An amorphous boron nitride-based redistribution layer transmission line and a preparation method thereof

Abstract

The application discloses a kind of based on amorphous boron nitride redistribution layer transmission line and preparation method thereof, the preparation method includes preparation cleaning, depositing the first dielectric layer of amorphous boron nitride, forming photoresist mask, depositing the conductor of transmission line conductor of conductive material, remove mask, depositing the second dielectric layer of amorphous boron nitride, obtain amorphous boron nitride medium coated redistribution layer transmission line structure.The structure takes amorphous boron nitride as core dielectric layer, replaces traditional SiO2, BCB and so on medium, realizes lower insertion loss under the same thickness, substantially reduces high-frequency transmission loss and improves link transmission performance, and preparation process is compatible with existing semiconductor micro-nano processing technology, can be applied to the RDL layer of heterogeneous three-dimensional integrated structure, satisfies high-frequency high-speed signal interconnection demand.

Description

Technical Field

[0001] This invention relates to the field of high-frequency high-speed interconnect and microwave / millimeter-wave transmission technology, and in particular to a redistribution layer transmission line based on amorphous boron nitride and its fabrication method. Background Technology

[0002] With the rapid evolution of 5G / 6G communication, AI chips, heterogeneous integration, and high-bandwidth interconnect technologies, the demands on signal transmission rates in electronic systems are increasing exponentially. Whether it's the redistribution layer (RDL) in advanced packaging or high-density multilayer printed circuit boards (PCBs), the interconnect quality of high-frequency signals has become a core factor determining the overall performance of electronic systems. This places extremely high demands on the dielectric constant (Dk) and loss characteristics (Df) of transmission line dielectric materials, putting traditional dielectric materials to the test.

[0003] Currently, the industry widely uses silicon dioxide (SiO2, glass) or polymers (such as PI) as dielectric materials for RDLs and multilayer PCBs. However, when applications move into high-frequency and microwave bands, the limitations of existing dielectric materials become apparent. SiO2 has a relatively high dielectric constant. This easily leads to severe parasitic capacitance effects at high frequencies, resulting in significant signal RC delay. On the other hand, although traditional polymers can reduce the dielectric constant to some extent, their dielectric loss tangent remains relatively large under high-frequency alternating electric fields. The inherent absorption loss of this material causes extremely severe insertion loss, resulting in drastic attenuation of high-frequency signals in the transmission link, limiting the performance improvement potential of high-speed interconnect systems.

[0004] Furthermore, in high-frequency RDL transmission line applications, the thickness uniformity, in-plane roughness, and large-area deposition consistency of the dielectric layer significantly affect the impedance uniformity and loss stability of the transmission line. Traditional dielectric solutions or some thin film materials suffer from limited process windows in achieving large thicknesses while maintaining low roughness and good uniformity. Therefore, there is an urgent need for a process and structural solution capable of fabricating high-thickness, uniform, and flat low-k dielectric thin films on large-area substrates to meet the engineering application requirements of high-frequency, high-speed interconnects.

[0005] Therefore, overcoming the performance limitations of traditional dielectric materials has become a core technology that the industry urgently needs to master. There is a pressing need to develop a new type of dielectric material and transmission line architecture that can be simultaneously packaged in advanced wiring layers and multilayer high-speed circuit structures to achieve ultra-low dielectric constant and extremely low high-frequency loss. Furthermore, this solution must be highly compatible with common micro / nano fabrication and lamination processes, and ensure the flatness of the processed material surface, in order to fundamentally reduce transmission loss in millimeter-wave and higher frequency bands, and comprehensively improve the interconnect reliability of next-generation chip heterogeneous integration systems. Summary of the Invention

[0006] To address the above technical problems, this invention discloses a redistribution layer transmission line based on amorphous boron nitride and its fabrication method. Using amorphous boron nitride (a-BN) as the core dielectric material, it solves the problems of high high-frequency loss, poor deposition uniformity, and low process compatibility of traditional dielectric layers, and achieves low-loss transmission of high-frequency and high-speed signals.

[0007] The technical solution adopted by this invention is as follows:

[0008] A method for fabricating a redistribution layer transmission line based on amorphous boron nitride includes the following steps:

[0009] Step S1, prepare the substrate;

[0010] Step S2, depositing a first dielectric layer on the substrate, wherein the material of the first dielectric layer is amorphous boron nitride;

[0011] Step S3: A patterned photoresist mask is formed on the first dielectric layer;

[0012] Step S4: Deposit conductive material within the area defined by the photoresist mask to form a transmission line conductor;

[0013] Step S5: Remove the photoresist mask;

[0014] Step S6: Deposit a second dielectric layer on at least the transmission line conductor, wherein the material of the second dielectric layer is amorphous boron nitride, to obtain a redistribution layer transmission line structure covered by amorphous boron nitride dielectric.

[0015] This technical solution utilizes amorphous boron nitride (a-BN) as the main material for the dielectric layer. This material is grown via magnetron sputtering and applied to high-frequency / high-speed transmission lines. This amorphous network structure eliminates grain boundary defects in traditional crystalline materials that easily induce leakage and electromagnetic scattering, resulting in an extremely low tangent loss angle. Using it as the insulating dielectric for high-frequency / high-speed transmission lines enables lower insertion loss and improved high-frequency transmission performance. Simultaneously, this thin-film deposition process allows for the fabrication of large-area, high-thickness, uniform, and highly flat thin films of a-BN on the substrate, further enhancing high-frequency and high-speed transmission capabilities. Furthermore, the deposition temperature can reach room temperature, and it exhibits better compatibility with existing semiconductor processes, making it suitable for mass production. This provides an ultra-low interconnect loss fabrication method for high-speed, high-frequency circuit structures in heterogeneous chip interconnect integration.

[0016] As a further improvement of the present invention, the deposition process in step S2 and / or step S6 adopts the magnetron sputtering process of physical vapor deposition, and the sputtering target is boron nitride.

[0017] As a further improvement of the present invention, the magnetron sputtering process adopts radio frequency mode, and the radio frequency power during the deposition process is 80 W to 300 W.

[0018] As a further improvement of the present invention, the substrate temperature during the deposition process is room temperature to 500°C.

[0019] As a further improvement of the present invention, the process gas in the deposition process is a mixture of argon and nitrogen, and the flow ratio of argon to nitrogen is 1 to 4:1.

[0020] As a further improvement of the present invention, the gas pressure inside the magnetron sputtering cavity is 0.01~1 Pa.

[0021] As a further improvement of the present invention, the radio frequency power is preferably 120 W to 180 W, the substrate temperature is preferably 60℃ to 300℃, and the flow ratio of argon to nitrogen is preferably 3:1 to 3:2.

[0022] As a further improvement of the present invention, the thickness of the first dielectric layer and / or the second dielectric layer is independently 10 nm to 20000 nm.

[0023] As a further improvement of the present invention, the substrate is a silicon substrate or a glass substrate.

[0024] As a further improvement of the present invention, the conductive material comprises at least one selected from copper, gold, silver, and aluminum. Copper is preferred.

[0025] As a further improvement of the present invention, the thickness of the transmission line conductor is 0.2 μm to 50 μm.

[0026] As a further improvement of the present invention, the method of forming the pattern in step S3 includes ultraviolet exposure development, electron beam exposure or laser direct writing.

[0027] As a further improvement of the present invention, before depositing the conductive material in step S4, a step of depositing a barrier layer and / or an adhesive layer is included, wherein the material of the barrier layer and / or adhesive layer comprises one or more combinations of titanium, titanium nitride, tantalum, tantalum nitride, tungsten, and chromium.

[0028] As a further improvement of the present invention, the method of depositing conductive material in step S4 includes a combination of magnetron sputtering seed layer and electroplating thickening, or magnetron sputtering alone.

[0029] As a further improvement of the present invention, step S1 includes ultrasonic cleaning of the substrate using isopropanol and deionized water.

[0030] This invention discloses a redistribution layer transmission line based on amorphous boron nitride, which is fabricated using the method described above for preparing a redistribution layer transmission line based on amorphous boron nitride. The redistribution layer includes: a substrate; a first dielectric layer located on the substrate, wherein the material of the first dielectric layer comprises amorphous boron nitride; a transmission line conductor located on the first dielectric layer; and a second dielectric layer covering the transmission line conductor, wherein the material of the second dielectric layer comprises amorphous boron nitride.

[0031] As a further improvement of the present invention, the transmission line conductor is at least one of a microstrip line, a coplanar waveguide, or a stripline structure.

[0032] This invention discloses the application of the redistribution layer transmission line based on amorphous boron nitride in redistribution layers of heterogeneous integrated stacked structures, multilayer high-speed circuit structures, or high-frequency / high-speed signal transmission.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0034] First, this invention uses amorphous boron nitride as the upper and lower dielectric layers of the transmission line. Its unique amorphous network structure eliminates grain boundary defects, resulting in extremely low dielectric constant and dielectric loss tangent. Compared with transmission lines using traditional dielectrics such as silicon dioxide or benzocyclobutene, it exhibits lower transmission loss under the same structure and thickness conditions, significantly reducing the insertion loss (S0) of high-frequency signals. 21 Furthermore, it exhibits lower attenuation per unit length, thereby improving link transmission performance.

[0035] Second, it offers high process compatibility: amorphous boron nitride thin films can be deposited at room temperature or lower temperatures via magnetron sputtering, making them highly compatible with existing semiconductor processes. This process can prepare dielectric thin films with uniform thickness and high surface flatness on large-area substrates, meeting the needs of mass production, and is easily integrated into existing redistribution layer manufacturing processes.

[0036] Third, structural stability and performance consistency: By forming amorphous boron nitride dielectric layers above and below the conductor, a uniform dielectric environment is provided for the conductor, stabilizing the electromagnetic field boundary conditions. This helps reduce signal distortion and additional losses caused by dielectric inhomogeneity, and improves the performance consistency of the transmission line in the high-frequency band.

[0037] Fourth, it has a wide range of applications: by adjusting the thickness of the a-BN dielectric layer, the conductor thickness, and the conductor structure, it can adapt to the interconnection requirements of different linewidths and different high-frequency bands, and can be widely used in high-frequency and high-speed signal interconnection in fields such as 5G / 6G communication, AI chips, heterogeneous integrated stacked packaging, and multilayer high-speed PCB. Attached Figure Description

[0038] Figure 1The diagram shows the fabrication process and physical structure of the redistribution layer transmission line based on amorphous boron nitride provided by the present invention; wherein, (a) is a schematic diagram of the fabrication process and (b) is a physical structure diagram.

[0039] Figure 2 This is a flowchart of the magnetron sputtering deposition of amorphous boron nitride according to the present invention.

[0040] Figure 3 The surface roughness planar distribution diagram is shown for the amorphous boron nitride thin film prepared in this invention with a thickness of 500 nm; where (a) is Example 1 and (b) is Comparative Example 1.

[0041] Figure 4 The image shows the Raman spectrum of the amorphous boron nitride thin film of Example 1 of the present invention under 532 nm excitation.

[0042] Figure 5 This is a graph showing the relative permittivity of the amorphous boron nitride dielectric material of Embodiment 1 of the present invention as a function of frequency.

[0043] Figure 6 The insertion loss S in the transmission line structure of Embodiment 1 and Comparative Example 2 of this invention is the difference between amorphous boron nitride dielectric layers of different thicknesses and SiO2 dielectric layers of the same thickness. 21 Comparison figures; where the thicknesses of (a) to (d) are 120 nm, 300 nm, 500 nm, and 700 nm, respectively.

[0044] Figure 7 This is a comparison diagram of transmission attenuation under different medium thicknesses for different media in Embodiment 1 and Comparative Example 3 of the present invention. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0046] A method for fabricating a redistribution layer transmission line based on amorphous boron nitride, such as... Figure 1 As shown, it includes the following steps:

[0047] S1. Substrate preparation: Provide a clean silicon substrate and perform routine cleaning and drying on the substrate.

[0048] S2. Deposit the first a-BN dielectric layer: Deposit an a-BN thin film on the surface of a silicon substrate as the first dielectric layer using a thin film deposition process; the thickness of the a-BN thin film can be selected according to design requirements, for example, one or more values ​​in the range of 10 nm to 20000 nm.

[0049] S3. Photolithography patterning: Photoresist is spin-coated onto the surface of the first dielectric layer, and a photoresist pattern for defining the transmission line conductor is formed by ultraviolet exposure and development.

[0050] S4. Forming a conductive layer: Deposit a conductive layer on a wafer with a photoresist pattern to form a coplanar waveguide (CPW) conductive path and transmission line conductor. The conductive layer is preferably a copper layer. The deposition method can be magnetron sputtering, and the target thickness can be obtained by further using the method of "sputtering seed layer + electroplating thickening" as needed.

[0051] S5. Photoresist Removal: Removes the photoresist pattern while preserving the patterned conductor structure.

[0052] S6. Deposit a second a-BN dielectric layer: Deposit a-BN thin film as a second dielectric layer on the conductor structure and the first dielectric layer to cover / encapsulate the conductor, thereby obtaining a high-frequency transmission line with an a-BN / copper / a-BN stack or equivalent encapsulation structure.

[0053] Optionally, in step S1, the cleaning method includes, but is not limited to, ultrasonic treatment with isopropanol and deionized water.

[0054] Optionally, in steps S2 and 6, the thickness of the deposited a-BN is one or more values ​​in the range of 10 nm to 20000 nm.

[0055] Optionally, in steps S2 and S6, the deposition of a-BN can be magnetron sputtering, and the sputtering target is boron nitride.

[0056] like Figure 2 As shown, the a-BN deposition process in steps S2 and S6 includes: placing a boron nitride target at the magnetron sputtering RF source, placing the cleaned silicon wafer in the sample holder, and heating the silicon substrate at a temperature selectable from room temperature to 500°C. After the vacuum level in the magnetron cavity reaches 10 Pa, oxygen and nitrogen are introduced, with a flow rate ratio selectable from 1:1 to 4:1. After the gas pressure in the magnetron cavity stabilizes (0.01 Pa to 1 Pa), sputtering deposition begins. The target power can be selected from 80 W to 300 W.

[0057] In steps S2 and S6, the magnetron power for depositing a-BN is preferably 120W~180W.

[0058] In steps S2 and S6, the substrate for depositing a-BN is preferably set at 60°C to 300°C.

[0059] In steps S2 and 6, the preferred flow ratio of Ar:N2 in the magnetron sputtering cavity is 3:1 to 3:2.

[0060] Optionally, in step S3, photolithography patterning can also be performed using electron beam exposure or laser direct writing.

[0061] Optionally, in step S4, a barrier layer and / or an adhesion layer (e.g., Ti / TiN, Ta / TaN, etc.) may be deposited before depositing the conductor to improve interface stability and reliability.

[0062] Optionally, in step S5, acetone or N-methylpyrrolidone (NMP) or a dedicated adhesive remover can be used for degumming.

[0063] Optionally, in step S6, the above steps can be repeated to form a multi-layer RDL structure.

[0064] The following description uses specific examples to illustrate the point.

[0065] Example 1

[0066] A redistribution layer transmission line based on amorphous boron nitride, the fabrication process of which includes the following steps:

[0067] Step S1, Substrate Preparation: Provide a clean silicon substrate with a thickness of approximately 650 μm. The substrate is then ultrasonically cleaned in isopropanol and deionized water, followed by drying.

[0068] Step S2: Deposition of the first dielectric layer: An amorphous boron nitride thin film is deposited as the first dielectric layer on the cleaned silicon substrate using radio frequency magnetron sputtering. The sputtering target is boron nitride, and the process parameters are: radio frequency power 120W, substrate temperature 300℃, process gases are argon and nitrogen with a flow ratio of Ar:N2 = 3:1, and chamber pressure 1 Pa. The deposition thickness is 120nm.

[0069] Step S3, Photolithography Patterning: Photoresist is spin-coated onto the substrate surface on which the first dielectric layer is deposited, and a patterned photoresist mask for defining the coplanar waveguide transmission line conductor is formed by ultraviolet exposure and development.

[0070] Step S4: Forming a conductive layer: On a wafer with a photoresist mask, a titanium / copper layer is first magnetron sputtered as a seed layer, and then the copper layer is thickened by electroplating to finally form a coplanar waveguide structure with a thickness of about 0.7 μm.

[0071] Step S5, Removal: Use acetone solution to remove the photoresist mask, exposing the patterned copper conductor structure.

[0072] Step S6: Deposit the second dielectric layer: Using the same process parameters as in step S2, deposit amorphous boron nitride films of different thicknesses as the second dielectric layer on the copper conductor and the exposed first dielectric layer to obtain samples with different second dielectric layer thicknesses, namely 120 nm, 300 nm, 500 nm and 700 nm, to achieve complete coverage of the conductor and obtain a high-frequency transmission line with a sandwich structure of amorphous boron nitride / copper / amorphous boron nitride.

[0073] Comparative Example 1

[0074] Based on Example 1, the difference in this comparative example lies in the different preparation process parameters. Specifically, the radio frequency power is 60W, the substrate is set to room temperature, the process gases are argon and nitrogen with a flow ratio of Ar:N2 = 3:1, and the chamber pressure is 1Pa.

[0075] Example 2

[0076] The amorphous boron nitride thin film prepared in Example 1 was characterized in terms of its material and electrical properties.

[0077] like Figure 3 As shown in (a), a 500 nm thick amorphous boron nitride film was characterized by confocal microscopy with a scanning area of ​​230 μm × 230 μm. The results showed that the film surface had small undulations and the in-plane root mean square roughness Rq was only 5 nm, indicating that the technical solution of the present invention in Example 1 can obtain a dielectric film with high flatness.

[0078] If the preferred process parameters of this invention are deviated from, and the technical solution of Comparative Example 1 is used, the in-plane roughness of the prepared a-BN film is Rq=32 nm, resulting in large surface undulations, which easily causes discontinuities in the dielectric constant and additional transmission losses, such as... Figure 3 As shown in (b) of the diagram.

[0079] like Figure 4 As shown, Raman spectroscopy was performed under 532 nm excitation, and no characteristic Raman peaks of traditional hexagonal boron nitride (h-BN) were observed, proving that the prepared film has an amorphous a-BN structure and no grain boundary defects.

[0080] like Figure 5 As shown, through high-frequency dielectric performance testing, the relative dielectric constant of a-BN thin film in the 1.8–2.2 GHz frequency band is much lower than that of SiO2 (the dielectric constant of SiO2 is ≈4), and the dielectric constant fluctuates little with frequency, showing excellent stability.

[0081] Example 3

[0082] An application scenario for a redistribution layer transmission line based on amorphous boron nitride. The transmission line structure obtained in Example 1 is applied to the redistribution layer of a heterogeneous integrated stacked package as a transmission unit for high-speed signal interconnection to reduce link loss.

[0083] To verify the high-frequency transmission performance of the transmission line of the present invention, Comparative Example 2 (SiO2 as the dielectric layer) and Comparative Example 3 (benzocyclobutene (BCB) as the dielectric layer) were set up. The substrate, conductor material / thickness, and transmission line structure of each comparative example were completely the same as those of Example 1, except that the dielectric layer was replaced with SiO2 and BCB, and the dielectric layer thickness was the same as that of the a-BN dielectric layer in Example 1.

[0084] Comparative Example 2

[0085] A transmission line structure using silicon dioxide as the dielectric layer is prepared by the following steps: (1) Substrate preparation: The same silicon substrate as in Example 1 is used and cleaned. (2) Formation of the first dielectric layer: A silicon dioxide thin film is formed on the substrate using chemical vapor deposition. The thickness is the same as that of the amorphous boron nitride dielectric layer in Example 1, which is 120 nm, 300 nm, 500 nm and 700 nm respectively. (3) Conductor formation: A transmission line conductor with the same material (copper) and thickness (about 0.7 μm) as in Example 1 is formed by photolithography patterning and electroplating. (4) Formation of the overlay dielectric layer: A silicon dioxide layer of the same thickness is deposited again on top of the conductor as the second dielectric layer. (5) Performance testing: The insertion loss of the obtained comparative transmission line is tested, and the results are as follows. Figure 6 As shown.

[0086] Figure 6 The insertion loss of the transmission line structure using an amorphous boron nitride dielectric layer in Example 1 and a silicon dioxide dielectric layer in Comparative Example 2 was compared at dielectric thicknesses of 120 nm, 300 nm, 500 nm, and 700 nm. The results show that, at all thicknesses, especially in the high-frequency band of 40 GHz, the insertion loss of the transmission line using the amorphous boron nitride dielectric is significantly lower than that using the silicon dioxide dielectric, indicating that amorphous boron nitride can greatly reduce high-frequency transmission loss.

[0087] Comparative Example 3

[0088] A transmission line structure using benzocyclobutene as the dielectric layer is prepared by the following steps: (1) Substrate preparation: The same silicon substrate as in Example 1 is used and cleaned. (2) Dielectric layer formation: Benzocyclobutene is spin-coated onto the substrate and cured to form the first dielectric layer. After the conductor is formed, it is spin-coated and cured again to form the second dielectric layer. The dielectric layer thickness is basically the same as in Example 1. (3) Conductor formation: A transmission line conductor with the same material (copper) and thickness as in Example 1 is formed by photolithography patterning and electroplating. (4) Loss characterization: The obtained transmission line is subjected to a unit length attenuation test, and the results are as follows. Figure 7 As shown.

[0089] Figure 7 The comparison of the fitted transmission attenuation of a-BN and BCB media under different media thickness conditions shows that, under the same or similar media thickness conditions, the transmission line using amorphous boron nitride media consistently exhibits lower transmission attenuation per unit length than the sample using benzocyclobutene media, further confirming the superiority of the technical solution of this invention in reducing high-frequency signal transmission attenuation.

[0090] In summary, this invention successfully constructs an ultra-low-loss high-frequency transmission line structure by introducing amorphous boron nitride as the dielectric material for the redistribution layer and employing a compatible magnetron sputtering process. The mechanism by which this technology achieves its effect may be as follows:

[0091] (1) Reduce dielectric polarization loss and decrease dielectric loss terms.

[0092] When high-frequency signals propagate in a transmission line, part of the electromagnetic energy is stored in the dielectric. The polarization response of the dielectric material leads to energy dissipation, manifested as dielectric loss. α-BN, as a low dielectric constant material, has relatively low polarization intensity. Furthermore, as an amorphous material, it has a small tangent loss angle, thus reducing the dielectric loss term and ultimately resulting in a decrease in insertion loss and St. 21 improve.

[0093] (2) Reduce the equivalent capacitance per unit length;

[0094] Transmission lines can be characterized using a distributed parameter model, where the dielectric layer contributes capacitance C per unit length. Generally, the lower the dielectric constant, the smaller the capacitance per unit length. Reducing the capacitance per unit length decreases the frequency-sensitive loss components associated with the dielectric, resulting in improved performance in the high-frequency band (S). 21 Better.

[0095] (3) Sandwich / clad a-BN dielectric structure helps stabilize electric field boundary conditions.

[0096] This invention forms an a-BN dielectric layer (a-BN / conductor / a-BN) above and below the conductor, making the dielectric environment around the conductor more uniform and the electromagnetic boundary more stable. Improved dielectric environment uniformity can reduce local field distortion and additional energy dissipation caused by dielectric inhomogeneity, improve transmission consistency and reduce insertion loss.

[0097] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A method for fabricating a redistribution layer transmission line based on amorphous boron nitride, characterized in that, Includes the following steps: Step S1, prepare the substrate; Step S2, depositing a first dielectric layer on the substrate, wherein the material of the first dielectric layer is amorphous boron nitride; Step S3: A patterned photoresist mask is formed on the first dielectric layer; Step S4: Deposit conductive material within the area defined by the photoresist mask to form a transmission line conductor; Step S5: Remove the photoresist mask; Step S6: Deposit a second dielectric layer on at least the transmission line conductor, wherein the material of the second dielectric layer is amorphous boron nitride, to obtain a redistribution layer transmission line structure covered by amorphous boron nitride dielectric. The deposition process in steps S2 and S6 adopts the magnetron sputtering process of physical vapor deposition, and the sputtering target is boron nitride; the substrate temperature during the deposition process is room temperature to 500°C.

2. The method for fabricating a redistribution layer transmission line based on amorphous boron nitride according to claim 1, characterized in that: The magnetron sputtering process uses radio frequency mode, and the radio frequency power during the deposition process is 80 W to 300 W; the process gas during the deposition process is a mixture of argon and nitrogen, and the flow ratio of argon to nitrogen is 1 to 4:1; the gas pressure in the magnetron sputtering chamber is 0.01 to 1 Pa.

3. The method for fabricating a redistribution layer transmission line based on amorphous boron nitride according to claim 1, characterized in that: The thickness of the first dielectric layer and / or the second dielectric layer is independently 10 nm to 20000 nm.

4. The method for fabricating a redistribution layer transmission line based on amorphous boron nitride according to claim 1, characterized in that: The substrate is a silicon substrate or a glass substrate; the conductive material includes at least one of copper, gold, silver, and aluminum; and the thickness of the transmission line conductor is 0.2 μm to 50 μm.

5. The method for fabricating a redistribution layer transmission line based on amorphous boron nitride according to claim 1, characterized in that: The methods for forming the pattern in step S3 include ultraviolet exposure development, electron beam exposure, or laser direct writing.

6. The method for fabricating a redistribution layer transmission line based on amorphous boron nitride according to claim 1, characterized in that: Before depositing the conductive material in step S4, the method further includes depositing a barrier layer and / or an adhesive layer, wherein the material of the barrier layer and / or adhesive layer comprises one or more combinations of titanium, titanium nitride, tantalum, tantalum nitride, tungsten, and chromium. The methods for depositing conductive materials in step S4 include a combination of magnetron sputtering seed layer and electroplating thickening, or magnetron sputtering alone; Step S1 includes ultrasonic cleaning of the substrate using isopropanol and deionized water.

7. A redistribution layer transmission line based on amorphous boron nitride, characterized in that: The transmission line is prepared using the method described in any one of claims 1 to 6 for fabricating a redistribution layer based on amorphous boron nitride, comprising: Base; A first dielectric layer is located on the substrate, and the material of the first dielectric layer comprises amorphous boron nitride. The transmission line conductor is located on the first dielectric layer; A second dielectric layer covers the transmission line conductor, and the material of the second dielectric layer comprises amorphous boron nitride.

8. The redistribution layer transmission line based on amorphous boron nitride according to claim 7, characterized in that: The transmission line conductor is at least one of a microstrip line, a coplanar waveguide, or a stripline structure.

9. The application of the amorphous boron nitride-based redistribution transmission line as described in claim 7 in redistribution layers of heterogeneous integrated stacked structures, multilayer high-speed circuit structures, or high-frequency / high-speed signal transmission.

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