Formation method of semiconductor substrate structure and semiconductor substrate structure

Abstract

The invention relates to a forming method of a semiconductor substrate structure and the semiconductor substrate structure. The method comprises the following steps: providing an initial substrate structure; the initial substrate structure comprises a substrate layer; forming an optical isolation layer on the upper surface of the initial substrate structure by adopting a vapor deposition process; the optical refractive index of the optical isolation layer is less than 1.8, and the dielectric constant of the optical isolation layer is less than 6; the temperature of the vapor deposition process is lower than 200 DEG C; and forming a photoelectric function layer on the upper surface of the optical isolation layer, and performing post-processing on the initial substrate structure to obtain the semiconductor substrate structure. According to the embodiment of the invention, the vapor deposition process is adopted to form the ultra-thick optical isolation layer with the low dielectric constant on the initial substrate structure to improve the propagation speed of microwaves, and the speed matching of microwaves and light waves is realized. According to the method, the semiconductor substrate structure can be rapidly prepared, and the electro-optical modulator prepared by using the semiconductor substrate structure can have both high bandwidth and low half-wave voltage.

Description

Technical Field

[0001] The present invention belongs to the technical field of optoelectronic devices, and in particular relates to a method for forming a semiconductor substrate structure and a semiconductor substrate structure. Background Art

[0002] Electro-optic modulators can efficiently convert electrical signals into optical signals and load information onto optical signals through the modulation process. This function makes electro-optic modulators an indispensable core component in optoelectronic chips and communication systems. The performance of electro-optic modulators directly affects the overall rate and transmission quality of the communication system. Suitable electro-optic modulators can provide stable and reliable signal transmission for high-speed, long-distance communication systems.

[0003] Half-wave voltage and bandwidth are two important parameters that characterize the performance of electro-optic modulators. Electro-optic modulators with smaller half-wave voltage can achieve larger phase modulation at lower voltage, thus having higher modulation efficiency and lower energy consumption. Electro-optic modulators with wider bandwidth can support high-speed signal transmission, thus meeting the needs of modern communication systems for high-speed and large-capacity transmission. At the same time, wider bandwidth also means that electro-optic modulators can process more types of signals, which helps to improve the flexibility and adaptability of communication systems. Therefore, in order to improve the rate and quality of communication systems, it is necessary to reduce the half-wave voltage of the electro-optic modulator and widen its bandwidth.

[0004] In order to ensure that the electro-optic modulator has a smaller half-wave voltage, the electrode spacing usually needs to be set smaller, but this will lead to greater microwave loss, thus limiting the improvement of bandwidth. In response to this, the prior art introduces the design of T-type electrodes, but the T-type electrode will introduce a slow wave effect and cause the speed of microwaves and light waves to not match, resulting in a decrease in bandwidth. Therefore, a solution is needed to reduce the half-wave voltage of the electro-optic modulator and broaden its bandwidth. Summary of the invention

[0005] In order to solve the above technical problems, the present application provides a method for forming a semiconductor substrate structure and a semiconductor substrate structure.

[0006] In a first aspect, an embodiment of the present application discloses a method for forming a semiconductor substrate structure, comprising:

[0007] Providing an initial substrate structure; the initial substrate structure includes a substrate layer;

[0008] An optical isolation layer is formed on the upper surface of the initial substrate structure by a vapor deposition process; the optical refractive index of the optical isolation layer is less than 1.8, and the dielectric constant of the optical isolation layer is less than 6; the temperature of the vapor deposition process is less than 200 degrees Celsius;

[0009] A photoelectric functional layer is formed on the upper surface of the optical isolation layer, and the initial substrate structure is post-processed to obtain a semiconductor substrate structure.

[0010] In some possible embodiments,

[0011] Providing an initial substrate structure, including:

[0012] providing a substrate layer;

[0013] A first stress compensation layer is formed on the lower surface of the substrate layer by a deposition method, and a second stress compensation layer is formed on the upper surface of the substrate layer to obtain an initial substrate structure; the first stress compensation layer is located at the top of the initial substrate structure.

[0014] In some possible embodiments,

[0015] Providing an initial substrate structure, including:

[0016] providing a substrate layer;

[0017] A first stress compensation layer is formed on the lower surface of the substrate layer by a deposition method to obtain an initial substrate structure; the substrate layer is located on the top of the initial substrate structure.

[0018] In some possible embodiments,

[0019] The material of the first stress compensation layer includes one of silicon dioxide, amorphous silicon, polycrystalline silicon or silicon nitride, and the thickness of the first stress compensation layer is 0.1-10 microns;

[0020] The material of the second stress compensation layer includes one of silicon dioxide, amorphous silicon, polycrystalline silicon or silicon nitride, and the thickness of the second stress compensation layer is 0.1-10 microns;

[0021] The thickness of the first stress compensation layer is less than the thickness of the second stress compensation layer;

[0022] The material of the optical isolation layer includes one of silicon dioxide, fused quartz, polycrystalline quartz crystal material or single crystal quartz crystal material, and the thickness of the optical isolation layer is 26-200 microns.

[0023] In some possible embodiments,

[0024] The material of the substrate layer includes one of silicon, silicon carbide or sapphire.

[0025] In some possible embodiments,

[0026] An optical isolation layer is formed on the upper surface of the initial substrate structure by a vapor deposition process, comprising:

[0027] An optical isolation layer is formed on the upper surface of the initial substrate structure by a chemical vapor deposition process; the deposition time of the vapor deposition process is 10-300 minutes; or;

[0028] An optical isolation layer is formed on the upper surface of the initial substrate structure by using a physical vapor deposition process; the deposition time of the vapor deposition process is 10-300 minutes.

[0029] In some possible embodiments,

[0030] The photoelectric functional layer is formed on the optical isolation layer, and the initial substrate structure is post-processed to obtain a semiconductor substrate structure, including:

[0031] Providing optoelectronic materials;

[0032] Ion implantation is performed on the upper surface of the photoelectric material to form an ion implantation layer; the ion implantation layer is located inside the photoelectric material;

[0033] Bonding the ion-implanted photoelectric material to the optical isolation layer to obtain a bonded body;

[0034] Annealing the bonded body to dissociate the bonded body from the inside of the ion implantation layer to obtain a substrate structure intermediate;

[0035] The substrate structure intermediate is post-processed to obtain a semiconductor substrate structure; the remaining optoelectronic material forms a optoelectronic functional layer.

[0036] In some possible embodiments,

[0037] Post-processing the substrate structure intermediate to obtain a semiconductor substrate structure, including:

[0038] removing the remaining ion implantation layer;

[0039] Planarizing the remaining optoelectronic material;

[0040] The thickness of the first stress compensation layer is adjusted to obtain a semiconductor substrate structure; the curvature of the semiconductor substrate structure ranges from -50 microns to +50 microns.

[0041] In some possible embodiments,

[0042] The material of the photoelectric functional layer is one of lithium niobate, lithium tantalate or barium titanate;

[0043] The thickness of the photoelectric functional layer is 0.2-10 microns.

[0044] In a second aspect, an embodiment of the present application discloses a semiconductor substrate structure, characterized in that it includes:

[0045] An initial substrate structure; the initial substrate structure comprises a substrate layer;

[0046] An optical isolation layer located on the initial substrate structure; the optical refractive index of the optical isolation layer is less than 1.8, and the dielectric constant of the optical isolation layer is less than 6;

[0047] The photoelectric functional layer is located on the optical isolation layer.

[0048] In a third aspect, an embodiment of the present application discloses an electro-optic modulator, comprising the above-mentioned semiconductor substrate structure.

[0049] The technical solution provided by the embodiment of the present application has the following technical effects:

[0050] The method for forming a semiconductor substrate structure of an embodiment of the present application includes: providing an initial substrate structure; the initial substrate structure includes a substrate layer; forming an optical isolation layer on the upper surface of the initial substrate structure by a vapor deposition process; the optical refractive index of the optical isolation layer is less than 1.8, and the dielectric constant of the optical isolation layer is less than 6; the temperature of the vapor deposition process is lower than 200 degrees Celsius; forming a photoelectric functional layer on the upper surface of the optical isolation layer, and post-processing the initial substrate structure to obtain a semiconductor substrate structure. In the embodiment of the present application, a vapor deposition process is used to form an ultra-thick optical isolation layer with a low dielectric constant on the initial substrate structure to increase the propagation speed of microwaves, thereby achieving speed matching between microwaves and light waves. This method can quickly prepare a semiconductor substrate structure, and the electro-optical modulator prepared using the semiconductor substrate structure can have both high bandwidth and low half-wave voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0052] Figure 1 It is a schematic flow chart of a method for forming a semiconductor substrate structure provided in an embodiment of the present application;

[0053] Figure 2-4 , 7, 9-12 and 14-15 are structural schematic diagrams of a semiconductor substrate structure in a formation process provided by an embodiment of the present application;

[0054] Figure 5 This is a schematic diagram of a method for forming an initial substrate structure provided in an embodiment of the present application. Figure 1 ;

[0055] Figure 6 This is a schematic diagram of a method for forming an initial substrate structure provided in an embodiment of the present application. Figure 2 ;

[0056] Figure 8 It is a schematic flow chart of a method for forming a photoelectric functional layer on an optical isolation layer and performing post-processing on an initial substrate structure provided in an embodiment of the present application;

[0057] Fig.13 It is a flow chart of a method for post-processing a substrate structure intermediate to obtain a semiconductor substrate structure provided in an embodiment of the present application. DETAILED DESCRIPTION

[0058] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0059] It should be noted that the "one embodiment" or "embodiment" referred to in the specification of the embodiment of the present application refers to a specific feature, structure or characteristic that can be included in at least one implementation of the present application. It should be understood that in the specification and claims of the embodiment of the present application and the above-mentioned drawings, the orientation or position relationship indicated by the terms "upper", "lower", "top", "bottom", etc. is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. The terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" can explicitly or implicitly include one or more of the features. Moreover, the terms "first", "second", etc. are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described here can be implemented in an order other than those illustrated or described here. In addition, in the description of the present embodiment, unless otherwise specified, "plurality" means two or more. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system or product including a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0060] It should be understood that when an element or layer is referred to as "on ...", "adjacent to ...", "connected to" or "coupled to" other elements or layers, it can be directly on, adjacent to, connected to or coupled to other elements or layers, or there can be intervening elements or layers. On the contrary, when an element is referred to as "directly on ...", "directly adjacent to ...", "directly connected to" or "directly coupled to" other elements or layers, there is no intervening element or layer. It should be understood that although the terms first, second, third, etc. can be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present application, the first element, component, region, layer or part discussed below can be represented as the second element, component, region, layer or part. And when the second element, component, region, layer or part is discussed, it does not indicate that the present application necessarily has the first element, component, region, layer or part.

[0061] In order to make the purpose, technical solution and advantages disclosed in the embodiments of the present application more clear, the embodiments of the present application are further described in detail in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the embodiments of the present application and are not used to limit the embodiments of the present application.

[0062] Photoelectric materials with excellent electro-optical effects, such as lithium niobate or lithium tantalate, are one of the core materials for preparing electro-optic modulators, and these photoelectric materials mostly exist in electro-optic modulators in the form of piezoelectric single crystal thin film materials on insulators.

[0063] The piezoelectric single crystal thin film material on an insulator in the prior art is a photoelectric structure composed of a substrate structure and a photoelectric functional layer located on the substrate structure, wherein the substrate structure includes a substrate layer, and the material of the photoelectric functional layer is a photoelectric material. The bandwidth of the electro-optic modulator prepared using this photoelectric structure is limited by the substrate loss of microwaves and the electrode loss of microwaves. In order to ensure that the electro-optic modulator has a smaller half-wave voltage, it is usually necessary to set a smaller electrode spacing (such as about 3-6 microns), which will cause a larger electrode loss of microwaves, thereby limiting the improvement of the bandwidth of the electro-optic modulator. In order to overcome this technical defect, the electrode structure can be set to a T-type electrode structure, but the T-type electrode structure will introduce a slow wave effect, resulting in a decrease in the propagation speed of microwaves on the photoelectric structure, making it difficult for light waves and microwaves to achieve speed matching in the photoelectric structure.

[0064] When the speeds of light waves and microwaves match, the electro-optic modulator can maintain efficient modulation performance in a wider frequency range, so speed matching helps to improve bandwidth. Conversely, when the speeds of light waves and microwaves do not match, the bandwidth of the electro-optic modulator will drop significantly. Therefore, it is necessary to improve the structure of the piezoelectric single crystal thin film material on an insulator in the prior art to increase the propagation speed of microwaves and achieve speed matching between microwaves and light waves, so that the electro-optic modulator prepared by the optoelectronic structure has both low half-wave voltage and high bandwidth.

[0065] Usually, the propagation speed of microwaves in optoelectronic structures is related to the equivalent refractive index of the optoelectronic structure. The larger the equivalent refractive index, the lower the propagation speed of microwaves. The equivalent refractive index of a material is related to the equivalent dielectric constant of the material. The larger the equivalent dielectric constant, the larger the equivalent refractive index. The equivalent refractive index of an optoelectronic structure composed of a single material is related to the dielectric constant of the single material. The equivalent refractive index of an optoelectronic structure composed of multiple stacked materials is related to the dielectric constant of each layer of material and the thickness of each layer of material. Therefore, in order to increase the propagation speed of microwaves in optoelectronic structures, it is possible to choose to reduce the equivalent dielectric constant of the optoelectronic structure. In order to reduce the equivalent dielectric constant of the optoelectronic structure, if it is not appropriate to change the optoelectronic functional layer (optoelectronic material) that has an important impact on the electro-optical modulator, it is possible to choose to change the type and thickness of materials other than the optoelectronic material.

[0066] Based on this idea, forming a thicker optical isolation layer made of low dielectric constant material between the substrate layer and the optoelectronic functional layer is undoubtedly a suitable solution.

[0067] When the material of the substrate layer is a widely used silicon material, considering that silicon dioxide is a low dielectric constant material, an ultra-thick silicon dioxide material can be formed on the silicon substrate layer as an optical isolation layer.

[0068] Prior art mostly adopts thermal oxidation method to prepare ultra-thick silicon dioxide on silicon material, and this method generally generates silicon dioxide of the same thickness on the front and back of silicon. Due to the mismatch of thermal expansion coefficient of silicon dioxide and silicon, and the high thermal oxidation temperature (higher than 800 degrees Celsius), there is a large thermal stress between silicon dioxide and silicon. If the silicon dioxide on the back of silicon needs to be removed during subsequent chip processing, the chip will be in a stress mismatch state, thereby causing a large warpage. Therefore, it is difficult for prior art to realize the preparation process that the front of silicon has thicker silicon dioxide and the back of silicon has no silicon dioxide or only thin silicon dioxide. In addition, due to the thermal mismatch of silicon and silicon dioxide, defects will be generated at the interface of silicon and silicon dioxide in the process of preparing thicker silicon dioxide, resulting in the difficulty in realizing the preparation of silicon dioxide exceeding 10 microns of thickness.

[0069] In addition, as the thickness of the oxide increases, the speed at which oxygen diffuses into the silicon material is greatly reduced, thereby significantly reducing the speed of thermal oxidation. Existing data show that the oxidation time required to prepare 5 micron thick silicon dioxide is about 100 hours, the oxidation time required to prepare 10 micron thick silicon dioxide is about 240 hours, and the oxidation time required to prepare 15 micron thick silicon dioxide is about 400 hours. Therefore, the technology of preparing ultra-thick silicon dioxide by thermal oxidation still has the problem of low efficiency in large-scale production in actual production, making it difficult to achieve industrial application.

[0070] Based on the above solution and avoiding the technical problems that may arise in the solution, the present application provides a method for forming a semiconductor substrate structure. The semiconductor substrate structure prepared by the formation method is an optoelectronic structure obtained by improving the problems existing in the above optoelectronic structure.

[0071] Figure 1 FIG. 1 is a flow chart of a method for forming a semiconductor substrate structure provided in an embodiment of the present application. Figure 1 As shown, the flow chart at least includes the following steps S101-S103:

[0072] In step S101 , an initial substrate structure is provided; the initial substrate structure includes a substrate layer.

[0073] Figure 2-4 This is a schematic diagram of a semiconductor substrate structure formed in an embodiment of the present application. Figures 1 to 3 .

[0074] In the present application embodiment, Figure 3 As shown, the initial substrate structure 100 is composed of a first stress compensation layer 102 , a substrate layer 101 located on the first stress compensation layer 102 , and a second stress compensation layer 103 located on the substrate layer 101 .

[0075] In some possible embodiments, Figure 2 As shown, the initial substrate structure 100 consists of only a substrate layer 101 .

[0076] In some possible embodiments, Figure 4 As shown, the initial substrate structure 100 is composed of a first stress compensation layer 102 and a substrate layer 101 located on the first stress compensation layer 102 .

[0077] In the embodiment of the present application, the material of the substrate layer 101 is silicon, silicon carbide or sapphire.

[0078] In some possible embodiments, the thickness of the substrate layer 101 is 300-750 microns.

[0079] Optionally, the thickness of the substrate layer 101 is 300 micrometers; optionally, the thickness of the substrate layer 101 is 525 micrometers; optionally, the thickness of the substrate layer 101 is 750 micrometers.

[0080] Figure 5 This is a schematic diagram of a method for forming an initial substrate structure provided in an embodiment of the present application. Figure 1 .like Figure 5 As shown, the flow chart includes the following steps S501-S502:

[0081] In step S501 , a substrate layer is provided.

[0082] In step S502, a first stress compensation layer is formed on the lower surface of the substrate layer and a second stress compensation layer is formed on the upper surface of the substrate layer by a deposition method to obtain an initial substrate structure; the first stress compensation layer is located on the top of the initial substrate structure.

[0083] In the embodiment of the present application, Figure 2 Based on the substrate layer 101 shown in FIG. 1 , a first stress compensation layer 102 is formed on the lower surface of the substrate layer 101 by a deposition method, and a second stress compensation layer 103 is formed on the upper surface of the substrate layer 101, so as to obtain Figure 3 The initial substrate structure 100 is shown. The first stress compensation layer 102 and the second stress compensation layer 103 are formed simultaneously, and the first stress compensation layer 102 and the second stress compensation layer 103 have the same composition and thickness. In subsequent processes, the thickness of the first stress compensation layer 102 can be adjusted as needed.

[0084] In the embodiment of the present application, the materials of the first stress compensation layer 102 and the second stress compensation layer 103 are both silicon dioxide.

[0085] In some possible embodiments, the material of the first stress compensation layer 102 and the second stress compensation layer 103 may also be silicon nitride.

[0086] In some possible embodiments, the thickness of the first stress compensation layer 102 is 0.1-10 microns. Optionally, the thickness of the first stress compensation layer 102 is 0.1 microns; Optionally, the thickness of the first stress compensation layer 102 is 5 microns; Optionally, the thickness of the first stress compensation layer 102 is 10 microns.

[0087] In some possible embodiments, the thickness of the second stress compensation layer 103 is 0.1-10 micrometers. Optionally, the thickness of the second stress compensation layer 103 is 0.1 micrometers; Optionally, the thickness of the second stress compensation layer 103 is 5 micrometers; Optionally, the thickness of the second stress compensation layer 103 is 10 micrometers.

[0088] Figure 6This is a schematic diagram of a method for forming an initial substrate structure provided in an embodiment of the present application. Figure 2 .like Figure 6 As shown, the flow chart includes the following steps S601-S602:

[0089] In step S601 , a substrate layer is provided.

[0090] In step S602, a first stress compensation layer is formed on the lower surface of the substrate layer by a deposition method to obtain an initial substrate structure; the substrate layer is located on the top of the initial substrate structure.

[0091] In some possible embodiments, Figure 2 Based on the substrate layer 101 shown in FIG. 1 , a first stress compensation layer 102 is formed on the lower surface of the substrate layer 101 by a deposition method, and the following is obtained: Figure 4 The initial substrate structure 100 is shown. In subsequent processes, the thickness of the first stress compensation layer 102 can be adjusted as needed.

[0092] In some possible embodiments, the material of the first stress compensation layer 102 is silicon dioxide, amorphous silicon, polysilicon or silicon nitride.

[0093] In some possible embodiments, the thickness of the first stress compensation layer 102 is 0.1-10 microns. Optionally, the thickness of the first stress compensation layer 102 is 0.1 microns; Optionally, the thickness of the first stress compensation layer 102 is 5 microns; Optionally, the thickness of the first stress compensation layer 102 is 10 microns.

[0094] In step S102, an optical isolation layer is formed on the upper surface of the initial substrate structure by a vapor deposition process; the optical refractive index of the optical isolation layer is less than 1.8, and the dielectric constant of the optical isolation layer is less than 6; the temperature of the vapor deposition process is lower than 200 degrees Celsius.

[0095] Figure 7 This is a schematic diagram of a semiconductor substrate structure formed in an embodiment of the present application. Figure 4 .

[0096] In the embodiment of the present application, Figure 3 Based on the initial substrate structure 100 shown in FIG. 1 , an optical isolation layer 200 is formed on the upper surface of the second stress compensation layer 103 by using a chemical vapor deposition process to obtain a structure as shown in FIG. Figure 7 The structure shown in FIG. 1 is shown in FIG. 1 , wherein the deposition time of the vapor deposition process is 10-300 minutes, and the temperature of the vapor deposition process is lower than 200 degrees Celsius.

[0097] In some possible embodiments, a physical vapor deposition process is used to form the optical isolation layer 200 on the upper surface of the second stress compensation layer 103. The deposition time of the vapor deposition process is 10-300 minutes, and the temperature of the vapor deposition process is lower than 200 degrees Celsius.

[0098] In the embodiment of the present application, in order to increase the propagation speed of microwaves, a material with low optical refractive index and low dielectric constant is selected as the optical isolation layer 200. The optical refractive index of the formed optical isolation layer 200 is less than 1.8 and the dielectric constant is less than 6.

[0099] In the embodiment of the present application, the material of the optical isolation layer 200 is one of silicon dioxide, fused quartz, polycrystalline quartz crystal material or single crystal quartz crystal material.

[0100] In some possible embodiments, the optical isolation layer 200 has a thickness of 26-200 micrometers.

[0101] Optionally, the thickness of the optical isolation layer 200 is 26 micrometers; optionally, the thickness of the optical isolation layer 200 is 113 micrometers; optionally, the thickness of the optical isolation layer 200 is 200 micrometers.

[0102] In some possible embodiments, select Figure 4 The initial substrate structure 100 shown in FIG. 1 is used to form an optical isolation layer 200 on the upper surface of the substrate layer 101 using a chemical vapor deposition process or a vapor deposition process. Alternatively, Figure 2 In the initial substrate structure 100 shown, an optical isolation layer 200 is formed on the upper surface of the substrate layer 101 by using a chemical vapor deposition process or a vapor deposition process.

[0103] In step S103, a photoelectric functional layer is formed on the upper surface of the optical isolation layer, and the initial substrate structure is post-processed to obtain a semiconductor substrate structure.

[0104] Figure 8 1 is a flow chart of a method for forming a photoelectric functional layer on an optical isolation layer and performing post-processing on an initial substrate structure provided by an embodiment of the present application. Figure 8 As shown, the flow chart at least includes the following steps S801-S805:

[0105] In step S801 , a photoelectric material is provided.

[0106] In the embodiment of the present application, the optoelectronic material 300 is a material having a significant electro-optical effect, such as lithium niobate, lithium tantalate or barium titanate.

[0107] In step S802, ions are implanted into the upper surface of the photoelectric material to form an ion implantation layer; the ion implantation layer is located inside the photoelectric material.

[0108] Fig. 9 This is a schematic diagram of a semiconductor substrate structure formed in an embodiment of the present application. Figure 5 .

[0109] In the embodiment of the present application, ion implantation is performed on the upper surface of the photoelectric material 300 to form an ion implantation layer 301 inside the photoelectric material 300, and the photoelectric material 300 is formed as follows: Fig. 9 The position of the ion implantation layer 301 in the photoelectric material 300 can be controlled by controlling the parameters of the ion implantation, so that the thickness of the photoelectric thin film layer located above the ion implantation layer 301 can be adjusted.

[0110] In some possible embodiments, the ion species of the ion implantation include at least one of hydrogen ions and helium ions. The energy of the ion implantation is 30 to 300 keV. The dose of the ion implantation is 10 16 to 5×10 16 Pieces / square centimeter.

[0111] Optionally, the energy of the ion implantation is 30 keV; optionally, the energy of the ion implantation is 165 keV; optionally, the energy of the ion implantation is 300 keV.

[0112] Optionally, the ion implantation dose is 10 16 / cm2; the ion implantation dose is 3×10 16 / cm2; the ion implantation dose is 5×10 16 Pieces / square centimeter.

[0113] In step S803, the photoelectric material after ion implantation is bonded to the optical isolation layer to obtain a bonded body.

[0114] Fig.10 This is a schematic diagram of a semiconductor substrate structure formed in an embodiment of the present application. Figure 6 .

[0115] In the embodiment of the present application, the wafer bonding method is used. Fig. 9 The photovoltaic thin film layer in the photovoltaic material 300 after ion implantation is similar to the photovoltaic thin film layer in the photovoltaic material 300 shown in FIG. Figure 7 The optical isolation layer 200 in the structure shown is bonded to obtain Fig.10 The bonded body shown.

[0116] In step S804, the bonded body is annealed to dissociate the bonded body from the inside of the ion implantation layer, thereby obtaining a substrate structure intermediate.

[0117] Fig.11This is a schematic diagram of a semiconductor substrate structure formed in an embodiment of the present application. Figure 7 .

[0118] In the present application embodiment, Fig.10 As the annealing process proceeds, the bond body dissociates from the inside of the ion implantation layer 301, part of the ion implantation layer 301 and the photoelectric material 300 located above the ion implantation layer 301 will separate from the bond body, and the photoelectric thin film layer will be transferred to the bond body along with the remaining ion implantation layer 301, and the bond body shown in FIG. Fig.11 The substrate structure intermediate is shown.

[0119] In some possible embodiments, the annealing temperature is 200-1000 degrees Celsius, and the annealing time is 1-50 hours.

[0120] Optionally, the annealing temperature is 200 degrees Celsius; optionally, the annealing temperature is 600 degrees Celsius; optionally, the annealing temperature is 1000 degrees Celsius.

[0121] Optionally, the annealing time is 1 hour; optionally, the annealing time is 25.5 hours; optionally, the annealing time is 50 hours.

[0122] In step S805, the substrate structure intermediate is post-processed to obtain a semiconductor substrate structure; the remaining optoelectronic material forms a optoelectronic functional layer.

[0123] Fig.12 This is a schematic diagram of a semiconductor substrate structure formed in an embodiment of the present application. Figure 8 .

[0124] Fig.13 1 is a flow chart of a method for post-processing a substrate structure intermediate to obtain a semiconductor substrate structure provided by an embodiment of the present application. Fig.13 As shown, the flow chart at least includes the following steps S1301-S1303:

[0125] In step S1001 , the remaining ion implantation layer is removed.

[0126] In step S1002 , the remaining photoelectric material is planarized.

[0127] In step S1003, the thickness of the first stress compensation layer is adjusted to obtain a semiconductor substrate structure; the curvature of the semiconductor substrate structure ranges from -50 microns to +50 microns.

[0128] In the embodiment of the present application, etching or the like is used to remove the remaining ion implantation layer 301, and chemical mechanical polishing is used to planarize and adjust the thickness of the photoelectric thin film layer, so that the remaining photoelectric thin film layer becomes a photoelectric functional layer 302 of the required thickness. Finally, the thickness of the first stress compensation layer 102 is adjusted to change the morphology of the semiconductor substrate structure, thereby obtaining Fig.12 The semiconductor substrate structure shown has high flatness.

[0129] In the embodiment of the present application, the thickness of the first stress compensation layer 102 can be flexibly adjusted according to the thickness of the optical isolation layer 200. The thickness of the first stress compensation layer 102 after thickness adjustment is less than the thickness of the second stress compensation layer 103.

[0130] In the embodiment of the present application, the curvature of the semiconductor substrate structure ranges from -50 microns to +50 microns. When the curvature is a negative value, it indicates that the surface of the semiconductor substrate structure is concave; when the curvature is a positive value, it indicates that the surface of the semiconductor substrate structure is convex. The curvature of the semiconductor substrate structure prepared by the formation method provided by the present application is greatly reduced, which helps to improve the modulation performance of the electro-optic modulator prepared by the semiconductor substrate structure.

[0131] In some possible embodiments, the material of the photoelectric functional layer 302 is lithium niobate, lithium tantalate or barium titanate.

[0132] In some possible embodiments, the thickness of the optoelectronic functional layer 302 is 0.2-10 micrometers.

[0133] Optionally, the thickness of the photoelectric functional layer 302 is 0.2 micrometers; optionally, the thickness of the photoelectric functional layer 302 is 5.1 micrometers; optionally, the thickness of the photoelectric functional layer 302 is 10 micrometers.

[0134] In the embodiment of the present application, Fig.12 In the structure shown in FIG. 1 , there is a case where the materials of the second stress compensation layer 103 and the optical isolation layer 200 are both silicon dioxide. In this case, the second stress compensation layer 103 can be regarded as a part of the optical isolation layer 200 .

[0135] Fig.14 and Fig.15 This is a schematic diagram of a semiconductor substrate structure formed in an embodiment of the present application. Figure 9 and ten .

[0136] In some possible embodiments, when selecting Figure 4 When the initial substrate structure 100 is shown, the final result can be as follows Fig.14 The semiconductor substrate structure shown.

[0137] In some possible embodiments, when selecting Figure 2 When the initial substrate structure 100 is shown, the final result can be as follows Fig.15 The semiconductor substrate structure shown.

[0138] In the embodiment of the present application, a first stress compensation layer 102 is prepared in the initial substrate structure 100. By adjusting the thickness of the first stress compensation layer 102, the morphology of the semiconductor substrate structure can be changed, thereby obtaining a semiconductor substrate structure with high flatness.

[0139] In the embodiment of the present application, the ultra-thick optical isolation layer 200 with a low dielectric constant is formed on the initial substrate structure 100 to increase the propagation speed of microwaves, thereby achieving speed matching between microwaves and light waves. By achieving speed matching between microwaves and light waves, the electro-optic modulator made from the semiconductor substrate structure can have a low half-wave voltage and a high bandwidth.

[0140] In the embodiment of the present application, a vapor deposition process is used to form an ultra-thick optical isolation layer 200 with a low dielectric constant on the initial substrate structure 100, so that a semiconductor substrate structure can be quickly prepared in a short time, and the electro-optic modulator prepared using the semiconductor substrate structure can have both high bandwidth and low half-wave voltage.

[0141] The present application also provides a semiconductor substrate structure. Fig.15 As shown, the semiconductor substrate structure includes an initial substrate structure 100, an optical isolation layer 200 located on the initial substrate structure 100, and an optoelectronic functional layer 302 located on the optical isolation layer 200. The initial substrate structure 100 includes a substrate layer 101, the optical refractive index of the optical isolation layer 200 is less than 1.8, and the dielectric constant of the optical isolation layer 200 is less than 6.

[0142] In the embodiment of the present application, the curvature of the semiconductor substrate structure ranges from -50 microns to +50 microns.

[0143] In the embodiment of the present application, the material of the substrate layer 101 is single crystal silicon, and the thickness of the substrate layer 101 is 350-800 microns. The material of the optical isolation layer 200 includes one of silicon dioxide, fused quartz, polycrystalline quartz crystal material or single crystal quartz crystal material, and the thickness of the optical isolation layer 200 is 26-200 microns. The material of the photoelectric functional layer 302 is one of lithium niobate, lithium tantalate or barium titanate, and the thickness of the photoelectric functional layer 302 is 0.2-10 microns.

[0144] In some possible embodiments, the semiconductor substrate structure further includes a first stress compensation layer 102 located below the substrate layer 101. Fig.14The structure shown in the figure. The material of the first stress compensation layer 102 is silicon dioxide, amorphous silicon, polysilicon or silicon nitride, and the thickness of the first stress compensation layer 102 is 0.1-10 microns.

[0145] In some possible embodiments, the semiconductor substrate structure further includes a first stress compensation layer 102 located below the substrate layer 101 and a second stress compensation layer 103 located above the substrate layer 101. Fig.12 The structure shown in FIG. 1 is a structure shown in FIG. 1. The first stress compensation layer 102 and the second stress compensation layer 103 are made of the same material, which can be silicon dioxide or silicon nitride. The thickness of the first stress compensation layer 102 is 0.1-10 microns, and the thickness of the second stress compensation layer 103 is 0.1-10 microns.

[0146] In the embodiment of the present application, the semiconductor substrate structure is prepared by the above-mentioned method for forming a semiconductor substrate structure.

[0147] The embodiment of the present application also provides an electro-optic modulator. The electro-optic modulator includes the semiconductor substrate structure and a T-shaped electrode structure located on the semiconductor substrate structure. The electro-optic modulator has both high bandwidth and low half-wave voltage.

[0148] It should be noted that the above-mentioned sequence of the embodiments of the present application is for description only and does not represent the advantages and disadvantages of the embodiments. The above-mentioned specific embodiments of this specification are described. Other embodiments are within the scope of the attached claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0149] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0150] A person skilled in the art will understand that all or part of the steps to implement the above embodiments may be accomplished by hardware or by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a disk or an optical disk, etc.

[0151] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for forming a semiconductor substrate structure, characterized in that: include: providing an initial substrate structure; The initial substrate structure includes a substrate layer; forming an optical isolation layer on the upper surface of the initial substrate structure by a vapor deposition process; The optical refractive index of the optical isolation layer is less than 1.8, and the dielectric constant of the optical isolation layer is less than 6; the temperature of the vapor deposition process is lower than 200 degrees Celsius; A photoelectric functional layer is formed on the upper surface of the optical isolation layer, and the initial substrate structure is post-processed to obtain a semiconductor substrate structure.

2. The method for forming a semiconductor substrate structure according to claim 1, characterized in that: The providing of an initial substrate structure comprises: providing the substrate layer; A first stress compensation layer is formed on the lower surface of the substrate layer by a deposition method, and a second stress compensation layer is formed on the upper surface of the substrate layer to obtain the initial substrate structure; the first stress compensation layer is located at the top of the initial substrate structure.

3. The method for forming a semiconductor substrate structure according to claim 1, characterized in that: The providing of an initial substrate structure comprises: providing the substrate layer; A first stress compensation layer is formed on the lower surface of the substrate layer by a deposition method to obtain the initial substrate structure; the substrate layer is located on the top of the initial substrate structure.

4. The method for forming a semiconductor substrate structure according to claim 2, wherein: The material of the first stress compensation layer includes one of silicon dioxide, amorphous silicon, polycrystalline silicon or silicon nitride, and the thickness of the first stress compensation layer is 0.1-10 microns; The material of the second stress compensation layer includes one of silicon dioxide, amorphous silicon, polycrystalline silicon or silicon nitride, and the thickness of the second stress compensation layer is 0.1-10 microns; The thickness of the first stress compensation layer is less than the thickness of the second stress compensation layer; The material of the optical isolation layer includes one of silicon dioxide, fused quartz, polycrystalline quartz crystal material or single crystal quartz crystal material, and the thickness of the optical isolation layer is 26-200 microns.

5. The method for forming a semiconductor substrate structure according to any one of claims 1 to 3, characterized in that: The material of the substrate layer includes one of silicon, silicon carbide or sapphire.

6. The method for forming a semiconductor substrate structure according to any one of claims 1 to 3, characterized in that: The method of forming an optical isolation layer on the upper surface of the initial substrate structure by using a vapor deposition process comprises: An optical isolation layer is formed on the upper surface of the initial substrate structure by a chemical vapor deposition process; the deposition time of the vapor deposition process is 10-300 minutes; or; An optical isolation layer is formed on the upper surface of the initial substrate structure by using a physical vapor deposition process; the deposition time of the vapor deposition process is 10-300 minutes.

7. The method for forming a semiconductor substrate structure according to claim 6, wherein: The step of forming a photoelectric functional layer on the optical isolation layer and performing post-processing on the initial substrate structure to obtain a semiconductor substrate structure comprises: Providing optoelectronic materials; Performing ion implantation on the upper surface of the photoelectric material to form an ion implantation layer; the ion implantation layer is located inside the photoelectric material; Bonding the photoelectric material after ion implantation to the optical isolation layer to obtain a bonded body; Annealing the bonded body to dissociate the bonded body from the inside of the ion implantation layer to obtain a substrate structure intermediate; The substrate structure intermediate is post-processed to obtain the semiconductor substrate structure; the remaining optoelectronic material forms the optoelectronic functional layer.

8. The method for forming a semiconductor substrate structure according to claim 7, characterized in that: The post-processing of the substrate structure intermediate to obtain the semiconductor substrate structure comprises: removing the remaining ion implantation layer; Planarizing the remaining optoelectronic material; The thickness of the first stress compensation layer is adjusted to obtain the semiconductor substrate structure; the curvature of the semiconductor substrate structure ranges from -50 microns to +50 microns.

9. The method for forming a semiconductor substrate structure according to claim 1, wherein: The material of the photoelectric functional layer is one of lithium niobate, lithium tantalate or barium titanate; The thickness of the photoelectric functional layer is 0.2-10 microns.

10. A semiconductor substrate structure, characterized in that: include: Initial substrate structure; The initial substrate structure includes a substrate layer; an optical isolation layer located on the initial substrate structure; The optical refractive index of the optical isolation layer is less than 1.8, and the dielectric constant of the optical isolation layer is less than 6; The photoelectric functional layer is located on the optical isolation layer.

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