Manufacturing process of printed circuit of high-density circuit board

Abstract

The invention relates to the technical field of printed circuit manufacturing, and discloses a manufacturing process of a high-density circuit board printed circuit, which comprises the following steps of: coating organosilane bridging molecules with polydentate coordination functional groups on the surface of an insulating base material to form a self-assembled chemical anchoring layer; laser energy field graphical scanning is utilized to establish a silicon-oxygen covalent bond in a scanned area, and a graphical activation area is constructed; applying an external cleaning energy field of which the action energy level is between physical adsorption energy and chemical bond energy, and removing residual molecules in a non-scanning area; catalytic metal ions are introduced into the pattern active region, and a chelating center is established by using a polydentate coordination functional group so as to lock a nucleation site; according to the method, atomic-scale surface purification is achieved through a bond energy differentiation response mechanism, the potential electromigration hazard of a non-operation area is eliminated, metal nucleation displacement is limited through cooperation of a chelating structure, the problem of edge blurring of a superfine circuit is solved, and the thermal mechanical robustness of the circuit is improved.

Description

Technical Field

[0001] This invention relates to a manufacturing process for high-density printed circuit boards, belonging to the field of printed circuit manufacturing technology. Background Technology

[0002] Currently, the high-density circuit board manufacturing industry generally adopts the full addition process, which utilizes self-assembled monolayers to construct chemical anchoring interfaces on the substrate surface. By activating the target area through a specific energy field, metal atoms are induced to nucleate in a directional manner and achieve anisotropic growth, thereby restoring the circuit pattern. When the wiring spacing evolves to below 10μm, the system faces the constraints of the evolution of interface physical properties. In non-operating areas, under the influence of van der Waals forces and capillary forces, trace amounts of bridging molecules or catalytic metal ions produce random physical residues. These metastable residues induce ion electromigration in the operating environment, leading to a decrease in insulation reliability. At the same time, in the microchannel deposition stage, the confinement effect causes the metal ion consumption rate to exceed the external diffusion replenishment rate, forming a dynamic ion depletion layer at the interface, resulting in uneven conductor density.

[0003] Conventional optimization approaches typically attempt to increase physical cleaning pressure or enhance chemical circulation intensity. However, simply increasing the physical scouring kinetic energy can easily damage the already bonded chemical functional layers, causing pattern boundary breakage. Furthermore, methods such as increasing additive concentration are limited by the spatial scale of micron-level deep trenches and cannot solve quality defects caused by diffusion limitations. There is a fundamental constraint that is difficult to reconcile between pursuing wiring precision and ensuring long-term service reliability. For example, Chinese invention patent CN120962098A discloses a method, device, system, equipment, and medium for laser patterning of photovoltaic cell films, establishing a mapping relationship between film thickness and laser power, and adjusting... The processing energy achieves deep uniformity. This scheme is based on a thickness-power mapping compensation mechanism. The underlying logic remains at the overall energy superposition fitting, without addressing the conflict between atomic-level purification and selective stripping in high-density circuit manufacturing. Because the geometric scales of physically adsorbed impurities and target anchored molecules highly overlap and the thickness difference is slight, the thickness compensation feedback mechanism cannot identify the surface differences of molecular binding energy levels. It is difficult to establish logic gates for chemical bond energy levels at the interface and cannot eliminate pseudo-nucleation burrs induced by metastable residues. In addition, this type of method lacks systematic control over mass transfer imbalance and thermal cycling stress mismatch in microchannels, making it difficult to meet the requirements of conductor structure homogenization and reliability under high-frequency signals.

[0004] Therefore, how to establish a growth mechanism that can achieve bond level logic purification and coordinated mass transfer self-balancing is the technical problem to be solved by this invention. Summary of the Invention

[0005] To address the problems mentioned in the background art, the technical solution of the present invention is as follows: A manufacturing process for high-density printed circuit boards, comprising the following steps:

[0006] Step S101: A self-assembled chemical anchoring layer is formed on the surface of the insulating substrate. The self-assembled chemical anchoring layer is composed of organosilane bridging molecules with multidentate coordination functional groups.

[0007] Step S102: The self-assembled chemical anchoring layer is patterned by using a laser energy field to establish covalent bonds between the organosilane bridging molecules in the scanned area and the surface of the insulating substrate to form a patterned activation region, while maintaining the physical adsorption state residue of the organosilane bridging molecules in the non-scanned area.

[0008] Step S103: Perform energy level difference cleaning, apply an external cleaning energy field, and adjust the output power of the external cleaning energy field so that the energy density of the external cleaning energy field acting on the surface of the insulating substrate is higher than the physical adsorption energy threshold of the physically adsorbed residue and lower than the chemical bond energy threshold of the covalent bond, so as to remove the physically adsorbed residue in the non-scanning area.

[0009] Step S104: Introduce catalytic metal ions into the pattern activation region after energy level difference cleaning, and use multidentate coordination functional groups to establish chelation centers to fix the catalytic metal ions and limit the initial nucleation displacement of the catalytic metal ions.

[0010] In step S105, chemical deposition is performed in the pattern activation area to orient conductive metal atoms for nucleation and growth along the self-assembled chemical anchoring layer to restore the circuit pattern. In step S103, the surface contact angle parameters of the non-scanning area are monitored in real time using an online optical monitoring unit. The online optical monitoring unit includes a micro-spraying module and a high-speed imaging sampling module. The high-speed imaging sampling module captures the profile of the probe droplet under stroboscopic illumination and analyzes the surface contact angle parameters in real time. Based on the deviation between the surface contact angle parameters and the contact angle reference value preset based on the properties of the insulating substrate, the power output parameters of the external cleaning energy field are dynamically adjusted through closed-loop feedback control logic until the surface contact angle parameters reach the contact angle reference value.

[0011] Preferably, after performing energy level difference cleaning, the method further includes adjusting the interface stress of the pattern activation area: acquiring electrical signals through a flexible pressure sensor array integrated on the back of the insulating substrate to monitor the interface shear stress between the conductive metal atoms and the insulating substrate in real time, and using the flexible chain segments of organosilane bridging molecules to generate displacement deformation in response to the interface shear stress, so as to dissipate the residual stress caused by the mismatch of thermal expansion coefficients and avoid the edge peeling of the circuit pattern.

[0012] Preferably, in step S105, closed-loop control of liquid film thickness is performed: a piezoelectric pressure sensor installed on the wall of the chemical deposition tank is used to monitor the hydrodynamic pressure parameters at the interface between the pattern activation zone and the chemical copper plating solution, the diffusion boundary layer thickness is calculated based on the hydrodynamic pressure parameters, and the circulation flow rate of the chemical copper plating solution is adjusted according to the offset of the diffusion boundary layer thickness relative to the target thickness to compensate for the diffusion flux of organosilane bridging molecules.

[0013] Preferably, the organosilane bridging molecule comprises a silane coupling agent containing at least one polydentate coordination functional group selected from sulfur, amino, and carboxyl groups; the organosilane bridging molecule in the patterned activation region is connected to the surface of the insulating substrate via... Covalent bonds.

[0014] Preferably, step S103 specifically includes: adjusting the cleaning medium. The charge is equal to the isoelectric point of the organosilane bridging molecules. The electrostatic repulsion after charge neutralization, combined with the mechanical scouring kinetic energy, destroys the physically adsorbed residues in the non-scanning region.

[0015] Preferably, the organosilane bridging molecule also has a hydrogen ion-sensitive functional group; the growth in step S105 includes wiring width control: in the lateral growth direction of the circuit pattern, by changing the local area The value drives the hydrogen ion-sensitive functional groups to generate charge flipping, thereby physically shielding the catalytic sites in the lateral growth direction.

[0016] Preferably, during chemical deposition, the metal ion concentration in the microchannels within the patterned activation region is monitored; when the metal ion concentration falls below a preset concentration threshold, the reaction temperature of the chemical deposition is reduced to [value missing]. to Between these, the nucleation rate is slowed down and the interfacial ion depletion phenomenon is eliminated.

[0017] Preferably, the external cleaning energy field is composed of a combination of an ultrasonic cavitation field and a pulsed laser thermal field; by adjusting the pulse width of the pulsed laser thermal field, the instantaneous temperature gradient on the surface of the non-scanning area is controlled, so that the molecular kinetic energy of the physically adsorbed residue exceeds the physical adsorption energy threshold.

[0018] Preferably, energy level difference cleaning satisfies the following energy constraint rules: ,in, The physical adsorption energy is the adsorption energy of physically adsorbed residues on the surface of the insulating substrate. The chemical bond energy of the covalent bonds within the activated region of the pattern. The cleaning energy level is the cleaning energy level applied to the surface of the insulating substrate by an external cleaning energy field; and All parameters are fixed parameters that were pre-determined based on the material properties of the organosilane bridging molecules and the insulating substrate.

[0019] Preferably, the manufacturing process is used to produce wiring with a spacing of less than [specified value]. The printed circuit board; conductive metal atoms including copper, nickel or gold atoms; after chemical deposition, the process also includes removing the self-assembled chemical anchoring layer exposed outside the circuit pattern using a plasma bombardment process.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] 1. In high-density printed circuit boards (PCBs), the manufacturing process of high-density PCBs, through the synergistic effect of multiple mechanisms, has achieved a fundamental leap in wiring accuracy and reliability while improving process stability. A selective resolution mechanism based on chemical potential gradient switching has been constructed. Utilizing the order-of-magnitude difference in binding energy between the covalent bonding energy of the active region and the physical adsorption energy of the non-active region, the elution medium, under the action of a cavitation energy field at a specific frequency, precisely controls the interfacial physical interaction energy within the band gap between the physical adsorption energy and the covalent bond energy. This logical discrimination method of energy levels causes illegally residing molecules to spontaneously desorb under kinetic energy impact, while the molecular anchors in the patterned region maintain structural integrity in a deep potential well state. This eliminates background noise and avoids pseudo-nucleation burrs induced by metastable impurities, thus achieving a substantial breakthrough in wiring densification boundaries without relying on improving laser resolution.

[0022] 2. The mass transfer imbalance in deep trenches is solved by using a time-space decoupled pulse growth logic. Asymmetric square wave pulse current is used to separate the electrochemical deposition of metal atoms from the mass transfer of ions on the time axis. During the repair phase when the current is zero, the natural diffusion relaxation characteristics of metal ions are used to spontaneously flatten the ion concentration gradient in the channel. This alternation of growth phase and relaxation phase eliminates the ion depletion layer at the growth interface, making the lattice arrangement of the conductor structure tend to be ideal and ordered. While achieving full density evolution, it breaks through the constraints of hydrodynamics on the aspect ratio of ultra-fine lines and reduces the high-frequency signal dispersion effect caused by structural defects.

[0023] 3. An interfacial thermal stress self-adaptation mechanism based on surface conformational reversal is introduced. By constructing a hybrid grafting topology composed of molecules with different chain lengths inside the anchoring layer, long-chain molecules rearrange their chain segments using changes in molecular entropy when they undergo displacement under heat, providing nanoscale lateral displacement compensation for the metal conductor. This non-dense grafting structure with surface degrees of freedom serves as a thermodynamic compensation unit at the molecular scale, effectively dissipating the shear stress between the metal conductor and the insulating substrate, and avoiding early stripping of the circuit due to expansion coefficient mismatch. In addition, by combining functional groups with hydrogen ion-sensitive properties, the system physically shields catalytic active sites in the lateral growth direction through charge state reversal triggered by local pH abrupt changes, achieving logic self-limitation of wiring resolution. Attached Figure Description

[0024] Figure 1 This is a flowchart illustrating the entire manufacturing process of the high-density circuit board self-assembly anchoring and energy level difference cleaning of the present invention.

[0025] Figure 2 This is a schematic diagram of the ion concentration monitoring and reaction rate closed-loop control logic during the chemical deposition process of this invention. Detailed Implementation

[0026] The technical solution provided by the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The following embodiments are intended to explain the present invention and are not intended to limit the scope of protection of the present invention.

[0027] This invention provides a manufacturing process for high-density printed circuit boards. By constructing a self-assembled chemical anchoring layer with a chemical potential energy gradient on the surface of an insulating substrate, and utilizing the energy level difference between the excited covalent bonding energy and the physical adsorption energy of the non-working area to perform logical cleaning, the process achieves directional nucleation and anisotropic growth of conductive metal atoms at the nanoscale without the need for traditional resist masks. The process encompasses key stages such as the construction of the self-assembled anchoring layer, laser patterning scanning, energy level difference cleaning, catalytic site locking, and metal thickening deposition. Atomic-level reduction of the circuit pattern is achieved through fluid interface control and energy field matching. In the step of forming the self-assembled chemical anchoring layer on the insulating substrate surface, a silane coupling agent containing at least one multidentate coordination functional group selected from sulfur, amino, and carboxyl groups is used as an organosilane bridging molecule. The organosilane bridging molecule is formulated to a mass fraction of [missing information]. to The grafting solution utilizes the self-assembly properties of silane molecules to form a dense monolayer on the substrate surface. Its multidentate coordination functional groups are used to subsequently establish chelation centers to lock metal catalytic sites. When the insulating substrate enters the grafting flow field, by controlling the liquid exit velocity and angle, and using interfacial tension gradient induction, the grafting solution spontaneously forms a local liquid film distribution matching the circuit pattern under the guidance of the high surface energy characteristics of the patterned activation region, thereby compensating for differences in chemical potential energy distribution on the substrate surface. A laser energy field is used to perform patterned scanning of the self-assembled chemical anchoring layer. The pulsed laser is controlled to move across the surface of the self-assembled chemical anchoring layer according to the circuit design trajectory, allowing the organosilane bridging molecules in the scanned area to connect with the insulating substrate surface via... Covalent bonds establish chemical bonds, thereby forming patterned active regions; in the non-scanning regions not irradiated by the laser, organosilanes bridging molecules remain in a physically adsorbed state as residues; this difference in chemical bonding based on laser-induced induced bonding provides an energy threshold basis for selective stripping, resulting in a binding energy difference across orders of magnitude between the patterned active regions and the non-scanning regions.

[0028] To eliminate line spacing lower than Due to the potential electromigration induced by physical residues, the process employs an energy level difference cleaning procedure; this procedure complies with energy constraint rules. ,in, The physical adsorption energy of the physically adsorbed residue on the surface of the insulating substrate is [value missing]. to interval, The chemical bond energy of the covalent bonds within the activated region of the diagram is [value missing]. to Within the range, The cleaning energy level is the cleaning energy level applied to the surface of the insulating substrate by an external cleaning energy field; by adjusting the output power of the external cleaning energy field, the physical adsorption energy... With chemical bond energy The energy levels of the external cleaning energy field were obtained by single-molecule force spectroscopy measurements of amino-terminated silane molecules and the dielectric substrate. Adjust the infrared pulsed laser between 10 and 50 The pulse width controls the instantaneous temperature gradient on the surface, generating molecular desorption kinetic energy. The surface purification state in the non-scanning area is determined by the static water contact angle. Verification was performed by increasing the output sound intensity of the ultrasonic cavitation field, thus... Reference value of contact angle with substrate body The absolute value of the difference is less than 1.0 Graphical activation area The covalent bond structure is removed without damage to physically adsorbed residues, thus enabling the cleaning energy level to be optimized. The physical experimental platform, which integrates a contact angle measurement unit and a pulse energy control unit, is specifically manifested in industrial applications as an online closed-loop controlled system integrated above the production line guide rail. The micro-volume spraying module of the online optical monitoring unit uses piezoelectric inkjet technology to spray detection water droplets with a volume of 0.5nL to 2.0nL onto the non-scanning area. The sampling frequency of the high-speed imaging sampling module is synchronized with the production line speed, and its spatial resolution is set to be no less than 5μm / pixel. The image motion caused by the substrate movement is offset by a stroboscopic light source. To achieve dynamic power adjustment, the system executes the following closed-loop control algorithm: ,in, The real-time output power of the external cleaning energy field at time t; The baseline cleaning power is set based on the initial material processing. The power response gain coefficient is preset based on the thermal damage threshold of the insulating substrate, and its value ranges from 0.1 to 0.5 W / °. The following calibration procedures are used to obtain the following data: Before formal production, a three-dimensional mapping matrix of residual concentration, contact angle, and cleaning power is established under static conditions for a specific insulating substrate and selected organosilane bridging molecules. The results are then determined using least squares fitting to determine the appropriate parameters under the current environment. Initial value; This is the preset contact angle reference value; The algorithm logic ensures that when online monitoring detects physical adsorption residues in the non-scanning area, the system automatically increases the cleaning energy level, thus achieving atomic-level purification at the production line level without relying on a specific single model of equipment. The quantitative determination procedure for the external cleaning energy field level is as follows: Obtain the output power (watts) of the infrared pulsed laser and divide it by the product of the laser pulse frequency and the laser spot area to obtain the energy density (joules per square centimeter) of a single pulse; multiply this energy density by the energy absorption coefficient of the insulating substrate surface, obtained by spectrophotometry on a blank substrate of the same material; finally, based on the physical constant relationship between Planck's constant and the speed of light, map the absorbed energy per unit area to the average electron volt value obtained by a single molecule, ensuring that the cleaning energy level is precisely within the median value of the 0.1 to 0.5 electron volt and 2 to 5 electron volt ranges. The external cleaning energy field is composed of an ultrasonic cavitation field and a pulsed laser thermal field; by adjusting the pulse width of the pulsed laser thermal field, the instantaneous temperature gradient on the surface of the non-scanning area is controlled, causing the molecular kinetic energy of the physically adsorbed residues to exceed the physical adsorption energy threshold. And below the chemical bond energy threshold At the same time, adjust the cleaning medium. The charge is brought to the isoelectric point of the organosilane bridging molecules, and the electrostatic repulsion after charge neutralization, combined with mechanical scouring kinetic energy, is used to peel off the residual molecules in the non-scanning area. During this period, the surface contact angle parameters of the non-scanning area are monitored in real time, and the energy field power is adjusted according to the deviation of the parameter from the preset contact angle reference value until the surface contact angle reaches the reference value.

[0029] Catalytic metal ions are introduced into the cleaned patterned activation region, and chelation centers are established using the multidentate coordination functional groups in the organosilane bridging molecules. Multiple coordinating atoms simultaneously act on a single metal ion to establish a cooperative chelation potential well, limiting the initial nucleation displacement of the catalytic metal ion. Chemical deposition is performed in the patterned activation region to allow conductive metal atoms to nucleate and grow in a directional manner. During chemical deposition, the hydrodynamic pressure parameters at the interface between the patterned activation region and the chemical copper plating solution are monitored, the diffusion boundary layer thickness is calculated, and the circulation flow rate of the chemical copper plating solution is adjusted based on the offset of this thickness relative to the target thickness to compensate for the diffusion flux of the organosilane bridging molecules. The hydrodynamic pressure parameters are... Based on the mapping model between the external circulation pump output frequency and the supply manifold system pressure, during the chemical deposition calibration stage, for specific aspect ratio microchannels, the parameters are determined within the range of 0.5 to 2.5. The flow velocity range records the backflow pressure, generating a pressure-flow velocity baseline curve, and the diffusion boundary layer thickness. Based on static fluid pressure reference value Compared with real-time measured values Difference calculation, proportionality coefficient The viscosity is determined by the isothermal kinematic viscosity of the chemical copper plating solution. More than 15 At that time, with 2 Step-increase variable frequency pump output frequency, at 10 The following confined space maintains the supply of metal ions. When the metal ion concentration in the microchannels within the patterned activation region is detected to be lower than a preset concentration threshold, the reaction temperature is reduced to... to Between these, the nucleation rate is slowed down and the interfacial ion depletion phenomenon is eliminated.

[0030] To address the residual stress caused by the mismatch in thermal expansion coefficients between the metal conductor and the insulating substrate, the process involves adjusting the interfacial stress in the patterned activation region after energy level difference cleaning. Real-time monitoring of the interfacial shear stress between the conductive metal atoms and the insulating substrate is employed, utilizing a hybrid grafted topology composed of molecules with different chain segment lengths to generate displacement deformation. In this invention, real-time monitoring of the interfacial shear stress is accomplished by a flexible piezoelectric thin-film sensor array embedded in the back of the insulating substrate. This sensor detects the lattice expansion force during metal layer growth and converts it into a millivolt-level electrical signal. Simultaneously, during chemical deposition, the diffusion boundary layer thickness is monitored. The calculation logic is corrected as follows: In this formula, The calculated diffusion boundary layer thickness is expressed in micrometers (µm). ); These are the structural constants determined by the geometry of the sedimentation tank channel; The dynamic viscosity of the chemical copper plating solution at the current reaction temperature; Let be the diffusion coefficient of metal ions in the deposition solution; where the parameter is... , and All of these are based on the current concentration ratio of the chemical copper plating solution and the physical specifications of the tank, which are pre-stored in the calibration database of the control unit. The measured value of the fluid dynamic pressure is obtained by a piezoelectric sensor installed on the tank wall; The static fluid pressure reference value is used. Through this quantification model, the system transforms complex microscopic parameters of wet fluids into directly controllable circulating pump flow parameters, solving the technical challenge of limited mass transfer within microchannels. Long-chain flexible molecules provide nanoscale displacement compensation through conformational inversion when heated, dissipating residual stress by utilizing molecular entropy changes and preventing edge peeling of circuit patterns. The charge inversion threshold of the hydrogen ion-sensitive functional group is... Potential dynamics of grafted organosilane bridging molecules on substrate surface under gradient conditions from 2.0 to 10.0 Measurement confirmed, The value corresponding to zero is taken as the isoelectric point of the charge. And as a triggering criterion for lateral growth suppression, during chemical deposition, the microfluidic unit delivers to the edge of the circuit pattern. conditioning solution, local Value deviation At least 1.5 units generate charge flips, and the local electrostatic field repels catalytic metal ions from entering the lateral growth site. The reduction of conductive metal atoms is confined to the normal direction of the self-assembled chemical anchoring layer, maintaining the wiring width and solving the problem of line edge blurring. The closed-loop control procedure for lateral growth suppression is as follows: micro-potential sensing electrodes are deployed every 50 micrometers at the edge of the microchannel, and the surface double layer potential millivolt value is collected at a sampling frequency of 100 Hz; the control unit compares the collected potential value with a zero potential reference preset based on the charge isoelectric point parameter to obtain the potential deviation vector; if the potential deviation approaches zero, it indicates that the growth boundary is about to break through the limit. At this time, the microfluidic pump injects acidic conditioning fluid into the edge region in increments of 0.1 μL per second, driving the interface potential to deviate from the isoelectric point until the millivolt value output by the sensing electrode returns to the safe threshold range. At the same time, the hydrogen ion sensitive functional group of the organosilicon bridging molecule is used to perform wiring width control; in the lateral growth direction of the circuit pattern, by changing the local area Value-driven functional groups generate charge flipping, thereby physically shielding catalytic sites in the lateral growth direction and achieving self-confined control of the growth boundary; after chemical deposition, plasma bombardment process is used to remove the self-assembled chemical anchoring layer exposed outside the circuit pattern, completing the manufacturing of high-density circuit boards.

[0031] Example 1: In production wiring spacing of In high-density flexible circuit board applications, polyimide is selected as the insulating substrate. After a self-assembled chemical anchoring layer is constructed on its surface, physically adsorbed organosilane bridging molecules remain in the non-scanning areas. Due to the micrometer-level spacing between the lines, the random metal nodules generated by the residual molecules can induce electromigration failure between adjacent conductors. Addressing the energy level difference in bonding strength between the aforementioned residues and the self-assembled chemical anchoring layer, the output power of the pulsed laser thermal field is adjusted to increase the cleaning energy level acting on the surface of the insulating substrate. At physical adsorption energy With chemical bond energy Within the band gap between them, the energy constraint rules are specifically satisfied. ,in, The physical adsorption energy of the physically adsorbed residue on the surface of the insulating substrate is given by the value of . , The chemical bond energy of the covalent bonds within the activated region of the pattern is given by the following value: , The cleaning energy level is defined in this embodiment as the cleaning energy level applied to the surface of the insulating substrate by an external cleaning energy field. .

[0032] In the cleaning energy level Under the influence of the kinetic energy of organosilanes bridging molecules in the non-scanning region, the kinetic energy exceeds the physical adsorption energy. Desorption occurs, and the molecules are removed by fluid slurry; simultaneously, the organosilane bridging molecules within the patterned activation region desorb due to… bond energy of covalent bond Greater than the cleaning energy level While maintaining anchorage on the substrate surface, this selective stripping method based on energy level differences restores the non-working areas on the insulating substrate surface to a bulk chemically inert state, providing a pure interface prerequisite for the subsequent directional nucleation of metal atoms. During the chemical deposition stage, the multidentate coordination functional groups in the organosilane bridging molecules are used to lock palladium ions, establishing a synergistic chelation potential well. When copper atoms are reduced in the patterned activation region, the initial displacement of the nucleus is restricted by the confinement effect of the synergistic chelation potential well. Within; by monitoring the fluid dynamic pressure parameters at the interface and adjusting the copper plating solution circulation flow rate, the conductor structure grows along the normal direction of the pattern activation region, eliminating the blurring phenomenon at the circuit edges; the finished circuit board produced by the above process is in to In the thermal cycling test, it experienced After one cycle, no microcracks were found at the bottom of the conductor, and the inter-line insulation resistance remained stable at [value missing]. The above describes how a molecular interface with potential energy gradients is constructed to transform a traditional physical resist mask into a logical mask based on chemical bond energy distribution, enabling simultaneous control of pattern accuracy and insulation reliability under a single interface architecture.

[0033] Example 2: When the wiring spacing is set to... In the high-density printed circuit verification test, to verify the impact of the energy level difference cleaning procedure on the interface insulation stability, a mass fraction of 100% was used. A self-assembled chemical anchoring layer was constructed using an aminopropyltriethoxysilane graft solution. Data was acquired using a physical experimental platform integrating a contact angle measurement unit and a pulse energy control unit, where the measurement resolution of the contact angle measurement unit was [missing information]. The power regulation accuracy of the pulse energy control unit is ; in setting the cleaning energy level At the same time, by balancing the efficiency of residue removal with the integrity of the chemical structure of the anchoring layer, the cleaning energy level is adjusted. Anchored to physical adsorption energy With chemical bond energy Within the energy level window formed; to simulate the mechanical disturbances in the actual production flow field, frequencies are superimposed within the cleaning tank at a frequency of and amplitude The vibration interference source is addressed by adjusting the duty cycle of the pulsed laser thermal field to control the cleaning energy level. The distribution is stepped, and the surface contact angle measurement value of the non-scanning area and the insulation resistance value between the lines are collected; Table 1 is a comparison table of interface performance parameters under different cleaning energy levels. According to the experimental phenomena recorded in Table 1, when the cleaning energy level In to When the interval is reached, the surface contact angle measurement value is... to At this time, physically adsorbed residues exist in the non-scanning area, inducing the insulation resistance between lines to be at a certain level. The magnitude; while when the cleaning energy level Upgraded to to At that time, the surface contact angle stabilizes at Nearby, the insulation resistance increased to The above indicates that the physically adsorbed residue desorbs under energy shock, and the covalent bonds within the patterned active region do not suffer thermal damage. Specific experimental data are as follows:

[0034] Comparison table of interface performance parameters under different cleaning energy levels (Table #1)

[0035]

[0036] Based on the gradient evolution data in Table 1, when the cleaning energy level Continue to increase to And exceeding the chemical bond energy Afterwards, the surface contact angle is maintained at However, the breakage of silicon-oxygen covalent bonds in the active region of the pattern leads to the stripping of the conductor structure, causing the insulation resistance to lose its measurement reference; this confirms the energy confinement rule. It is a necessary condition for achieving selective surface cleaning. By establishing a chemical mask method based on bond energy distribution on the surface of the insulating substrate, the conductive noise caused by metastable adsorption in the non-operating area is eliminated, providing quantitative support for the electrical isolation performance of ultra-fine lines.

[0037] Example 3: This example combines Figures 1 to 2 The manufacturing process of a high-density printed circuit board is described, such as... Figure 1 As shown, the manufacturing process involves step S101, where a self-assembled chemical anchoring layer is formed on the surface of an insulating substrate. This layer is composed of organosilane bridging molecules with multidentate coordination functional groups. Next, step S102 involves patterning the self-assembled chemical anchoring layer using a laser energy field. This establishes covalent bonds in the scanned area, forming a patterned activation region, while maintaining physically adsorbed residues in the non-scanned area. In step S103, energy level difference cleaning is performed, adjusting the external cleaning energy field density to be higher than the physical adsorption energy and lower than the chemical bond energy threshold to remove residues. The power output is adjusted in real-time based on monitored surface contact angle parameters. Then, step S104 introduces catalytic metal ions into the cleaned patterned activation region. The multidentate coordination functional groups establish chelation centers to fix the catalytic metal ions, limiting their initial nucleation displacement. Finally, in step S105, chemical deposition is performed in the patterned activation region, causing conductive metal atoms to nucleate in a directional manner and grow along the self-assembled chemical anchoring layer to restore the circuit pattern.

[0038] like Figure 2 As shown, the catalytic ion solution introduces catalytic metal ions into the pattern activation region, allowing the ions to enter the coordination region and thus enabling the multidentate coordination functional groups to establish chelation centers. The synergistic effect of the multi-coordination atoms restricts the nucleation displacement. On this basis, the chemical copper plating solution supplies conductive metal atoms to the pattern activation region to drive directional nucleation growth. At the same time, the concentration monitoring system monitors the ion concentration of the microchannel in real time. If the monitoring result shows that the concentration is lower than the threshold, the regulation mechanism is triggered to reduce the reaction temperature to slow down the nucleation rate. If the monitoring result shows that the concentration is normal, normal deposition continues. The above process is repeated until the circuit pattern is restored.

[0039] Example 4: In production with a depth-to-width ratio of When printing high aspect ratio printed circuit boards, the bottom of the micro-channels on the surface of the insulating substrate forms a thickness of [missing information]. The fluid retention layer causes the metal ion diffusion rate to be lower than the surface reduction rate; the control unit acquires the fluid dynamic pressure parameters of the interface of the patterned activation zone. According to the formula Calculate the thickness of the diffusion boundary layer ,in, The thickness of the diffusion boundary layer is given in units of 1000 ppm. , This is the measured value of fluid dynamic pressure, in units of... , The static fluid pressure reference value is [value]. , The proportionality constant is determined by the fluid viscosity, and its value is... The proportionality coefficient k was obtained by measuring the kinematic viscosity of the chemical copper plating solution using a rotational viscometer at a constant temperature of 25℃ and fitting it with the flow channel characteristic equation; when the calculated... Greater than And the duration reached At this time, the system increases the output frequency of the variable frequency pump to increase the circulation flow rate until the fluid dynamic pressure parameters are met. Increase Return to The following measures are taken to maintain the stability of the interfacial metal ion supply; to determine the molecular grafting topology parameters, a mixing molar ratio of short-chain bridging molecules to long-chain flexible molecules is used. The grafting solution was used to measure the polyimide substrate using atomic force microscopy. The interface displacement compensation amount under the environment is recorded. Peel strength after secondary thermal cycling; when the mixed molar ratio of short-chain molecules to long-chain molecules is at... to When the range is within, the interface displacement compensation is in to The peel strength did not decrease within the specified range.

[0040] When the mixed molar percentage of long-chain molecules is less than At this time, the displacement compensation caused by the flipping entropy of the flexible chain segment is insufficient to offset the thermal expansion displacement, resulting in shear cracks at the edge of the circuit; when the mixed molar ratio of long chain molecules is higher than At that time, the spatial steric hindrance effect caused the bonding density of the anchoring point to decrease to Therefore, the mixing molar ratio is set as follows: When determining the ion depletion state at the interface, the system collects the channel depth. With width Measure the values ​​and calculate the aspect ratio parameter According to the formula Calculate the ion concentration alarm threshold ,in, This is the ion concentration alarm threshold, in units of... , The bulk concentration of the chemical copper plating solution, in units of , This is the measured aspect ratio of the channel. The diffusion attenuation factor has a value of During chemical deposition, when the local metal ion concentration in the patterned active area is detected to be below the ion concentration alarm threshold... At that time, the system will reduce the reaction temperature from Lower to The reduction rate of conductive metal atoms is reduced by utilizing the temperature sensitivity of the reaction rate constant until the local ion concentration rises back to the ion concentration alarm threshold. above.

[0041] Example 5: In a mass production scenario using ceramic filler hydrocarbon resin substrates, a microfluidic pump is used to deliver the substrate surface loaded with a self-assembled chemical anchoring layer. Value to And adjust the step size to The test droplets were used to record the interfacial potential parameters in real time using an electrochemical workstation. ,in Interfacial dynamic potential, unit: ;when The test droplet whose value crosses from positive to negative and passes zero. Value At that time, the system records this value as the charge isoelectric point parameter of the organosilane bridging molecule, which serves as the logic triggering reference for driving the charge reversal of the hydrogen ion sensitive functional group in the subsequent wiring width control stage.

[0042] To address the surface energy fluctuations of insulating substrates from different production batches, a contact angle measurement unit was used to select areas in the non-scanning region of the insulating substrate. Sampling points were selected, and a volume of [volume value] was added. The deionized water was used to obtain the average value of the interfacial contact angle, which was then used as the contact angle reference value for this production task. In this embodiment, the measured for During the energy level difference cleaning stage, the system uses the formula... Calculate the surface cleaning deviation. ,in This refers to the surface cleanliness deviation, in units of... , This is the contact angle reference value, in units of , The measured surface contact angle of the non-scanned area is given in units of 1. ;when The absolute value is greater than At that time, the control unit The incremental increase in the output power of the pulsed laser thermal field until Return to Within.

[0043] Example 6: In the pre-deployment calibration process for production of carbon fiber reinforced composite substrates, a quartz crystal microbalance was used to collect the mass change parameters of the substrate loaded with a self-assembled chemical anchoring layer. ,in This represents the increase in mass per unit area, in units of... When detected The rate of change over time is continuous The number of sampling points is less than At that time, it was determined that the organosilane bridging molecule formed a monolayer at the interface, and the current cumulative time was locked as the standard grafting time. The values ​​in this embodiment are During the laser patterning scanning stage, the control unit follows the formula. Calculate laser scanning speed ,in Laser scanning speed, unit: , Laser output power, unit: , Preset line width, unit: , The energy conversion coefficient has a value of . .

[0044] In the on-site pre-inspection procedure following energy level difference cleaning, a volume of [unspecified quantity] is added to the non-scanning area of ​​the insulating substrate via a micro-volume nozzle. The grayscale mean parameters of the colorimetric reagent solution in the dropping area were obtained using an industrial camera. ,in This is a dimensionless grayscale parameter, and its value range is... to When detected The value is lower than At that time, the acoustic intensity adjustment procedure for physically adsorbed residues in non-scanning areas is executed, and the control unit follows the formula. Adjusting the output sound intensity of the ultrasonic cavitation field, among which The adjusted sound intensity is expressed in units of 1. , Original sound intensity, unit: With feedback adjustment of cleaning intensity, the non-scanning area Eventually stabilized above.

[0045] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A manufacturing process for high-density printed circuit boards, characterized in that, Includes the following steps: Step S101: A self-assembled chemical anchoring layer is formed on the surface of the insulating substrate. The self-assembled chemical anchoring layer is composed of organosilane bridging molecules with multidentate coordination functional groups. Step S102: The self-assembled chemical anchoring layer is patterned by using a laser energy field to establish covalent bonds between the organosilane bridging molecules in the scanned area and the surface of the insulating substrate to form a patterned activation region, while maintaining the physical adsorption state residue of the organosilane bridging molecules in the non-scanned area. Step S103: Perform energy level difference cleaning, apply an external cleaning energy field, and adjust the output power of the external cleaning energy field so that the energy density of the external cleaning energy field acting on the surface of the insulating substrate is higher than the physical adsorption energy threshold of the physically adsorbed residue and lower than the chemical bond energy threshold of the covalent bond, so as to remove the physically adsorbed residue in the non-scanning area. Step S104: Introduce catalytic metal ions into the pattern activation region after energy level difference cleaning, and use multidentate coordination functional groups to establish chelation centers to fix the catalytic metal ions and limit the initial nucleation displacement of the catalytic metal ions. In step S105, chemical deposition is performed in the pattern activation area to orient conductive metal atoms for nucleation and growth along the self-assembled chemical anchoring layer to restore the circuit pattern. In step S103, the surface contact angle parameters of the non-scanning area are monitored in real time using an online optical monitoring unit. The online optical monitoring unit includes a micro-spraying module and a high-speed imaging sampling module. The high-speed imaging sampling module captures the profile of the probe droplet under stroboscopic illumination and analyzes the surface contact angle parameters in real time. Based on the deviation between the surface contact angle parameters and the contact angle reference value preset based on the properties of the insulating substrate, the power output parameters of the external cleaning energy field are dynamically adjusted through closed-loop feedback control logic until the surface contact angle parameters reach the contact angle reference value.

2. The manufacturing process of a high-density printed circuit board according to claim 1, characterized in that, After performing energy level difference cleaning, the process also includes interfacial stress adjustment of the pattern activation region: an array of flexible pressure sensors integrated on the back of the insulating substrate is used to collect electrical signals to monitor the interfacial shear stress between the conductive metal atoms and the insulating substrate in real time. The flexible segments of organosilane bridging molecules are used to generate displacement deformation in response to the interfacial shear stress, so as to dissipate the residual stress caused by the mismatch of thermal expansion coefficients and avoid the edge peeling of the circuit pattern.

3. The manufacturing process of a high-density printed circuit board according to claim 1, characterized in that, In step S105, closed-loop control of liquid film thickness is performed: the piezoelectric pressure sensor installed on the wall of the chemical deposition tank is used to monitor the hydrodynamic pressure parameters at the interface between the pattern activation area and the chemical copper plating solution. The diffusion boundary layer thickness is calculated based on the hydrodynamic pressure parameters, and the circulation flow rate of the chemical copper plating solution is adjusted according to the offset of the diffusion boundary layer thickness relative to the target thickness to compensate for the diffusion flux of organosilane bridging molecules.

4. The manufacturing process of a high-density printed circuit board according to claim 1, characterized in that, Organosilane bridging molecules include silane coupling agents containing at least one polydentate coordination functional group selected from sulfur, amino, and carboxyl groups; the organosilane bridging molecules in the patterned activation region are connected to the surface of the insulating substrate through... Covalent bonds.

5. The manufacturing process of a high-density printed circuit board according to claim 1, characterized in that, Step S103 specifically includes: adjusting the cleaning medium. The charge is equal to the isoelectric point of the organosilane bridging molecules. The electrostatic repulsion after charge neutralization, combined with the mechanical scouring kinetic energy, destroys the physically adsorbed residues in the non-scanning region.

6. The manufacturing process of a high-density printed circuit board according to claim 1, characterized in that, The organosilane bridging molecule also has hydrogen ion-sensitive functional groups; the growth in step S105 includes wiring width control: in the lateral growth direction of the circuit pattern, by changing the local area The value drives the hydrogen ion-sensitive functional groups to generate charge flipping, thereby physically shielding the catalytic sites in the lateral growth direction.

7. The manufacturing process of a high-density printed circuit board according to claim 1, characterized in that, During chemical deposition, the metal ion concentration in the microchannels within the patterned activation region is monitored; when the metal ion concentration falls below a preset concentration threshold, the chemical deposition reaction temperature is reduced to [value missing]. to Between these, the nucleation rate is slowed down and the interfacial ion depletion phenomenon is eliminated.

8. The manufacturing process of a high-density printed circuit board according to claim 1, characterized in that, The external cleaning energy field is composed of an ultrasonic cavitation field and a pulsed laser thermal field. By adjusting the pulse width of the pulsed laser thermal field, the instantaneous temperature gradient on the surface of the non-scanning area is controlled, so that the molecular kinetic energy of the physically adsorbed residue exceeds the physical adsorption energy threshold.

9. The manufacturing process of a high-density printed circuit board according to claim 1, characterized in that, Energy level difference cleaning satisfies the following energy constraint rules: ,in, The physical adsorption energy is the adsorption energy of physically adsorbed residues on the surface of the insulating substrate. The chemical bond energy of the covalent bonds within the activated region of the pattern. The cleaning energy level is the cleaning energy level applied to the surface of the insulating substrate by an external cleaning energy field; and All parameters are fixed parameters that were pre-determined based on the material properties of the organosilane bridging molecules and the insulating substrate.

10. The manufacturing process of a high-density printed circuit board according to claim 1, characterized in that, The manufacturing process is used to produce wiring with a spacing of less than [specified value]. The printed circuit board; conductive metal atoms including copper, nickel or gold atoms; after chemical deposition, the process also includes removing the self-assembled chemical anchoring layer exposed outside the circuit pattern using a plasma bombardment process.

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