CN113871289A - Silicon carbide-based AlScN template for high-frequency high-performance SAW device and preparation method thereof - Google Patents

Silicon carbide-based AlScN template for high-frequency high-performance SAW device and preparation method thereof Download PDF

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CN113871289A
CN113871289A CN202110971256.7A CN202110971256A CN113871289A CN 113871289 A CN113871289 A CN 113871289A CN 202110971256 A CN202110971256 A CN 202110971256A CN 113871289 A CN113871289 A CN 113871289A
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layer
silicon carbide
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吴亮
付丹扬
王琦琨
龚建超
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Aoti Photoelectric Technology Hangzhou Co ltd
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Abstract

The invention discloses a silicon carbide-based AlScN template for a high-frequency high-performance SAW device, which is of a multilayer structure, takes single crystal silicon carbide as a substrate, and sequentially grows SiO on a polished surface of the silicon carbide2The device comprises a layer, a metal passivation layer, an AlN seed layer, a low-concentration Sc-doped AlScN layer and a high-concentration Sc-doped AlScN layer. The preparation method can be used for preparing the AlScN film with high crystallization quality, high phase velocity, low surface roughness, high temperature stability and high Sc concentration. The silicon carbide substrate provides a higher phase velocity; SiO22The layer makes up the defect of poor temperature stability of the AlScN film with high Sc concentration; the lattice mismatch between the AlN seed layer and the AlScN is small, so that the crystallization quality is improved; the low Sc concentration AlScN layer avoids the Sc element from being separated out in advance and reduces lattice mismatch; the high Sc AlScN layer provides goodPiezoelectric properties. The multilayer structure can be better applied to devices based on bulk acoustic waves and surface acoustic waves.

Description

Silicon carbide-based AlScN template for high-frequency high-performance SAW device and preparation method thereof
Technical Field
The invention relates to the technical field of semiconductor material preparation, in particular to an aluminum scandium nitrogen template structure and a preparation method thereof.
Background
With the development of 5G communication technology, the number of newly added 5G frequency bands and original frequency bands is increased, and the deep application of MIMO and CA technologies is increasing, the demand for filters is increasing, and the preparation requirements for radio frequency front ends are also increasing, so that a material with higher piezoelectric performance is required to prepare the filter device SAW/BAW.
The key to the preparation of high performance rf filters lies in the characteristics of the piezoelectric material of the filter substrate and its crystalline quality. Compared with the traditional piezoelectric materials such as ZnO, PZT, LT/LN and the like, the AlN thin film material is one of the ideal piezoelectric materials of the 5G high-performance FBAR/BAW radio frequency filter due to the excellent physical properties such as high resistivity, high thermal conductivity, high stability, high sound wave transmission rate and the like, and is well applied in the industry. For example, the AlN thin film material with a certain preferred orientation has higher sound wave speed (the longitudinal wave speed can reach 11000m/s, and the transverse wave speed is about 6000 m/s), so that the AlN thin film is currently used as a preferred material for preparing GHz high-frequency resonance devices, filter devices and the like. However, although the performance advantage is obvious compared with the traditional piezoelectric materials such as ZnO, PZT, LT/LN and the like, the AlN thin film has the inherent defect that the piezoelectric coefficient of the AlN thin film growing along the c-axis direction is small (d 33= 5-6 pm/V), so that the application of SAW device performance (particularly in a high-frequency band) based on the AlN thin film is subjected to a bottleneck. To solve the bottleneck of AlN thin film material while maintaining other excellent characteristics, an effective method is to dope it to improve its piezoelectric performance. At present, the piezoelectric performance of the material is effectively improved by doping high-content Sc element, so that the electromechanical coupling coefficient of the filter device is improved. However, since the mixing entropy of the ternary nitride alloy is positive due to the high Sc concentration doping, the thin film is in a metastable state, resulting in a tendency of phase decomposition of the material itself. Therefore, the preparation conditions of the high Sc-doped high-quality AlScN film are extremely sensitive, and the method becomes an important difficult problem for restricting the large-scale manufacturing of the AlScN film material and the downstream large-scale industrial application thereof. After high-concentration Sc element (30 at%) is doped, the phase velocity of the material can be rapidly reduced, so that the frequency of a filter device is reduced, abnormal nucleation is easily generated on the surface of the film, the crystallization quality is rapidly reduced, the surface roughness is seriously deteriorated, the temperature stability is reduced, and the SAW/BAW device with high frequency and high performance is difficult to prepare.
Disclosure of Invention
Based on the technical problems existing in the Sc-doped AlN template, the invention aims to provide a multilayer structure, an AlScN template structure taking silicon carbide as a substrate and a preparation method thereof, so as to solve the problems of rapid reduction of material phase speed, abnormal nucleation, large surface roughness, low temperature stability and the like after AlN is doped with high Sc concentration.
In order to achieve the above object, the present invention provides the following technical solutions.
The invention provides a silicon carbide-based AlScN template for a high-frequency high-performance SAW device, which is of a multilayer structure, takes silicon carbide as a substrate, and sequentially grows SiO on the polished surface of the silicon carbide2The device comprises a layer, a metal passivation layer, an AlN seed layer, a low-concentration Sc-doped AlScN layer and a high-concentration Sc-doped AlScN layer. Wherein, SiO2The thickness of the layer film is 10-1000nm, and the thickness of the metal passivation layer film is 5-1000 nm; the thickness of the AlN seed layer is 10-5000 nm; the thickness of the low-concentration Sc-doped AlScN layer is 10-5000nm, and the chemical formula is Al1-xScxN, wherein x is less than or equal to 0.3; the thickness of the high-concentration Sc-doped AlScN layer is 10-5000nm, and the chemical formula is Al1-yScyN, wherein y is more than or equal to 0.3 and less than or equal to 0.6.
Furthermore, the frequency temperature coefficient of the silicon carbide-based AlScN template is lower than-14.73 ppm/K, and the phase velocity reaches more than 5500 m/s.
The invention also provides a method for preparing the silicon carbide-based AlScN template, which comprises the following steps:
1) preparing a silicon carbide substrate; the silicon carbide substrate adopts a single-side polished single wafer, and the roughness is less than 0.3 nm. The use of silicon carbide as the substrate material provides a higher phase velocity.
2) Pretreating the surface of the silicon carbide substrate: removing surface oxides and pollutants by adopting an ion bombardment method;
3) carbonisation after pretreatmentPreparation of SiO on the surface of a silicon substrate2A layer; SiO22The stability of the layer temperature is good, the temperature stability and the shape of the silicon carbide-based AlScN template can be enhanced, and the temperature frequency coefficient is reduced.
4) In SiO2Preparing a metal buffer layer on the layer; the metal buffer layer can effectively passivate SiO2And the thin film is used for effectively preventing amorphous SiNx from being formed with SiO2 when an AlN seed layer is grown later. The metal buffer layer may be a metal Al layer or a metal tungsten layer.
5) Preparing an AlN seed layer on the metal buffer layer; the AlN seed layer can make up for AlScN phase speed loss, has smaller lattice mismatch with AlScN, improves the crystallization quality of the AlScN layer, reduces abnormal nucleation, reduces surface roughness, improves performances such as piezoelectricity and the like.
6) Preparing Al with low Sc concentration on an AlN seed layer1-xScxN layers, wherein x is less than or equal to 0.3; compared with the method that the AlScN layer with the high Sc concentration is directly formed on the seed layer, the AlScN layer with the low Sc concentration is grown on the AlN seed layer, so that the Sc element can be prevented from being separated out in advance, the barrier difference of the valence band between the last barrier layer and the barrier difference is reduced, namely the lattice mismatch between the last barrier layer and the barrier layer is reduced, the introduction of large strain and a polarization field is avoided, the barrier peak formed by the valence band of the electron blocking layer is reduced, and the obstruction of hole injection is reduced.
7) Al at the low Sc concentration1-xScxPreparation of high Sc concentration Al on N layer1-yScyAnd y is more than or equal to 0.3 and less than or equal to 0.6. The piezoelectric property of the silicon carbide-based AlScN template is improved.
Further, the AlN seed layer is grown in the step 5), and an MOCVD method or a magnetron sputtering method is adopted.
Further, the above step 6), 7) preparing Al with low Sc concentration1-xScxN layer or high Sc concentration Al1-yScyAnd the N layer is formed by adopting a magnetron sputtering method.
Preferably, in the step 6), a magnetron sputtering method is adopted, and the preparation process is as follows: the flow rate of nitrogen is 5-400 sccm, the flow rate of argon is 5-400 sccm, the total pressure in the chamber is 0.1-10pa, the sputtering power is 0.1-15 KW, and the temperature is 30-1000 ℃;
preferably, in the step 7), a magnetron sputtering method is adopted, and the preparation process is as follows: the flow rate of the nitrogen is 5-400 sccm, the flow rate of the argon is 5-200 sccm, the total pressure in the chamber is 0.1-5pa, the sputtering power is 0.1-15 KW, and the temperature is 30-600 ℃.
The invention has the following beneficial effects:
the preparation method can be used for preparing the AlScN film with high crystallization quality, high phase velocity, low surface roughness, high temperature stability and high Sc concentration. Compared with the traditional Si substrate, the silicon carbide substrate can reduce the adverse effect caused by lattice mismatch and can provide higher phase velocity. By means of SiO2The layer can make up the drawback of the high Sc concentration AlScN film temperature stability difference. In SiO2The growth of an Al layer on the film can effectively passivate SiO2Film, preventing formation of amorphous SiNxAnd simultaneously providing a buffer layer for the next step of growing AlN. An AlN seed layer grows on the Al layer, lattice mismatch with AlScN is smaller, crystallization quality can be improved, generation of abnormal nucleation can be effectively inhibited, and loss of phase velocity of the AlScN thin film can be compensated. First growing low Sc Al on AlN seed layer1-XScXAnd the N layer prevents Sc element from being separated out in advance, reduces the potential barrier difference between the last barrier layer and the barrier layer, namely reduces lattice mismatch between the last barrier layer and the barrier layer, avoids introducing large strain and a polarization field, reduces potential barrier peak formed by the valence band of the electron blocking layer, and reduces obstruction of hole injection. Finally growing Al with high Sc concentration1-yScyAnd the N layer improves the piezoelectric performance of the multilayer structure. The template prepared by adopting the multilayer structure can be better suitable for the application of devices based on bulk acoustic waves and surface acoustic waves, such as sensors, drivers, microfluid based on surface acoustic waves and the like.
Drawings
FIG. 1 shows silicon carbide-based Al of the present invention1-xScxAnd (3) a schematic flow diagram of the preparation of the N template.
FIG. 2 shows silicon carbide-based Al of the present invention1-xScxAnd (4) a flow chart of an N template preparation structure.
FIG. 3 is the rocking curve diagram (left) of the X-ray 002 diffraction of the silicon carbide-based AlScN template of example 1 of the present invention and the morphology diagram (right) of the atomic force microscope thereof.
FIG. 4 is the X-ray 002 diffraction rocking curve (left) and the atomic force microscope topography (right) of the silicon carbide-based AlScN template of the conventional structure of comparative example 1.
Detailed Description
For a further understanding of the invention, reference will now be made to the preferred embodiments of the invention by way of example, and it is to be understood that the description is intended to further illustrate features and advantages of the invention, and not to limit the scope of the claims.
Example 1
A silicon carbide-based AlScN template structure for a high-frequency high-performance SAW device and a preparation method thereof mainly comprise the following steps: preparation of silicon carbide substrate 1 (S1), pretreatment of substrate surface (S2), SiO growth2Layer 2 (S3), growing Al layer 3 (S4), growing AlN seed layer 4 (S5), growing Al1-xScxN Low Sc concentration layer 5 (S6), growing Al1-xScxN high Sc concentration layer 6 (S7). Fig. 1 and 2 show a schematic flow chart of the preparation of the silicon carbide-based AlScN template and a schematic process of the preparation of the silicon carbide-based AlScN template in this embodiment, respectively. The structure and the preparation method of the silicon carbide-based AlScN template of this embodiment are described in detail below with reference to the accompanying drawings.
1) A silicon carbide substrate 1 is prepared (S1). The crystal orientation of the silicon carbide substrate 1 is (0001), the crystal form is 4H, the conductive type is semi-insulating, the substrate is polished, the surface is an EPI-ready polished surface cleaned by RCA, the roughness is less than 0.3 nm, the back surface is a grinding grade, and the roughness is 1 +/-0.2 mu m.
2) The surface of the silicon carbide substrate 1 is pretreated (S2). Adopting an ion bombardment technology, and the pretreatment conditions are as follows: the RF power is 20W, the argon flow range is 300sccm, and the duration is 60 s. Through ion bombardment pretreatment, oxide impurities on the surface of the substrate material can be removed, and along with the accumulation of bombardment energy, the activity and the migration capacity of adsorbed atoms are enhanced.
3) Growing SiO2Layer 2 (S3). Preparation of 100nm SiO2The layer compensates for the temperature stability of the device.
4）The aluminum metal layer 3 is grown (S4). The 10nm Al layer is prepared by adopting a magnetron sputtering technology, and SiO can be effectively passivated2Thin film, effectively preventing amorphous SiN formationx。
5) An AlN seed layer 4 is grown (S5). A magnetron sputtering method is adopted, the pressure of the reaction chamber is 0.1 pa, the flow rate of nitrogen is 100 sccm, the flow rate of argon is 10 sccm, the sputtering power is 1 KW, the temperature is 300 ℃, and the film thickness is 500 nm. The AlN seed layer can make up for AlScN phase speed loss, has smaller lattice mismatch with AlScN, improves the crystallization quality and reduces abnormal nucleation.
6) Growing Al0.9Sc0.1N low Sc concentration layer 5 (S6). A magnetron sputtering method (Sputter) is adopted, the content of Sc element in the AlSc alloy target is 15at%, the pressure of a reaction chamber is 0.1 pa, the flow of nitrogen is 100 sccm, the flow of argon is 10 sccm, the sputtering power is 3 KW, the temperature is 250 ℃, and the film thickness is 300 nm. The low Sc concentration layer prevents Sc elements from being separated out in advance, the potential barrier difference of the valence band between the last barrier layer and the upper high concentration AlScN layer is reduced, namely lattice mismatch between the last barrier layer and the upper high concentration AlScN layer is reduced, large strain and a polarization field are prevented from being introduced, potential barrier peaks formed by the valence band of the electron blocking layer are reduced, and the obstruction of hole injection is reduced;
7) growing Al0.57Sc0.43N high Sc concentration layer 6 (S7). A magnetron sputtering method (Sputter) is adopted, the content of Sc element in the AlSc alloy target material is 43 +/-1 at%, the pressure of a reaction chamber is 0.1 pa, the nitrogen flow is 100 sccm, the argon flow is 10 sccm, the sputtering power is 4 KW, the temperature is 200 ℃, and the film thickness is 1000 nm. The silicon carbide-based AlScN template of the present example was prepared.
Example 2
Still, referring to fig. 1 and 2, the silicon carbide-based AlScN template structure and the preparation method of the present embodiment will be described in detail with reference to the accompanying drawings.
1) A silicon carbide substrate material 1 is prepared (S1). The silicon carbide substrate 1 is a standard specification polishing substrate sheet produced, the surface is an EPI-ready polished surface cleaned by RCA, the roughness is less than 0.3 nm, the back surface is a grinding grade, and the roughness is 1 +/-0.2 mu m.
2) The surface of the substrate 1 is pretreated (S2). The pretreatment conditions are as follows: the RF power is 20W, the argon flow range is 300sccm, and the duration is 60 s. By adopting a pretreatment technology, oxide impurities on the surface of the substrate material can be removed, bombardment energy is accumulated, and the activity and the migration capability of adsorbed atoms are enhanced.
3) Growing SiO2Layer 2 (S3). Preparation of 100nm SiO2Layer, make up for temperature stability.
4) The tungsten metal layer 3 is grown (S4). The magnetron sputtering technology is adopted to prepare the 200nm tungsten metal layer, and SiO can be effectively passivated2Thin film, effectively preventing amorphous SiN formationx。
5) An AlN seed layer 4 is grown (S5). An AlN buffer layer is grown by using an MOCVD technology, trimethylaluminum and ammonia gas are used as raw materials for preparing the AlN thin film, and the thickness of the film is 500 nm. The AlN seed layer can make up for AlScN phase speed loss, has smaller lattice mismatch with AlScN, improves the crystallization quality and reduces abnormal nucleation.
6) Growing Al0.8Sc0.2N low Sc concentration layer 5 (S6). A magnetron sputtering method (Sputter) is adopted, the content of Sc element in the AlSc alloy target is 20 +/-1 at%, the pressure of a reaction chamber is 0.1 pa, the nitrogen flow is 90 sccm, the argon flow is 15sccm, the sputtering power is 3 KW, the temperature is 250 ℃, and the film thickness is 500 nm. The low Sc concentration layer prevents Sc elements from being separated out in advance, lowers the potential barrier difference between the last barrier layer and the barrier layer, namely lowers lattice mismatch between the last barrier layer and the barrier layer, avoids introducing large strain and a polarization field, reduces potential barrier peaks formed by the valence band of the electron blocking layer, and reduces obstruction of hole injection;
7) growing Al0.68Sc0.32N high Sc concentration layer 6 (S7). A magnetron sputtering method (Sputter) is adopted, the content of Sc element in the AlSc alloy target is 32 +/-1 at%, the pressure of a reaction chamber is 0.1 pa, the nitrogen flow is 100 sccm, the argon flow is 6sccm, the sputtering power is 4 KW, the temperature is 200 ℃, and the film thickness is 500 nm. The silicon carbide-based AlScN template of the present example was prepared.
Comparative example 1
In the comparative example, the AlScN template with the conventional structure prepared by the conventional method is adopted, and the high-concentration AlScN layer is directly deposited on the silicon carbide substrate, and the steps are as follows:
1) same as step 1) of example 1, a silicon carbide substrate was prepared: the silicon carbide substrate is a single crystal and polished substrate slice with standard specification, the surface is an EPI-ready polished surface cleaned by RCA, the roughness is less than 0.3 nm, the back surface is a grinding grade, and the roughness is 1 +/-0.2 mu m.
2) The same as step 2) of example 1, the surface of the silicon carbide substrate 1 was pretreated: adopting an ion bombardment technology, and the pretreatment conditions are as follows: the RF power is 20W, the argon flow range is 300sccm, and the duration is 60 s. Through ion bombardment pretreatment, oxide impurities on the surface of the substrate material can be removed, and along with the accumulation of bombardment energy, the activity and the migration capacity of adsorbed atoms are enhanced.
3) Same as step 7) of example 1, Al was grown0.57Sc0.43N high Sc concentration layer. A magnetron sputtering method (Sputter) is adopted, the pressure of the reaction chamber is 0.1 pa, the flow of nitrogen is 100 sccm, the flow of argon is 10 sccm, the sputtering power is 4 KW, the temperature is 200 ℃, and the film thickness is 1000 nm.
The silicon carbide-based AlScN templates prepared in the examples and comparative examples were subjected to various performance tests, and the crystal quality and surface roughness thereof were measured by a rocking curve and an atomic force microscope. Referring to FIGS. 3 and 4, the rocking curve test pattern and the AFM test pattern of the silicon carbide-based AlScN template prepared in example 1 and comparative example 1 are shown, respectively, and it can be seen from the results of the test in the figure that the silicon carbide-based AlScN template prepared in example 1 has HRXRD half height & width @ (002) of 1.4 degrees and surface roughness RMS value of 2-3 nm; the silicon carbide-based AlScN template prepared in comparative example 1 had a HRXRD full width at half maximum @ (002) of 2.5 deg., and a surface roughness RMS value of 8-10 nm. Although the parameters of the silicon carbide substrate and the process for forming the AlScN layer on the surface layer used in example 1 and comparative example 1 are completely the same, it is obvious that in example 1, since the AlN seed layer and the AlScN transition layer with low Sc concentration are added, Al with high Sc-doped concentration is finally obtained1-xScxThe N thin film layer has high crystallization quality and few abnormal nucleation, and can effectively improve the electric coupling coefficient. The data for each particular test is set forth in Table 1.
The silicon carbide substrates produced in the examples and comparative examples were also testedPiezoelectric properties, phase velocity and frequency temperature coefficient of the AlScN template. The respective test data are also shown in table 1. Test results show that the silicon carbide-based AlScN template can effectively increase the phase velocity, such as 3600m/s in the comparative example, 5500m/s in the embodiment 1 and 5700m/s in the embodiment 2, and meets the requirements of high-frequency SAW devices. Meanwhile, the data in the table can show that the Al with high Sc-doped concentration prepared by the invention1-xScxThe temperature coefficient of frequency of the N thin film layer is low, such that the temperature coefficient of frequency is reduced to-13.51 ppm/K as in example 2, compared with SiO in comparative example 12The layer acts to improve temperature stability. The silicon carbide-based AlScN template structure and the preparation method thereof provide a solution for SAW devices with high frequency, high performance and high electromechanical coupling coefficient.
TABLE 1 comparison of the Performance parameters of AlScN templates prepared in the examples and comparative examples
Figure DEST_PATH_IMAGE002
The above description of the embodiments is only intended to facilitate the understanding of the method of the invention and its core idea. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.

Claims (10)

1. A silicon carbide-based AlScN template for a high-frequency high-performance SAW device is characterized in that: the silicon carbide-based AlScN template is of a multilayer structure, single crystal silicon carbide is used as a substrate, and SiO grows on the polished surface of the silicon carbide in sequence2The device comprises a layer, a metal passivation layer, an AlN seed layer, a low-concentration Sc-doped AlScN layer and a high-concentration Sc-doped AlScN layer;
wherein: the chemical formula of the low-concentration Sc-doped AlScN layer is Al1-xScxN, wherein x is less than or equal to 0.3; the chemical formula of the high-concentration Sc-doped AlScN layer is Al1-yScyN, wherein y is more than or equal to 0.3 and less than or equal to 0.6.
2. The silicon carbide-based AlScN template for the high-frequency high-performance SAW device as claimed in claim 1, wherein: the SiO2The thickness of the layer film is 10-1000nm, and the thickness of the metal passivation layer film is 5-1000 nm; the thickness of the AlN seed layer is 10-5000 nm; the thickness of the low-concentration Sc-doped AlScN layer is 10-5000 nm; the thickness of the high-concentration Sc-doped AlScN layer is 10-5000 nm.
3. The silicon carbide-based AlScN template for the high-frequency high-performance SAW device as claimed in claim 1, wherein: the silicon carbide-based AlScN template has the frequency temperature coefficient lower than-14.73 ppm/K and the phase velocity higher than 5500 m/s.
4. A method for preparing a silicon carbide-based AlScN template for high frequency high performance SAW devices as claimed in any one of claims 1 to 3, comprising the steps of:
1) preparing a silicon carbide substrate; the silicon carbide substrate adopts a single-side polished single wafer;
2) pretreating the surface of the silicon carbide substrate;
3) preparing SiO on the surface of the pretreated silicon carbide substrate2A layer;
4) in SiO2Preparing a metal layer on the layer;
5) preparing an AlN seed layer on the metal layer;
6) preparing Al with low Sc concentration on an AlN seed layer1-xScxN layers, wherein x is less than or equal to 0.3;
7) al at the low Sc concentration1-xScxPreparation of high Sc concentration Al on N layer1-yScyAnd y is more than or equal to 0.3 and less than or equal to 0.6.
5. The method for preparing the silicon carbide-based AlScN template for the high-frequency high-performance SAW device according to claim 4, wherein: and 2) removing the oxide and the pollutants on the surface of the silicon carbide substrate by adopting an ion bombardment method.
6. The method for preparing the silicon carbide-based AlScN template for the high-frequency high-performance SAW device according to claim 4, wherein: and 5) growing the AlN seed layer by adopting an MOCVD method or a magnetron sputtering method.
7. The method for preparing the silicon carbide-based AlScN template for the high-frequency high-performance SAW device according to claim 4, wherein: step 6) or step 7) adopts a magnetron sputtering method.
8. The method for preparing the silicon carbide-based AlScN template for the high-frequency high-performance SAW device according to claim 7, wherein: in the step 6), the preparation process adopting the magnetron sputtering method comprises the following steps: the flow rate of the nitrogen is 5-400 sccm, the flow rate of the argon is 5-400 sccm, the total pressure in the chamber is 0.1-10pa, the sputtering power is 0.1-15 KW, and the temperature is 30-1000 ℃.
9. The method for preparing the silicon carbide-based AlScN template for the high-frequency high-performance SAW device according to claim 7, wherein: in the step 7), the preparation process adopting the magnetron sputtering method comprises the following steps: the flow rate of the nitrogen is 5-400 sccm, the flow rate of the argon is 5-200 sccm, the total pressure in the chamber is 0.1-5pa, the sputtering power is 0.1-15 KW, and the temperature is 30-600 ℃.
10. The method for preparing the silicon carbide-based AlScN template for the high-frequency high-performance SAW device according to claim 4, wherein: the metal layer is a metal Al layer or a metal tungsten layer.
CN202110971256.7A 2021-08-24 2021-08-24 Silicon carbide-based AlScN template for high-frequency high-performance SAW device and preparation method thereof Pending CN113871289A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116682916A (en) * 2023-08-03 2023-09-01 江西兆驰半导体有限公司 Multi-quantum well layer, preparation method thereof, epitaxial wafer and light-emitting diode

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116682916A (en) * 2023-08-03 2023-09-01 江西兆驰半导体有限公司 Multi-quantum well layer, preparation method thereof, epitaxial wafer and light-emitting diode
CN116682916B (en) * 2023-08-03 2023-11-21 江西兆驰半导体有限公司 Multi-quantum well layer, preparation method thereof, epitaxial wafer and light-emitting diode

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