Patterned sapphire substrate, method of manufacture and LED epitaxial wafer

Abstract

The application discloses a patterned sapphire substrate, a preparation method and an LED epitaxial wafer. The preparation method of the patterned sapphire substrate comprises the following steps: preparing a photoresist mask on the surface of a sapphire wafer; etching the sapphire wafer by a first plasma source to form a first patterned area, and generating an etching product in the etching process, and simultaneously reacting the etching product with a second plasma source to generate a secondary mask, so that the secondary mask is deposited on the etched surface, wherein the deposition effect of the side surface of the first patterned area is greater than the bottom deposition effect, and the etching effect is greater than the secondary mask deposition effect; and performing pattern modification etching on the first patterned area by the first plasma source to obtain a sapphire-based three-dimensional pattern. By adopting the above scheme, the problems of insufficient transverse etching control ability and excessively long overall etching time of the existing preparation method of the patterned sapphire substrate are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor, in particular to a patterned sapphire substrate, a preparation method and an LED epitaxial wafer. BACKGROUND

[0002] The patterned sapphire substrate is the main substrate material of the LED chip epitaxial wafer, and the patterned sapphire substrate is a substrate material after periodic micro-nano patterning processing on the surface of a sapphire wafer. The mainstream pattern for growing epitaxial materials in the visible spectrum has undergone a series of developments and finally stabilized as a kind of conical side wall micro-arc. The conical side wall is gradually transformed into a conical side wall by a photoresist mask in the patterned etching process, wherein there are two core parameters of the bottom diameter and the height. Due to the high-speed development of the LED industry, the customization of the front-end material caused by the diversification of the downstream end product leads to a plurality of variable combinations between the height and the bottom width of the pattern. Taking the most commonly used 3.0um pattern parameter as an example, the bottom width / height has the following combinations: 2.6um / 1.6um, 2.6 / 1.7um, 2.7um / 1.7um, 2.7 / 1.8um, 2.8um / 1.8um, 2.8 / 1.9um, 2.8 / 2.0um, 2.9um / 1.8um, 2.9 / 1.9um, 2.9um / 2.0um, etc. Higher requirements are put forward for the flexible control of the pattern in terms of width and height. The current etching process generally uses BCl3 as the main etching gas and CHF3 as the auxiliary etching gas due to the single type of etching gas, which makes it difficult to efficiently control the change of the width parameter of the pattern during the etching process, that is, the lateral etching process of the pattern lacks regulation. And due to the strong bond energy of sapphire, the single gas is mainly physical etching, and the chemical etching ability of the auxiliary gas is weak in accelerating the etching process, and the overall etching rate is slow. SUMMARY

[0003] The present application provides a patterned sapphire substrate, a preparation method and an LED epitaxial wafer to solve the problem of unclear lateral etching control ability and too long overall etching time of the existing preparation method of the patterned sapphire substrate.

[0004] According to one aspect of the present application, a preparation method of a patterned sapphire substrate is provided, and the preparation method of the patterned sapphire substrate comprises:

[0005] Preparation of a photoresist mask on the surface of a sapphire wafer;

[0006] etching the sapphire wafer by the first plasma source to form a first patterned region, and generating etching products in the etching process, and simultaneously reacting the etching products by the second plasma source to generate a secondary mask, so that the secondary mask is deposited on the etched surface, wherein the deposition effect on the side of the first patterned region is greater than the deposition effect on the bottom, and the etching effect is greater than the deposition effect of the secondary mask;

[0007] performing pattern modification etching on the first patterned region by the first plasma source to obtain a sapphire-based three-dimensional pattern.

[0008] In an optional embodiment of the present application, after the etching of the sapphire wafer by the first plasma source to form a first patterned region, and generating etching products in the etching process, and simultaneously reacting the etching products by the second plasma source to generate a secondary mask, so that the secondary mask is deposited on the etched surface, wherein the deposition effect on the side of the first patterned region is greater than the deposition effect on the bottom, and the etching effect is greater than the deposition effect of the secondary mask, the method further comprises:

[0009] performing etching on the first patterned region by the first plasma source to form a second patterned region, and generating etching products in the etching process, and simultaneously reacting the etching products by the third plasma source to generate a tertiary mask, so that the tertiary mask is deposited on the etched surface, wherein the deposition effect on the photoresist residual region is greater than the deposition effect on the non-photoresist residual region, and the etching effect is greater than the deposition effect of the tertiary mask;

[0010] Correspondingly, the performing pattern modification etching on the first patterned region by the first plasma source to obtain a sapphire-based three-dimensional pattern comprises:

[0011] performing pattern modification etching on the second patterned region by the first plasma source to obtain a sapphire-based three-dimensional pattern.

[0012] In an optional embodiment of the present application, after the etching of the sapphire wafer by the first plasma source to form a first patterned region, and generating etching products in the etching process, and simultaneously reacting the etching products by the second plasma source to generate a secondary mask, so that the secondary mask is deposited on the etched surface, wherein the deposition effect on the side of the first patterned region is greater than the deposition effect on the bottom, and the etching effect is greater than the deposition effect of the secondary mask, the method further comprises:

[0013] etching the sapphire substrate by the first plasma source to form a first patterned region, generating an etching product in the etching process, and simultaneously reacting the etching product by the third plasma source to generate a third mask, so that the third mask is deposited on the etched surface, wherein the deposition effect of the photoresist residual area is greater than that of the non-photoresist residual area, and the etching effect is greater than the deposition effect of the third mask;

[0014] etching the first patterned region by the first plasma source to form a second patterned region, generating an etching product in the etching process, and simultaneously reacting the etching product by the second plasma source to generate a second mask, so that the second mask is deposited on the etched surface, wherein the deposition effect of the side surface of the second patterned region is greater than that of the bottom, and the etching effect is greater than the deposition effect of the second mask;

[0015] Correspondingly, the first patterned region is patterned and etched by the first plasma source to obtain a sapphire-based three-dimensional pattern, comprising:

[0016] The second patterned region is patterned and etched by the first plasma source to obtain a sapphire-based three-dimensional pattern.

[0017] In an optional embodiment of the present application, at least one of the first plasma source, the second plasma source and the third plasma source is a gas.

[0018] In an optional embodiment of the present application, the preparation method further comprises at least one of the following:

[0019] The first plasma source is at least one of BCl3 and Ar;

[0020] The second plasma source is at least one of N2, NH3 and SF6;

[0021] The third plasma source is at least one of CHF3, SF6 and CF4.

[0022] The generated second mask is at least one of AlN, AlS and SiN;

[0023] The generated third mask is a photoresist fluorocarbon compound.

[0024] In an optional embodiment of the present application, the ratio of the first plasma source and the second plasma source is between 100:1 and 100:99;

[0025] And / or, the ratio of the first plasma source and the third plasma source is between 100:1 and 100:99.

[0026] In an optional embodiment of the present application, the sapphire substrate wafer comprises a sapphire flat sheet and / or a film layer disposed on the sapphire flat sheet, wherein the film layer disposed on the sapphire flat sheet comprises at least one of an inorganic polycrystalline material film layer, a single-crystal material film layer, and an amorphous material film layer.

[0027] In an optional embodiment of the present application, the photoresist mask comprises one of a convex mask and a concave mask.

[0028] And / or, the mask shape of the photoresist mask comprises one of a circle, a regular polygon, and a multi-angle star.

[0029] According to another aspect of the present application, there is provided a patterned sapphire substrate prepared by the method for preparing a patterned sapphire substrate according to any one of the embodiments of the present application.

[0030] According to another aspect of the present application, there is provided an LED epitaxial wafer comprising the patterned sapphire substrate according to any one of the embodiments of the present application.

[0031] The technical solution of the embodiments of the present application, by photoresist mask preparation on the surface of the sapphire substrate wafer, then etching the sapphire substrate wafer by the first plasma source to form a first patterned region, and generating an etching product in the etching process, and at the same time, the second plasma source reacts with the etching product to generate a secondary mask, so that the secondary mask is deposited on the etched surface, wherein the deposition effect of the side of the first patterned region is greater than the bottom deposition effect, and the etching effect is greater than the secondary mask deposition effect, and finally, the first patterned region is patterned and etched by the first plasma source to obtain a sapphire substrate three-dimensional pattern. The secondary mask can be uniformly deposited on the etched surface while the surface material of the sapphire substrate wafer is etched, providing a secondary etching blocking effect, thereby being able to provide a protection effect for the first patterned region, so as to expand the first patterned region, indirectly enhancing the lateral etching capability of the first patterned region in a brand-new way. At the same time, since the lateral etching rate capability is controlled, the pattern control capability can be further improved and the process time can be reduced, greatly improving the production efficiency.

[0032] It should be understood that the content described in this part is not intended to identify key or important features of the embodiments of the present application, nor to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0034] Figure 1 A flow chart of a preparation method of a patterned sapphire substrate provided by the first embodiment of the present application;

[0035] Figure 2 A structural schematic diagram of the patterned sapphire substrate during preparation of the preparation method of the patterned sapphire substrate provided by the first embodiment of the present application;

[0036] Figure 3 A flow chart of a preparation method of a patterned sapphire substrate provided by the second embodiment of the present application;

[0037] Figure 4 A structural schematic diagram of the patterned sapphire substrate during the first etching of the preparation method of the patterned sapphire substrate provided by the second embodiment of the present application;

[0038] Figure 5 A structural schematic diagram of the patterned sapphire substrate during the second etching of the preparation method of the patterned sapphire substrate provided by the second embodiment of the present application;

[0039] Figure 6 A flow chart of a preparation method of a patterned sapphire substrate provided by the third embodiment of the present application;

[0040] Figure 7 A structural schematic diagram of the patterned sapphire substrate during the first etching of the preparation method of the patterned sapphire substrate provided by the third embodiment of the present application;

[0041] Figure 8 A structural schematic diagram of the patterned sapphire substrate during the second etching of the preparation method of the patterned sapphire substrate provided by the third embodiment of the present application.

[0042] Wherein: 1, photoresist mask; 2, sapphire substrate wafer; 3, first patterned region; 4, second mask; 5, second patterned region; 6, third mask. DETAILED DESCRIPTION

[0043] In the following, the technical solutions in the embodiments of the present application will be described clearly and completely with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative effort should fall within the protection scope of the present application.

[0044] It should be noted that the terms "first", "second" and the like in the description and claims of the present application and the above drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily have to include only those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to the process, method, product or device.

[0045] Embodiment one

[0046] Figure 1 A flowchart of a preparation method of a patterned sapphire substrate provided by the embodiment one of the present application, Figure 2 A structural schematic diagram of a patterned sapphire substrate in the preparation of a preparation method of a patterned sapphire substrate provided by the embodiment one of the present application; as Figure 1 And Figure 2 The preparation method of the patterned sapphire substrate includes:

[0047] S110, preparing a photoresist mask 1 on the surface of a sapphire base wafer 2.

[0048] The photoresist mask 1 includes one of a convex mask and a concave mask, and the formed pattern can be convex or concave. Figure 2 The pattern is taken as a convex structure as an example.

[0049] S120, etching the sapphire base wafer 2 by a first plasma source to form a first patterned area 3, and generating an etching product in the etching process, and simultaneously reacting the etching product with a second plasma source to generate a secondary mask 4, so that the secondary mask 4 is deposited on the etched surface, wherein the deposition effect of the side of the first patterned area 3 is greater than the bottom deposition effect, and the etching effect is greater than the deposition effect of the secondary mask 4.

[0050] Wherein, when the photoresist mask 1 is a convex mask, the first patterning area 3 is a convex structure; when the photoresist mask 1 is a concave mask, the first patterning area 3 is a concave structure.

[0051] The first plasma source is a plasma source capable of etching the sapphire substrate 2, and the second plasma source is a plasma source capable of reacting with the etching product formed by the first plasma source to deposit on the etched surface of the sapphire substrate 2. The first plasma source and the second plasma source are respectively used for traditional etching and generating a specific secondary mask 4, and the main functions of the two are obviously different.

[0052] The secondary mask 4 is a product generated by the second plasma source and the etching product in the etching process. The secondary mask 4 is solid and not easy to volatilize, and can be uniformly deposited on the surface of the sapphire substrate 2 and the photoresist to form a film in the etching process, while being etched by the first plasma source. The generation of the secondary mask 4 is optimized for the composition of the etched surface. The etched surface may change due to the etching process, and the second plasma source for generating the secondary mask 4 may also change, so the first plasma source and the second plasma source are not specifically limited here.

[0053] When the first plasma source etches the sapphire substrate 2, the sapphire substrate 2 will be gradually etched to form the first patterning area 3. In this process, the second plasma source will react with the etching product to generate the secondary mask 4 and uniformly deposit on the etched surface to provide a secondary etching blocking effect. Since the etching effect is greater than the deposition effect of the secondary mask 4, the preset pattern can be etched. Since the deposition effect of the secondary mask 4 on the side of the first patterning area 3 is greater than the bottom deposition effect, that is, the thickness of the secondary mask 4 in the vertical direction of the first patterning area 3 is greater than the thickness of the bottom in the vertical direction, so the secondary mask 4 can also provide a protection effect for the first patterning area 3, thereby expanding the first patterning area 3.

[0054] S130, performing pattern modification etching on the first patterning area 3 by the first plasma source to obtain a sapphire-based three-dimensional pattern.

[0055] Wherein, according to different use requirements, the specific shape of the desired sapphire-based three-dimensional pattern is different, and the first plasma source is used to perform pattern modification etching on the first patterning area 3, which can be etched specifically, so that the sapphire substrate 2 can form an ideal sapphire-based three-dimensional pattern.

[0056] The above scheme is realized by the following steps: a photoresist mask 1 is prepared on the surface of the sapphire substrate 2, then the sapphire substrate 2 is etched by a first plasma source to form a first patterned region 3, and an etching product is generated during the etching process, and at the same time, the etching product reacts with a second plasma source to generate a secondary mask 4, so that the secondary mask 4 is deposited on the etched surface, wherein the deposition effect of the side of the first patterned region 3 is greater than the bottom deposition effect, the etching effect is greater than the deposition effect of the secondary mask 4, and finally the first patterned region 3 is etched by the first plasma source to obtain a sapphire substrate three-dimensional pattern. The secondary mask 4 can be uniformly deposited on the etched surface while the material on the surface of the sapphire substrate 2 is etched, providing a secondary etching blocking effect, thereby providing a protection effect for the first patterned region 3, so that the first patterned region 3 is expanded, and the lateral etching capability of the first patterned region 3 is indirectly enhanced in a new way. At the same time, since the lateral etching rate is controlled, the pattern control capability can be further improved and the process time can be reduced, and the production efficiency can be greatly improved.

[0057] In an optional embodiment of the present application, at least one of the first plasma source and the second plasma source is a gas.

[0058] At least one of the first plasma source and the second plasma source is a gas, which can conveniently generate a secondary mask 4 or a tertiary mask 6 on the etched surface while etching.

[0059] On the basis of the above embodiment, the first plasma source is at least one of BCl3 and Ar; wherein BCl3, Ar and other gases can mainly use physical bombardment etching, which can effectively etch the surface of the sapphire substrate 2.

[0060] On the basis of the above embodiment, the second plasma source is at least one of N2, NH3 and SF6. Among them, N2, NH3, SF6 and other gases are easy to react with the etching product generated on the etched surface to form a secondary mask 4 which is not easy to volatilize.

[0061] In an optional embodiment of the present application, the generated secondary mask 4 is at least one of AlN, AlS and SiN, which is not easy to volatilize and can be deposited on the surface of the sapphire substrate 2 and the first patterned region 3 or the second patterned region 5. The secondary mask 4 has different hardness, stability and generation amount, and has different influence on lateral etching under different conditions, and can be used to modulate the lateral etching capability during etching. In actual production, the generation of the secondary mask 4 can be controlled according to the actual situation in production, which is not limited here.

[0062] In an optional embodiment of the present application, the ratio of the first plasma source and the second plasma source is between 100:1 and 100:99; in this way, the etching effect is greater than the deposition effect of the secondary mask 4.

[0063] In an optional embodiment of the present application, the sapphire substrate wafer 2 comprises a sapphire flat sheet and / or a film layer disposed on the sapphire flat sheet, wherein the film layer disposed on the sapphire flat sheet comprises at least one of an inorganic polycrystalline material film layer, a single crystal material film layer, and an amorphous material film layer. Depending on the type of patterned sapphire substrate, etching can be performed on the sapphire flat sheet or on the film layer disposed on the sapphire flat sheet. By including a sapphire flat sheet and / or a film layer disposed on the sapphire flat sheet, the lateral etching capability of the patterned region can be enhanced for different types of patterned sapphire substrates, thereby expanding the first patterned region 3.

[0064] In an optional embodiment of the present application, the mask shape of the photoresist mask 1 comprises one of a circle, a regular polygon, and a multi-angle star. Depending on the type of patterned sapphire substrate, the mask shape of the photoresist also needs to be different. By including one of a circle, a regular polygon, and a multi-angle star, the mask shape can be matched to the requirements of different patterned sapphire substrates, thereby improving versatility.

[0065] Embodiment Two

[0066] Figure 3 A flowchart of a method for preparing a patterned sapphire substrate according to Embodiment Two of the present application is shown in Figure 4 A structural schematic diagram of a patterned sapphire substrate during the first etching of a method for preparing a patterned sapphire substrate according to Embodiment Two of the present application is shown in Figure 5 A structural schematic diagram of a patterned sapphire substrate during the second etching of a method for preparing a patterned sapphire substrate according to Embodiment Two of the present application is shown in Embodiment Two of the present application is improved based on Embodiment One, as shown in Figures 3-5 The method for preparing a patterned sapphire substrate comprises:

[0067] S210, preparing a photoresist mask 1 on the surface of a sapphire substrate wafer 2.

[0068] S220, etching the sapphire substrate wafer 2 by a first plasma source to form a first patterned region 3, and generating an etching product during etching, and simultaneously reacting the etching product with a second plasma source to generate a secondary mask 4, so that the secondary mask 4 is deposited on the etched surface, wherein the deposition effect of the side of the first patterned region 3 is greater than the deposition effect of the bottom, and the etching effect is greater than the deposition effect of the secondary mask 4.

[0069] S230, etching the first patterning region 3 by the first plasma source to form a second patterning region 5, and generating an etching product in the etching process, and simultaneously reacting the etching product with the third plasma source to generate a third mask 6, so that the third mask 6 is deposited on the etched surface, wherein the deposition effect of the photoresist residual area is greater than that of the non-photoresist residual area, and the etching effect is greater than the deposition effect of the third mask 6.

[0070] Wherein, the third mask 6 is the product generated by the third plasma source and the etching product in the etching process, and the third mask 6 is solid and not easy to volatilize, and can be uniformly deposited on the sapphire wafer 2 and the photoresist surface to form a film in the etching process, while being etched by the first plasma source. The third mask 6 is generated by optimizing the composition of the etching product of the etched surface, which has better affinity with the photoresist, so that the deposition effect of the photoresist residual area is greater than that of the non-photoresist residual area, that is, the area where the photoresist exists, the thickness of the third mask 6 is larger than the area where the photoresist does not exist. The etched surface may change due to the etching process, and the third plasma source for generating the third mask 6 adapted to the etched surface may also change, so the third plasma source is not specifically limited here.

[0071] When the first plasma source etches the sapphire wafer 2, the sapphire wafer 2 will be gradually etched to form a first patterning region 3. Then etching the first patterning region 3 with the first plasma source again can obtain a second patterning region 5. In this process, the third plasma source reacts with the etching product to generate a third mask 6 uniformly deposited on the etched surface, providing a third etching blocking effect, and since the etching effect is greater than the deposition effect of the third mask 6, the second patterning region 5 can be etched. Since the deposition effect of the third mask 6 in the photoresist residual area is greater than that in the non-photoresist residual area, the third mask 6 can also provide a protection effect for the second patterning region 5 and control the longitudinal etching of the second patterning region 5.

[0072] S240, performing pattern modification etching on the second patterning region 5 by the first plasma source to obtain a sapphire-based three-dimensional pattern.

[0073] Wherein, according to different use requirements, the specific shape of the desired sapphire-based three-dimensional pattern is different, and by performing pattern modification etching on the second patterning region 5 by the first plasma source, the sapphire wafer 2 can form an ideal sapphire-based three-dimensional pattern.

[0074] The above scheme is realized by the following steps: a photoresist mask 1 is prepared on the surface of the sapphire substrate 2, then the sapphire substrate 2 is etched by a first plasma source to form a first patterned region 3, and an etching product is generated during the etching process, and at the same time, a second mask 4 is generated by reacting the etching product with a second plasma source, so that the second mask 4 is deposited on the etched surface, wherein the deposition effect of the side of the first patterned region 3 is greater than the bottom deposition effect, and the etching effect is greater than the deposition effect of the second mask 4, then the first patterned region 3 is etched by the first plasma source to form a second patterned region 5, and an etching product is generated during the etching process, and at the same time, a third mask 6 is generated by reacting the etching product with a third plasma source, so that the third mask 6 is deposited on the etched surface, wherein the deposition effect of the photoresist residual area is greater than the deposition effect of the non-photoresist residual area, and the etching effect is greater than the deposition effect of the third mask 6. Finally, the second patterned region 5 is etched by the first plasma source to obtain a sapphire substrate three-dimensional pattern. The second mask 4 can be uniformly deposited on the etched surface while the material on the surface of the sapphire substrate 2 is etched, providing a secondary etching blocking effect, thereby providing a protection effect for the first patterned region 3, so that the first patterned region 3 is expanded, and the lateral etching capability of the first patterned region 3 is indirectly enhanced in a new way. The third mask 6 can be uniformly deposited on the etched surface while the first patterned region 3 is etched, providing a third etching blocking effect, thereby providing a protection effect for the second patterned region 5 generated by etching. Since the deposition effect of the third mask 6 in the photoresist residual area is greater than that in the non-photoresist residual area, the third mask 6 can also provide a protection effect for the second patterned region 5, thereby indirectly enhancing the longitudinal etching capability of the second patterned region 5 in a new way. At the same time, since the etching rate capability of the lateral and longitudinal directions is controlled, the pattern control capability can be further improved and the process time can be reduced, thereby greatly improving the production efficiency.

[0075] In optional embodiments of the present application, at least one of the first plasma source, the second plasma source and the third plasma source is a gas.

[0076] In optional embodiments of the present application, at least one of the first plasma source, the second plasma source and the third plasma source is a gas.

[0077] In the above embodiments, the first plasma source is at least one of BCl3 and Ar, wherein BCl3 and Ar can mainly use physical bombardment etching to effectively etch the surface of the sapphire substrate 2.

[0078] On the basis of the above-mentioned embodiments, the second plasma source is at least one of N2, NH3, SF6. Wherein, N2, NH3, SF6 and the like gas, easy to be etched surface of the etching product reaction to form a non-volatile secondary mask 4.

[0079] On the basis of the above-mentioned embodiments, the third plasma source is at least one of CHF3, SF6, CF4. Wherein, CHF3, SF6, CF4 and the like gas, easy to be etched surface of the etching product reaction to form a non-volatile tertiary mask 6.

[0080] In an optional embodiment of the present application, the generated secondary mask 4 is at least one of AlN, AlS, SiN and the like non-volatile, which can be deposited on the surface of the sapphire wafer 2 and the first patterned area 3 or the second patterned area 5. The secondary mask 4 has different hardness, different stability, different generation amount, and different influence degree on lateral etching under different conditions, which can be used to modulate the lateral etching ability in the etching process. In actual production, the generation of the secondary mask 4 can be controlled according to the actual situation in production, which is not limited here.

[0081] In an optional embodiment of the present application, the generated tertiary mask 6 is a photoresist fluorocarbon compound. Wherein, the photoresist fluorocarbon compound has better affinity with photoresist, and the deposition effect in the photoresist residual area is greater than that in the non-photoresist residual area.

[0082] In an optional embodiment of the present application, the ratio of the first plasma source and the second plasma source is between 100:1-100:99. Wherein, in this way, the etching effect can be greater than the deposition effect of the secondary mask 4.

[0083] In an optional embodiment of the present application, the ratio of the first plasma source and the third plasma source is between 100:1-100:99. Wherein, in this way, the etching effect can be greater than the deposition effect of the secondary mask 4.

[0084] In an optional embodiment of the present application, the sapphire-based wafer 2 comprises a sapphire flat sheet and / or a film layer disposed on the sapphire flat sheet, wherein the film layer disposed on the sapphire flat sheet comprises at least one of an inorganic polycrystalline material film layer, a single crystal material film layer, and an amorphous material film layer. According to different types of patterned sapphire substrates, etching can be performed on the sapphire flat sheet or on the film layer disposed on the sapphire flat sheet. By including the sapphire flat sheet and / or the film layer disposed on the sapphire flat sheet in the sapphire-based wafer 2, the etching capability of the patterned region in the lateral and longitudinal directions can be enhanced for different types of patterned sapphire substrates, so that the first patterned region 3 and the second patterned region 5 are expanded.

[0085] In an optional embodiment of the present application, the mask shape of the photoresist mask 1 comprises one of a circle, a regular polygon, and a multi-angle star. According to different types of patterned sapphire substrates, the mask shape of the photoresist also needs to be different. By including one of a circle, a regular polygon, and a multi-angle star in the mask shape, the requirements of different patterned sapphire substrates for the mask shape can be met, and the versatility is strong.

[0086] Embodiment Three

[0087] Figure 6 A flowchart of a method for preparing a patterned sapphire substrate according to Embodiment Three of the present application is shown in Figure 7 A structural schematic diagram of a patterned sapphire substrate during the first etching of a method for preparing a patterned sapphire substrate according to Embodiment Three of the present application is shown in Figure 8 A structural schematic diagram of a patterned sapphire substrate during the second etching of a method for preparing a patterned sapphire substrate according to Embodiment Three of the present application is shown in Figures 6-8 The method for preparing a patterned sapphire substrate according to Embodiment Three of the present application comprises:

[0088] S310, preparing a photoresist mask 1 on the surface of the sapphire-based wafer 2.

[0089] S320, etching the sapphire-based wafer 2 by a first plasma source to form a first patterned region 3, and generating an etching product during the etching process, and simultaneously reacting the etching product with a third plasma source to generate a third mask 6, so that the third mask 6 is deposited on the etched surface, wherein the deposition effect of the photoresist residual area is greater than that of the non-photoresist residual area, and the etching effect is greater than the deposition effect of the third mask 6.

[0090] In the process, the third plasma source reacts with the etching product to generate the third mask 6 which is uniformly deposited on the etched surface to provide a third etching blocking effect. Since the etching effect is greater than the deposition effect of the third mask 6, the second patterning area 5 can be etched. Since the deposition effect of the third mask 6 on the photoresist residual area is greater than that on the non-photoresist residual area, the third mask 6 can also provide a protection effect on the first patterning area 3 to control the longitudinal etching of the first patterning area 3.

[0091] S330, etching the first patterning area 3 by the first plasma source to form the second patterning area 5, and generating an etching product in the etching process, and at the same time, the second plasma source reacts with the etching product to generate the second mask 4, so that the second mask 4 is deposited on the etched surface, wherein the deposition effect of the side of the second patterning area 5 is greater than that of the bottom, and the etching effect is greater than the deposition effect of the second mask 4.

[0092] In the process, the second plasma source reacts with the etching product to generate the second mask 4 which is uniformly deposited on the etched surface to provide a second etching blocking effect. Since the etching effect is greater than the deposition effect of the second mask 4, the preset pattern can be etched. Since the deposition effect of the second mask 4 on the side of the first patterning area 3 is greater than that on the bottom, that is, the thickness of the second mask 4 in the vertical direction of the second patterning area 5 is greater than that of the bottom in the vertical direction, the second mask 4 can also provide a protection effect on the second patterning area 5, so that the second patterning area 5 is expanded.

[0093] S340, performing pattern modification etching on the second patterning area 5 by the first plasma source to obtain a sapphire-based three-dimensional pattern.

[0094] In the process, the third plasma source reacts with the etching product to generate the third mask 6 which is uniformly deposited on the etched surface to provide a third etching blocking effect. Since the etching effect is greater than the deposition effect of the third mask 6, the second patterning area 5 can be etched. Since the deposition effect of the third mask 6 on the photoresist residual area is greater than that on the non-photoresist residual area, the third mask 6 can also provide a protection effect on the first patterning area 3 to control the longitudinal etching of the first patterning area 3.

[0095] The above scheme is realized by the following steps: firstly, a photoresist mask 1 is prepared on the surface of the sapphire substrate 2; then, the sapphire substrate 2 is etched by a first plasma source to form a first patterned region 3, and an etching product is generated during the etching process, and at the same time, a third mask 6 is generated by reacting the etching product with a third plasma source, so that the third mask 6 is deposited on the etched surface, wherein the deposition effect of the photoresist residual area is greater than that of the non-photoresist residual area, and the etching effect is greater than the deposition effect of the third mask 6; then, the first patterned region 3 is etched by the first plasma source to form a second patterned region 5, and an etching product is generated during the etching process, and at the same time, a second mask 4 is generated by reacting the etching product with a second plasma source, so that the second mask 4 is deposited on the etched surface, wherein the deposition effect of the side surface of the second patterned region 5 is greater than that of the bottom, and the etching effect is greater than the deposition effect of the second mask 4; finally, the second patterned region 5 is etched by the first plasma source to obtain a sapphire substrate three-dimensional pattern. The third mask 6 can be uniformly deposited on the etched surface while the sapphire substrate 2 is etched, providing a three-time etching blocking effect, thereby being able to protect the first patterned region 3 generated by etching. Since the deposition effect of the third mask 6 on the photoresist residual area is greater than that on the non-photoresist residual area, the third mask 6 can also protect the first patterned region 3, thereby indirectly enhancing the longitudinal etching capability of the first patterned region 3 in a new way. The second mask 4 can be uniformly deposited on the etched surface while the first patterned region 3 is etched, providing a two-time etching blocking effect, thereby being able to protect the second patterned region 5, so that the second patterned region 5 is expanded, thereby indirectly enhancing the lateral etching capability of the second patterned region 5 in a new way. Since the etching rate capability of the lateral and longitudinal directions is controlled, the pattern control capability can be further improved and the process time can be reduced, thereby greatly improving the production efficiency.

[0096] In optional embodiments of the present application, at least one of the first plasma source, the second plasma source and the third plasma source is a gas.

[0097] In optional embodiments of the present application, at least one of the first plasma source, the second plasma source and the third plasma source is a gas.

[0098] In the above embodiments, the first plasma source is at least one of BCl3 and Ar; wherein BCl3 and Ar and other gases can mainly use physical bombardment etching, which can effectively etch the surface of the sapphire substrate 2.

[0099] On the basis of the above-mentioned embodiments, the second plasma source is at least one of N2, NH3, SF6. Wherein, N2, NH3, SF6 and the like gas, easy to be etched surface of the etching product reaction to form a non-volatile secondary mask 4.

[0100] On the basis of the above-mentioned embodiments, the third plasma source is at least one of CHF3, SF6, CF4. Wherein, CHF3, SF6, CF4 and the like gas, easy to be etched surface of the etching product reaction to form a non-volatile tertiary mask 6.

[0101] In an optional embodiment of the present application, the generated secondary mask 4 is at least one of AlN, AlS, SiN and the like non-volatile, which can be deposited on the surface of the sapphire wafer 2 and the first patterned area 3 or the second patterned area 5. The secondary mask 4 has different hardness, different stability, different generation amount, and different influence degree on lateral etching under different conditions, which can be used to modulate the lateral etching ability in the etching process. In actual production, the generation of the secondary mask 4 can be controlled according to the actual situation in production, which is not limited here.

[0102] In an optional embodiment of the present application, the generated tertiary mask 6 is a photoresist fluorocarbon compound. Wherein, the photoresist fluorocarbon compound has better affinity with photoresist, and the deposition effect in the photoresist residual area is greater than that in the non-photoresist residual area.

[0103] In an optional embodiment of the present application, the ratio of the first plasma source and the second plasma source is between 100:1-100:99. Wherein, in this way, the etching effect can be greater than the deposition effect of the secondary mask 4.

[0104] In an optional embodiment of the present application, the ratio of the first plasma source and the third plasma source is between 100:1-100:99. Wherein, in this way, the etching effect can be greater than the deposition effect of the secondary mask 4.

[0105] In an optional embodiment of the present application, the sapphire-based wafer 2 comprises a sapphire flat sheet and / or a film layer disposed on the sapphire flat sheet, wherein the film layer disposed on the sapphire flat sheet comprises at least one of an inorganic polycrystalline material film layer, a single crystal material film layer and an amorphous material film layer. According to different types of patterned sapphire substrates, etching can be performed on the sapphire flat sheet or on the film layer disposed on the sapphire flat sheet. By comprising the sapphire flat sheet and / or the film layer disposed on the sapphire flat sheet, the etching capability of the patterned region in the lateral and longitudinal directions can be enhanced for different types of patterned sapphire substrates, so that the first patterned region 3 and the second patterned region 5 are expanded.

[0106] In an optional embodiment of the present application, the mask shape of the photoresist mask 1 comprises one of a circle, a regular polygon and a multi-angle star. According to different types of patterned sapphire substrates, the mask shape of the photoresist also needs to be different. By comprising one of a circle, a regular polygon and a multi-angle star, the mask shape can be matched with the requirements of different patterned sapphire substrates, and the versatility is strong.

[0107] Embodiment Four

[0108] Embodiment Four of the present application provides a patterned sapphire substrate prepared by the method for preparing a patterned sapphire substrate according to any one of the embodiments of the present application.

[0109] Since the method for preparing a patterned sapphire substrate can produce a protection effect on the first patterned region and / or the second patterned region, the first patterned region and / or the second patterned region are expanded, and the etching capability of the first patterned region and / or the second patterned region in the lateral and / or longitudinal directions is indirectly enhanced in a new way. At the same time, since the etching capability in the lateral and / or longitudinal directions is controlled, the pattern control capability can be further improved, so that the pattern control capability of the patterned sapphire substrate produced is good.

[0110] Embodiment Five

[0111] Embodiment Five of the present application provides an LED epitaxial wafer comprising the patterned sapphire substrate according to any one of the embodiments of the present application.

[0112] It should be understood that the various forms of flow shown above can be reordered, added or deleted steps. For example, the steps described in the present application can be executed in parallel, in sequence or in different order, as long as the desired results of the technical solutions of the present application can be achieved, which is not limited herein.

[0113] The above detailed description does not limit the scope of the application. Various modifications, combinations, sub-combinations and alternatives can be made to the detailed description. Any modification, equivalent replacement and improvement etc. made within the spirit and principle of the application shall be included in the scope of the application.

Claims

1. A method for preparing a patterned sapphire substrate, characterized in that, include: Photoresist mask preparation on sapphire-based wafer surface; The sapphire-based wafer is etched using a first plasma source to form a first patterned region, generating etching products during the etching process. Simultaneously, a second plasma source reacts with the etching products to generate a secondary mask, which is then deposited on the etched surface. The deposition effect on the sides of the first patterned region is greater than the bottom deposition effect, and the etching effect is greater than the secondary mask deposition effect, thereby enhancing the lateral etching capability of the first patterned region. The first patterned region is then etched using the first plasma source to form a second patterned region, generating etching products during the etching process. Simultaneously, a third plasma source reacts with the etching products to generate a tertiary mask, which is then deposited on the etched surface. The deposition effect in areas with residual photoresist is greater than in areas without residual photoresist, and the etching effect is greater than the tertiary mask deposition effect, thereby enhancing the vertical etching capability of the second patterned region. Finally, the second patterned region is pattern-modified using the first plasma source to obtain a sapphire-based three-dimensional pattern. Alternatively, the sapphire-based wafer can be etched using the first plasma source to form the first patterned region, generating etching products during the etching process, and simultaneously reacting the etching products with a third plasma source to generate the tertiary mask, so that the tertiary mask is deposited on the etched surface. The deposition effect in the photoresist residue area is greater than that in the non-photoresist residue area, and the etching effect is greater than the tertiary mask deposition effect. The first patterned region can be etched using the first plasma source to form the second patterned region, generating etching products during the etching process, and simultaneously reacting the etching products with a second plasma source to generate the secondary mask, so that the secondary mask is deposited on the etched surface. The deposition effect on the sides of the second patterned region is greater than that on the bottom, and the etching effect is greater than the secondary mask deposition effect. The second patterned region can be pattern-modified using the first plasma source to obtain a sapphire-based three-dimensional pattern.

2. The method for preparing a patterned sapphire substrate according to claim 1, characterized in that, At least one of the first plasma source, the second plasma source, and the third plasma source is a gas.

3. The method for preparing a patterned sapphire substrate according to claim 2, characterized in that, The preparation method further includes at least one of the following: The first plasma source is at least one of BCl3 and Ar; The second plasma source is at least one of N2, NH3, and SF6; The third plasma source is at least one of CHF3, SF6, and CF4; The generated secondary mask is at least one of AlN, AlS, and SiN; The resulting triple mask is a photoresist fluorocarbon compound.

4. The method for preparing a patterned sapphire substrate according to claim 1, characterized in that, The ratio of the first plasma source to the second plasma source is between 100:1 and 100:99; And / or, the ratio of the first plasma source to the third plasma source is between 100:1 and 100:

99.

5. The method for preparing a patterned sapphire substrate according to claim 1, characterized in that, The sapphire substrate wafer includes a sapphire flat sheet and / or a film layer disposed on the sapphire flat sheet, wherein the film layer disposed on the sapphire flat sheet includes at least one of a polycrystalline material film layer, a monocrystalline material film layer, and an amorphous material film layer.

6. The method for preparing a patterned sapphire substrate according to claim 1, characterized in that, The photoresist mask includes one type of raised mask and a recessed mask; And / or; the photoresist mask shape includes one of the following: circular, regular polygonal, and polygonal star.

7. A patterned sapphire substrate, characterized in that, It is prepared using the method for preparing a patterned sapphire substrate as described in any one of claims 1-6.

8. An LED epitaxial wafer, characterized in that, Includes the patterned sapphire substrate as described in claim 7.

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