Semiconductor structure, self-supporting gallium nitride layer and method for producing same

Abstract

The application relates to a semiconductor structure, a self-supporting gallium nitride layer and a preparation method thereof, and comprises the following steps: providing a substrate; placing the substrate in a hydride vapor phase epitaxy device; introducing a nitrogen-containing gas and a silicon-containing gas into the hydride vapor phase epitaxy device, the nitrogen-containing gas and the silicon-containing gas react to form a patterned mask layer on the substrate, and the patterned mask layer has a plurality of pores; stopping the introduction of the silicon-containing gas into the hydride vapor phase epitaxy device, continuously introducing the nitrogen-containing gas into the hydride vapor phase epitaxy device, and introducing hydrogen chloride gas into the hydride vapor phase epitaxy device to form a gallium nitride layer in the pores and on the surface of the patterned mask layer away from the substrate. By introducing the nitrogen-containing gas and the silicon-containing gas into the hydride vapor phase epitaxy device, the patterned mask layer with a plurality of pores can be formed on the substrate, without the process steps such as photolithography and etching, so that the process flow is greatly simplified, and the production efficiency is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor, in particular to a semiconductor structure, a self-supporting gallium nitride layer and a preparation method thereof. BACKGROUND

[0002] Compared with traditional substrate materials, gallium nitride has superior characteristics such as large band gap, high breakdown voltage, large thermal conductivity, high electron saturation drift speed, strong radiation resistance and good chemical stability. It is the highest material system in theory for electro-optical and photoelectric conversion efficiency. Gallium nitride single crystal substrate is difficult to prepare, and needs to be prepared by a method of heteroepitaxy of gallium nitride material on a sapphire, silicon carbide, silicon, gallium arsenide or other substrate. The gallium nitride single crystal substrate is obtained by peeling it from the substrate.

[0003] At present, the method for peeling off the substrate is to form a patterned mask layer on the substrate to reduce the bonding force between the substrate and the epitaxial gallium nitride, so as to help separation. However, the preparation of this patterned mask layer is very difficult, which needs ten to thirty processes, including uniform angle, film hardening, photoetching, development, degumming, film plating, etching, degumming again, multiple cleaning, etc. The whole process flow is complex, the production efficiency is low, and the production cost is high. At the same time, many devices including deposition equipment, photoetching equipment and etching equipment are used. The substrate is easily contaminated in the process of forming the patterned mask layer, which introduces a pollution source for the subsequent gallium nitride epitaxy, thereby affecting the quality of gallium nitride.

[0004] Therefore, how to prepare a gallium nitride single crystal substrate which is easy to peel off is a problem to be solved at present. SUMMARY

[0005] Therefore, it is necessary to provide a semiconductor structure, a self-supporting gallium nitride layer and a preparation method thereof in view of the problems in the prior art.

[0006] In order to achieve the above object or other objects, according to some embodiments, a preparation method of a semiconductor structure is provided, comprising:

[0007] providing a substrate;

[0008] placing the substrate in a hydride vapor phase epitaxy device; introducing a nitrogen-containing gas and a silicon-containing gas into the hydride vapor phase epitaxy device, the nitrogen-containing gas and the silicon-containing gas react to form a patterned mask layer on the substrate, the patterned mask layer has a plurality of pores therein;

[0009] stopping the feeding of the silicon-containing gas into the hydride vapor phase epitaxy apparatus, continuously feeding the nitrogen-containing gas into the hydride vapor phase epitaxy apparatus, and feeding a hydrogen chloride gas into the hydride vapor phase epitaxy apparatus, the hydrogen chloride gas reacting with gallium in the hydride vapor phase epitaxy apparatus and then reacting with the nitrogen-containing gas to form a gallium nitride layer in the pores and on the surface of the patterned mask layer away from the substrate.

[0010] The semiconductor structure preparation method provided by the above embodiments can form a patterned mask layer with pores on a substrate by feeding a nitrogen-containing gas and a silicon-containing gas into a hydride vapor phase epitaxy apparatus, that is, the same apparatus used for growing a gallium nitride layer can be used to grow the required patterned mask layer by reaction of the reaction gases, without the need for photolithography and etching processes, thereby greatly simplifying the process flow and improving production efficiency; and without the need for using deposition apparatuses, photolithography apparatuses or etching apparatuses and other semiconductor apparatuses, the structural design of the preparation device is simplified, production costs are saved, and the introduction of new pollution is avoided. In addition, the semiconductor structure preparation method provided by the above embodiments includes the step of feeding a nitrogen-containing gas into the hydride vapor phase epitaxy apparatus, and no additional growth apparatus is required when growing the gallium nitride layer, thereby further improving production efficiency and reducing production costs.

[0011] In one of the embodiments, before forming the patterned mask layer on the substrate, the method further comprises:

[0012] forming a first nitride buffer layer on the surface of the substrate; and forming the patterned mask layer on the first nitride buffer layer.

[0013] In one of the embodiments, after forming the first nitride buffer layer on the surface of the substrate, and before forming the patterned mask layer on the substrate, the method further comprises:

[0014] forming a second nitride buffer layer on the surface of the first nitride buffer layer away from the substrate; and forming the patterned mask layer on the surface of the second nitride buffer layer away from the first nitride buffer layer.

[0015] In one of the embodiments, the porosity of the pores in the patterned mask layer is less than 30%.

[0016] In the semiconductor structure preparation method provided by the above embodiments, the porosity of the patterned mask layer formed is less than 30%, that is, the area of the substrate covered by the patterned mask layer is greater than 70%, which can avoid the collapse of the gallium nitride layer formed subsequently due to too many pores in the patterned mask layer, and further facilitate the peeling of the gallium nitride layer formed in the above embodiments.

[0017] In one of the embodiments, the nitrogen-containing gas comprises ammonia, the silicon-containing gas comprises silane, the reaction temperature of the nitrogen-containing gas and the silicon-containing gas is 800-1100 DEG C during the process of forming the patterned mask layer on the substrate, and the reaction time of the nitrogen-containing gas and the silicon-containing gas is 10s-30min; the flow rate of the nitrogen-containing gas is 1sccm-20slm, and the flow rate of the silicon-containing gas is 1sccm-1slm.

[0018] In one of the embodiments, the thickness of the patterned mask layer is 1nm-3um.

[0019] In one of the embodiments, the hydride vapor phase epitaxy device comprises a gallium boat area, a substrate area, a first gas supply pipeline, a second gas supply pipeline and a third gas supply pipeline.

[0020] The gallium boat area and the substrate area are arranged at intervals, and a gallium boat containing gallium is placed in the gallium boat area.

[0021] The substrate is located in the substrate area.

[0022] The first gas supply pipeline extends to the substrate area and is used for introducing the nitrogen-containing gas into the hydride vapor phase epitaxy device.

[0023] The second gas supply pipeline extends to the substrate area and is used for introducing the silicon-containing gas into the hydride vapor phase epitaxy device.

[0024] The third gas supply pipeline extends to the gallium boat area and is used for introducing the hydrogen chloride gas into the hydride vapor phase epitaxy device.

[0025] Based on the same inventive concept, the present application also provides, according to some embodiments, a semiconductor structure prepared by the method for preparing a semiconductor structure according to any one of the preceding embodiments.

[0026] The semiconductor structure provided by the above embodiments is prepared by the method for preparing a semiconductor structure according to any one of the preceding embodiments, and thus can achieve the technical effects of the method for preparing a semiconductor structure, which will not be described in detail here.

[0027] Based on the same inventive concept, the present application also provides, according to some embodiments, a method for preparing a self-supporting gallium nitride layer, comprising:

[0028] The semiconductor structure is prepared by the method for preparing a semiconductor structure according to any one of the preceding embodiments.

[0029] The semiconductor structure is subjected to a cooling process so that the gallium nitride layer is automatically peeled off to obtain a self-supporting gallium nitride layer.

[0030] The preparation method of the self-supporting gallium nitride layer provided in the above embodiment adopts the preparation method of the semiconductor structure provided in any of the above embodiments, and thus can achieve the technical effects of the preparation method of the semiconductor structure, which will not be described here in detail. The gallium nitride layer can be automatically peeled off due to thermal mismatch between the gallium nitride layer and the substrate through the cooling process.

[0031] Based on the same inventive concept, the present application also provides, according to some embodiments, a self-supporting gallium nitride layer, which is prepared by using the preparation method of the self-supporting gallium nitride layer provided in the above embodiments.

[0032] The self-supporting gallium nitride layer provided in the above embodiment is prepared by using the preparation method of the self-supporting gallium nitride layer provided in the above embodiments, and thus can achieve the technical effects of the preparation method of the self-supporting gallium nitride layer, which will not be described here in detail. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0034] Figure 1 Flow chart of the preparation method of the semiconductor structure provided in one of the embodiments of the present application;

[0035] Figure 2 Cross-sectional structure schematic diagram of the structure obtained in step S11 in the preparation method of the semiconductor structure provided in one of the embodiments of the present application;

[0036] Figure 3 Cross-sectional structure schematic diagram of the structure obtained before step S12 in the preparation method of the semiconductor structure provided in one of the embodiments of the present application;

[0037] Figure 4 Cross-sectional structure schematic diagram of the structure obtained in step S12 in the preparation method of the semiconductor structure provided in one of the embodiments of the present application;

[0038] Figure 5 Cross-sectional structure schematic diagram of the structure obtained in step S13 in the preparation method of the semiconductor structure provided in one of the embodiments of the present application;

[0039] Figure 6A flow chart of a method of fabricating a self-supporting gallium nitride layer is provided for one embodiment of the present application.

[0040] BRIEF DESCRIPTION OF DRAWINGS

[0041] 10, substrate; 20, first nitride buffer layer; 30, second nitride buffer layer; 40, patterned mask layer; 401, aperture; 50, gallium nitride layer. DETAILED DESCRIPTION

[0042] For the purposes of this application, the following description will be made with reference to the accompanying drawings in which preferred embodiments of the application are shown. The application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the application to those skilled in the art.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0044] It should be understood that when an element or layer is referred to as being "on" or "connected to" another element or layer, it can be directly on or connected to the other element or layer or intervening elements or layers can be present. In addition, it should be understood that, although the terms first, second, etc. can be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present application. For example, a first reaction gas can be termed a second reaction gas, and similarly, a second reaction gas can be termed a first reaction gas, where the first reaction gas and the second reaction gas are different reaction gases.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The use of the terms "and / or" includes a combination of one or more of the associated listed items.

[0046] When using the terms “including,” “having,” and “comprising” as described herein, another component may be added unless explicitly qualifying terms such as “only,” “consisting of,” etc. are used. Unless otherwise stated, singular terms may include plural forms and should not be construed as having a quantity of one.

[0047] Gallium nitride single crystal substrates are difficult to prepare. They need to be prepared by heteroepitaxial growth of gallium nitride material on substrates such as sapphire, silicon carbide, silicon, and gallium arsenide. Then, the gallium nitride single crystal substrate is obtained by peeling it off the substrate.

[0048] Currently, the method for separating gallium nitride (GaN) single-crystal substrates involves depositing a patterned substrate layer onto the substrate to reduce the bonding force between the substrate and the GaN single-crystal substrate, thus aiding separation. However, the fabrication of this patterned substrate is extremely difficult, requiring ten to thirty steps, such as corner equalization, hardening, photolithography, development, resist removal, coating, resist removal again, and multiple cleaning processes. Existing methods for forming patterned mask layers involve complex and cumbersome processes, requiring numerous semiconductor devices such as deposition, photolithography, and etching equipment. Furthermore, additional growth equipment is needed for GaN growth, resulting in low production efficiency and high production costs. Moreover, the fabrication process easily contaminates the substrate, introducing a contaminant source for subsequent GaN epitaxy.

[0049] Therefore, how to prepare gallium nitride single-crystal substrates that are easy to peel off is an urgent problem to be solved.

[0050] In view of the above-mentioned shortcomings in the prior art, this application provides a method for preparing a semiconductor structure according to some embodiments.

[0051] Please see Figure 1 In one embodiment, the method for fabricating the semiconductor structure may specifically include the following steps:

[0052] S11: Provides a substrate.

[0053] S12: Place the substrate in a hydride vapor phase epitaxy (HVPE) apparatus; introduce nitrogen-containing gas and silicon-containing gas into the hydride vapor phase epitaxy apparatus, and react the nitrogen-containing gas and silicon-containing gas to form a patterned mask layer on the substrate, the patterned mask layer having a number of pores.

[0054] S13: Stop introducing silicon-containing gas into the hydride vapor phase epitaxy equipment, continue to introduce nitrogen-containing gas into the hydride vapor phase epitaxy equipment, and introduce hydrogen chloride gas into the hydride vapor phase epitaxy equipment. The hydrogen chloride gas reacts with gallium in the hydride vapor phase epitaxy equipment and then reacts with nitrogen-containing gas to form a gallium nitride layer in the pores and on the surface of the patterned mask layer away from the substrate.

[0055] The method for manufacturing the semiconductor structure provided by the above embodiment can form the patterned mask layer 40 on the substrate 10 by using the same equipment as that for growing the gallium nitride layer 50, introducing the nitrogen-containing gas and the silicon-containing gas into the hydride vapor phase epitaxy equipment, and growing by reaction of the reaction gas, without the process steps such as photolithography and etching, greatly simplifying the process flow and improving the production efficiency; and without the need to start up the deposition equipment, the photolithography equipment, or the etching equipment and other semiconductor equipment, simplifying the structural design of the manufacturing device, saving production costs, and also avoiding the introduction of new pollution. In addition, since the above manufacturing method includes the step of introducing the nitrogen-containing gas into the hydride vapor phase epitaxy equipment, no additional growth equipment is needed when growing the gallium nitride layer 50, further improving the production efficiency and reducing the production cost. The patterned mask layer 40 on the substrate 10 has a plurality of apertures 401, which not only can release the stress between the lattices of the gallium nitride layer 50 formed in the subsequent process, improving the growth quality of the gallium nitride layer 50, but also help the gallium nitride layer 50 formed in the subsequent process to be peeled off.

[0056] For step S11, please refer to step S11 in Figure 1 and Figure 2 , and the substrate 10 is provided.

[0057] The material of the substrate 10 is not specifically limited in the present application, and the substrate 10 can include one or more of a silicon (Si) substrate, a sapphire substrate, a silicon carbide (SiC) substrate, a gallium arsenide (GaAs) substrate, an aluminum nitride (AlN) substrate, or a gallium nitride (GaN) substrate, etc.

[0058] In one embodiment, as shown in Figure 1 and Figure 3 , a first nitride buffer layer 20 can be formed on the surface of the substrate 10 before step S12. In this embodiment, the patterned mask layer 40 can be formed on the first nitride buffer layer 20.

[0059] The material of the first nitride buffer layer 20 is not specifically limited in the present application, and the first nitride buffer layer 20 can include but is not limited to an aluminum nitride layer.

[0060] Further, in one embodiment, as shown in Figure 1 and Figure 3 , a second nitride buffer layer 30 can be formed on the surface of the first nitride buffer layer 20 away from the substrate 10 after step S12 and before step S14. In this embodiment, the patterned mask layer 40 can be formed on the surface of the second nitride buffer layer 30 away from the first nitride buffer layer 20.

[0061] The material of the second nitride buffer layer 30 is not limited in the present application, and the second nitride buffer layer 30 can include one or more of a gallium nitride layer, an indium gallium nitride (InGaN) layer, a magnesium-doped indium gallium nitride (MgInGaN) layer, or a magnesium-doped gallium nitride (MgGaN) layer, etc.

[0062] The thickness of the second nitride buffer layer 30 is not limited in the present application. In one embodiment, the thickness of the second nitride buffer layer 30 can be 1 μm to 50 μm, for example, the thickness of the second nitride buffer layer 30 can be 1 μm, 15 μm, 25 μm, 35 μm, or 50 μm, etc. It can be understood that the above data is only an example, and the thickness of the second nitride buffer layer 30 can be set according to actual needs in actual embodiments, and is not limited by the above data.

[0063] Specifically, the first nitride buffer layer 20 and the second nitride buffer layer 30 can be formed by any one of metal organic chemical vapor deposition (MOCVD), hydride vapor phase epitaxy (HVPE) process, ammonia thermal method, etc.

[0064] For step S12, please refer to step S12 in Figure 1 , and Figure 4 , the substrate 10 is placed in a hydride vapor phase epitaxy device; nitrogen-containing gas and silicon-containing gas are introduced into the hydride vapor phase epitaxy device, the nitrogen-containing gas and the silicon-containing gas react to form a patterned mask layer 40 on the substrate 10, and the patterned mask layer 40 has a plurality of apertures 401.

[0065] The material of the patterned mask layer 40 is not limited in the present application, and the patterned mask layer 40 can include a silicon-based oxide patterned mask layer. For example, the silicon-based nitride can include but is not limited to silicon nitride (SiN x ).

[0066] In one embodiment, the porosity of the apertures 401 in the patterned mask layer 40 is less than 30%.

[0067] In the method for manufacturing a semiconductor structure provided by the above embodiments, the porosity of the patterned mask layer 40 formed is less than 30%, that is, the area of the substrate 10 covered by the patterned mask layer 40 is greater than 70%, which can avoid the collapse of the gallium nitride layer 50 formed subsequently due to too many apertures 401 in the patterned mask layer 40, and further facilitate the peeling of the gallium nitride layer 50 formed in the above embodiments.

[0068] Optionally, the porosity of the porosities 401 can be 5% to 30%, for example, the porosity of the porosities 401 can be 5%, 15%, 20%, 25% or 30%, and the like. It can be understood that the above data is only as an example, in actual embodiments, the porosity of the porosities 401 can be set according to actual needs, and is not limited by the above data.

[0069] In one of the embodiments, the nitrogen-containing gas can include ammonia (NH3), and the silicon-containing gas can include silane (SiH4). n H 2n+2 On this basis, in the process of forming the patterned mask layer 40 on the substrate 10, the reaction temperature of the nitrogen-containing gas and the silicon-containing gas can be 800°C to 1100°C, and the reaction time of the nitrogen-containing gas and the silicon-containing gas can be 10s to 30min; the flow rate of the nitrogen-containing gas can be 1sccm to 20slm, and the flow rate of the silicon-containing gas can be 1sccm to 1slm.

[0070] The above-mentioned embodiments provide a preparation method of a semiconductor structure, in which the patterned mask layer 40 is formed in a hydride vapor phase epitaxy device, which not only has a simple process, but also is not easy to introduce new pollution.

[0071] Since the silicon-containing gas includes silane, the pipeline for introducing the silicon-containing gas can also be used for the step of silicon doping in subsequent processes, thereby simplifying the design of the hydride vapor phase epitaxy device.

[0072] In one of the embodiments, the product of the reaction of the nitrogen-containing gas and the silicon-containing gas in the hydride vapor phase epitaxy device is deposited on the substrate 10 to form the patterned mask layer 40 having a plurality of porosities 401.

[0073] The present application does not make specific limitation on the flow rate of the nitrogen-containing gas introduced into the hydride vapor phase epitaxy device, and the flow rate of the nitrogen-containing gas introduced into the hydride vapor phase epitaxy device can be set according to actual needs. In one of the embodiments, the flow rate of the nitrogen-containing gas can be 1sccm (standard milliliter per minute) to 20slm (standard liter per minute), for example, the flow rate of the nitrogen-containing gas can be 1sccm, 100sccm, 200sccm, 13slm, 15slm or 20slm, and the like. Preferably, the flow rate of the nitrogen-containing gas can be 100sccm to 15slm; more preferably, the flow rate of the nitrogen-containing gas can be 200sccm to 13slm; more preferably, the flow rate of the nitrogen-containing gas can be 500sccm to 15slm, and the like. It can be understood that the above data is only as an example, in actual embodiments, the flow rate of the nitrogen-containing gas introduced into the hydride vapor phase epitaxy device can be set according to actual needs, and is not limited by the above data.

[0074] The flow rate of the silicon-containing gas into the hydride vapor phase epitaxy apparatus is not particularly limited in the present application, and can be set according to actual needs. In one embodiment, the flow rate of the silicon-containing gas can be 1 sccm to 1 slm, for example, the flow rate of the silicon-containing gas can be 1 sccm, 10 sccm, 20 sccm, 500 sccm, 0.7 slm or 1 slm, etc. Preferably, the flow rate of the silicon-containing gas can be 10 sccm to 0.7 slm; more preferably, the flow rate of the silicon-containing gas can be 20 sccm to 500 sccm. It can be understood that the above data is only an example, and the flow rate of the silicon-containing gas into the hydride vapor phase epitaxy apparatus in actual embodiments can be set according to actual needs, and is not limited by the above data.

[0075] The reaction time of the nitrogen-containing gas and the silicon-containing gas is not particularly limited in the present application, and can be set according to actual needs. In one embodiment, the reaction time of the nitrogen-containing gas and the silicon-containing gas can be 10 s to 30 min, for example, the reaction time of the nitrogen-containing gas and the silicon-containing gas can be 10 s, 30 s, 5 min, 15 min or 30 min, etc. It can be understood that the above data is only an example, and the flow rate of the silicon-containing gas into the hydride vapor phase epitaxy apparatus in actual embodiments can be set according to actual needs, and is not limited by the above data.

[0076] The growth temperature of the patterned mask layer 40 is not particularly limited in the present application, and can be 800°C to 1100°C, for example, the growth temperature of the patterned mask layer 40 can be 800°C, 900°C, 1000°C or 1100°C, etc. It can be understood that the above data is only an example, and the growth temperature of the patterned mask layer 40 in actual embodiments can be set according to actual needs, and is not limited by the above data.

[0077] In addition, the thickness and porosity of the patterned mask layer 40 can also be controlled by controlling the time of introducing the nitrogen-containing gas and / or the amount of silicon nitride generated.

[0078] The thickness of the patterned mask layer 40 is not limited in the present application. In one embodiment, the thickness of the patterned mask layer 40 can be 1 nm to 3 μm, for example, the thickness of the patterned mask layer 40 can be 1 nm, 3 nm, 7 nm, 500 nm, 1 μm, 2 μm or 3 μm, etc. Preferably, the thickness of the patterned mask layer 40 can be 3 nm to 2 μm; more preferably, the thickness of the patterned mask layer 40 can be 5 nm to 1 μm; more preferably, the thickness of the patterned mask layer 40 can be 7 nm to 500 nm. It is to be understood that the above data are only examples, and the thickness of the patterned mask layer 40 can be set according to actual needs in actual embodiments, and is not limited by the above data.

[0079] In one embodiment, the nitrogen-containing gas and the silicon-containing gas can be introduced into the hydride vapor phase epitaxy apparatus in step S12, and a carrier gas can also be introduced into the hydride vapor phase epitaxy apparatus.

[0080] The type of the carrier gas is not limited in the present application. Specifically, the carrier gas can include one or more of hydrogen, nitrogen, helium and argon, etc. It is to be understood that the type of the carrier gas can be set according to actual needs in actual embodiments. More specifically, in one embodiment, the carrier gas includes hydrogen.

[0081] For step S13, please refer to step S13 in Figure 1 , and Figure 5 , stop introducing the silicon-containing gas into the hydride vapor phase epitaxy apparatus, continuously introduce the nitrogen-containing gas into the hydride vapor phase epitaxy apparatus, and introduce hydrogen chloride gas into the hydride vapor phase epitaxy apparatus, the hydrogen chloride gas reacts with gallium in the hydride vapor phase epitaxy apparatus and then reacts with the nitrogen-containing gas, so as to form a gallium nitride layer 50 in the pores 401 and on the surface of the patterned mask layer 40 away from the substrate 10.

[0082] The growth rate of the gallium nitride layer 50 is not limited in the present application. In one embodiment, the gallium nitride layer 50 can be grown at a low speed first, and then grown at a high speed after a certain time; in other embodiments, the gallium nitride layer 50 can also be grown at a constant speed.

[0083] In one embodiment, the hydride vapor phase epitaxy apparatus can include a gallium boat area, a substrate area, a first gas supply pipeline, a second gas supply pipeline and a third gas supply pipeline.

[0084] The gallium boat region can be arranged apart from the substrate region, and the gallium boat region is provided with a gallium boat containing gallium. The substrate 10 can be located in the substrate region. The first gas supply pipeline can extend to the substrate region, and be used for introducing a nitrogen-containing gas into the hydride vapor phase epitaxy equipment. The second gas supply pipeline can extend to the substrate region, and be used for introducing a silicon-containing gas into the hydride vapor phase epitaxy equipment. The third gas supply pipeline can extend to the gallium boat region, and be used for introducing hydrogen chloride gas into the hydride vapor phase epitaxy equipment.

[0085] The preparation method of the semiconductor structure provided by the above embodiment can provide the nitrogen-containing gas to the substrate region through the first gas supply pipeline and introduce the silicon-containing gas into the substrate region through the second gas supply pipeline in the process of forming the patterned mask layer 40. In the process of forming the gallium nitride layer 50, the nitrogen-containing gas is continuously provided to the substrate region through the first gas supply pipeline, and the hydrogen chloride gas is provided to the gallium boat region through the third gas supply pipeline. In this way, the substrate 10 does not need to be taken out by furnace opening operation, and secondary pollution is avoided. In addition, no additional gas or gas pipeline needs to be provided for the process of forming the gallium nitride layer 50, and the device for executing the preparation method is simplified.

[0086] Meanwhile, the hydrogen chloride gas is provided to the gallium boat region through the third gas supply pipeline, which can avoid the reaction of the hydrogen chloride gas with other substances to generate additional loss, thereby saving raw material cost.

[0087] In the preparation method of the semiconductor structure, at the beginning of growth, the silicon-containing gas and the nitrogen-containing gas are provided to react to generate a silicon-based nitride (such as silicon nitride) to form a discontinuous film layer as the patterned mask layer 40, which serves for the self-stripping of the gallium nitride. After the growth of the patterned mask layer 40 is completed, only the silicon-containing gas needs to be stopped, and the nitrogen-containing gas and the gallium chloride (generated by the reaction of hydrogen chloride and gallium) need to be continuously introduced to generate the gallium nitride layer.

[0088] Based on the same inventive concept, the present application also provides a semiconductor structure according to some embodiments.

[0089] Please refer to Figure 5 The semiconductor structure is prepared by the preparation method of the semiconductor structure provided in any of the preceding embodiments, and the technical effects that can be achieved by the preparation method of the semiconductor structure are also achieved by the semiconductor structure, which will not be described here in detail.

[0090] Based on the same inventive concept, the present application also provides a preparation method of a self-supporting gallium nitride layer according to some embodiments.

[0091] Please refer to Figure 6 In one of the embodiments, the preparation method of the self-supporting gallium nitride layer can include the following steps:

[0092] S1: preparing a semiconductor structure by using the preparation method of the semiconductor structure provided in any of the preceding embodiments.

[0093] S2: cooling the semiconductor structure so that the gallium nitride layer 50 is automatically peeled off to obtain a self-supporting gallium nitride layer.

[0094] In the method for preparing the self-supporting gallium nitride layer, the semiconductor structure is prepared by using the method for preparing the semiconductor structure provided in any of the preceding embodiments, and thus the technical effects achieved by the method for preparing the semiconductor structure are also achieved by the method for preparing the self-supporting gallium nitride layer, which will not be described in detail herein. Through the cooling process, the gallium nitride layer 50 can be automatically peeled off due to the thermal mismatch between the gallium nitride layer 50 and the substrate 10.

[0095] According to some embodiments, the application also provides a self-supporting gallium nitride layer prepared by using the method for preparing the self-supporting gallium nitride layer provided in the preceding embodiments, and thus the technical effects achieved by the method for preparing the self-supporting gallium nitride layer are also achieved by the self-supporting gallium nitride layer, which will not be described in detail herein.

[0096] It should be understood that, although Figure 1 the steps in the flowcharts are shown in sequence according to the arrows, the steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, the execution of the steps is not strictly limited in sequence, and the steps can be executed in other sequences. Moreover, Figure 1 at least part of the steps in the flowcharts can include multiple steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of the steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least part of other steps or steps or stages in other steps.

[0097] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features of the above-described embodiments are described, but it should be understood that any combination of the technical features is within the scope of the present disclosure.

[0098] The above-described embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the patent scope of the application. It should be noted that, for those skilled in the art, some modifications and improvements can be made without departing from the concept of the present application, and these are within the protection scope of the present application. Therefore, the patent protection scope of the present application should be subject to the appended claims.

Claims

1. A method for fabricating a semiconductor structure, characterized in that, include: Provide substrate; The substrate is placed in a hydride vapor phase epitaxy apparatus; a nitrogen-containing gas and a silicon-containing gas are introduced into the hydride vapor phase epitaxy apparatus, and the nitrogen-containing gas reacts with the silicon-containing gas to form a patterned mask layer on the substrate, the patterned mask layer having a plurality of pores; After the patterned mask layer is formed, in the same hydride vapor phase epitaxy apparatus, the silicon-containing gas is stopped from being introduced into the hydride vapor phase epitaxy apparatus, while the nitrogen-containing gas is continuously introduced into the hydride vapor phase epitaxy apparatus, and hydrogen chloride gas is introduced into the hydride vapor phase epitaxy apparatus. The hydrogen chloride gas reacts with gallium in the hydride vapor phase epitaxy apparatus and then reacts with the nitrogen-containing gas to form a gallium nitride layer in the pores and on the surface of the patterned mask layer away from the substrate.

2. The method for preparing a semiconductor structure according to claim 1, characterized in that, Before forming the patterned mask layer on the substrate, the method further includes: A first nitride buffer layer is formed on the surface of the substrate; the patterned mask layer is formed on the first nitride buffer layer.

3. The method for preparing a semiconductor structure according to claim 2, characterized in that, After forming the first nitride buffer layer on the surface of the substrate and before forming the patterned mask layer on the substrate, the method further includes: A second nitride buffer layer is formed on the surface of the first nitride buffer layer away from the substrate; the patterned mask layer is formed on the surface of the second nitride buffer layer away from the first nitride buffer layer.

4. The method for preparing a semiconductor structure according to claim 1, characterized in that, In the patterned mask layer, the porosity of the pores is less than 30%.

5. The method for preparing a semiconductor structure according to claim 1, characterized in that, The nitrogen-containing gas includes ammonia, and the silicon-containing gas includes silane. During the formation of the patterned mask layer on the substrate, the reaction temperature between the nitrogen-containing gas and the silicon-containing gas is 800℃~1100℃, and the reaction time between the nitrogen-containing gas and the silicon-containing gas is 10s~30min; the flow rate of the nitrogen-containing gas is 1sccm~20slm, and the flow rate of the silicon-containing gas is 1sccm~1slm.

6. The method for preparing a semiconductor structure according to claim 1, characterized in that, The thickness of the patterned mask layer ranges from 1 nm to 3 μm.

7. The method for preparing a semiconductor structure according to any one of claims 1 to 6, characterized in that, The hydride vapor phase epitaxy equipment includes a gallium boat region, a substrate region, a first gas supply pipeline, a second gas supply pipeline, and a third gas supply pipeline; The gallium boat region and the substrate region are arranged at intervals, and the gallium boat region is where a gallium boat containing gallium is placed; The substrate is located in the substrate region; The first gas supply line extends to the substrate region and is used to introduce the nitrogen-containing gas into the hydride vapor phase epitaxy apparatus; The second gas supply line extends to the substrate region and is used to introduce the silicon-containing gas into the hydride vapor phase epitaxy apparatus; The third gas supply line extends to the gallium boat region and is used to introduce the hydrogen chloride gas into the hydride vapor phase epitaxy device.

8. A semiconductor structure, characterized in that, The semiconductor structure is prepared by the semiconductor structure preparation method as described in any one of claims 1 to 7.

9. A method for fabricating a self-supporting gallium nitride layer, characterized in that, include: The semiconductor structure is prepared using the method for preparing a semiconductor structure as described in any one of claims 1 to 7; The semiconductor structure is cooled to allow the gallium nitride layer to be automatically peeled off, resulting in a self-supporting gallium nitride layer.

10. A self-supporting gallium nitride layer, characterized in that, The self-supporting gallium nitride layer is prepared using the method described in claim 9.

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