500 is exemplified by a positive photoresist.

[0066] Next, the second photoresist 500 is exposed and developed. Figure 7 As shown in the part (d2) in FIG. 1 , a plurality of masks 501 can be obtained, and the area of ​​the substrate 100 between each two masks 501 is exposed. In some embodiments, an electron beam can be used to expose the target position in the second photoresist 500, and a developer can be used to develop the second photoresist 500 after the electron beam exposure, the target position in the second photoresist 500 is eliminated, and the area of ​​the substrate 100 receiving the target position is exposed, leaving only the unexposed portion, which forms the mask 501. Among them, the width of the target position is the width of the groove 102 formed subsequently, and the width of the mask 501 is the width of the sidewall 101 formed subsequently.

[0067] The exposed area of ​​the substrate 100 is etched to obtain a plurality of sidewalls 101 and a plurality of grooves 102, such as Figure 7 In some embodiments, a reactive ion etching (RIE) process is used to etch the exposed area of ​​the substrate 100, and the etching depth is the depth of the groove 102 to be formed subsequently.

[0068] Then, the mask 501 is partially removed to obtain a substrate 100 having a plurality of sidewalls 101 and a plurality of grooves 102. Figure 7 In some embodiments, the mask 501 is removed by a stripping process, for example, acetone or isopropyl alcohol is used to remove the mask 501 .

[0069] In some embodiments, after executing step 15, the following method step is further performed: coating the blazing surface and / or the connecting surface with an anti-reflection film.

[0070] The material of the anti-reflection film includes gold or aluminum. By forming one or more layers of anti-reflection films with specific optical properties on the blazed surface and / or the connecting surface, the reflectivity can be greatly increased, the transmission and absorption can be reduced, and the blazed grating can perform better within a specific wavelength range, thereby improving the performance of the optical system including the blazed grating.

[0071] In summary, the blazed grating manufacturing method provided in the embodiment of the present application can realize the manufacture of blazed gratings with any blazed angle and vertex angle, and there is no need to customize the polarized silicon substrate in the manufacturing process. Compared with the single crystal silicon anisotropic etching method in the related art, which requires the customization of the polarized silicon substrate, the method of manufacturing the blazed grating provided in the present application has lower requirements on the substrate and enriches the manufacturing method of the blazed grating. At the same time, the embodiment of the present application does not use wet etching in the manufacturing process, which is more conducive to forming a sharp vertex angle, can reduce the risk of the top being a plane, and is also helpful to manufacture a blazed grating with a vertex angle of 90 degrees to avoid the incident light being blocked by the adjacent grating, thereby improving the diffraction efficiency of the blazed grating.

[0072] An embodiment of the present application further provides a blazed grating, which is manufactured by the blazed grating manufacturing method in any embodiment of the present application.

[0073] Please refer to Figure 8 , Figure 8 This is a schematic diagram of a block diagram of the composition of a laser provided in an embodiment of the present application. Figure 8 As shown, the laser 2000 includes a semiconductor optical amplifier 2001 and a scanning element 2002 .

[0074] The semiconductor optical amplifier 2001 has a first output terminal OUT1 and a second output terminal OUT2, and the semiconductor optical amplifier 2001 is configured to output laser light via the first output terminal OUT1. The semiconductor optical amplifier (SOA) 2001 is an optical amplifier device based on semiconductor materials, which can be used to amplify optical signals.

[0075] The scanning element 2002 includes a blazed grating 20021 and a driving unit 20022, wherein the blazed grating 20021 is a blazed grating made by the blazed grating manufacturing method in any embodiment of the present application. The blazed grating 20021 is used to receive the laser output from the first output terminal OUT1 and diffract it so that part of the laser is emitted to the first output terminal OUT1. The laser emitted to the first output terminal OUT1 is emitted from the second output terminal OUT2 after being amplified by the semiconductor optical amplifier 2001. The driving unit 20022 is used to drive the blazed grating 20021 to rotate so that the blazed grating 20021 can move according to predetermined requirements, thereby accurately controlling the position and angle of the blazed grating 20021 and realizing wavelength tuning.

[0076] In this embodiment, by using the blazed grating 20021 as a spectroscopic element in the laser 2000, the laser 2000 can have a wider tuning range and higher output power, and the laser 2000 can also be used as a single-mode high-quality light source. Secondly, since the blazed grating 20021 is obtained by the blazed grating manufacturing method in the embodiment of the present application, on the one hand, the cost is reduced by not using a customized polarized silicon substrate, thereby reducing the cost of the laser 2000; on the other hand, the method for manufacturing the blazed grating provided in the present application is relatively simple, thereby reducing the overall design difficulty of the laser 2000; on the other hand, since no wet etching is used, it is more conducive to forming a sharp vertex angle, so the laser 2000 can continue to provide high-quality light.

[0077] In one embodiment, the scanning element 2002 is a MEMS (Micro-Electro-Mechanical System) scanning element. Fig. 9 As shown, the MEMS scanning element includes a blazed grating 20021 , a driving unit 20022 , a fixing portion 20023 and a torsion axis 20024 .

[0078] The fixing part 20023 is provided with a receiving groove. The blazed grating 20021 is arranged in the receiving groove. The torsion shaft 20024 is respectively connected to the blazed grating 20021 and the fixing part 20023, so that the blazed grating 20021 can rotate relative to the fixing part 20023 around the torsion shaft 20024. The driving unit 20022 is used to drive the blazed grating 20024 to rotate.

[0079] In this embodiment, the driving unit 20022 includes a coil 200221 and a magnet 200222 .

[0080] The coil 200221 is disposed on the side of the blazed grating 20021 away from the blazed surface, i.e., the bottom surface of the substrate 100, and the magnet 200222 is disposed outside the blazed grating 20021. The magnet 200222 and the coil 200221 are used to cooperate with each other to drive the blazed grating 20021 to rotate relative to the fixed part 20023. Specifically, the magnet 200222 can provide a magnetic field so that when the coil 200221 is energized, the torsion shaft 20024 is driven to move, so as to drive the blazed grating 20021 to rotate relative to the fixed part 20023.

[0081] This embodiment takes the example of arranging the coil 200221 on the side of the blazing grating 20021 away from the blazing surface and the magnet 200222 outside the blazing grating 20021. In other embodiments, the magnet 200222 may be arranged on the side of the blazing grating 20021 away from the blazing surface and the coil 200221 may be arranged outside the blazing grating 20021, which can also drive the torsion shaft 20024 to move.

[0082] In the related art, the method of driving the blazed grating is usually a PZT (Piezoelectric Ceramic) drive method or a mechanical drive method, wherein the PZT drive method is specifically that the blazed grating is fixed on the PZT element, and the extension or contraction degree of the PZT element can be accurately controlled by changing the voltage applied to the PZT element. The deformation of the PZT will cause the angle of the blazed grating to change, thereby affecting the diffraction pattern of the incident light; the mechanical drive method is specifically to adjust the angle of the grating through a mechanical device (such as a motor). However, for the PZT drive method, the telescopic distance of the PZT element is mostly at the μm level, resulting in a small rotation angle of the blazed grating. In addition, due to the creep phenomenon of the PZT element, the stability of the laser may be adversely affected; for the mechanical drive method, there may be mechanical wear and assembly errors, which will also cause the stability of the laser to be adversely affected.

[0083] The embodiment of the present application integrates the blazed grating 20021 into the MEMS scanning element. On the one hand, the method of driving the blazed grating 20021 can make the blazed grating have a larger rotation angle, so that the blazed grating 20021 can cover a wider wavelength range and have a higher resolution, and can also be suitable for the needs of different application scenarios; on the other hand, there is no mechanical wear, which is beneficial to increase the service life of the laser 2000.

[0084] In summary, by using the blazed grating 20021 as a spectroscopic element in the laser 2000, the laser 2000 can have a wider tuning range and a higher output power, and the laser 2000 can also be used as a single-mode high-quality light source. Secondly, since the blazed grating 20021 is obtained by the blazed grating manufacturing method in the embodiment of the present application, on the one hand, the cost is reduced by not using a customized polarized silicon substrate, thereby reducing the cost of the laser 2000; on the other hand, the method for manufacturing the blazed grating provided in the present application is relatively simple, thereby reducing the overall design difficulty of the laser 2000; on the other hand, since wet etching is not used, it is more conducive to forming a sharp vertex angle, so the laser 2000 can continue to provide high-quality light. In addition, when the scanning element in the laser 2000 is configured as a MEMS scanning element, the method of driving the blazed grating 20021 can make the blazed grating have a larger rotation angle, so that the blazed grating 20021 can cover a wider wavelength range and have a higher resolution. It can also be adapted to the needs of different application scenarios. At the same time, there is no mechanical wear, which can increase the service life of the laser 2000.

[0085] The above descriptions are merely embodiments of the present application and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

[0086] The above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them. Under the idea of ​​the present application, the technical features in the above embodiments or different embodiments can also be combined, and the steps can be implemented in any order. It should be understood by ordinary technicians in this field that they can still modify the technical solutions recorded in the above embodiments, or replace some of the technical features by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for manufacturing a blazed grating, characterized in that: include: Etching the substrate to obtain a plurality of side walls and a plurality of grooves, wherein the side walls extend along a first direction, the side walls are arranged at intervals along a second direction, the second direction is perpendicular to the first direction, there is a groove between any two adjacent side walls, the side walls have a first side surface and a second side surface arranged along the second direction, and the second direction is a direction from the first side surface to the second side surface; Filling the groove with a first photoresist; The third direction of the substrate is configured to be parallel to the direction of the exposure light beam, and the first photoresist is exposed, wherein the third direction is a direction in which the top edge of the second side surface in the same groove points to the bottom edge of the first side surface; developing the first photoresist to obtain a shining surface; Each of the side walls is etched to obtain a plurality of connection surfaces, wherein the bottom edge of the connection surface is the bottom edge of the first side surface, and the top edge of the connection surface is the top edge of the second side surface.

2. The method according to claim 1, characterized in that The etching of the substrate to obtain a plurality of sidewalls and a plurality of grooves comprises: Spin coating a second photoresist on the surface of the substrate; Exposing and developing the second photoresist to obtain a plurality of masks and revealing the area of ​​the substrate outside the masks, wherein the masks extend along the first direction and the masks are arranged at intervals along the second direction; Etching the exposed area of ​​the substrate to obtain the plurality of side walls and the plurality of grooves; The mask is removed.

3. The method according to claim 1, characterized in that Filling the groove with the first photoresist comprises: A first photoresist is spin-coated on the surface of the substrate until the groove is filled with the first photoresist.

4. The method according to claim 1, characterized in that: The etching of each of the side walls to obtain a plurality of connection surfaces comprises: The substrate is configured such that the blazing surface is parallel to the emission direction of the ion beam, and the emission direction of the ion beam is perpendicular to the bottom edge of the first side surface; An ion beam is emitted, and the substrate is controlled to rotate around a preset axis to perform plasma etching on the side wall and form the connecting surface, wherein the preset axis is parallel to the bottom edge of the first side surface.

5. The method according to claim 1, characterized in that The included angle between the blazing surface and the upstream adjacent connecting surface is 90 degrees.

6. The method according to claim 1, characterized in that After etching each of the side walls to obtain a plurality of connection surfaces, the method further comprises: Applying an anti-reflection film to the shining surface and / or the connecting surface; Wherein, the material of the anti-reflection film includes gold or aluminum.

7. A blazed grating, characterized in that: The blazed grating is produced by the method according to any one of claims 1 to 6.

8. A laser, characterized in that: include: A semiconductor optical amplifier having a first output end and a second output end, wherein the semiconductor optical amplifier is configured to output laser light via the first output end; as well as A scanning element, comprising a blazed grating and a driving unit, wherein the blazed grating is used to receive the laser and diffract it, so that part of the laser is emitted to the first output end and emitted from the second output end after being amplified by the semiconductor optical amplifier, and the driving unit is used to drive the blazed grating to rotate; Wherein, the blazed grating is the blazed grating described in claim 7.

9. The laser according to claim 8, characterized in that The scanning element is a MEMS scanning element, and the MEMS scanning element includes: The fixing part is provided with a receiving groove; The blazed grating is arranged in the receiving groove; a torsion shaft, connected to the blazed grating and the fixing portion, respectively, so that the blazed grating can rotate relative to the fixing portion; and The driving unit is used to drive the blazed grating to rotate.

10. The laser according to claim 9, characterized in that The driving unit includes a magnet and a coil; One of the magnet and the coil is arranged on the side of the blazed grating away from the blazed surface, and the other is arranged outside the blazed grating. The magnet and the coil are used to cooperate with each other to drive the blazed grating to rotate relative to the fixed part.

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