Ion beam composite regulation and control method for AI high-frequency high-speed electronic substrate

Abstract

The invention discloses an AI high-frequency high-speed electronic substrate-oriented ion beam composite regulation and control method, and relates to the technical field of semiconductor manufacturing and electronic packaging. Comprising the following steps: (1) carrying out ion implantation modification on the surface of a base material; (2) depositing and bonding a seed crystal layer by a magnetic filtering cathode vacuum arc; (3) depositing an ultralow-profile initial conductor layer through high-power pulse magnetron sputtering; (4) performing pulse electroplating to thicken the conductor; and (5) surface ion beam polishing. Through the dual effects of ion beam deposition and polishing, a conductor circuit with an extremely smooth surface is manufactured, the conductor loss of a millimeter wave frequency band is remarkably reduced, the dielectric property is improved by combining ion implantation, so that the insertion loss in a 50-60GHz frequency band can be stably controlled at-1.1 dB / inch or lower, and international leading technical indexes are benchmarked and even exceeded.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of semiconductor manufacturing and electronic packaging technology, and more particularly to an ion beam composite regulation method for AI high-frequency high-speed electronic substrates. BACKGROUND

[0002] With the explosive growth of artificial intelligence (AI) computing power and the evolution of wireless communication technology to millimeter wave frequency bands (such as 50-60GHz and higher), electronic substrates (such as chip packaging boards, high-frequency circuit boards, etc.) that carry and transmit high-frequency high-speed signals are facing unprecedented challenges. To meet this demand, network chips, as the core carrier of data transmission, are iterating towards "ultra-high bandwidth + ultra-high speed" - the next generation of products is expected to jump from the current mainstream 100T level to 200T, and the signal rate will also increase from 224G to 448G to support low-latency transmission of massive data. The integrity of the signal, especially the insertion loss, has become a core bottleneck restricting system performance. Insertion loss is mainly composed of dielectric loss and conductor loss. In the millimeter wave frequency band, the skin effect and surface roughness effect in conductor loss are particularly significant, and the signal current is concentrated in a very thin area on the surface of the conductor. Any slight surface unevenness will significantly increase the signal transmission path, resulting in serious signal attenuation and dispersion.

[0003] Currently, the industry generally uses ABF, MPI adhesive film, BT resin, and other low dielectric loss materials as substrates. However, in the manufacturing process of conductor lines, traditional "subtractive method" or "semi-additive method" (mSAP) process is difficult to form a flat profile and smooth surface of the conductor. Especially at the bonding interface with the polymer substrate, to ensure the bonding strength, the substrate usually needs to be roughened, which directly leads to the deterioration of the profile of the conductor bottom layer. At the same time, the crystalline morphology of the electroplated copper layer itself is also difficult to achieve nanoscale smoothness. These factors together lead to poor performance of the final product at high frequencies.

[0004] In addition, the bonding strength between the metal conductor layer and the ABF, MPI, and other polymer substrates is also a key technical difficulty. Insufficient bonding force can cause delamination, peeling, and other reliability problems under the action of thermal stress and mechanical stress. Existing surface treatment techniques, such as chemical roughening or plasma treatment, can improve the bonding force to some extent, but often at the expense of surface flatness, which is contrary to the requirements of high-frequency performance.

[0005] Ion beam technology, as a high-precision, atomic-scale material surface treatment and modification method, has shown great potential in semiconductor manufacturing. For example, ion implantation can precisely control the physicochemical properties of material surfaces; physical vapor deposition (PVD) techniques such as magnetron sputtering and vacuum arc deposition can prepare high-quality thin films; and ion beam polishing is used to achieve extreme smoothness of surfaces such as optical components. However, there are currently no publicly reported systematic and creative integrations of multiple ion beam technologies to form a complete process flow that synergistically solves the three core challenges of signal loss, surface profile, and bonding strength in high-frequency, high-speed substrates.

[0006] Therefore, there is an urgent need for an innovative manufacturing method that can minimize conductor profile and surface roughness while ensuring a strong bond between the conductor layer and the substrate, thereby achieving extremely low insertion loss and meeting the development needs of future AI and high-frequency communication technologies. Summary of the Invention

[0007] In view of this, the present invention provides a manufacturing technology for high-frequency, high-speed, ultra-low profile electronic substrates for applications such as artificial intelligence (AI), big data, and 5G / 6G communication. In particular, it provides an ion beam composite control method for AI high-frequency, high-speed electronic substrates, which aims to systematically solve the problems of high-frequency signal loss, uneven conductor profile, and insufficient adhesion between the metal layer and the substrate.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] An ion beam recombination control method for high-frequency, high-speed electronic substrates in AI includes the following steps:

[0010] (1) Surface modification of substrate by ion implantation

[0011] Before metallization, the polymer substrate is first pretreated by ion implantation, which uses a high-energy ion beam to bombard the substrate surface.

[0012] This step serves three purposes: 1) to break some chemical bonds on the polymer surface, forming active dangling bonds, thereby greatly increasing surface energy and chemical activity, providing an excellent adhesion foundation for subsequent metal layer deposition; 2) to form a modified layer on the surface by injecting specific ions (such as nitrogen ions), improving the dielectric properties of the substrate and helping to reduce dielectric loss; and 3) to achieve atomic-level surface cleaning, removing microscopic contaminants that are difficult to remove using traditional wet processing. This step fundamentally solves the problem of surface morphology damage caused by traditional roughening processes, achieving the goal of enhancing adhesion without increasing roughness.

[0013] (2) Magnetic Filtered Cathode Vacuum Arc (FCVA) Deposition Bonding and Seed Layer

[0014] On the surface of an ion-implanted modified substrate, an ultrathin metal bonding layer and a seed layer are deposited using FCVA technology.

[0015] The key advantage of MFCVA technology lies in its ability to generate highly ionized metal plasma and filter out "macro-particles" (droplets) that are common in traditional vacuum arc deposition and detrimental to film quality. When high-energy metal ions bombard the substrate surface (which can be further modulated by applying a substrate bias voltage), they produce an "injection effect" and "subsurface injection mixing," forming a gradient transition layer at the interface, thereby achieving a bonding strength far exceeding that of traditional PVD processes.

[0016] (3) High-power pulsed magnetron sputtering (HiPIMS) deposition of ultra-low profile initial conductor layer

[0017] On the seed layer prepared by FCVA, an initial copper conductor layer with a thickness of 0.5-2.0 μm was then deposited using HiPIMS technology. Compared with conventional DC magnetron sputtering, HiPIMS applies extremely high peak power within an extremely short pulse time, resulting in a very high ionization rate of copper atoms sputtered from the target. Guided by the substrate bias, these high-energy copper ions are densely deposited in a near-perpendicular incident manner, effectively suppressing the growth of "columnar crystals" and forming an extremely smooth and dense thin film structure.

[0018] (4) Pulse electroplating to thicken conductors

[0019] Since PVD processes have low efficiency in depositing thick films, this invention employs a pulsed electroplating process to thicken the initial conductive layer deposited by HiPIMS, forming the final desired conductive circuit. By precisely controlling the waveform, duty cycle, and frequency of the pulsed current, the electrocrystallization process of copper is controlled, preferentially filling microscopic depressions and suppressing the growth of protrusions. This allows for the thickening of the layer while maximally maintaining or even improving the low-profile characteristics established by the HiPIMS layer. Further strengthening the bonding between the plating layer and the seed layer can be achieved by optimizing electroplating parameters such as current density and temperature.

[0020] (5) Surface ion beam polishing

[0021] After electroplating, to achieve the ultimate surface smoothness, this invention introduces a final finishing process—ion beam polishing. This uses a wide-current, low-energy inert gas ion beam (such as Ar). +The ion beam uniformly "scans" or "mills" the conductor surface at a specific angle. This process, like atomic-level "sandpaper," precisely removes microscopic peaks and unevenness that may occur during electroplating without introducing any mechanical stress or subsurface damage. By precisely controlling the energy, current, and processing time of the ion beam, the surface roughness Rz of the conductor can be stably controlled below 0.6 μm, or even at the nanometer level, thereby minimizing the surface roughness effect of high-frequency signals.

[0022] Preferably, the polymer substrate in step (1) includes ABF, MPI, or BT;

[0023] The pretreatment includes: ultrasonically cleaning the polymer substrate with acetone, ethanol and deionized water sequentially for 10 min, followed by thorough drying for 10 h;

[0024] The ion types implanted include N+ or Ni+; the implantation energy is 5-15 kV; and the ion dose is 1 × 10⁻⁶. 15 -5×10 15 ions / cm².

[0025] Preferably, in step (2), the metal adhesive layer comprises Ti or Cr, and the seed layer comprises Cu;

[0026] The deposition parameters for the metal bonding layer include: arc current of 60-80 A, DC negative bias of 100-150 V, and deposition thickness of 15-30 nm.

[0027] The deposition parameters for the seed layer include: arc current of 80A, DC negative bias of -80V, and deposition thickness of 50nm.

[0028] Step (2) uses a magnetic filter pipe that is bent at 90 degrees.

[0029] Preferably, the power supply for pulsed magnetron sputtering deposition is set to: pulse frequency 300 Hz, pulse width 100 μs, and peak power density 2.5 kW / cm².

[0030] The pulse bias voltage is -60V;

[0031] The copper conductor layer has a deposition thickness of 1.0 μm.

[0032] Preferably, in the pulse electroplating process, the electroplating solution is a copper sulfate system;

[0033] Electroplating parameters: The anode is a phosphorus-containing copper ball, the average current density is 2.5 A / dm², the forward pulse width is 10 ms, the reverse pulse width is 1 ms, and the temperature is controlled at 30±2℃;

[0034] Preferably, in ion beam polishing, a Kaufman-type wide-current ion source is used, and the ion type is argon ions (Ar+).

[0035] Polishing parameters: Ion energy set to 600-800 eV, beam current density to 0.5 mA / cm².

[0036] The present invention also proposes an integrated system for implementing the above methods. The system integrates multiple functional modules such as ion implantation, FCVA, HiPIMS and ion beam polishing in a unified vacuum environment. The system realizes the transfer of workpieces between different workstations through a central control system and a vacuum transfer robotic arm, which ensures the cleanliness, stability and production efficiency of the process.

[0037] As can be seen from the above technical solution, compared with the prior art, the present invention has the following beneficial effects:

[0038] 1. Ultra-low insertion loss: Through the dual action of ion beam deposition and polishing, conductor lines with an extremely smooth surface are manufactured, which significantly reduces conductor loss in the millimeter wave band. Combined with the improvement of dielectric properties by ion implantation, the insertion loss in the 50-60GHz band can be stably controlled at -1.1dB / inch or lower, which is comparable to or even exceeds the international leading technical indicators.

[0039] 2. Ultra-low surface profile: This invention abandons the traditional substrate roughening process. From ion implantation modification and HiPIMS film formation to ion beam polishing, the entire process is precisely controlled for surface flatness, ultimately achieving an ultra-low profile of Rz ≤ 0.65μm, which provides an ideal physical basis for low-distortion transmission of high-frequency signals.

[0040] 3. Ultra-high bonding strength: Through the synergistic effect of ion implantation pretreatment and FCVA deposition gradient interface layer, an atomic-level strong bond is achieved between the metal conductor layer and the polymer substrate. The bonding strength can stably reach more than 0.5 N / mm, which is far higher than that of traditional processes, ensuring the long-term reliability of the product in harsh application environments.

[0041] 4. Process integration and synergistic advantages: This invention creatively integrates multiple advanced ion beam technologies in a series, with each process step creating optimal conditions for achieving the next goal, forming a synergistic enhancement effect of "1+1>2", which is a systematic innovation that cannot be matched by existing single-point technology improvements.

[0042] 5. Wide applicability of materials: The method proposed in this invention is not only applicable to ABF, but can also be extended to various mainstream and next-generation high-frequency and high-speed electronic substrates such as MPI and BT, and has strong prospects for industrial application. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0044] Figure 1 (a) shows the interface morphology of the copper substrate in Example 1, and (b) shows the interface morphology of the hot-pressed copper substrate.

[0045] Figure 2 This is a flowchart illustrating the preparation process of the present invention.

[0046] Figure 3 Schematic diagram of an integrated ion beam system;

[0047] In the diagram: 301 - MEVVA ion implantation, 302 - HiPIMS, 303 - FCVA, 304 - Kaufman ion beam polishing system, 305 - mechanical transmission device. Detailed Implementation

[0048] 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 some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] Example 1: For ABF substrate

[0050] 1. Substrate pretreatment and ion implantation modification

[0051] The cut ABF substrate sheet is placed into the ion implantation module of the vacuum system. The vacuum level is evacuated to 5×10⁻⁶. -4 Below Pa. Ion type injected: Nitrogen ion (N...) + Nitrogen ion implantation not only enhances surface activity but also forms a nitrogen-rich, hard modified layer on the surface, which is beneficial for improving the adhesion of subsequent films. Implantation energy: 12 keV. This energy ensures that ions form a modified layer at a depth of tens of nanometers below the ABF surface, effectively without excessively damaging the substrate (reference energy range. Ion dose: 2 × 10⁻⁶). 15 ions / cm². This dosage is sufficient to form a high density of active sites on the surface. After treatment, the substrate is transported to the next station via a vacuum transfer system.

[0052] 2. FCVA deposition of Ti / Cu binder and seed layer

[0053] The workpiece enters the FCVA deposition module, and the vacuum level is maintained at 1×10⁻⁶. -3 Pa.

[0054] First layer (adhesive layer): A titanium (Ti) target with a purity of 99.99% was used. An arc current of 60A was set, and a DC negative bias of -150V was applied to the substrate to increase the bombardment energy of the titanium ions and promote the formation of the interfacial hybrid layer. The deposition thickness was 20nm.

[0055] The second layer (seed layer): Switch to a copper (Cu) target with a purity of 99.999%. The arc current is adjusted to 80A, and the substrate bias voltage is reduced to -80V to facilitate the formation of well-crystallized copper seed crystals. The deposition thickness is 50 nm. The entire process utilizes a 90-degree curved magnetic filter channel to effectively filter out large particles.

[0056] 3. HiPIMS deposition of ultra-low profile copper conductor layer

[0057] The workpiece enters the HiPIMS deposition module, and 99.999% pure argon gas is introduced as the working gas, with the pressure controlled at 0.5 Pa. A 99.999% pure copper target is used. The HiPIMS power supply is set to: pulse frequency 300 Hz, pulse width 100 μs, and peak power density reaching 2.5 kW / cm². These parameters ensure a high ionization rate of copper atoms. A -60V synchronous pulse bias is applied to the substrate to attract high-energy copper ions to bombard the surface perpendicularly, promoting the growth of a dense film. An initial copper conductor layer with a thickness of 1.0 μm is deposited. Atomic force microscopy (AFM) measurements show that the root mean square (Rq) surface roughness of this copper layer is less than 5 nm.

[0058] 4. Pulse electroplating thickening

[0059] The PVD-treated substrate was removed from the vacuum system and placed in a pulse electroplating bath. The electroplating solution was a copper sulfate system. Electroplating parameters: the anode was a phosphorus-containing copper ball; the average current density was 2.5 A / dm²; the forward pulse width was 10 ms; the reverse pulse width was 1 ms; and the temperature was controlled at 30±2℃. Electroplating was carried out until the total copper thickness reached 2 μm.

[0060] 5. Surface ion beam polishing

[0061] The workpiece is then fed back into the ion beam polishing module of the vacuum system. A Kaufman wide-current ion source is used, with argon ions (Ar) as the ion type. +Polishing parameters: Ion energy set to 800 eV, beam current density 0.5 mA / cm². The ion beam scans the copper surface at a grazing incidence angle of 75 degrees. Polishing time is precisely controlled, aiming to remove approximately 60 nm of material from the surface to eliminate the microscopic roughness of the outermost layer of the electroplated layer.

[0062] Performance test results:

[0063] Insertion loss: The fabricated microstrip line was tested at 56 GHz using a vector network analyzer (VNA) and a high-frequency probe station. The insertion loss was measured to be -0.95 dB / inch. This is attributed to the extremely smooth surface achieved by ion beam polishing and the overall low profile structure.

[0064] Surface roughness: The final conductor surface was measured using a 3D profilometer or AFM, and the Rz value was found to be 0.52 μm.

[0065] Bond strength: The tensile peel test was performed according to the IPC-TM-650 standard. The measured bond strength between the copper conductor layer and the ABF substrate was 0.6 N / mm.

[0066] Example 2: For MPI film

[0067] 1. Substrate pretreatment and ion implantation modification

[0068] The cut MPI substrate sheet is placed into the ion implantation module of the vacuum system. The vacuum level is evacuated to 5×10⁻⁶. -4 Below Pa. Ion type: Nickel ions (Ni + Nickel ion implantation not only enhances surface activity but also forms a chelate network on the subsurface, which is beneficial for improving the adhesion of subsequent films. Implantation energy: 7 keV. This energy ensures that ions form a modified layer at a depth of several nanometers below the ABF surface, effectively without excessively damaging the substrate (reference energy range. Ion dose: 3 × 10⁻⁶). 15 ions / cm². This dosage is sufficient to form a high density of active sites on the surface. After treatment, the substrate is transported to the next station via a vacuum transfer system.

[0069] 2. FCVA deposition of Cr / Cu binder and seed layer

[0070] The workpiece enters the FCVA deposition module, where the vacuum level is maintained at 1×10⁻³ Pa.

[0071] First layer (adhesive layer): A chromium (Cr) target with a purity of 99.99% was used. An arc current of 75A was set, and a DC negative bias of -100V was applied to the substrate to increase the bombardment energy of the chromium ions and promote the formation of the interfacial mixed layer. The deposition thickness was 20nm.

[0072] The second layer (seed layer): Switch to a copper (Cu) target with a purity of 99.999%. The arc current is adjusted to 80A, and the substrate bias voltage is reduced to -80V to facilitate the formation of well-crystallized copper seed crystals. The deposition thickness is 50 nm. The entire process utilizes a 90-degree curved magnetic filter channel to effectively filter out large particles.

[0073] 3. HiPIMS deposition of ultra-low profile copper conductor layer

[0074] The workpiece enters the HiPIMS deposition module, and 99.999% pure argon gas is introduced as the working gas, with the pressure controlled at 0.5 Pa. A 99.999% pure copper target is used. The HiPIMS power supply is set to: pulse frequency 300 Hz, pulse width 100 μs, and peak power density reaching 2.5 kW / cm². These parameters ensure a high ionization rate of copper atoms. A -60V synchronous pulse bias is applied to the substrate to attract high-energy copper ions to bombard the surface perpendicularly, promoting the growth of a dense film. An initial copper conductor layer with a thickness of 1.0 μm is deposited. Atomic force microscopy (AFM) measurements show that the root mean square (Rq) surface roughness of this copper layer is less than 5 nm.

[0075] 4. Pulse electroplating thickening

[0076] The PVD-treated substrate was removed from the vacuum system and placed in a pulse electroplating bath. The electroplating solution was a copper sulfate system. Electroplating parameters: the anode was a phosphorus-containing copper ball; the average current density was 2.5 A / dm²; the forward pulse width was 10 ms; the reverse pulse width was 1 ms; and the temperature was controlled at 30±2℃. Electroplating was carried out until the total copper thickness reached 2 μm.

[0077] 5. Surface ion beam polishing

[0078] The workpiece is then fed back into the ion beam polishing module of the vacuum system. A Kaufman wide-current ion source is used, with argon ions (Ar) as the ion type. + Polishing parameters: Ion energy set to 600 eV, beam current density 0.5 mA / cm². The ion beam scans the copper surface at a grazing incidence angle of 75 degrees. Polishing time is precisely controlled, aiming to remove approximately 50 nm of material from the surface to eliminate the microscopic roughness of the outermost layer of the electroplated layer.

[0079] Performance test results:

[0080] Insertion loss: The fabricated microstrip line was tested at 56 GHz using a vector network analyzer (VNA) and a high-frequency probe station. The insertion loss was measured to be -1.05 dB / inch. This is attributed to the extremely smooth surface achieved by ion beam polishing and the overall low profile structure.

[0081] Surface roughness: The final conductor surface was measured using a 3D profilometer or AFM, and the Rz value was found to be 0.55 μm.

[0082] Bond strength: The tensile peel test was performed according to the IPC-TM-650 standard. The measured bond strength between the copper conductor layer and the MPI substrate was 0.7 N / mm.

[0083] Example 3: For BT substrates

[0084] 1. Substrate pretreatment and ion implantation modification

[0085] The cut BT substrate sheet is placed into the ion implantation module of the vacuum system. The vacuum level is evacuated to 5×10⁻⁶. -4 Below Pa. Ion type injected: Nitrogen ion (N...) + Nitrogen ion implantation not only enhances surface activity but also forms a nitrogen-rich, hard modified layer on the surface, which is beneficial for improving the adhesion of subsequent films. Implantation energy: 15 keV. This energy ensures that ions form a modified layer at a depth of tens of nanometers below the BT surface, effectively without excessively damaging the substrate (reference energy range. Ion dose: 5 × 10⁻⁶). 15 ions / cm². This dosage is sufficient to form a high density of active sites on the surface. After treatment, the substrate is transported to the next station via a vacuum transfer system.

[0086] 2. FCVA deposition of Ti / Cu binder and seed layer

[0087] The workpiece enters the FCVA deposition module, where the vacuum level is maintained at 1×10⁻³ Pa.

[0088] First layer (adhesive layer): A titanium (Ti) target with a purity of 99.99% was used. An arc current of 80A was set, and a DC negative bias of -150V was applied to the substrate to increase the bombardment energy of chromium ions and promote the formation of the interfacial mixed layer. The deposition thickness was 30nm.

[0089] The second layer (seed layer): Switch to a copper (Cu) target with a purity of 99.999%. The arc current is adjusted to 80A, and the substrate bias voltage is reduced to -80V to facilitate the formation of well-crystallized copper seed crystals. The deposition thickness is 80 nm. The entire process utilizes a 90-degree curved magnetic filter channel to effectively filter out large particles.

[0090] 3. HiPIMS deposition of ultra-low profile copper conductor layer

[0091] The workpiece enters the HiPIMS deposition module, and 99.999% pure argon gas is introduced as the working gas, with the pressure controlled at 0.5 Pa. A 99.999% pure copper target is used. The HiPIMS power supply is set to: pulse frequency 300 Hz, pulse width 100 μs, and peak power density reaching 2.5 kW / cm². These parameters ensure a high ionization rate of copper atoms. A -60V synchronous pulse bias is applied to the substrate to attract high-energy copper ions to bombard the surface perpendicularly, promoting the growth of a dense film. An initial copper conductor layer with a thickness of 1.0 μm is deposited. The root mean square (Rq) surface roughness of this copper layer is less than 5 nm, as measured by atomic force microscopy (AFM).

[0092] 4. Pulse electroplating thickening

[0093] The PVD-treated substrate was removed from the vacuum system and placed in a pulse electroplating bath. The electroplating solution was a copper sulfate system. Electroplating parameters: the anode was a phosphorus-containing copper ball; the average current density was 2.5 A / dm²; the forward pulse width was 10 ms; the reverse pulse width was 1 ms; and the temperature was controlled at 30±2℃. Electroplating was carried out until the total copper thickness reached 3 μm.

[0094] 5. Surface ion beam polishing

[0095] The workpiece is then fed back into the ion beam polishing module of the vacuum system. A Kaufman wide-current ion source is used, with argon ions (Ar) as the ion type. + Polishing parameters: Ion energy set to 800 eV, beam current density 0.5 mA / cm². The ion beam scans the copper surface at an 80-degree grazing incidence angle. Polishing time is precisely controlled, aiming to remove approximately 100 nm of material from the surface to eliminate the microscopic roughness of the outermost layer of the electroplated layer.

[0096] Performance test results:

[0097] Insertion loss: The fabricated microstrip line was tested at 56 GHz using a vector network analyzer (VNA) and a high-frequency probe station. The insertion loss was measured to be -1.06 dB / inch. This is attributed to the extremely smooth surface achieved by ion beam polishing and the overall low profile structure.

[0098] Surface roughness: The final conductor surface was measured using a 3D profilometer or AFM, and the Rz value was found to be 0.6 μm.

[0099] Bond strength: The tensile peel test was performed according to the IPC-TM-650 standard. The measured bond strength between the copper conductor layer and the MPI substrate was 0.74 N / mm.

[0100] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0101] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for ion beam recombination control of high-frequency, high-speed electronic substrates for AI, characterized in that, Includes the following steps: (1) Surface modification of substrate by ion implantation Before metallization, the polymer substrate is pretreated by ion implantation, which uses a high-energy ion beam to bombard the substrate surface. (2) Magnetic filter cathode vacuum arc deposition bonding and seed layer On the surface of the substrate modified by ion implantation, an ultrathin metal bonding layer and a seed layer are deposited using magnetically filtered cathode vacuum arc technology. (3) High-power pulsed magnetron sputtering deposition of ultra-low profile initial conductor layer On the seed layer, an initial copper conductor layer with a thickness of 0.5-2.0 μm is then deposited using high-power pulsed magnetron sputtering technology; (4) Pulse electroplating to thicken conductors The initial copper conductor layer is thickened using a pulse electroplating process to form the final required conductive circuit. (5) Surface ion beam polishing After electroplating, the surface roughness Rz of the conductor is stably controlled below 0.6 μm by scanning or milling with an inert gas ion beam.

2. The ion beam recombination control method for AI high-frequency and high-speed electronic substrates according to claim 1, characterized in that, The polymer substrate mentioned in step (1) includes ABF, MPI, or BT; The pretreatment includes: ultrasonically cleaning the polymer substrate with acetone, ethanol and deionized water sequentially for 10 min, followed by thorough drying for 10 h; The ion types implanted include: N + or Ni + The injection energy is 5-15 kV; the ion dose is 1 × 10⁻⁶. 15 -5×10 15 ions / cm².

3. The ion beam recombination control method for AI high-frequency and high-speed electronic substrates according to claim 1, characterized in that, In step (2), the metal adhesive layer includes Ti or Cr, and the seed layer includes Cu; The deposition parameters for the metal bonding layer include: arc current of 60-80 A, DC negative bias of 100-150 V, and deposition thickness of 15-30 nm. The deposition parameters for the seed layer include: arc current of 80A, DC negative bias of -80V, and deposition thickness of 50nm. Step (2) uses a magnetic filter pipe that is bent at 90 degrees.

4. The ion beam recombination control method for AI high-frequency and high-speed electronic substrates according to claim 1, characterized in that, The power supply settings for pulsed magnetron sputtering deposition were: pulse frequency 300 Hz, pulse width 100 μs, and peak power density 2.5 kW / cm². The pulse bias voltage is -60V; The copper conductor layer has a deposition thickness of 1.0 μm.

5. The ion beam recombination control method for AI high-frequency and high-speed electronic substrates according to claim 1, characterized in that, In the pulse electroplating process, the electroplating solution is a copper sulfate system; Electroplating parameters: The anode is a phosphorus-containing copper ball, the average current density is 2.5 A / dm², the forward pulse width is 10 ms, the reverse pulse width is 1 ms, and the temperature is controlled at 30±2℃.

6. The ion beam recombination control method for AI high-frequency and high-speed electronic substrates according to claim 1, characterized in that, In ion beam polishing, a Kaufman-type wide-current ion source is used, with argon ions (Ar) as the ion type. + ); Polishing parameters: Ion energy set to 600-800 eV, beam current density to 0.5 mA / cm².

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