Heterogeneous composite substrate and manufacturing method thereof

Abstract

The invention provides a heterogeneous composite substrate and a manufacturing method thereof, and the manufacturing method comprises the steps: (1) carrying out the O ion implantation of a Si substrate, forming an O implantation layer, carrying out the C ion implantation, forming a C implantation layer on the O implantation layer, and obtaining a composite substrate precursor; (2) annealing and repairing the composite substrate precursor to convert the O injection layer into a SiO2 layer and convert the C injection layer into a SiC layer at the same time, and then performing post-processing to obtain a composite substrate; the composite substrate comprises a Si layer, a SiO2 layer and a SiC layer which are stacked in sequence; and (3) bonding the surface of one side, far away from the SiO2 layer, of the SiC layer in the composite substrate with the to-be-bonded surface of the SiC substrate to obtain the heterogeneous composite substrate. By adopting the method provided by the invention, the bonding strength of the heterogeneous composite substrate can be improved, and the quality of the heterogeneous composite substrate can be improved.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductors and relates to a heterogeneous composite substrate and a manufacturing method thereof. Background Art

[0002] Semiconductor materials are the basis for making semiconductor devices and integrated circuits. As people vigorously develop technologies such as 5G, the Internet of Things, and the Industrial Internet, traditional materials can no longer meet the new requirements of high temperature, high power, high voltage, high frequency, and radiation resistance. Therefore, the third-generation semiconductors have entered people's field of vision. Represented by silicon carbide, a typical material of the third-generation semiconductor, compared with silicon-based materials, silicon carbide has a larger bandgap, a stronger critical breakdown electric field, and a higher thermal conductivity. The bandgap of silicon carbide is about 3 times that of Si, the critical breakdown electric field is about 10 times that of Si, and the thermal conductivity is about 3 times that of Si. In addition, due to the characteristics of silicon carbide such as high elastic modulus, high fracture strength, and high sound velocity, the application of silicon carbide in microelectromechanical systems (MEMS) has also attracted more and more attention, such as radio frequency communications, sensors, and nanophotonic structures.

[0003] Although the third-generation semiconductors have many advantages, their slow crystal growth speed, low yield and difficulty in diameter expansion have resulted in low production capacity and very high prices. In order to increase production capacity and reduce costs, a composite substrate structure is proposed. Silicon carbide on insulator (SiCOI) heterogeneous composite substrate structure is often used in MEMS systems. SiCOI is a structure that uses an insulating layer to isolate silicon carbide from a silicon substrate, and the insulating layer is usually SiO2.

[0004] However, heterogeneous composite substrates usually face important problems, namely large lattice mismatch and thermal expansion mismatch, which may lead to slip defects and excessive defect density at the interface of heterogeneous composite substrates, thus greatly reducing the performance of subsequent devices. Therefore, how to improve lattice mismatch and thermal expansion mismatch is a technical problem that needs to be solved urgently. Summary of the invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a heterogeneous composite substrate and a method for manufacturing the same. The present invention introduces a SiC layer as a buffer layer, which can significantly improve the lattice mismatch and thermal expansion mismatch problems of the heterogeneous composite substrate, thereby effectively improving the interface defects (such as slip defects) of the heterogeneous composite substrate and reducing the defect density of the heterogeneous composite substrate.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a method for manufacturing a heterogeneous composite substrate, the manufacturing method comprising:

[0008] (1) performing O ion implantation on a Si substrate to form an O implantation layer, and then performing C ion implantation to form a C implantation layer on the O implantation layer, thereby obtaining a composite substrate precursor;

[0009] (2) annealing and repairing the composite substrate precursor to transform the O-injected layer into a SiO2 layer and transform the C-injected layer into a SiC layer, and then performing post-processing to obtain a composite substrate; the composite substrate comprises a Si layer, a SiO2 layer and a SiC layer stacked in sequence;

[0010] (3) Bonding a surface of the SiC layer in the composite substrate away from the SiO2 layer to a surface to be bonded of the SiC substrate to obtain the heterogeneous composite substrate.

[0011] It should be noted that the O injection layer and the C injection layer are in contact with each other.

[0012] The present invention provides a method for manufacturing a heterogeneous composite substrate, which has the following advantages:

[0013] (1) The present invention can form a high-quality SiC layer on the SiO2 layer by means of ion implantation and annealing repair, without the need for an additional step of epitaxial deposition of SiC, thereby avoiding the problem of poor quality of epitaxially deposited SiC;

[0014] (2) The SiO2 layer and the SiC layer in the present invention are formed in the same annealing repair process, which saves time cost and process consumables, and the quality of the formed SiO2 layer and SiC layer is better than that of the SiO2 layer and SiC layer obtained by multiple annealing;

[0015] (3) The present invention bonds a high-quality SiC layer to a SiC substrate. Since the two materials have the same properties, the bonding interface problem caused by material differences can be avoided, thereby improving the bonding quality and reducing the stress generated by the thermal expansion difference at the bonding interface; the present invention introduces a SiC layer as a buffer layer, which can significantly improve the lattice mismatch and thermal expansion mismatch problems of the heterogeneous composite substrate, thereby effectively improving the interface defects (such as slip defects) of the heterogeneous composite substrate and reducing the defect density of the heterogeneous composite substrate. Therefore, the method of the present invention can improve the bonding strength of the heterogeneous composite substrate and improve the quality of the heterogeneous composite substrate.

[0016] Preferably, the specific parameters of the O ion injection include: an injection energy of 1 to 1000 keV, for example, 1 keV, 5 keV, 10 keV, 50 keV, 100 keV, 200 keV, 300 keV, 400 keV, 500 keV, 600 keV, 700 keV, 800 keV, 900 keV, 950 keV or 1000 keV, etc.; an injection dose of 1E16 to 1E18 ions / cm2 , for example, 1E16ions / cm 2 、5E16ions / cm 2 、1E17ions / cm 2 、5E17ions / cm 2 or 1E18ions / cm 2 etc.; the inclination angle is 0-60°, for example, it can be 0°, 10°, 20°, 30°, 40°, 50° or 60°, etc.; the torsion angle is 0-90°, for example, it can be 0°, 10°, 20°, 30°, 40°, 50°, 60°, 70°, 80° or 90°, etc.; the injection temperature is 20-800°C, for example, it can be 20°, 50°, 100°, 200°, 300°, 400°, 500°, 600°, 700° or 800°, etc., but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0017] Preferably, based on the O ion implantation surface of the Si substrate, the O ion implantation depth is 0.1 to 1.5 μm, for example, it can be 0.1 μm, 0.2 μm, 0.3 μm, 0.4 μm, 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm, 1 μm, 1.1 μm, 1.2 μm, 1.3 μm, 1.4 μm or 1.5 μm, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0018] Preferably, the thickness of the O injection layer is 0.1-0.9 μm, for example, 0.1 μm, 0.2 μm, 0.3 μm, 0.4 μm, 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm or 0.9 μm, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0019] Preferably, the specific parameters for injecting the C ions include: an injection energy of 1 to 1000 keV, for example, 1 keV, 5 keV, 10 keV, 50 keV, 100 keV, 200 keV, 300 keV, 400 keV, 500 keV, 600 keV, 700 keV, 800 keV, 900 keV, 950 keV or 1000 keV, etc.; an injection dose of 1E16 to 1E18 ions / cm 2 , for example, 1E16ions / cm 2 、5E16ions / cm 2 、1E17ions / cm 2 、5E17ions / cm 2 or 1E18ions / cm2 etc.; the inclination angle is 0-60°, for example, it can be 0°, 10°, 20°, 30°, 40°, 50° or 60°, etc.; the torsion angle is 0-90°, for example, it can be 0°, 10°, 20°, 30°, 40°, 50°, 60°, 70°, 80° or 90°, etc.; the injection temperature is 20-800°C, for example, it can be 20°, 50°, 100°, 200°, 300°, 400°, 500°, 600°, 700° or 800°, etc., but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0020] Preferably, the O ion implantation surface of the Si substrate and the C ion implantation surface of the Si substrate are the same surface.

[0021] Preferably, based on the C ion implantation surface of the Si substrate, the implantation depth of the C ions is 0.05 to 1.5 μm, for example, it can be 0.05 μm, 0.08 μm, 0.1 μm, 0.2 μm, 0.3 μm, 0.4 μm, 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm, 1 μm, 1.1 μm, 1.2 μm, 1.3 μm, 1.4 μm or 1.5 μm, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0022] Preferably, the implantation depth of the C ions is less than the implantation depth of the O ions.

[0023] Preferably, the thickness of the C injection layer is 0.02 to 0.9 μm, for example, it can be 0.02 μm, 0.05 μm, 0.08 μm, 0.1 μm, 0.2 μm, 0.3 μm, 0.4 μm, 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm or 0.9 μm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0024] In the present invention, by adjusting parameters such as ion implantation depth and implantation layer thickness, the composite substrate precursor has two structures. One structure is a Si layer, an O implantation layer, a C implantation layer and a Si layer stacked in sequence, wherein the Si layer in contact with the C implantation layer needs to be removed in a subsequent step; and the other structure is a Si layer, an O implantation layer and a C implantation layer stacked in sequence.

[0025] The implantation concentration distribution of C ions and O ions can be simulated based on Monte Carlo simulation related software, such as SRIM or TCAD software. The software calculates the implantation depth (range projection Rp), implantation concentration (Cp) and projection range deviation (ΔRp). These key parameters can be obtained through simulation for better design, for example, the implantation depth can be obtained through the projection range, and the layer thickness can be obtained through the projection range deviation. It is convenient to implant ions to meet the set requirements.

[0026] Preferably, the annealing repair temperature is 800-1350°C, for example, it can be 800°C, 850°C, 900°C, 950°C, 1000°C, 1050°C, 1100°C, 1150°C, 1200°C, 1250°C, 1300°C or 1350°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0027] Preferably, the annealing repair time is 10 to 500 min, for example, it can be 10 min, 20 min, 50 min, 100 min, 200 min, 300 min, 400 min or 500 min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0028] In the present invention, annealing repair is performed within a set temperature range and time range, so that the O-injection layer and the C-injection layer can be transformed simultaneously, and the SiO2 layer and the SiC layer can be obtained efficiently and at low cost.

[0029] Preferably, the annealing repair is performed in an inert atmosphere, wherein the gas in the inert atmosphere includes nitrogen or argon.

[0030] Preferably, the post-processing method includes chemical mechanical polishing (CMP).

[0031] In the present invention, when the structure of the composite substrate precursor is a Si layer, an O injection layer, a C injection layer and a Si layer stacked in sequence, after annealing and repair, the structure becomes a Si layer, a SiO2 layer, a SiC layer and a Si layer stacked in sequence, and the role of the CMP treatment is to remove the Si layer connected to the SiC layer, so that the surface of the SiC layer is exposed and the surface is flattened.

[0032] When the structure of the composite substrate precursor is a Si layer, an O injection layer and a C injection layer stacked in sequence, after annealing and repair, the structure becomes a Si layer, a SiO2 layer and a SiC layer stacked in sequence, and the role of the CMP treatment is to flatten the surface of the SiC layer.

[0033] In summary, for the two composite substrate precursor structures, after chemical mechanical polishing (CMP), what is obtained is a structure of a Si layer, a SiO2 layer and a SiC layer stacked in sequence.

[0034] Preferably, the chemical mechanical polishing time is 30 to 500 s, for example, it can be 30 s, 50 s, 80 s, 100 s, 150 s, 200 s, 250 s, 300 s, 350 s, 400 s, 450 s or 500 s, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0035] Preferably, the removal amount of the chemical mechanical polishing is For example it could be or The above range is not limited to the listed values, and other values ​​not listed within the above range are also applicable.

[0036] Preferably, in step (3), before the bonding, ion implantation is performed on the surface of the SiC substrate to be bonded to form a pre-stripping buried layer.

[0037] Preferably, the absolute vacuum degree of the bonding is ≤10 -6 Pa, for example, can be 10 -6 Pa, 10 -7 Pa or 10 -8 Pa, etc., but are not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0038] Preferably, the bonding temperature is 20-30°C, for example, it can be 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C or 30°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0039] Preferably, the bonding pressure is 10-100 kN, for example, 10 kN, 20 kN, 30 kN, 40 kN, 50 kN, 60 kN, 70 kN, 80 kN, 90 kN or 100 kN, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0040] Preferably, after the bonding, the bonded body obtained by bonding is subjected to heat treatment so that the bonded body is broken along the pre-stripping buried layer to obtain the heterogeneous composite substrate and the remaining SiC substrate.

[0041] In the present invention, by performing an ion implantation step and a post-bonding heat treatment step on the SiC substrate, a part of the SiC substrate is bonded with the composite substrate to prepare a heterogeneous composite substrate, and the remaining SiC substrate can be reused, thereby achieving effective utilization of the SiC substrate.

[0042] Preferably, the temperature of the heat treatment is 800-1200°C, for example, it can be 800°C, 850°C, 900°C, 950°C, 1000°C, 1050°C, 1100°C, 1150°C or 1200°C, etc.; the time of the heat treatment is 1-60min, for example, it can be 1min, 5min, 10min, 20min, 30min, 40min, 50min or 60min, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0043] Preferably, the heat treatment is performed under an inert atmosphere, wherein the gas in the inert atmosphere comprises nitrogen or argon.

[0044] As a preferred technical solution of the present invention, the production method specifically comprises the steps of:

[0045] (I) With one side of the Si substrate as the O ion implantation surface, the Si substrate is implanted with O ions to obtain a Si substrate having an O implantation layer; wherein the specific parameters of the O ion implantation include: an implantation energy of 1 to 1000 keV; an implantation dose of 1E16 to 1E18 ions / cm 2 ; The tilt angle is 0 to 60°; The twist angle is 0 to 90°; The injection temperature is 20 to 800°C; Based on the O ion injection surface, the O ion injection depth is 0.1 to 1.5 μm; The thickness of the O injection layer is 0.1 to 0.9 μm;

[0046] (II) The O ion implantation surface is used as a C ion implantation surface, and C ions are implanted into the Si substrate having the O implantation layer to form a C implantation layer on the O implantation layer, thereby obtaining a composite substrate precursor, wherein the composite substrate precursor is composed of a Si layer, an O implantation layer, a C implantation layer and a Si layer stacked in sequence; wherein the specific parameters for implanting the C ions include: an implantation energy of 1 to 1000 keV; an implantation dose of 1E16 to 1E18 ions / cm 2 ; The tilt angle is 0 to 60°; The twist angle is 0 to 90°; The injection temperature is 20 to 800°C; The injection depth of the C ions is 0.05 to 1.5 μm based on the C ion injection surface; The injection depth of the C ions is less than the injection depth of the O ions; The thickness of the C injection layer is 0.02 to 0.9 μm;

[0047] (III) annealing and repairing the composite substrate precursor at 800 to 1350° C. for 10 to 500 min in a nitrogen or argon atmosphere, so that the O injection layer is converted into a SiO2 layer, and the C injection layer is converted into a SiC layer, to obtain a repaired Si substrate; chemically mechanically polishing the repaired Si substrate for 30 to 500 s to remove the Si layer in contact with the SiC layer, to obtain a composite substrate, wherein the composite substrate is composed of a Si layer, a SiO2 layer and a SiC layer stacked in sequence;

[0048] (IV) Using the surface of the SiC substrate to be bonded as the ion implantation surface, hydrogen ions or helium ions are implanted into the SiC substrate to form a pre-stripping buried layer; then, -6 Pa, at a temperature of 20 to 30 ° C and a pressure of 10 to 100 kN, the surface of the SiC layer in the composite substrate away from the SiO2 layer is bonded to the surface to be bonded of the SiC substrate for 0.5 to 5 min, and then the bonded body is heat-treated at 800 to 1200 ° C for 1 to 60 min in a nitrogen or argon atmosphere, so that the bonded body is broken along the pre-stripped buried layer, and then the heterogeneous composite substrate precursor obtained after the break is annealed and repaired at 800 to 1300 ° C for 10 to 660 min in a nitrogen or argon atmosphere, and then the heterogeneous composite substrate precursor is annealed and repaired for 30 to 500 s and the amount of the pre-stripped buried layer is removed. Chemical mechanical polishing is performed to obtain the heterogeneous composite substrate and the remaining SiC substrate; wherein the specific parameters of the hydrogen ions or helium ions implanted include: an implantation energy of 1 to 1000 keV; an implantation dose of 1E16 to 1E18 ions / cm 2 ; The tilt angle is 0 to 60°; The torsion angle is 0 to 90°; The injection temperature is 20 to 600°C.

[0049] In the present invention, the heterogeneous composite substrate precursor obtained after fracture is annealed to repair the implantation damage; and then CMP treatment is performed to obtain a smooth surface.

[0050] In a second aspect, the present invention provides a heterogeneous composite substrate, which is manufactured by the manufacturing method described in the first aspect.

[0051] Preferably, the heterogeneous composite substrate comprises a Si layer, a SiO2 layer, a first SiC layer and a second SiC layer stacked in sequence, and the first SiC layer and the second SiC layer are bonded to each other.

[0052] In the present invention, the first SiC layer is obtained by the steps of C ion implantation and annealing repair; the second SiC layer is derived from a SiC substrate.

[0053] Preferably, the bonding strength between the first SiC layer and the second SiC layer is ≥1.2 J / m 2 .

[0054] The numerical range described in the present invention not only includes the point values ​​listed above, but also includes any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0055] Compared with the prior art, the present invention has the following beneficial effects:

[0056] The present invention provides a method for manufacturing a heterogeneous composite substrate, which has the following advantages:

[0057] (1) The present invention can form a high-quality SiC layer on the SiO2 layer by means of ion implantation and annealing repair, without the need for an additional step of epitaxial deposition of SiC, thereby avoiding the problem of poor quality of epitaxially deposited SiC;

[0058] (2) The SiO2 layer and the SiC layer in the present invention are formed in the same annealing repair process, which saves time cost and process consumables, and the quality of the formed SiO2 layer and SiC layer is better than that of the SiO2 layer and SiC layer obtained by multiple annealing;

[0059] (3) The present invention bonds a high-quality SiC layer to a SiC substrate. Since the two materials have the same properties, the bonding interface problem caused by material differences can be avoided, thereby improving the bonding quality and reducing the stress generated by the thermal expansion difference at the bonding interface; the present invention introduces a SiC layer as a buffer layer, which can significantly improve the lattice mismatch and thermal expansion mismatch problems of the heterogeneous composite substrate, thereby effectively improving the interface defects (such as slip defects) of the heterogeneous composite substrate and reducing the defect density of the heterogeneous composite substrate. Therefore, the method of the present invention can improve the bonding strength of the heterogeneous composite substrate and improve the quality of the heterogeneous composite substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 A process flow chart of a method for manufacturing a heterogeneous composite substrate provided in an embodiment of the present invention;

[0061] Among them, 10-SiC substrate; 11-pre-stripping buried layer; 20-Si substrate; 21-O injection layer; 22-C injection layer; 23-SiC layer; 24-SiO2 layer. DETAILED DESCRIPTION

[0062] The technical solution of the present invention is further illustrated below through specific implementation methods.

[0063] In one embodiment, the present invention provides a method for manufacturing a heterogeneous composite substrate, the process of which is as follows: Figure 1 As shown, the following steps are included:

[0064] (1) performing O ion implantation on a Si substrate 20 to form an O implantation layer 21, and then performing C ion implantation to form a C implantation layer 22 on the O implantation layer 21, thereby obtaining a composite substrate precursor, wherein the composite substrate precursor is composed of a Si layer, an O implantation layer 21, a C implantation layer 22, and a Si layer stacked in sequence;

[0065] (2) annealing and repairing the composite substrate precursor, so that the O injection layer 21 is transformed into a SiO2 layer 24, and the C injection layer 22 is transformed into a SiC layer 23, to obtain a repaired Si substrate; performing CMP treatment on the repaired Si substrate, so as to remove the Si layer in contact with the SiC layer 23, so that the surface of the SiC layer 23 is exposed, to obtain a composite substrate, wherein the composite substrate is composed of a Si layer, a SiO2 layer 24 and a SiC layer 23 stacked in sequence;

[0066] (3) using the surface of the SiC substrate 10 to be bonded as the ion implantation surface, H ions are implanted into the SiC substrate 10 to form a pre-stripping buried layer 11;

[0067] (4) Bonding a side surface of the SiC layer 23 in the composite substrate away from the SiO2 layer 24 to the surface to be bonded of the SiC substrate 10 to obtain a bonded body, and then performing heat treatment and peeling on the bonded body so that the bonded body is broken along the pre-peeled buried layer 11, and then annealing and repairing the heterogeneous composite substrate precursor obtained after the fracture and performing CMP treatment to obtain the heterogeneous composite substrate.

[0068] Example 1

[0069] This embodiment provides a method for manufacturing a heterogeneous composite substrate, comprising the following steps:

[0070] (1) With one side of the Si substrate as the O ion implantation surface, the Si substrate is implanted with O ions to obtain a Si substrate having an O implantation layer; wherein the specific parameters of the O ion implantation are: an implantation energy of 300 keV, an implantation dose of 8E17ions / cm 2 , the tilt angle is 7°, the twist angle is 23°, and the injection temperature is 650°C; based on the O ion injection surface, the injection depth of the O ions is 0.6 μm; the thickness of the O injection layer is 0.4 μm;

[0071] (2) Using the O ion implantation surface as a C ion implantation surface, implanting C ions into the Si substrate having the O implantation layer to form a C implantation layer on the O implantation layer, thereby obtaining a composite substrate precursor, wherein the composite substrate precursor is composed of a Si layer, an O implantation layer, a C implantation layer and a Si layer stacked in sequence; wherein the specific parameters for implanting the C ions are: an implantation energy of 150 keV, an implantation dose of 6E17 ions / cm 2 , the tilt angle is 7°, the twist angle is 23°, and the injection temperature is 700°C; based on the C ion injection surface, the injection depth of the C ions is 0.4 μm; the thickness of the C injection layer is 0.25 μm;

[0072] (3) annealing and repairing the composite substrate precursor at 1200° C. for 300 min in an argon atmosphere, so that the O injection layer is converted into a SiO2 layer, and the C injection layer is converted into a SiC layer, thereby obtaining a repaired Si substrate; chemically mechanically polishing the repaired Si substrate for 180 s, thereby removing the Si layer in contact with the SiC layer and exposing the surface of the SiC layer, thereby obtaining a composite substrate, wherein the composite substrate is composed of a Si layer, a SiO2 layer, and a SiC layer stacked in sequence;

[0073] (4) With the surface of the SiC substrate to be bonded as the ion implantation surface, hydrogen ions are implanted into the SiC substrate to form a pre-stripping buried layer, wherein the specific parameters of the hydrogen ion implantation are: an implantation energy of 100 keV and an implantation dose of 6E16 ions / cm 2 , the tilt angle is 7°, the twist angle is 23°, and the injection temperature is 40°C; then -6 Pa absolute vacuum, at a temperature of 26 ° C and a pressure of 50 kN, the surface of the SiC layer in the composite substrate away from the SiO2 layer is bonded to the surface to be bonded of the SiC substrate for 1 min, and then the bonded body is heat treated at 1000 ° C for 30 min in a nitrogen atmosphere, so that the bonded body is broken along the pre-stripped buried layer, and then the heterogeneous composite substrate precursor obtained after the break is annealed and repaired at 1100 ° C for 600 min in a nitrogen atmosphere, and then the time is 300 s and the amount of removal is The heterogeneous composite substrate and the remaining SiC substrate are obtained by chemical mechanical polishing.

[0074] Test: ① Measure the bonding strength of the heterogeneous composite substrate by the Opening Clack method. ② Measure the bending degree and overall warping degree of the heterogeneous composite substrate by the Tropel machine, that is, test the Bow value and Warp value.

[0075] After testing, the bonding strength of the heterogeneous composite substrate obtained in this embodiment is 1.3 J / m2 ; Bow value is 5.2μm, Warp value is 10.2μm.

[0076] Example 2

[0077] This embodiment provides a method for manufacturing a heterogeneous composite substrate, comprising the following steps:

[0078] (1) With one side of the Si substrate as the O ion implantation surface, the Si substrate is implanted with O ions to obtain a Si substrate having an O implantation layer; wherein the specific parameters of the O ion implantation are: an implantation energy of 400 keV, an implantation dose of 9.5E17ions / cm 2 , the tilt angle is 7°, the twist angle is 23°, and the injection temperature is 700°C; based on the O ion injection surface, the injection depth of the O ions is 0.8 μm; the thickness of the O injection layer is 0.6 μm;

[0079] (2) using the O ion implantation surface as a C ion implantation surface, implanting C ions into the Si substrate having the O implantation layer to form a C implantation layer on the O implantation layer, thereby obtaining a composite substrate precursor, wherein the composite substrate precursor is composed of a Si layer, an O implantation layer and a C implantation layer stacked in sequence; wherein the specific parameters for implanting the C ions are: an implantation energy of 180 keV, an implantation dose of 8E17 ions / cm 2 , the tilt angle is 7°, the twist angle is 23°, and the injection temperature is 750°C; based on the C ion injection surface, the injection depth of the C ions is 0.5 μm; the thickness of the C injection layer is 0.4 μm;

[0080] (3) Under an argon atmosphere, the composite substrate precursor is annealed at 1250° C. for 300 min to transform the O-injected layer into a SiO2 layer and the C-injected layer into a SiC layer, thereby obtaining a repaired Si substrate; the repaired Si substrate is annealed for 60 s and the amount of carbon removed is Chemical mechanical polishing is performed to flatten the surface of the SiC layer to obtain a composite substrate, wherein the composite substrate is composed of a Si layer, a SiO2 layer and a SiC layer stacked in sequence;

[0081] (4) With the surface of the SiC substrate to be bonded as the ion implantation surface, hydrogen ions are implanted into the SiC substrate to form a pre-stripping buried layer, wherein the specific parameters of the hydrogen ion implantation are: an implantation energy of 130 keV and an implantation dose of 7E16 ions / cm 2 , the tilt angle is 7°, the twist angle is 23°, and the injection temperature is 50°C; then -6Pa, at a temperature of 25 ° C and a pressure of 60 kN, the surface of the SiC layer in the composite substrate away from the SiO2 layer is bonded to the surface to be bonded of the SiC substrate for 2 minutes, and then the bonded body is heat treated at 1100 ° C for 20 minutes in a nitrogen atmosphere, so that the bonded body is broken along the pre-stripped buried layer, and then the heterogeneous composite substrate precursor obtained after the break is annealed and repaired at 1150 ° C for 540 minutes in a nitrogen atmosphere, and then the time is 450 s and the amount of removal is The heterogeneous composite substrate and the remaining SiC substrate are obtained by chemical mechanical polishing.

[0082] The same test method as in Example 1 was used to test, and it was found that the bonding strength of the heterogeneous composite substrate prepared in this example was 1.2 J / m 2 ; Bow value is 7μm, Warp value is 12μm.

[0083] It can be seen from Examples 1-2 that the SiCOI structured heterogeneous composite substrate prepared by the method of the present invention exhibits high bonding strength, high flatness and low warpage, and has excellent quality.

[0084] Example 3

[0085] This embodiment provides a method for manufacturing a heterogeneous composite substrate, comprising the following steps:

[0086] (1) With one side of the Si substrate as the O ion implantation surface, the Si substrate is implanted with O ions to obtain a Si substrate having an O implantation layer; wherein the specific parameters of the O ion implantation are: an implantation energy of 3000 keV, an implantation dose of 8E17ions / cm 2 , the tilt angle is 7°, the twist angle is 23°, and the injection temperature is 650°C; taking the O ion injection surface as a reference, the injection depth of the O ions is 0.6 μm; the thickness of the O injection layer is 0.4 μm; then, in an argon atmosphere, the Si substrate with the O injection layer is annealed and repaired at 1200°C for 300 minutes to transform the O injection layer into a SiO2 layer, thereby obtaining a Si substrate with a SiO2 layer;

[0087] (2) The O ion implantation surface is used as a C ion implantation surface, and C ions are implanted into the Si substrate having the SiO2 layer to form a C implantation layer on the SiO2 layer, thereby obtaining a composite substrate precursor, wherein the composite substrate precursor is composed of a Si layer, a SiO2 layer, a C implantation layer and a Si layer stacked in sequence; wherein the specific parameters for implanting the C ions are: an implantation energy of 150 keV, an implantation dose of 6E17ions / cm 2, the tilt angle is 7°, the twist angle is 23°, and the injection temperature is 700°C; based on the C ion injection surface, the injection depth of the C ions is 0.4 μm; the thickness of the C injection layer is 0.25 μm;

[0088] (3) annealing and repairing the composite substrate precursor at 1200° C. for 300 min in an argon atmosphere, so that the C-injected layer is converted into a SiC layer, thereby obtaining a repaired Si substrate; chemically mechanically polishing the repaired Si substrate for 200 s, thereby removing the Si layer in contact with the SiC layer and exposing the surface of the SiC layer, thereby obtaining a composite substrate, wherein the composite substrate is composed of a Si layer, a SiO2 layer, and a SiC layer stacked in sequence;

[0089] (4) With the surface of the SiC substrate to be bonded as the ion implantation surface, hydrogen ions are implanted into the SiC substrate to form a pre-stripping buried layer, wherein the specific parameters of the hydrogen ion implantation are: an implantation energy of 100 keV and an implantation dose of 6E16 ions / cm 2 , the tilt angle is 7°, the twist angle is 23°, and the injection temperature is 40°C; then -6 Pa absolute vacuum, at a temperature of 26 ° C and a pressure of 50 kN, the surface of the SiC layer in the composite substrate away from the SiO2 layer is bonded to the surface to be bonded of the SiC substrate for 1 min, and then the bonded body is heat treated at 1000 ° C for 30 min in a nitrogen atmosphere, so that the bonded body is broken along the pre-stripped buried layer, and then the heterogeneous composite substrate precursor obtained after the break is annealed and repaired at 1100 ° C for 600 min in a nitrogen atmosphere, and then the time is 300 s and the amount of removal is The heterogeneous composite substrate and the remaining SiC substrate are obtained by chemical mechanical polishing.

[0090] The same test method as in Example 1 was used to test, and it was found that the bonding strength of the heterogeneous composite substrate prepared in this example was 1.18 J / m 2 ; The Bow value is 22μm and the Warp value is 26μm.

[0091] Comparing Example 1 and Example 3, it can be seen that when the O-injection layer and the C-injection layer are transformed successively through two-step annealing repair, a larger thermal budget will be generated due to multiple annealings, resulting in a worse geometric morphology of the final product.

[0092] Example 4

[0093] The difference between this embodiment and embodiment 1 is that the thickness of the C-implanted layer is adjusted to 0.01 μm by adjusting the C ion implantation parameters. The remaining steps and parameters are the same as those in embodiment 1.

[0094] The same test method as in Example 1 was used to test, and it was found that the bonding strength of the heterogeneous composite substrate prepared in this example was 0.8 J / m 2 ; Bow value is 8μm, Warp value is 13μm.

[0095] By comparing Example 1 and Example 4, it can be seen that if the C injection layer is too thin, the bonding strength will be weakened, affecting the subsequent process production.

[0096] Comparative Example 1

[0097] This comparative example provides a method for manufacturing a heterogeneous composite substrate, comprising the following steps:

[0098] (1) With one side of the Si substrate as the O ion implantation surface, O ions are implanted into the Si substrate, wherein the specific parameters of the O ion implantation are: an implantation energy of 300 keV and an implantation dose of 8E17 ions / cm 2 , the tilt angle is 7°, the twist angle is 23°, and the injection temperature is 650°C; the injection depth of the O ions is 0.6 μm based on the O ion injection surface; the thickness of the O injection layer is 0.4 μm, and a composite substrate precursor consisting of a Si layer, an O injection layer and a Si layer stacked in sequence is obtained;

[0099] (2) annealing and repairing the composite substrate precursor at 1200° C. for 300 min in an argon atmosphere, so that the O-injected layer is converted into a SiO2 layer, thereby obtaining a repaired Si substrate; chemically mechanically polishing the repaired Si substrate for 180 s, thereby removing the thinner Si layer and exposing the surface of the SiO2 layer, thereby obtaining a composite substrate, wherein the composite substrate is composed of a Si layer and a SiO2 layer stacked in sequence;

[0100] (3) With the surface of the SiC substrate to be bonded as the ion implantation surface, hydrogen ions are implanted into the SiC substrate to form a pre-stripping buried layer, wherein the specific parameters of the hydrogen ion implantation are: an implantation energy of 100 keV and an implantation dose of 6E16 ions / cm 2 , the tilt angle is 7°, the twist angle is 23°, and the injection temperature is 40°C; then -6 Pa absolute vacuum, at a temperature of 26 ° C and a pressure of 50 kN, the surface of the SiO2 layer in the composite substrate away from the Si layer is bonded to the surface to be bonded of the SiC substrate for 1 min, and then the bonded body is heat treated at 1000 ° C for 30 min in a nitrogen atmosphere to make the bonded body break along the pre-stripped buried layer, and then the heterogeneous composite substrate precursor obtained after the break is annealed and repaired at 1100 ° C for 600 min in a nitrogen atmosphere, and then the time is 300 s and the amount of removal is The heterogeneous composite substrate and the remaining SiC substrate are obtained by chemical mechanical polishing.

[0101] The same test method as in Example 1 was used to test, and it was found that the bonding strength of the heterogeneous composite substrate prepared in this comparative example was 0.8 J / m 2 ; Bow value and Warp value exceed the range.

[0102] Comparison of Example 1 and Comparative Example 1 shows that if the SiO2 layer is directly bonded to the silicon carbide substrate, in the subsequent high-temperature process, due to excessive lattice mismatch and thermal mismatch, serious defects will appear on the bonding interface, resulting in low bonding strength and poor quality of the heterogeneous composite substrate. If an intermediate bonding layer is introduced to improve the lattice mismatch and thermal mismatch problems, new materials will be introduced into the composite substrate, which will cause new problems in the subsequent semiconductor device preparation, which is undesirable.

[0103] Comparative Example 2

[0104] This comparative example provides a method for manufacturing a heterogeneous composite substrate, comprising the following steps:

[0105] (1) Using one side of the Si substrate as the O ion implantation surface, the Si substrate is implanted with O ions, wherein the specific parameters of the O ion implantation are: an implantation energy of 1 to 1000 keV, an implantation dose of 1E16 to 1E18 ions / cm 2 , the tilt angle is 0 to 60°, the twist angle is 0 to 90°, and the injection temperature is 20 to 800°C; the injection depth of the O ions is 0.8 μm based on the O ion injection surface; the thickness of the O injection layer is 0.4 μm, and a composite substrate precursor consisting of a Si layer, an O injection layer and a Si layer stacked in sequence is obtained;

[0106] (2) annealing and repairing the composite substrate precursor at 1000° C. for 200 min in a nitrogen atmosphere, so that the O-injected layer is converted into a SiO2 layer, thereby obtaining a repaired Si substrate; chemically mechanically polishing the repaired Si substrate for 200 s, thereby removing the thinner Si layer to expose the surface of the SiO2 layer, and then depositing a 0.3 μm thick SiC layer on the surface of the SiO2 layer at a temperature of 1350° C. and a pressure of 100 mbar using SiH4 and C3H8 as gas raw materials, thereby obtaining a composite substrate, wherein the composite substrate is composed of a Si layer, a SiO2 layer and a SiC layer stacked in sequence;

[0107] (3) With the surface of the SiC substrate to be bonded as the ion implantation surface, hydrogen ions are implanted into the SiC substrate to form a pre-stripping buried layer, wherein the specific parameters of the hydrogen ion implantation are: an implantation energy of 100 keV and an implantation dose of 6E16 ions / cm 2, the tilt angle is 7°, the twist angle is 23°, and the injection temperature is 40°C; then -6 Pa absolute vacuum, at a temperature of 26 ° C and a pressure of 50 kN, the surface of the SiC layer in the composite substrate away from the SiO2 layer is bonded to the surface to be bonded of the SiC substrate for 1 min, and then the bonded body is heat treated at 1000 ° C for 30 min in a nitrogen atmosphere, so that the bonded body is broken along the pre-stripped buried layer, and then the heterogeneous composite substrate precursor obtained after the break is annealed and repaired at 1100 ° C for 600 min in a nitrogen atmosphere, and then the time is 300 s and the amount of removal is The heterogeneous composite substrate and the remaining SiC substrate are obtained by chemical mechanical polishing.

[0108] The same test method as in Example 1 was used to test, and it was found that the bonding strength of the heterogeneous composite substrate prepared in this comparative example was 0.6 J / m 2 ; Bow value is 13μm, Warp value is 20μm.

[0109] By comparing Example 1 and Comparative Example 2, it can be seen that if the SiC layer is prepared by epitaxial deposition, the quality of the deposited SiC layer is poor, and the bonding force between the SiC layer and the donor SiC substrate is poor. The two may be separated in the subsequent high temperature or CMP process and cannot be used normally.

[0110] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention are within the protection scope and disclosure scope of the present invention.

Claims

1. A method for manufacturing a heterogeneous composite substrate, characterized in that: The production method comprises: (1) performing O ion implantation on a Si substrate to form an O implantation layer, and then performing C ion implantation to form a C implantation layer on the O implantation layer, thereby obtaining a composite substrate precursor; (2) annealing and repairing the composite substrate precursor to transform the O-injected layer into a SiO2 layer and transform the C-injected layer into a SiC layer, and then performing post-processing to obtain a composite substrate; the composite substrate comprises a Si layer, a SiO2 layer and a SiC layer stacked in sequence; (3) Bonding a surface of the SiC layer in the composite substrate away from the SiO2 layer to a surface to be bonded of the SiC substrate to obtain the heterogeneous composite substrate.

2. The method according to claim 1, characterized in that: The specific parameters of the O ion injection include: injection energy of 1 to 1000 keV; injection dose of 1E16 to 1E18 ions / cm 2 ; The tilt angle is 0 to 60°; The torsion angle is 0 to 90°; The injection temperature is 20 to 800°C.

3. The production method according to claim 1 or 2, characterized in that: Taking the O ion implantation surface of the Si substrate as a reference, the implantation depth of the O ions is 0.1 to 1.5 μm; Preferably, the thickness of the O injection layer is 0.1-0.9 μm.

4. The production method according to any one of claims 1 to 3, characterized in that: The specific parameters of the C ion injection include: injection energy of 1 to 1000 keV; injection dose of 1E16 to 1E18 ions / cm 2 ; The tilt angle is 0 to 60°; The torsion angle is 0 to 90°; The injection temperature is 20 to 800°C.

5. The production method according to any one of claims 1 to 4, characterized in that: The O ion implantation surface of the Si substrate and the C ion implantation surface of the Si substrate are the same surface; Preferably, the C ion implantation depth is 0.05 to 1.5 μm based on the C ion implantation surface of the Si substrate; Preferably, the implantation depth of the C ions is less than the implantation depth of the O ions; Preferably, the thickness of the C injection layer is 0.02-0.9 μm.

6. The production method according to any one of claims 1 to 5, characterized in that: The annealing repair temperature is 800-1350°C; Preferably, the annealing repair time is 10 to 500 minutes; Preferably, the annealing repair is performed under an inert atmosphere.

7. The production method according to any one of claims 1 to 6, characterized in that: The post-processing method includes chemical mechanical polishing; Preferably, the chemical mechanical polishing time is 30 to 500 seconds; Preferably, the removal amount of the chemical mechanical polishing is 8. The production method according to any one of claims 1 to 7, characterized in that: In step (3), before bonding, ion implantation is performed on the surface of the SiC substrate to be bonded to form a pre-stripping buried layer; Preferably, the absolute vacuum degree of the bonding is ≤10 -6 Pa; Preferably, the bonding temperature is 20 to 30°C; Preferably, the bonding pressure is 10 to 100 kN; Preferably, after the bonding, the bonded body is heat treated so that the bonded body is broken along the pre-stripping buried layer to obtain the heterogeneous composite substrate and the remaining SiC substrate; Preferably, the temperature of the heat treatment is 800-1200° C.; the time of the heat treatment is 1-60 min; Preferably, the heat treatment is performed under an inert atmosphere.

9. The production method according to any one of claims 1 to 8, characterized in that: The production method specifically comprises the steps of: (I) With one side of the Si substrate as the O ion implantation surface, the Si substrate is implanted with O ions to obtain a Si substrate having an O implantation layer; wherein the specific parameters of the O ion implantation include: an implantation energy of 1 to 1000 keV; an implantation dose of 1E16 to 1E18 ions / cm 2 ; The tilt angle is 0 to 60°; The twist angle is 0 to 90°; The injection temperature is 20 to 800°C; Based on the O ion injection surface, the O ion injection depth is 0.1 to 1.5 μm; The thickness of the O injection layer is 0.1 to 0.9 μm; (II) The O ion implantation surface is used as a C ion implantation surface, and C ions are implanted into the Si substrate having the O implantation layer to form a C implantation layer on the O implantation layer, thereby obtaining a composite substrate precursor, wherein the composite substrate precursor is composed of a Si layer, an O implantation layer, a C implantation layer and a Si layer stacked in sequence; wherein the specific parameters for implanting the C ions include: an implantation energy of 1 to 1000 keV; an implantation dose of 1E16 to 1E18 ions / cm 2 ; The tilt angle is 0 to 60°; The twist angle is 0 to 90°; The injection temperature is 20 to 800°C; The injection depth of the C ions is 0.05 to 1.5 μm based on the C ion injection surface; The injection depth of the C ions is less than the injection depth of the O ions; The thickness of the C injection layer is 0.02 to 0.9 μm; (III) annealing and repairing the composite substrate precursor at 800 to 1350° C. for 10 to 500 min in a nitrogen or argon atmosphere, so that the O injection layer is converted into a SiO2 layer, and the C injection layer is converted into a SiC layer, to obtain a repaired Si substrate; chemically mechanically polishing the repaired Si substrate for 30 to 500 s to remove the Si layer in contact with the SiC layer, to obtain a composite substrate, wherein the composite substrate is composed of a Si layer, a SiO2 layer and a SiC layer stacked in sequence; (IV) Using the surface of the SiC substrate to be bonded as the ion implantation surface, hydrogen ions or helium ions are implanted into the SiC substrate to form a pre-stripping buried layer; then, -6 Pa, at a temperature of 20 to 30 ° C and a pressure of 10 to 100 kN, the surface of the SiC layer in the composite substrate away from the SiO2 layer is bonded to the surface to be bonded of the SiC substrate for 0.5 to 5 min, and then the bonded body is heat-treated at 800 to 1200 ° C for 1 to 60 min in a nitrogen or argon atmosphere, so that the bonded body is broken along the pre-stripped buried layer, and then the heterogeneous composite substrate precursor obtained after the break is annealed and repaired at 800 to 1300 ° C for 10 to 660 min in a nitrogen or argon atmosphere, and then the heterogeneous composite substrate precursor is annealed and repaired for 30 to 500 s and the amount of the pre-stripped buried layer is removed. Chemical mechanical polishing is performed to obtain the heterogeneous composite substrate and the remaining SiC substrate; wherein the specific parameters of the hydrogen ions or helium ions implanted include: an implantation energy of 1 to 1000 keV; an implantation dose of 1E16 to 1E18 ions / cm 2 ; The tilt angle is 0 to 60°; The torsion angle is 0 to 90°; The injection temperature is 20 to 600°C.

10. A heterogeneous composite substrate, characterized in that: The heterogeneous composite substrate is made by the manufacturing method according to any one of claims 1 to 9; Preferably, the heterogeneous composite substrate comprises a Si layer, a SiO2 layer, a first SiC layer and a second SiC layer stacked in sequence, and the first SiC layer and the second SiC layer are bonded to each other; Preferably, the bonding strength between the first SiC layer and the second SiC layer is ≥1.2 J / m 2 .

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