Heterogeneous composite substrate and preparation method and application thereof

Abstract

The invention provides a heterogeneous composite substrate and a preparation method and application thereof. The preparation method comprises the following steps: providing a semi-finished product substrate and a glass substrate, wherein the semi-finished product substrate comprises a silicon substrate layer, a supporting layer, a hydrogenated amorphous silicon layer and a silicon carbide layer which are sequentially arranged from bottom to top; bonding the silicon carbide layer surface of the semi-finished product substrate with the surface of one side of the glass substrate to obtain a bonding body; stripping the bonding body to enable the bonding body to crack along the hydrogenated amorphous silicon layer, and then removing the residual hydrogenated amorphous silicon layer on the surface of the silicon carbide layer to obtain a heterogeneous composite substrate; the heterogeneous composite substrate comprises a glass substrate and a silicon carbide layer which are arranged in a stacked mode. The hydrogenated amorphous silicon layer is introduced as a medium sacrificial layer, so that the stripping temperature during subsequent stripping treatment can be effectively reduced, the damage to the glass substrate is avoided, the structural integrity of the glass substrate is ensured, the problem of thermal mismatch is solved based on the prepared heterogeneous composite substrate, and the silicon carbide layer shows excellent uniformity.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor material processing, and in particular relates to a heterogeneous composite substrate and a preparation method and application thereof. Background Art

[0002] Silicon carbide (SiC), as a third-generation semiconductor material, has outstanding properties such as wide bandgap, high thermal conductivity, low loss in the visible to near-infrared band, wide transparency window (0.37-5.6μm), large second-order / third-order nonlinear coefficients, compatibility with CMOS (complementary metal oxide semiconductor) processes, rich solid-state quantum light sources and excellent mechanical hardness. It shows great potential in high-power electronic devices, high-temperature and high-frequency devices, optoelectronics and optics.

[0003] Although semi-insulating SiC heterojunction substrates (i.e., heterojunction substrates combining semi-insulating SiC with glass substrates) have great potential for future market applications, their preparation still presents numerous challenges. Thermal mismatch must be considered, and the semi-insulating SiC layer within the substrate must maintain high uniformity. Direct ion implantation and exfoliation methods, however, can lead to deformation and fragmentation of the glass substrate during the exfoliation process due to the high exfoliation temperature. Ultimately, the desired heterojunction substrate cannot be obtained.

[0004] Therefore, how to solve the thermal mismatch of the semi-insulating SiC heterojunction substrate and the easy damage of the glass substrate, while making the semi-insulating SiC layer have high uniformity, is a technical problem that needs to be solved urgently. Summary of the Invention

[0005] In response to the shortcomings of the prior art, the present invention aims to provide a heterogeneous composite substrate, its preparation method, and its application. By introducing a low-melting-point, high-absorptivity hydrogenated amorphous silicon layer as a dielectric sacrificial layer, the present invention can effectively reduce the stripping temperature during the subsequent stripping process, avoiding damage to the glass substrate and ensuring the structural integrity of the glass substrate. The resulting heterogeneous composite substrate solves the thermal mismatch problem, and the quality of the silicon carbide layer is almost identical to that of single-crystal silicon carbide, with virtually no deformation, demonstrating excellent uniformity and film quality.

[0006] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

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

[0008] A semi-finished substrate and a glass substrate are provided. The semi-finished substrate includes a supporting substrate, a hydrogenated amorphous silicon layer and a silicon carbide layer which are arranged in sequence from bottom to top.

[0009] The silicon carbide layer of the semi-finished substrate is bonded to one side surface of the glass substrate to obtain a bonded body.

[0010] The bonded body is subjected to a peeling process so that the bonded body is cracked along the hydrogenated amorphous silicon layer, and then the hydrogenated amorphous silicon layer remaining on the surface of the silicon carbide layer is removed to obtain the heterogeneous composite substrate; the heterogeneous composite substrate includes a glass substrate and a silicon carbide layer stacked together.

[0011] The present invention introduces a low-melting-point, high-absorption hydrogenated amorphous silicon layer as a dielectric sacrificial layer, which can effectively reduce the stripping temperature during subsequent stripping treatment, avoid damage to the glass substrate, and ensure the structural integrity of the glass substrate. The heterogeneous composite substrate prepared in this way solves the thermal mismatch problem, and the quality of the silicon carbide layer is almost the same as that of single-crystalline silicon carbide, and it is almost non-deformable, showing excellent uniformity and film quality.

[0012] It should be noted that after the stripping process, in addition to obtaining a heterogeneous composite substrate having a residual hydrogenated amorphous silicon layer on the surface of the silicon carbide layer, a remaining supporting substrate is also obtained, and the supporting substrate can be reused.

[0013] Preferably, the silicon carbide layer is a semi-insulating silicon carbide layer. It should be noted that the semi-insulating silicon carbide layer has a relatively high resistivity, usually greater than 1×10 8 Ω·cm, with excellent optical properties, such as low loss in the visible to near-infrared band, a wide transparent window (0.37-5.6μm), and large second-order / third-order nonlinear coefficients.

[0014] Preferably, the atomic fraction of hydrogen atoms in the hydrogenated amorphous silicon layer is 5-15%, for example, 5%, 8%, 10%, 12% or 15%. It should be noted that the atomic fraction of hydrogen atoms refers to the atomic proportion of hydrogen atoms in the entire hydrogenated amorphous silicon material, usually expressed as a percentage (%).

[0015] In the present invention, the atomic fraction of hydrogen atoms in the hydrogenated amorphous silicon layer is within an appropriate range, which facilitates subsequent laser lift-off.

[0016] Preferably, the thickness of the hydrogenated amorphous silicon layer is 10-100 nm, for example, 10 nm, 20 nm, 50 nm, 60 nm or 80 nm.

[0017] In the present invention, the hydrogenated amorphous silicon layer has a suitable thickness, which is convenient for deposition and laser lift-off at a suitable position.

[0018] Preferably, the bonding method includes a room temperature bonding method or a hydrophilic bonding method.

[0019] Preferably, the parameters of the room temperature bonding method include:

[0020] The bonding temperature is 20-30°C, for example, 20°C, 22°C, 24°C, 26°C, 28°C or 30°C, and the absolute vacuum degree is ≤1×10 -6 Pa, for example, can be 8×10 -7 Pa, 5×10 -7 Pa, 3×10 -7 Pa or 1×10 -7 Pa, etc., and the bonding pressure is 20-80 kN, for example, it can be 20 kN, 30 kN, 40 kN, 50 kN, 60 kN, 70 kN or 80 kN.

[0021] Preferably, the parameters of the hydrophilic bonding method include:

[0022] The activation gas includes oxygen and nitrogen, the power is 50-150W, for example, it can be 50W, 75W, 100W, 125W or 150W, etc., the bonding pressure is 500-8000N, for example, it can be 500N, 1000N, 2000N, 3000N, 4000N, 5000N, 6000N, 7000N or 8000N, etc., and the bonding time is 10-100s, for example, it can be 10s, 30s, 50s, 70s, 90s or 100s, etc.

[0023] In the hydrophilic bonding method of the present invention, the use of activated gas can not only clean the bonding surface to a certain extent, but also make the bonding surface easier to perform bonding operations.

[0024] Preferably, the bonding strength of the bonding interface after bonding is ≥1.4 J / m 2 , for example, it can be 1.4 J / m 2 , 1.6J / m 2 , 1.8J / m 2 , 2J / m 2 , 2.2J / m 2 or 2.4 J / m 2 wait.

[0025] Preferably, the stripping method is a laser stripping method.

[0026] The present invention uses laser stripping to crack the bonded body along the hydrogenated amorphous silicon layer. The temperature during the process is low, and the glass substrate will not be damaged, deformed, or fragmented.

[0027] Preferably, the parameters of the laser lift-off method include:

[0028] The pulse width is 5-30ns, for example, 5s, 10s, 15s, 20s, 25s or 30s, and the energy density is 100-300mJ / cm 2 , for example, it can be 100mJ / cm 2 , 200mJ / cm 2 or 300mJ / cm 2 The scanning speed is 0.5-5 mm / s, for example, it can be 0.5 mm / s, 1 mm / s, 2 mm / s, 3 mm / s, 4 mm / s or 5 mm / s, etc.

[0029] In the present invention, under the above parameter limitations, the laser is easily absorbed by the hydrogenated amorphous silicon layer without causing high temperatures in other layers, which greatly reduces the negative impact of high temperatures on the glass substrate during the stripping process.

[0030] It should be noted that the laser used in the laser lift-off method may be a XeCl excimer laser having a wavelength of 308 nm.

[0031] Preferably, in the laser lift-off method, the laser irradiation target is the hydrogenated amorphous silicon layer.

[0032] Preferably, the method for removing the residual hydrogenated amorphous silicon layer on the surface of the silicon carbide layer includes a polishing method. The present invention does not limit the time and removal amount of the polishing method, as long as the residual silicon oxide layer on the surface of the silicon carbide layer can be removed. For example, the polishing time of the polishing method is 30-300s, such as 30s, 50s, 100s, 200s or 300s, and the removal amount of the polishing method can be, for example, like or wait.

[0033] Preferably, the polishing treatment method includes a chemical mechanical polishing method.

[0034] Preferably, the steps of preparing the semi-finished substrate include:

[0035] A supporting substrate and a silicon carbide substrate are provided. The silicon carbide substrate is a silicon carbide integral structure. A weakened layer is formed inside the silicon carbide integral structure for separating and forming a silicon carbide layer and a silicon carbide residual layer.

[0036] A hydrogenated amorphous silicon layer is prepared on the surface to be bonded of the supporting substrate and / or the surface of the silicon carbide layer, and then the supporting substrate and the silicon carbide substrate are bonded to obtain an intermediate, which includes a supporting substrate, a hydrogenated amorphous silicon layer, a silicon carbide layer, a weakened layer and a silicon carbide residual layer arranged in sequence from bottom to top.

[0037] A splitting process is performed along the weakened layer to obtain the semi-finished substrate.

[0038] It should be noted that after the splitting process, in addition to obtaining a semi-finished substrate, a remaining silicon carbide residual layer is also obtained, which can be reused.

[0039] Preferably, the support substrate and the silicon carbide substrate are bonded, and the bonding strength of the bonding interface after bonding is ≥1.4 J / m 2 , for example, it can be 1.4 J / m 2 , 1.6J / m 2 , 1.8J / m 2 , 2J / m 2 , 2.2J / m 2 or 2.4 J / m 2 wait.

[0040] Preferably, the support substrate includes a silicon oxide substrate or a sapphire substrate.

[0041] Preferably, the silicon oxide substrate includes a silicon base layer and a silicon oxide layer stacked together.

[0042] Preferably, the method for preparing the hydrogenated amorphous silicon layer includes a PECVD method (plasma enhanced chemical vapor deposition method).

[0043] Preferably, the temperature of the splitting treatment is 800-1200°C, for example, 800°C, 900°C, 1000°C, 1100°C or 1200°C.

[0044] Preferably, the fragmentation treatment time is 1-60 min, for example, 1 min, 5 min, 10 min, 20 min, 30 min, 40 min, 50 min or 60 min.

[0045] Preferably, the atmosphere for the splitting process is an inert atmosphere, for example, a nitrogen atmosphere or an argon atmosphere.

[0046] Preferably, after the splitting process, an annealing repair process is also performed.

[0047] In the present invention, the implantation damage is repaired by annealing repair treatment, and deformation can be slowed down, so that the heterogeneous composite substrate can withstand higher temperatures without significant deformation.

[0048] It should be noted that, in the present invention, a polishing process may be performed after the annealing repair process is completed. The polishing process may obtain a smooth surface, which is convenient for bonding the substrate to be processed with the glass substrate.

[0049] Preferably, the temperature range of the annealing repair process is 100-1300°C, for example, it can be 100°C, 300°C, 500°C, 800°C, 900°C, 1000°C, 1100°C, 1200°C or 1300°C, and the time is 10-660min, for example, it can be 10min, 30min, 50min, 100min, 200min, 300min, 400min, 500min, 600min or 660min, etc.

[0050] Preferably, the annealing repair process is a one-step annealing process or a gradient temperature annealing process, for example, 300°C for 1 hour, 500°C for 1 hour, 700°C for 1 hour, 900°C for 1 hour, and 1100°C for 1 hour.

[0051] Preferably, the atmosphere of the annealing repair process is an inert atmosphere, such as a nitrogen atmosphere or an argon atmosphere.

[0052] Preferably, the preparation method comprises the following steps:

[0053] (1) A silicon substrate and a semi-insulating silicon carbide substrate are provided.

[0054] Oxidation is performed on one side surface of the silicon substrate to form a silicon oxide layer to obtain a supporting substrate; ion implantation is performed on one side surface of the semi-insulating silicon carbide substrate to form a weakened layer to obtain a semi-insulating silicon carbide substrate.

[0055] The ion type of the ion implantation includes hydrogen ions, and the parameters of the ion implantation include: an implantation energy of 1-1000kev, for example, 1kev, 10kev, 100kev, 300kev, 500kev, 700kev, 900kev or 1000kev, etc., and an implantation dose of 1×10 16 -1×10 18 Ions / cm 2 , for example, it can be 1×10 16 Ions / cm 2 , 5×10 16 Ions / cm 2 , 1×10 17 Ions / cm 2 , 5×101 7 Ions / cm 2 or 1×10 18 Ions / cm 2etc., the Tilt angle is 0-60°, for example, it can be 0°, 5°, 7°, 10°, 15° or 45°, etc., the Twist angle is 0-90°, for example, it can be 0°, 22°, 23°, 45° or 90°, etc., and the injection temperature is 20-800°C, for example, it can be 20°C, 50°C, 100°C, 200°C, 400°C, 600°C or 800°C, etc.

[0056] (2) preparing a hydrogenated amorphous silicon layer on the surface of the silicon oxide layer and / or the surface of the semi-insulating silicon carbide layer, and then performing a first bonding on the supporting substrate and the semi-insulating silicon carbide substrate, wherein the bonding strength of the bonding interface after bonding is ≥1.4 J / m 2 , obtaining an intermediate; the intermediate includes a silicon base layer, a silicon oxide layer, a hydrogenated amorphous silicon layer, a semi-insulating silicon carbide layer, a weakened layer and a semi-insulating silicon carbide residual layer arranged in sequence from bottom to top.

[0057] The preparation method of the hydrogenated amorphous silicon layer includes a PECVD method, the atomic fraction of hydrogen atoms in the hydrogenated amorphous silicon layer is 5-15%; the first bonding method includes a room temperature bonding method or a hydrophilic bonding method; the parameters of the room temperature bonding method include: a bonding temperature of 20-30°C, an absolute vacuum degree of ≤1×10 -6 Pa, bonding pressure is 20-80kN; the parameters of the hydrophilic bonding method include: activation gas includes oxygen and nitrogen, power is 50-150W, bonding pressure is 500-8000N, and bonding time is 10-100s.

[0058] (3) performing a splitting process along the weakened layer, and then performing an annealing repair process and a polishing process to obtain a semi-finished substrate, wherein the semi-finished substrate includes a silicon base layer, a silicon oxide layer, a hydrogenated amorphous silicon layer, and a semi-insulating silicon carbide layer arranged in sequence from bottom to top.

[0059] The temperature of the splintering treatment is 800-1200°C, the time of the splintering treatment is 1-60 minutes, and the atmosphere of the splintering treatment is an inert atmosphere; the temperature range of the annealing repair process is 100-1300°C, the time is 10-660 minutes, and the atmosphere is an inert atmosphere.

[0060] (4) Providing a glass substrate; performing a second bonding between the semi-insulating silicon carbide layer of the semi-finished substrate and one side surface of the glass substrate, wherein the bonding strength of the bonding interface after bonding is ≥1.4 J / m 2 , and obtain a bonded body.

[0061] The second bonding method includes a room temperature bonding method or a hydrophilic bonding method; the parameters of the room temperature bonding method include: a bonding temperature of 20-30°C, an absolute vacuum degree of ≤1×10 -6Pa, bonding pressure is 20-80kN; the parameters of the hydrophilic bonding method include: activation gas includes oxygen and nitrogen, power is 50-150W, bonding pressure is 500-8000N, and bonding time is 10-100s.

[0062] (5) Laser stripping is performed on the bond body so that the bond body is cracked along the hydrogenated amorphous silicon layer, and then the residual hydrogenated amorphous silicon layer on the surface of the semi-insulating silicon carbide layer is removed by polishing to obtain the heterogeneous composite substrate; the heterogeneous composite substrate includes a glass substrate and a semi-insulating silicon carbide layer stacked together.

[0063] The parameters of the laser lift-off method include: pulse width of 5-30ns, energy density of 100-300mJ / cm 2 , the scanning speed is 0.5-5mm / s.

[0064] In a second aspect, the present invention provides a heterogeneous composite substrate, which is prepared by the preparation method described in the first aspect.

[0065] In a third aspect, the present invention provides an application of the heterogeneous composite substrate as described in the second aspect, wherein the heterogeneous composite substrate is used for preparing a semiconductor device.

[0066] The numerical range described in the present invention includes not only the point values ​​listed above, but also 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.

[0067] Compared with the prior art, the present invention has the following beneficial effects:

[0068] (1) The present invention introduces a low-melting-point, high-absorption hydrogenated amorphous silicon layer as a dielectric sacrificial layer, which can effectively reduce the stripping temperature during subsequent stripping treatment, avoid damage to the glass substrate, and ensure the structural integrity of the glass substrate. The heterogeneous composite substrate prepared based on this solves the thermal mismatch problem, and the quality of the silicon carbide layer is almost the same as that of single-crystal silicon carbide, and it is almost deformable, showing excellent uniformity and film quality.

[0069] (2) The preparation method provided by the present invention has simple process and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] Figure 1 This is a schematic flow chart of the preparation method provided in Example 1 of the present invention.

[0071] Among them, 10-silicon substrate; 11-silicon oxide layer; 12-support substrate; 20-semi-insulating silicon carbide substrate; 21-weakened layer; 22-semi-insulating silicon carbide substrate; 23-semi-insulating silicon carbide layer; 24-semi-insulating silicon carbide residual layer; 30-hydrogenated amorphous silicon layer; 40-semi-finished product substrate; 50-glass substrate; 60-heterogeneous composite substrate. DETAILED DESCRIPTION

[0072] The technical solution of the present invention is further described below by way of specific embodiments. It should be understood by those skilled in the art that the embodiments are merely to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0073] Example 1

[0074] This embodiment provides a method for preparing a heterogeneous composite substrate, the flow diagram of which is shown in FIG. Figure 1 As shown, the preparation method comprises the following steps:

[0075] (1) A silicon substrate 10 and a semi-insulating silicon carbide substrate 20 are provided.

[0076] Oxidation is performed on one side surface of the silicon substrate 10 to form a silicon oxide layer 11, thereby obtaining a supporting substrate 12. Ion implantation is performed on one side surface of the semi-insulating silicon carbide substrate 20 to form a weakened layer 21, thereby obtaining a semi-insulating silicon carbide substrate 22. The semi-insulating silicon carbide substrate 22 includes a semi-insulating silicon carbide layer 23, a weakened layer 21, and a semi-insulating silicon carbide residual layer 24, which are sequentially arranged from bottom to top.

[0077] The ion type of ion implantation is hydrogen ion, and the parameters of ion implantation include: implantation energy of 100keV, implantation dose of 6×10 16 Ions / cm 2 , the Tilt angle is 7°, the Twist angle is 23°, and the injection temperature is 60℃.

[0078] (2) A hydrogenated amorphous silicon layer 30 with a thickness of 50 nm is prepared on the surface of the semi-insulating silicon carbide layer 23, and then the supporting substrate 12 and the semi-insulating silicon carbide substrate 22 are first bonded. The bonding strength of the bonding interface after bonding is ≥1.4 J / m 2 , obtaining an intermediate; the intermediate comprises a silicon base layer, a silicon oxide layer 11, a hydrogenated amorphous silicon layer 30, a semi-insulating silicon carbide layer 23, a weakened layer 21 and a semi-insulating silicon carbide residual layer 24 arranged in order from bottom to top.

[0079] The hydrogenated amorphous silicon layer 30 is prepared by PECVD, and the atomic fraction of hydrogen atoms in the hydrogenated amorphous silicon layer 30 is 10%. The first bonding method is a room temperature bonding method, and the parameters of the room temperature bonding method include: a bonding temperature of 25°C, an absolute vacuum of 1×10 -7Pa, and the bonding pressure is 50 kN.

[0080] (3) A splitting process is performed along the weakened layer 21, and then an annealing repair process and chemical mechanical polishing are performed to obtain a semi-finished substrate 40. The semi-finished substrate 40 includes a silicon base layer, a silicon oxide layer 11, a hydrogenated amorphous silicon layer 30 and a semi-insulating silicon carbide layer 23 arranged in sequence from bottom to top.

[0081] The temperature of the splitting treatment is 800°C, the time of the splitting treatment is 60 minutes, and the atmosphere of the splitting treatment is a nitrogen atmosphere; the annealing repair process is a one-step annealing process, the temperature is 1100°C, the time is 60 minutes, and the atmosphere is an argon atmosphere; the processing time of the chemical mechanical polishing is 100 seconds, and the removal amount of the semi-insulating silicon carbide layer 23 on the surface of the hydrogenated amorphous silicon layer 30 is

[0082] (4) Providing a glass substrate 50; performing a second bonding between the semi-insulating silicon carbide layer 23 of the semi-finished substrate 40 and one side surface of the glass substrate 50, wherein the bonding strength of the bonding interface after bonding is ≥1.4 J / m 2 , and obtain a bonded body.

[0083] The second bonding method is a hydrophilic bonding method, and the parameters of the hydrophilic bonding method include: activation gas including oxygen and nitrogen, power of 100 W, bonding pressure of 1000 N, and bonding time of 60 s.

[0084] (5) Laser stripping is performed on the bonded body. The laser irradiation target is the hydrogenated amorphous silicon layer 30, so that the bonded body is cracked along the hydrogenated amorphous silicon layer 30. Then, chemical mechanical polishing is used to remove the hydrogenated amorphous silicon layer 30 remaining on the surface of the semi-insulating silicon carbide layer 23 to obtain a heterogeneous composite substrate 60; the heterogeneous composite substrate 60 includes a stacked glass substrate 50 and a semi-insulating silicon carbide layer 23.

[0085] The parameters of the laser lift-off method include: the laser is a XeCl excimer laser with a wavelength of 308 nm, a pulse width of 25 ns, and an energy density of 120 mJ / cm 2 , the scanning speed is 1mm / s; the processing time of chemical mechanical polishing is 80s, and the removal amount is

[0086] Example 2

[0087] This embodiment provides a method for preparing a heterogeneous composite substrate, the flow diagram of which is shown in FIG. Figure 1 As shown, the preparation method comprises the following steps:

[0088] (1) Provide a sapphire substrate and a semi-insulating silicon carbide substrate.

[0089] Ion implantation is performed on one side surface of a semi-insulating silicon carbide substrate to form a weakened layer, thereby obtaining a semi-insulating silicon carbide substrate. The semi-insulating silicon carbide substrate includes a semi-insulating silicon carbide layer, a weakened layer, and a semi-insulating silicon carbide residual layer arranged in sequence from bottom to top.

[0090] The ion type of ion implantation is hydrogen ion, and the parameters of ion implantation include: implantation energy of 200keV, implantation dose of 1×10 17 Ions / cm 2 , the Tilt angle is 7°, the Twist angle is 23°, and the injection temperature is 80°C.

[0091] (2) A hydrogenated amorphous silicon layer with a thickness of 80 nm is prepared on the surface of the sapphire substrate, and then the sapphire substrate and the semi-insulating silicon carbide substrate are first bonded. The bonding strength of the bonding interface after bonding is ≥1.4 J / m 2 , obtaining an intermediate; the intermediate includes a sapphire substrate, a hydrogenated amorphous silicon layer, a semi-insulating silicon carbide layer, a weakened layer and a semi-insulating silicon carbide residual layer arranged in sequence from bottom to top.

[0092] The hydrogenated amorphous silicon layer is prepared by PECVD, and the atomic fraction of hydrogen atoms in the hydrogenated amorphous silicon layer is 15%. The first bonding method is a room temperature bonding method, and the parameters of the room temperature bonding method include: a bonding temperature of 25°C, an absolute vacuum of 1×10 -7 Pa, and the bonding pressure is 30kN.

[0093] (3) performing a splitting process along the weakened layer, and then performing an annealing repair process and chemical mechanical polishing to obtain a semi-finished substrate, which includes a sapphire substrate, a hydrogenated amorphous silicon layer, and a semi-insulating silicon carbide layer arranged in sequence from bottom to top.

[0094] The temperature of the cracking treatment is 1100℃, the time of the cracking treatment is 30min, and the atmosphere of the cracking treatment is nitrogen atmosphere; the annealing repair process is a one-step annealing process, the temperature is 1300℃, the time is 60min, and the atmosphere is argon atmosphere; the processing time of chemical mechanical polishing is 100s, and the removal amount of the semi-insulating silicon carbide layer on the surface of the hydrogenated amorphous silicon layer is

[0095] (4) Providing a glass substrate; performing a second bonding between the semi-insulating silicon carbide layer of the semi-finished substrate and one side surface of the glass substrate, wherein the bonding strength of the bonding interface after bonding is ≥1.4 J / m 2 , and obtain a bonded body.

[0096] The second bonding method is a hydrophilic bonding method, and the parameters of the hydrophilic bonding method include: activation gas includes oxygen and nitrogen, power is 150W, bonding pressure is 5000N, and bonding time is 100s.

[0097] (5) Laser stripping is performed on the bonded body, where the laser irradiates the hydrogenated amorphous silicon layer, causing the bonded body to crack along the hydrogenated amorphous silicon layer. Then, a chemical mechanical polishing method is used to remove the residual hydrogenated amorphous silicon layer on the surface of the semi-insulating silicon carbide layer to obtain a heterogeneous composite substrate; the heterogeneous composite substrate includes a stacked glass substrate and a semi-insulating silicon carbide layer.

[0098] The parameters of the laser lift-off method include: the laser is a XeCl excimer laser with a wavelength of 308 nm, a pulse width of 20 ns, and an energy density of 200 mJ / cm 2 , the scanning speed is 2mm / s; the processing time of chemical mechanical polishing is 80s, and the removal amount is

[0099] Example 3

[0100] This embodiment provides a method for preparing a heterogeneous composite substrate, the flow diagram of which is shown in FIG. Figure 1 As shown, the preparation method comprises the following steps:

[0101] (1) A silicon substrate and a semi-insulating silicon carbide substrate are provided.

[0102] Oxidation is performed on one side surface of a silicon substrate to form a silicon oxide layer to obtain a supporting substrate; ion implantation is performed on one side surface of a semi-insulating silicon carbide substrate to form a weakened layer to obtain a semi-insulating silicon carbide substrate, which includes a semi-insulating silicon carbide layer, a weakened layer and a semi-insulating silicon carbide residual layer arranged in sequence from bottom to top.

[0103] The ion type of ion implantation is hydrogen ion, and the parameters of ion implantation include: implantation energy of 60keV, implantation dose of 6×10 16 Ions / cm 2 , the Tilt angle is 7°, the Twist angle is 23°, and the injection temperature is 60℃.

[0104] (2) A hydrogenated amorphous silicon layer with a thickness of 20 nm is prepared on the surface of the semi-insulating silicon carbide layer, and then the supporting substrate and the semi-insulating silicon carbide substrate are first bonded. The bonding strength of the bonding interface after bonding is ≥1.4 J / m 2 , obtaining an intermediate; the intermediate includes a silicon base layer, a silicon oxide layer, a hydrogenated amorphous silicon layer, a semi-insulating silicon carbide layer, a weakened layer and a semi-insulating silicon carbide residual layer arranged in sequence from bottom to top.

[0105] The hydrogenated amorphous silicon layer is prepared by PECVD, and the atomic fraction of hydrogen atoms in the hydrogenated amorphous silicon layer is 5%. The first bonding method is a room temperature bonding method, and the parameters of the room temperature bonding method include: a bonding temperature of 25°C, an absolute vacuum of 1×10 -7Pa, and the bonding pressure is 70kN.

[0106] (3) performing a splitting process along the weakened layer, and then performing an annealing repair process and chemical mechanical polishing to obtain a semi-finished substrate, which includes a silicon base layer, a silicon oxide layer, a hydrogenated amorphous silicon layer, and a semi-insulating silicon carbide layer arranged in sequence from bottom to top.

[0107] The temperature of the cracking treatment is 900℃, the time of the cracking treatment is 60min, and the atmosphere of the cracking treatment is a nitrogen atmosphere; the annealing repair process is a one-step annealing process, the temperature is 1000℃, the time is 120min, and the atmosphere is an argon atmosphere; the processing time of the chemical mechanical polishing is 100s, and the removal amount of the semi-insulating silicon carbide layer on the surface of the hydrogenated amorphous silicon layer is

[0108] (4) Providing a glass substrate; performing a second bonding between the semi-insulating silicon carbide layer of the semi-finished substrate and one side surface of the glass substrate, wherein the bonding strength of the bonding interface after bonding is ≥1.4 J / m 2 , and obtain a bonded body.

[0109] The second bonding method is a hydrophilic bonding method, and the parameters of the hydrophilic bonding method include: activation gas includes oxygen and nitrogen, power is 50W, bonding pressure is 500N, and bonding time is 45s.

[0110] (5) Laser stripping is performed on the bonded body, where the laser irradiates the hydrogenated amorphous silicon layer, causing the bonded body to crack along the hydrogenated amorphous silicon layer. Then, a chemical mechanical polishing method is used to remove the residual hydrogenated amorphous silicon layer on the surface of the semi-insulating silicon carbide layer to obtain a heterogeneous composite substrate; the heterogeneous composite substrate includes a stacked glass substrate and a semi-insulating silicon carbide layer.

[0111] The parameters of the laser lift-off method include: the laser is a XeCl excimer laser with a wavelength of 308 nm, a pulse width of 25 ns, and an energy density of 150 mJ / cm 2 , the scanning speed is 0.8mm / s; the processing time of chemical mechanical polishing is 80s, and the removal amount is

[0112] Example 4

[0113] The difference between this embodiment and embodiment 1 is that the atomic fraction of hydrogen atoms in the hydrogenated amorphous silicon layer is 3%.

[0114] The rest of the preparation methods and parameters remained the same as in Example 1.

[0115] Example 5

[0116] The difference between this embodiment and embodiment 1 is that the atomic fraction of hydrogen atoms in the hydrogenated amorphous silicon layer is 20%.

[0117] The rest of the preparation methods and parameters remained the same as in Example 1.

[0118] Example 6

[0119] The difference between this embodiment and embodiment 1 is that the thickness of the hydrogenated amorphous silicon layer in step (2) is 5 nm.

[0120] The rest of the preparation methods and parameters remained the same as in Example 1.

[0121] Example 7

[0122] The difference between this embodiment and embodiment 1 is that the thickness of the hydrogenated amorphous silicon layer in step (2) is 120 nm.

[0123] The rest of the preparation methods and parameters remained the same as in Example 1.

[0124] Example 8

[0125] The difference between this embodiment and embodiment 1 is that the laser stripping method in step (5) is replaced by thermal stripping treatment, that is, the stripping treatment is performed at 500° C. for 60 minutes in a nitrogen atmosphere.

[0126] The rest of the preparation methods and parameters remained the same as in Example 1.

[0127] Example 9

[0128] The difference between this embodiment and embodiment 1 is that the energy density of the laser lift-off method in step (5) is 80 mJ / cm 2 .

[0129] The rest of the preparation methods and parameters remained the same as in Example 1.

[0130] Example 10

[0131] The difference between this embodiment and embodiment 1 is that the energy density of the laser lift-off method in step (5) is 330 mJ / cm 2 .

[0132] The rest of the preparation methods and parameters remained the same as in Example 1.

[0133] Comparative Example 1

[0134] The difference between this comparative example and Example 1 is that no hydrogenated amorphous silicon layer is prepared in step (2).

[0135] The rest of the preparation methods and parameters remained the same as in Example 1.

[0136] Performance Testing

[0137] The glass substrate fragmentation situation of the heterogeneous composite substrates prepared in the above embodiments and comparative examples was counted, and the refractive index and extinction coefficient of the heterogeneous composite substrates were tested using a gyroscopic instrument.

[0138] The statistical and test results are shown in Table 1.

[0139] Table 1

[0140]

[0141]

[0142] analyze:

[0143] As can be seen from Table 1, the present invention introduces a low-melting-point, high-absorptivity hydrogenated amorphous silicon layer as a dielectric sacrificial layer, which can effectively reduce the stripping temperature during the subsequent stripping process, avoid damage to the glass substrate, and ensure the structural integrity of the glass substrate. The heterogeneous composite substrate prepared in this way solves the thermal mismatch problem, and the quality of the silicon carbide layer is almost the same as that of single-crystalline silicon carbide, and it is almost invisible, showing excellent uniformity and film quality. It is expected to promote the widespread application of heterogeneous composite substrates in fields such as Metalens.

[0144] From the comparison between Example 1 and Examples 4-5, it can be seen that if the atomic fraction of hydrogen atoms in the hydrogenated amorphous silicon layer is too small, laser lift-off cannot be performed; if the atomic fraction of hydrogen atoms in the hydrogenated amorphous silicon layer is too large, it will cause waste of cost and time and poor performance.

[0145] From the comparison between Example 1 and Examples 6-7, it can be seen that if the thickness of the hydrogenated amorphous silicon layer is too small, laser lift-off cannot be performed; if the thickness of the hydrogenated amorphous silicon layer is too large, it will cause waste of cost and time and poor performance.

[0146] From the comparison between Example 1 and Example 8, it can be seen that if the laser stripping method is replaced by thermal stripping, the thermal stripping method cannot be used to achieve the stripping effect because there is no implanted weakening layer.

[0147] From the comparison between Example 1 and Examples 9-10, it can be seen that if the energy density in the parameters of the laser lift-off method is too low, lift-off cannot be performed; if the energy density in the parameters of the laser lift-off method is too high, lift-off damage will be caused and the performance will be poor.

[0148] From the comparison between Example 1 and Comparative Example 1, it can be seen that if a hydrogenated amorphous silicon layer is not prepared as a dielectric sacrificial layer, stripping cannot be achieved, and forced stripping will cause defocus damage to the functional layer, and the performance cannot meet the requirements.

[0149] It should be noted that while the present invention illustrates the process method through the above-described embodiments, the present invention is not limited to the above-described process steps, and does not necessarily rely on the above-described process steps for implementation. Those skilled in the art will appreciate that any improvements to the present invention, equivalent replacements for the raw materials used, additions of auxiliary components, and selection of specific methods, etc., fall within the scope of protection and disclosure of the present invention.

Claims

1. A method for preparing a heterogeneous composite substrate, characterized in that: The preparation method comprises the following steps: Providing a semi-finished substrate and a glass substrate, wherein the semi-finished substrate includes a supporting substrate, a hydrogenated amorphous silicon layer, and a silicon carbide layer arranged in sequence from bottom to top; bonding the silicon carbide layer of the semi-finished substrate to one side surface of the glass substrate to obtain a bonded body; The bonded body is subjected to a peeling process so that the bonded body is cracked along the hydrogenated amorphous silicon layer, and then the hydrogenated amorphous silicon layer remaining on the surface of the silicon carbide layer is removed to obtain the heterogeneous composite substrate; the heterogeneous composite substrate includes a glass substrate and a silicon carbide layer stacked together.

2. The preparation method according to claim 1, characterized in that In the hydrogenated amorphous silicon layer, the atomic fraction of hydrogen atoms is 5-15%; Preferably, the thickness of the hydrogenated amorphous silicon layer is 10-100 nm.

3. The preparation method according to claim 1 or 2, characterized in that The bonding method includes a room temperature bonding method or a hydrophilic bonding method; Preferably, the parameters of the room temperature bonding method include: The bonding temperature is 20-30℃ and the absolute vacuum degree is ≤1×10 -6 Pa, bonding pressure is 20-80kN; Preferably, the parameters of the hydrophilic bonding method include: The activation gas includes oxygen and nitrogen, the power is 50-150W, the bonding pressure is 500-8000N, and the bonding time is 10-100s.

4. The preparation method according to any one of claims 1 to 3, characterized in that The stripping method is laser stripping; Preferably, the parameters of the laser lift-off method include: Pulse width is 5-30ns, energy density is 100-300mJ / cm 2 , the scanning speed is 0.5-5mm / s.

5. The preparation method according to any one of claims 1 to 4, characterized in that The method for removing the residual hydrogenated amorphous silicon layer on the surface of the silicon carbide layer includes a polishing method; Preferably, the polishing treatment method includes a chemical mechanical polishing method.

6. The preparation method according to any one of claims 1 to 5, characterized in that The steps of preparing the semi-finished substrate include: Providing a support substrate and a silicon carbide substrate, wherein the silicon carbide substrate is a silicon carbide integral structure, and a weakened layer is formed inside the silicon carbide integral structure for separating and forming a silicon carbide layer and a silicon carbide residual layer; preparing a hydrogenated amorphous silicon layer on the surface to be bonded of the support substrate and / or the surface of the silicon carbide layer, and then bonding the support substrate and the silicon carbide substrate to obtain an intermediate, wherein the intermediate comprises the support substrate, the hydrogenated amorphous silicon layer, the silicon carbide layer, the weakened layer, and the silicon carbide residual layer arranged in sequence from bottom to top; Performing a splitting process along the weakened layer to obtain the semi-finished substrate; Preferably, the support substrate includes a silicon oxide substrate or a sapphire substrate.

7. The preparation method according to claim 6, characterized in that The preparation method of the hydrogenated amorphous silicon layer includes a PECVD method; Preferably, the temperature of the splitting treatment is 800-1200°C; Preferably, the time for the splitting treatment is 1-60 min; Preferably, the atmosphere for the splitting treatment is an inert atmosphere; Preferably, after the splitting process, an annealing repair process is also performed; Preferably, the temperature range of the annealing repair process is 100-1300°C and the time is 10-660min; Preferably, the annealing repair process is a one-step annealing process or a gradient temperature rising annealing process.

8. The preparation method according to any one of claims 1 to 7, characterized in that The preparation method comprises the following steps: (1) Providing a silicon substrate and a semi-insulating silicon carbide substrate; performing oxidation on one side surface of the silicon substrate to form a silicon oxide layer to obtain a support substrate; performing ion implantation on one side surface of the semi-insulating silicon carbide substrate to form a weakened layer to obtain a semi-insulating silicon carbide substrate; The ion types of ion implantation include hydrogen ions, and the parameters of ion implantation include: implantation energy of 1-1000kev, implantation dose of 1×10 16 -1×10 18 Ions / cm 2 , Tilt angle is 0-60°, Twist angle is 0-90°, injection temperature is 20-800℃; (2) preparing a hydrogenated amorphous silicon layer on the surface of the silicon oxide layer and / or the surface of the semi-insulating silicon carbide layer, and then performing a first bonding on the supporting substrate and the semi-insulating silicon carbide substrate, wherein the bonding strength of the bonding interface after bonding is ≥1.4 J / m 2 , obtaining an intermediate; the intermediate comprising a silicon base layer, a silicon oxide layer, a hydrogenated amorphous silicon layer, a semi-insulating silicon carbide layer, a weakened layer and a semi-insulating silicon carbide residual layer arranged in sequence from bottom to top; The preparation method of the hydrogenated amorphous silicon layer includes a PECVD method, the atomic fraction of hydrogen atoms in the hydrogenated amorphous silicon layer is 5-15%; the first bonding method includes a room temperature bonding method or a hydrophilic bonding method; the parameters of the room temperature bonding method include: a bonding temperature of 20-30°C, an absolute vacuum degree of ≤1×10 -6 Pa, bonding pressure is 20-80kN; the parameters of the hydrophilic bonding method include: activation gas including oxygen and nitrogen, power is 50-150W, bonding pressure is 500-8000N, bonding time is 10-100s; (3) performing a splitting process along the weakened layer, and then performing an annealing repair process and a polishing process to obtain a semi-finished substrate, wherein the semi-finished substrate includes a silicon base layer, a silicon oxide layer, a hydrogenated amorphous silicon layer, and a semi-insulating silicon carbide layer arranged in sequence from bottom to top; The temperature of the splintering process is 800-1200°C, the time of the splintering process is 1-60 minutes, and the atmosphere of the splintering process is an inert atmosphere; the temperature range of the annealing repair process is 100-1300°C, the time is 10-660 minutes, and the atmosphere is an inert atmosphere; (4) Providing a glass substrate; performing a second bonding between the semi-insulating silicon carbide layer of the semi-finished substrate and one side surface of the glass substrate, wherein the bonding strength of the bonding interface after bonding is ≥1.4 J / m 2 , to obtain a bonded body; The second bonding method includes a room temperature bonding method or a hydrophilic bonding method; the parameters of the room temperature bonding method include: a bonding temperature of 20-30°C, an absolute vacuum degree of ≤1×10 -6 Pa, bonding pressure is 20-80kN; the parameters of the hydrophilic bonding method include: activation gas including oxygen and nitrogen, power is 50-150W, bonding pressure is 500-8000N, bonding time is 10-100s; (5) performing laser lift-off on the bond body so that the bond body is cracked along the hydrogenated amorphous silicon layer, and then removing the hydrogenated amorphous silicon layer remaining on the surface of the semi-insulating silicon carbide layer by polishing to obtain the heterogeneous composite substrate; the heterogeneous composite substrate includes a glass substrate and a semi-insulating silicon carbide layer stacked together; The parameters of the laser lift-off method include: pulse width of 5-30ns, energy density of 100-300mJ / cm 2 , the scanning speed is 0.5-5mm / s.

9. A heterogeneous composite substrate, characterized in that: The heterogeneous composite substrate is prepared by the preparation method according to any one of claims 1 to 8.

10. An application of the heterogeneous composite substrate according to claim 9, characterized in that: The heterogeneous composite substrate is used for preparing semiconductor devices.

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