CN113573488A

CN113573488A - System for producing conductive patterns by selectively activating insulating materials by combination of laser and chemical

Info

Publication number: CN113573488A
Application number: CN202110746729.3A
Authority: CN
Inventors: 胡宏宇; 王恒亮
Original assignee: Dct Tianjin Technology Development Co ltd
Current assignee: Dct Tianjin Technology Development Co ltd
Priority date: 2021-07-01
Filing date: 2021-07-01
Publication date: 2021-10-29

Abstract

The invention relates to a system for selectively activating an insulating material to manufacture a conductive pattern by combining laser and chemistry, which comprises one or more sets of data acquisition and processing systems, an equipment operating system, a laser light source, a light beam shaping and transmission system, a laser focusing system, a workpiece clamping and workpiece rotating and overturning system, a movement and control system between a workpiece and a light beam, an automatic and manual workpiece feeding and blanking system, a positioning and detection visual system, a laser power monitoring and compensating system, a cleaning and constant temperature system, a laser and equipment safe use system and the like, can match different beam waist diameters by taking energy and power on a unit area as constant quantities according to a circuit pattern structure to generate optimized processing parameters and processing data, and can change the beam waist diameter of the interaction of the laser and the material on line under the condition that the energy and the power on the unit area are constant at set values, and (5) processing.

Description

System for producing conductive patterns by selectively activating insulating materials by combination of laser and chemical

Technical Field

The invention belongs to the technical field of circuit manufacturing, relates to the manufacturing technology of a 3D-MID device, and particularly relates to a system for manufacturing a conductive pattern by selectively activating an insulating material through combination of laser and chemistry.

Background

A 3D-MID, Three Dimensional Molded Interconnect Device (Three Dimensional Molded Interconnect Device), is an electronic Device that integrates the functions of supporting and shielding of a plastic housing, as well as the functions of shielding and antenna, etc. that are created by the combination of a mechanical entity and a conductive pattern, by fabricating a conductive pattern on the insulating surface of an injection Molded workpiece. Since the 3D-MID has both mechanical and electrical functions, it is also called a Three Dimensional electromechanical Integrated Device (Three Dimensional electromechanical Integrated Device).

In recent years, the wide application of Additive Manufacturing technology opens up a new application opportunity for the existing 3D-MID technology, various three-dimensional electromechanical integrated devices with mechanical functions can be obtained by performing 3D-MID processing on the insulating surface of a mechanical structural part obtained by Additive Manufacturing (Additive Manufacturing), intelligent, communication, sensing and control functions can be integrated in a mechanical system, and the functions of increasing performance, improving assembly space and reducing cost are achieved.

There are various techniques for manufacturing 3D-MIDs, such as subtractive, additive and semi-additive techniques. The essence of the technology is that a conductive material layer is selectively manufactured on an insulating material according to the layout and the wiring pattern, and insulating base materials with different shapes and performances are matched with conductive layers with different pattern structures to realize the electrical and mechanical functions required by the design. In either method, the basic requirements for the product include: the conducting layer has good electrical performance and has enough adhesive force with the insulating base material; the geometry of the conductive pattern is accurate, and the relative position of the conductive pattern and the insulating substrate is accurate.

The plastic chemical plating technology, together with the upstream plastic materials, liquid medicine, equipment and branches of the plastic chemical plating technology in different fields, including the application in the electronic industry, has formed a manufacturing industry chain and is an indispensable basic technology in modern industry. The combination of the plastic chemical plating technology and the electroplating technology can meet the requirements of the 3D-MID on the adhesive force and the electrical performance of the conductive layer. The laser, a high-energy photon flow, is positioned accurately, has fine size, good consistency and good selectivity under the control of a digital system, and can meet the requirements of 3D-MID on the size and position precision of a conductive pattern. At present, the "plastic chemical plating + laser method" of selecting a region to which a conductive pattern is added on an insulating substrate by laser processing, and depositing a conductive metal on the selected region by plastic chemical plating or electroplating after plastic chemical plating is widely used.

German inventors gerhar naundorf and Horst Wissbrock, in patents DE 19723734 and DE 19731346 and their respective corresponding patents US6,319,564 and US6,696,173, describe methods for producing seeds required for electroless plating by laser at the time, and disclose a technical scheme for selectively producing a conductive pattern on an insulating material by coating a non-conductive organic metal chelate containing heavy metal palladium/Pd/palladium on the surface of a porous insulating material, destroying the coordination between the organic substance and the metal substance by excimer laser with a wavelength of 248nm to expose the metal palladium, and using the metal chelate as a seed for depositing the metal substance in the subsequent electroless plating. The two inventors, DE 10132092 and US7,060,421B2, also disclose a circuit-making structure scheme in which a non-conductive spinel metal oxide containing copper and another cation is doped into a thermosetting plastic, and then the laser-etched plastic releases a metal core and forms a rough surface as a starting region for the adhesion of nucleation seeds and metal substances during the subsequent electroless plating, so as to solve the problems of the prior art, such as large proportion of nucleation substances, poor lead-free welding high temperature resistance, difficulty in injection molding, and the like. Aiming at the limitation of the two German inventor patents, the Chinese inventor Linyun and the like propose new schemes in the patent of composite material containing metallocene acylhydrazone type complex and preparation method with the application publication number CN103589065A, and the patent of micro-aeromagnetic and electro-technology Limited in Shenzhen of Chinese patent owner, and the patent of composite component and preparation method of three-dimensional circuit manufacturing process and laser plastic raw material with the application publication number CN 101859613A, and substitute substances or improved substances are adopted as additives and are doped into plastics so as to release seeds for the subsequent chemical plating deposition of metal after laser processing. Unlike the uniform doping of active materials into an insulating plastic body, the Gentianyou science and technology Limited, Shenzhen, patent applicant, in the patent of application publication No. CN102242354A, selective chemical plating Process and corresponding laser coating and preparation method thereof, discloses a method for manufacturing 3D-MID. In the method, a coating containing an active metal oxide additive is applied to the surface of a plastic object to release a substance that can act as a seed in the electroless deposition of metal after laser machining.

Based on the idea that metal oxides can release metals, in DE102006017630.8, the inventor Gerhard Naundorf also disclosed a technical solution for using laser to process aluminum nitride-containing materials to release aluminum species as starting active materials in the subsequent electroless plating. To solve the problem of thermal degradation of plastics caused by the incorporation of copper and chromium containing metal oxides, patent US9,676,927B2 discloses the use of inorganic silicates as the cladding shell for the metal oxides to form a core-shell structure, which is incorporated into the plastic and then processed by laser. In the application of patent publication No. CN 103088321A, Structure and manufacturing method for selectively forming metal on plastic substrate, Shenzhen micro-aeromagnetic technology Limited, a core-shell additive scheme is proposed. In the scheme, inorganic salt containing nickel and zinc and an indium tin oxide material are coated by a coupling agent to form an additive with a core-shell structure, and the additive is doped into plastic, so that active groups can be released after laser processing and can be used as seeds for depositing metal by chemical plating.

While the technology of pre-doping a certain active material into plastic is continuously developed, a technology of manufacturing a circuit structure without doping an active material into plastic is also appeared. Patents CN106211611A "method and conductive circuit for establishing continuous conductive circuit on surface of non-conductive substrate", CN105744749A "method for forming conductive circuit on insulating surface of base material", and CN103477725A "harmless technology for establishing continuous conductive circuit on surface of non-conductive substrate" disclose technical schemes for making conductive structure by addition method on insulating material, these methods are based on general plastic chemical plating and electroplating technology, after the workpiece is globally activated and is processed by chemical plating, active metal groups added on the surface of the insulating material are removed by laser along the outer envelope line of the required conductive pattern, or removing the chemical plating deposition metal layer on the surface of the insulating material and the active metal group below the chemical plating deposition metal layer along the outer envelope line of the required conductive pattern by using laser, so that the required conductive pattern is electrically insulated from the non-pattern area to form two electrically separated areas; then, carrying out area selective electroplating, and electroplating conductive metal only on the required circuit pattern area to ensure that the thickness of the conductive layer in the conductive pattern area is larger than that in the non-conductive pattern area; and finally, removing the non-electroplated thickened thin conductive layer which is originally activated and deposited on the non-conductive pattern area by chemical plating by using a differential etching method and the like to prepare the product. The patent CN1039995559A "preparation method of conductive trace structure and base material with conductive trace structure", CN104221135A "double-sided circuit board and preparation method thereof", CN103547055A "circuit substrate with circuit pattern and manufacturing method thereof", CN104451794A "electroplating method with uniform plating thickness and product thereof", and CN104902710A "housing with two-dimensional circuit structure and manufacturing method thereof" are improved, the steps of prefabricating conductive pattern on the surface of insulating material by laser, i.e. performing area selective processing by laser, only roughening the surface of the required conductive pattern area to increase the adhesive force of conductive layer and insulating material are added before activation and chemical plating; then, global activation and chemical plating are carried out, namely active metal groups are added to all the areas of the workpiece, and a first metal layer is added to the material on all the areas of the workpiece by a chemical plating method; then, removing the chemical plating deposition metal layer on the surface of the insulating material and the active metal group below the chemical plating deposition metal layer along a selected path by using laser to form an insulating channel, and separating the active metal group layer and the first metal layer on the active metal group layer into two regions which are mutually electrically insulated; then, carrying out area selective electroplating, and electroplating and depositing a second metal layer only on the area containing the conductive pattern; finally, the conductive material of the non-conductive pattern area is removed by differential etching or by the difference of surface adhesion, and the product is obtained. In patent application publication No. CN102612271A "three-dimensional circuit on structural member and method for making the same", inventor chong et al, published a technical solution without plastic chemical plating by first coating conductive paint and then removing excess conductive material except conductive pattern by laser.

The applicant Shenzhen Shiyomo science and technology Limited, in the patent of application publication No. CN104975276A patent of method for forming selective metal circuit on plastic surface and plastic component, proposes a double-roughening technical scheme, i.e. first performing laser roughening on the pattern region of a plastic workpiece, then performing chemical roughening to form stronger adhesive force to active groups, and then performing chemical plating on a conductive layer to manufacture a conductive structure. In order to improve the surface properties of plastics, the applicant LPKF Laser & Electronics AG disclosed a method of increasing the surface roughness of plastic parts in US9,924,601B2. The method uses laser to manufacture the microstructures on the injection mold, when the workpiece is molded, the microstructures are embedded into the surface of the region of the plastic workpiece needing to manufacture the conductive pattern, so that the surface area of the conductive pattern region is increased, the bonding force between the region and the conductive layer added through electroless plating is increased, and the purpose of selectively manufacturing the conductive pattern on the plastic can be achieved. In patent application CN108476588A, the applicant Plasma Innovations ltd/Plasma Innovations and LPKF laser and electronics, discloses a method of manufacturing conductive structures according to the surface properties of insulating materials. The surface of the workpiece is divided into two types of areas with different surface properties by processing the surface of the insulating material, wherein the adhesive force between one area and the conductive material is obviously smaller than that between the other area, the conductive material is coated on the workpiece by using methods such as laser, plasma, chemistry and the like, then, the removal strength is controlled, and only the conductive material on the area with smaller adhesive force with the conductive material is removed by using a removal method such as dry ice cleaning and the like to form the conductive structure.

These patents relating to the manufacture of conductive structures on plastics can be grouped into three categories: doping active materials in the plastic, carrying out laser selective processing, only releasing active groups in the conductive pattern area, and then carrying out regional chemical plating; global activation and chemical plating, wherein conductive materials are removed by laser, and the surface of a workpiece is electrically partitioned, locally plated and the like; laser is directly or indirectly used for manufacturing a roughened surface in the conductive pattern area, and the conductive material is selectively coated by the laser.

The technical scheme of the first kind of patent is carried out by doping substances which can be activated by laser into plastic, and the added active substances play a role of seeds when exposed in a conductive pattern area after laser processing on one hand, so that more active groups and metal deposition are facilitated in the subsequent chemical plating process; on the other hand, the process of laser machining to expose these active substances also increases the roughness of the plastic surface of the conductive pattern area to some extent. These patents are characterized by the fact that, under the action of both active groups and increased surface roughness, a conductive structure is obtained on the plastic workpiece, after chemical plating. It has to be noted, however, that the incorporation of active substances may add to the cost of the plastic, increase the complexity of the processing and, moreover, these active substances may have a negative effect on the properties inherent to the plastic.

The second patent uses a technique of chemical plating activation, or chemical plating, and then removes the active groups by laser, or removes the chemical plating layer and the active groups thereunder, to make an insulation channel, so as to electrically isolate the required conductive pattern area from the non-conductive pattern area, thus, only the pattern area can be electroplated with conductive metal, and the conductive layer thickness of the pattern area is far larger than that of the non-pattern area, and then the conductive layer of the non-pattern area can be removed by differential etching, etc., so as to obtain the required conductive circuit on the insulation material. However, these patents do not solve the problem of the environmental burden of the roughening process before the conventional electroless plating, and the technical description of the laser processing parameters is too general, and it is not easy to refer to the implementation.

The third patent technical solution focuses on the roughening step before the plastic chemical plating, and after directly manufacturing the rough surface in the pattern area or indirectly manufacturing the rough surface in the pattern area, the plastic chemical plating and electroplating deposition of the conductive layer are performed, and finally, the removal strength is controlled, and only the redundant conductive material deposited outside the conductive pattern area is removed, so as to manufacture the product. Among them, in the US9,924,601B2 patent, a scale for judging roughness is given; in the CN108476588A patent, a judgment value is given for the magnitude of adhesion associated with roughness, and a method and apparatus for removing a conductive layer in a non-pattern area. Although this type of approach is aware of the effect of coarsening on adhesion, there are still detailed problems to be solved in the art, particularly with respect to the selection of laser parameters, and further more quantifiable, implementable information.

In recent years, the laser technology is greatly improved, the power is high, the pulse repetition rate is high, and the pulse duration is short, so that the cost performance of laser beam generation is greatly improved; on the other hand, the further refinement, the multiple functions and the wide application of the electronic products generate higher requirements on the quality and the cost of the 3D-MID. By combining the technical information and the patent scheme, the method combining laser processing and plastic chemical plating is the mainstream technology of the current 3D-MID manufacturing industry. However, compared with the progress made by laser technology, the laser processing has the defect that the laser processing does not play a role in greatly increasing the adhesive force while determining the selective action of the pattern area; in addition, various processing methods do not fully utilize the advances of high power, high pulse repetition rate and short pulse duration of the current lasers, and cannot make the best use of the current lasers. Aiming at the space which can be improved, the invention improves the quality, efficiency and practicability, and more economical and environment-friendly aspects of the existing 3D-MID technology manufactured by the method combining laser processing and plastic chemical plating.

The product quality is the primary goal of all manufacturing processes, the most important factor for determining the quality of the 3D-MID is the adhesion between the conductive layer and the insulating layer, and the excellent adhesion comes from the surface performance of a proper base material. It is therefore a primary objective of the present invention to optimize the laser processing parameters and chemical treatment process to provide sufficient adhesion of the conductive material to the base insulating material.

The above-disclosed technical information and patents show that after proper roughening treatment, the chemical plating layer and the substrate can obtain good adhesion for most plastics even if special active materials are not added. It is clear that the goal of laser machining is to create a micro-rough surface, creating a larger specific surface area, after being projected onto a selected area of a plastic workpiece. However, the laser light projected to the workpiece does not always act on the material, and even if it does, it is not necessarily effective. This is because the laser beam contacts the material and three phenomena occur, namely reflection, transmission and absorption:

r+a+t＝100％

r is reflectance, a is absorptance, and t is transmittance. The higher the absorptivity is, the smaller the depth of the laser energy incident on the material is, the action of the laser and the material is generated in the surface area irradiated by the light beam, the action range is limited to a thin layer, the energy obtained on the unit material is large, and the processing effect is good; conversely, if the absorption rate is low and the transmittance is high, the depth of the laser incident material is greater, most of the light energy will not be released on the surface of the material but will pass through the material until the light is transmitted out of the material, the action of the laser and the material will occur on the light column formed by the light inside the material, the action range is a solid with the same height as the incident depth, the concentration of the energy on the unit material during the passing process is low, and the processing effect is poor.

The magnitude of the absorption is related to a number of factors but depends primarily on the wavelength of the laser and the material itself. Compared with the common industrial laser equipment, the wavelengths of the laser equipment are approximately 10.6 microns, 1064nm in an infrared band, 532nm in a visible band and 355nm in an ultraviolet band, the photon energy of the laser with different wavelengths is different, the shorter the wavelength is, the higher the energy is, the photon energy of infrared light is small, the effect with materials is mainly thermal effect, the photon energy of ultraviolet light is large, and the effect with materials is mainly chemical effect. The carbon dioxide laser wavelength is about 10.6 mu m, is in the middle infrared band of the infrared band, is just equivalent to the stretching and rotating vibration frequency of plastic macromolecules, is easily absorbed by plastic, but has the incident depth of hundreds of microns, low photon energy of about 0.12 electron volt, large thermal action and low cost performance of the laser. The laser in the UV wave band is easy to be absorbed by the plastic, even the laser with the wavelength of 355nm has enough absorption rate, the incident depth is only several microns, the photon energy is as high as about 3.5 electron volts, the damage to the molecule is enough generated, the chemical action is obvious, the heat effect is small, and the processing process is closer to cold processing. Most plastics are transparent or translucent in nature for visible and near infrared light, meaning that most of the energy is not absorbed after the light is projected onto the surface of the plastic material, but rather is gradually dissipated or displaced as it travels through the material as it is transmitted, without being focused at a point. The fiber laser is the mainstream in the current market, the wavelength is about 1 μm, the photon energy is about 1.16eV, the absorption rate is low, the energy is dispersed, the macromolecule cannot be directly destroyed, the movement of the molecule can only be increased on the whole, the thermal action is large, and the processing effect is not ideal. For this reason, the first type of patent mentioned above greatly improves the processing effect after the additives are incorporated, because the additives not only provide active groups, but also increase the absorption rate of the material, so that the laser with a wavelength of about 1 μm can be absorbed in a larger proportion, the energy concentrated on the unit material is larger, thereby the function of destroying the material structure can be achieved, and a certain coarsening effect can be generated. However, it must be seen that if a plastic without additives of a specific kind is processed by using ordinary infrared light of about 1 μm, the thermoplastic will be remelted and fluidized due to the thermal action of the infrared light, which not only does not achieve the roughening effect required for chemical plating of the plastic, but also makes the surface smoother. Based on the above mechanism of interaction between laser and plastic, one of the specific objects of the present invention is to take coarsening of plastic without active material as an object, and based on the mainstream laser in the market, to solve the problems of small photon energy, large thermal effect, high light transmittance and low absorption rate of material during laser coarsening in the prior art, and to provide a definite laser processing parameter and provide a solution capable of ensuring product quality.

The 3D-MID has both electrical and mechanical functions and is used in electronic products. Like other electronic and mechanical parts, the level of machining efficiency is an important criterion for determining whether the manufacturing technology is advanced or not.

As mentioned above, 3D-MID laser processing is a pattern processing, and normally, different product patterns are different in shape and different in width of geometric pixels constituting the pattern. However, the current laser material processing equipment only has one focused laser beam, the beam waist diameter is fixed, and the beam waist diameter of the common material processing equipment is between 5 and 100 μm, especially between 15 and 30 μm; the data processing software and operating software provided with the device also provides a machining solution only at this fixed diameter. For 3D-MID processing, when the width of a geometric pixel is different from the beam waist diameter, a plurality of times of processing are needed for the edge lapping edges of a plurality of single laser beams until the scanned width of all the laser beams is exactly the same as the width of the pixel, when the width of the pixel is not integral multiple of the beam waist diameter, two adjacent laser beams are overlapped without fail, and the laser energy borne by the overlapping area is larger than that of the rest areas, so that the energy in the processing area is uneven; furthermore, with multiple passes of a spot, for example, 20 μm in diameter, the processing speed is slow and the economy is poor for products containing patterns of relatively large width. Based on the problems, a technical scheme which can ensure the processing quality and can ensure the processing speed to be higher is provided by applying a mainstream laser light source in the current market and aiming at most 3D-MID pattern conditions through optical design and software design, and the method has great economic significance for manufacturing the 3D-MID by using a plastic chemical plating and laser method and is also one of specific targets of the invention.

The 3D-MID device integrates electromechanical functions into a whole, has wide application possibility, and is manufactured by a process involving various materials, various devices and various operating conditions, and needs specific and specific process flows and parameters. Firstly, there are many varieties of plastics, and the parameters required to be selected for roughening and chemical plating treatment of plastics include options such as chemical liquid components, temperature, treatment time and the like. Meanwhile, the quality and speed of laser processing also depend on the software and hardware configuration of the equipment and the choice of technical parameters. It can be seen that the method of laser processing combined with plastic electroless plating to produce 3D-MID is affected by multiple factors, each of which has various inherent effects and limitations, increasing the engineering difficulty of implementing the technique. Another objective of the present invention is to seek out the influence relationship between various factors in the laser processing and chemical treatment processes, to provide a method for independently or comprehensively optimizing laser processing parameters and pre-treatment parameters for plastic chemical plating, to establish the boundary condition between laser roughening and chemical roughening, to determine the range of process parameters, and to develop the 3D-MID technology manufactured by the method combining laser processing and plastic chemical plating into a mature and stable production process, which is easier to implement.

Disclosure of Invention

The invention provides a system for manufacturing conductive patterns by selectively activating insulating materials through laser and chemistry aiming at the defects of the existing 3D-MID manufacturing technology, provides a technical scheme which can ensure the processing quality and can ensure the processing speed to be faster through optical design and software design aiming at most of 3D-MID pattern conditions by applying a mainstream laser light source on the current market, has great economic significance for manufacturing 3D-MID through a plastic chemical plating and laser method, and is also one of the specific targets of the invention.

The equipment for realizing the method of the invention consists of one or more sets of data acquisition and processing systems, an equipment operating system, a laser light source, a light beam shaping and transmission system, a laser focusing system, a workpiece clamping and workpiece rotating and turning system, a workpiece and light beam movement and control system, an automatic and manual workpiece feeding and blanking system, a positioning and detection visual system, a laser power monitoring and compensating system, a cleaning and constant temperature system, a laser and equipment safety use system and the like. The laser light source parameter range is as follows:

wavelength: 266nm-10700 nm;

pulse width: 10fs-1000 mus;

pulse repetition rate: 1KHz-100 MHz;

average power: 1W-10000W.

The laser power monitoring and online compensating system is an important means for ensuring the consistency of the processing quality of equipment, and the equipment is provided with the laser power monitoring and online compensating system which comprises a laser power meter arranged on a working table and a control system for adjusting the output power of a laser according to the laser power of the table. The beam shaping and transmission system of the apparatus comprises not only the expansion or reduction of the diameter of the laser beam by the optical devices, but also an optical treatment system for homogenizing the light energy in a section perpendicular to its direction of transmission, in order to ensure a uniform overall and local processing quality over the entire range to be processed.

In general, laser output by a laser is gaussian, energy/power of the laser is distributed in a bell shape in space, the middle of the laser is high, the periphery of the laser is low, the laser is not uniform in a circular area acted by a light beam and a material, the energy/power difference between the periphery of the circle center and the periphery of the circle center is large, when the beam waist diameter of the light beam is large, or a digital micromirror and a diffraction optical device are adopted as light beam transmission means, the phenomenon of nonuniform distribution of light energy/power is more obvious, and processing quality is affected. The equipment adopts the design of adding a device which can enable laser to be distributed more uniformly after expanding beam, for example, adding an optical homogenizer, for example, adding a diffraction optical shaping device Top-Hat/Flat-Top, and shaping Gaussian into Flat Top light, and then projecting the Flat Top light to the surface of a workpiece after light beam transmission and focusing. Therefore, the energy density and the power density between any laser pulse acted on the workpiece are enabled to be uniform and consistent on the whole after the beam waist diameter of the light beam is changed by keeping the energy density and the power density constant; after beam expansion, the light beam is shaped by the light homogenizing device, and then transmitted and projected on a workpiece, so that the energy density and the power density in each laser pulse action area are locally uniform and consistent.

After beam expansion and light homogenization, the device of the invention adopts a light beam transmission means more suitable for laser sources with high pulse repetition frequency, such as ultraviolet, picosecond and femtosecond pulse lasers, and comprises the following steps: diffractive optical element/DOE, electro-optic modulation device/EOD, acousto-optic modulation device/AOD, Polygon Scanner/Polygon Scanner, Resonant scanning device/resonance Scanner, galvanometer Scanner/Galvanic Scanner, Piezo-electric and micro-electromechanical Scanners/Piezo- & MEMS Scanners, micro-Scanner/Microscanner, digital micro-mirror device/DMD. These light beam transmission devices may be used alone or in combination.

For example, a polygon scanner is used to transmit the homogenized laser beam to an optical focusing system by means of a mirror group rotating at a high speed. Compared with a galvanometer scanner, the scanning device can position light pulses at a specified position in a vectorization mode, transmit light beams by using the polygon mirror, position the light pulses at the specified position in a point-by-point and line-by-line lattice scanning mode, but more light pulses can be distinguished and reflected in unit time, and the suitable pulse repetition rate is higher and can reach 10MHz or even 20 MHz.

For another example, the DMD, which is a digital micromirror device, is used alone to form a multi-spot structured light corresponding to the shape and size of one or more pixels or patterns or segments thereof, according to the shape of the pattern, and then the light beam set forming the multi-spot structured light is reflected to the subsequent optical focusing mirror. The digital micro-mirror device is used as a light beam transmission means, and hundreds of thousands of light beam elements are used for forming structured light matched with patterns to form a light beam set, and the structured light is reflected and transmitted in a projection mode. Compared with vectorization scanning processing of a galvanometer scanner or lattice scanning processing of a multi-prism scanner, the projection reflection of the digital micromirror device is large-range stamping processing and is faster.

For another example, after a pair of AODs or EODs are connected in series, the beams are transmitted to a pair of galvanometer scanners connected in series at a high speed within a small range/angle of the X axis and the Y axis, and the galvanometer scanners continue to transmit the beams along the X axis and the Y axis within a larger range/angle after continuing the beams transmitted by the AODs. AOD and EOD are scanning devices based on optical mechanisms, which implement distribution of laser beams at different positions by applying acoustic waves and electric waves to a crystal to change the refractive index of the crystal to light, thereby changing the transmission direction of laser light passing through the crystal. Different from scanning devices based on mechanical mechanisms, such as a galvanometer, a polygon mirror and the like, the AOD and the EOD have no moving mechanical parts, high reaction speed and high scanning resolution, and the problems of low reaction speed caused by mechanical motion inertia and low angle resolution caused by inertia do not exist. However, the optical scanning mechanism of AOD and EOD has limited change of refractive index, small scanning range and small optical numerical aperture ratio, and is not suitable for being applied alone in the field of micromachining of materials. The invention applies the AOD and the EOD in series with the galvanometer, combines the advantages of high AOD and EOD reaction speed and high resolution with the advantage of large scanning range of the galvanometer, and overcomes the defects of small numerical apertures and small scanning range of the AOD and the EOD. In addition, the scanning device of the optical scanning mechanism is connected with the mechanical scanner in series, and the defects of low response speed and low resolution of a galvanometer which is moved by the mechanical scanner can be overcome. Thus, two scanning mechanisms are applied in series, so that the performance of a light beam transmission system is optimized, and the laser light source is more suitable for the laser light sources with high pulse repetition rates of picoseconds, femtoseconds and the like at present and the micromachining carried out by the light sources.

For example, several diffractive optical elements/DOEs are mounted in parallel in the optical path to form an optional optical path, a certain optical path is selected by a reflector capable of electrically changing the reflection angle, each diffractive optical element in parallel corresponds to one beam size and is processed into multi-point light with different points, the multi-point light is projected to a subsequent galvanometer scanner or multi-prism scanner, and then the multi-point light is reflected again, enters an optical focusing mirror to be focused and then is projected to the surface of a workpiece.

Most 3D-MID devices require the processing of circuit patterns on curved surfaces. When the three-dimensional workpiece curved surface is processed, the Z-direction focusing system can be changed along with the Z-direction position, so that the light beam keeps a focusing state on the processed surface and is vertical to the processed surface. The system consists of optical and mechanical parts. Wherein, the optical part is a focusing lens with the focal length changing along with the height change of the surface of the workpiece. The focusing lens consists of a static lens group and a movable lens group, and the movable lens group is controlled by the control system to move correspondingly along with the height change of the surface of the workpiece, so that the focusing point of the laser beam is always positioned on the curved surface of the workpiece in the dynamic processing process. The mechanical part of the Z-direction focusing system consists of an axial rotating mechanism and a radial rotating mechanism of the workpiece. The axial rotating mechanism drives the workpiece to integrally rotate along the long shaft of the workpiece, so that all the surfaces of the three-dimensional workpiece can rotate and face the vertically downward laser beam to be in a state to be processed; the radial rotating mechanism drives the workpiece to rotate in the radial direction, so that the upward surface to be processed of the workpiece is kept in a vertical state with the vertical laser beam.

The invention is characterized in that the processing result is actually measured, the relation between the laser parameter and the processing result is obtained, and the relation is applied to the processing process through a data processing system and an equipment control system. The equipment actually measures a processing result through a positioning and detecting vision system, and the system comprises a photographic system for identifying, checking and measuring the workpiece and the pattern characteristic structure on the workpiece and an illuminating light source capable of dynamically matching the texture, the texture and the color of the material; the system comprises an optical and mechanical structure for positioning and projecting the light beam on the workpiece to determine the position; the system also comprises software for driving and controlling the photographing, lighting and positioning motions, and data acquisition, processing and output software for identification, inspection, measurement and positioning.

Processing a fine conductive structure, requiring a clean environment, at a constant temperature; maintaining equipment performance, extending equipment life also requires clean environments, constant temperatures. The equipment is provided with a cleaning system and a constant temperature system which are both controlled by an equipment operating system, wherein the constant temperature system is arranged in the equipment or at the top end of the equipment; the cleaning function is realized by a blowing and dust collecting system. The suction port of the dust collection system is closer to the workpiece and is positioned at the lower part of the processing head, and an air inlet with a cross section smaller than the sectional area of the suction port and provided with a filter screen is arranged at the lower part of the processing head and opposite to the suction port and at the same position with the suction port horizontally; the air blowing port of the air blowing system is closer to the optical protective mirror and the focusing mirror, is positioned at the middle upper part of the processing head, is higher than the air suction port in the horizontal position, is positioned in the middle of the processing head, is opposite to the air blowing port and is provided with an exhaust hole provided with a filter screen at the same horizontal position as the air blowing port; the air suction port and the air blowing port are arranged on the same side of the machining head or are arranged in opposite directions; the blowing and sucking modes can be started simultaneously or alternately and alternately according to the processing progress, the mode comprises a sucking mode when materials are removed, and the blowing mode is switched after the materials are cut completely or drilled completely to form a cutting or drilling starting point.

In the invention, a data acquisition and processing system, an equipment operation system, a laser light source, a light beam shaping and transmission system, a laser focusing system, a workpiece clamping and workpiece rotating and overturning system, a motion and control system between a workpiece and a light beam, an automatic and manual workpiece loading and unloading system, a positioning and detection visual system, a laser power monitoring and compensating system, a cleaning and constant temperature system, a computer and a communication system which are formed by the same circuit main board for operation, control and drive of a safe laser and equipment use system, or a computer and a communication system which are formed by a plurality of circuit boards. The data acquisition and processing system and the equipment operating system are respectively two independent software packages and use different user interfaces; or as a software package, using the same user interface.

The laser processing equipment in the existing 3D-MID technology generally only provides a beam with a beam waist diameter to act on materials. Such a technique requires a plurality of scanning shifts to cover all pixel regions when processing a wide pixel with a small beam waist diameter beam, and the processing speed is slow. In addition, only one beam waist diameter technology is adopted, when the width of a pixel is not integral multiple of the beam waist diameter, partial areas need to be overlapped to realize processing of all pattern areas, so that the overlapped area is processed for multiple times, the received light energy density is obviously higher than that of other areas, and the processing quality is inconsistent.

The invention adopts a processing scheme that the laser light energy density and the light power density can be fixed, but the beam diameter is variable. Firstly, the consistency of processing quality can be ensured by fixed light energy density and light power density; and secondly, the beam diameter is variable, and the corresponding beam expansion multiplying power can be matched according to the independent pixel width of each 3D-MID circuit in processing. Thus, when the pixel width is large, the beam processing with the beam waist diameter matched with the width is adopted, the speed is high, the power resource of the laser light source can be fully utilized, and when the pixel with the large width is processed, the whole area is covered at one time without multiple staggered scanning. In addition, when processing a pixel with a larger width, the beam waist diameters are added to two or more beams with the same beam waist diameter or different beam waist diameters which are exactly equal to the width of the pixel, the edges of the two or more beams are adjacent to the edges, overlapping is not needed, all areas in the pixel are scanned, the processing density of each position in the area is the same, and the processing quality is consistent.

In the production of the 3D-MID, the default beam waist diameter D is provided for the laser processing equipment with the determined laser light source and the beam transmission system, the determined liquid medicine system and the determined plastic variety_r0Intrinsic minimum beam waist diameter d_rminAnd maximum beam waist diameter d_rmaxRespectively corresponding to a pattern width of d₀，d_minAnd d_max. The present invention is to be noted that the laser beam diameter acting on the surface of the material is not necessarily equal to the width of the pattern after the laser processing, before the chemical treatment, at each stage of the chemical treatment, and after the chemical treatment, but has a one-to-one correspondence relationship. For clarity, unless otherwise specified, the pattern width refers to the pattern width after chemical treatment, and the laser beam diameter refers to the beam waist diameter corresponding to the pattern width. The invention considers that the beam waist diameter range should be selected within the range of 5% -90% of the power of the laser device, and further, the optimal beam waist diameter range should be selected within the range of 10% -80% of the power of the laser device, and the size selection scheme is as follows:

when the pattern width is d ═ d₀The beam waist diameter d is preferably selected_r0Performing single-row/single-row processing;

when the pattern width is d_min≤d≤d_maxThe beam waist diameter d is preferably selected_rmin≤d_r≤d_rmaxPerforming single-row/single-row processing;

when the pattern width d is larger than or equal to d_maxWhen d is satisfied_rmin≤d_r≤d_rmaxUnder the condition of preferentially selecting d_rN is an integer and at a minimum, n x d is satisfied_rAnd d, carrying out widening processing of multiple rows in parallel connection.

The action of lasers and materials is a complex process, related to the type of plastic and the nature of the laser and the energy density and power density of the applied laser. After the plastic absorbs the laser energy, one or more phenomena of temperature increase, melting, vaporization, sublimation, etc. occur, which may cause the plastic to be removed, and may cause the surface morphology of the plastic to change. The method for manufacturing the 3D-MID can be realized by processing of removing the plastic by laser, processing of changing the surface form of the plastic by laser, and combination of two processing of removing the plastic by laser and changing the surface form of the plastic.

The plastic removing process refers to manufacturing pits with certain distribution density and sizes in a certain range in the pattern area by utilizing the function of removing plastic by laser. After activation, compared with the active groups deposited outside the pits, the active groups deposited in the pits have better adhesion with the base material, remain on the base material after debonding, and serve as seeds in the oxidation-reduction process of subsequent chemical plating to initiate the reaction that copper ions are reduced into metal copper, so that a conductive layer pattern is formed; and the active groups deposited outside the pits are desorbed and separated from the base material after the glue is removed, and areas without pits have no active groups, so that no seeds exist in the oxidation-reduction process of the subsequent chemical plating, the reaction that copper ions are reduced into metal copper cannot be initiated, and the copper cannot be deposited to form a conductive layer. As mentioned above, the laser in the infrared frequency band has low photon energy, low coupling degree with plastic, low absorption rate, high transmittance and obvious thermal effect. Therefore, for infrared laser, the processing is realized by a heating mechanism, the processability of most plastics is not good, which is reflected in that larger power is needed, the processed area of the plastic workpiece is remelted due to excessive heating, the micro roughness is low, and the processing performance of the plastic workpiece needs to be improved by virtue of additives in the plastics. The laser of ultraviolet frequency band has high photon energy, obvious photochemical action, high coupling degree with plastic, high absorption rate and low transmissivity. Therefore, even if no additive is added, for ultraviolet laser, high-energy photons can also act on chemical bonds in high polymer molecules to decompose and destroy the structure of the material, the thermal influence is low, the micro roughness of the processed area of the plastic workpiece is high, and the processing performance of most plastics is good. Compared with lasers in infrared and visible frequency bands, ultraviolet lasers are more suitable for removing plastics and manufacturing pits. The effect of material removal, after the laser power exceeds a threshold value of the minimum power required to remove the plastic, depends primarily on the laser energy impinging on the surface of the material. When the pit is manufactured, the laser energy value on the unit area, namely the upper limit and the lower limit of the energy density, are firstly tested to be used as laser processing parameters, and when the beam waist diameter of a laser beam changes along with the width of the conductive pattern, the compensation is carried out by using a laser power control system, so that the laser energy projected on the unit area of the surface of the material is kept stable within the range of the upper limit and the lower limit.

The processing system for 3D-MID mostly adopts a pulse laser source, the pulse duration is fixed and constant, and the energy of the light projected by the laser to a workpiece can be adjusted by controlling the power of the laser. If the default beam waist diameter is d_r0The width of the corresponding pattern is d₀Upper and lower limits of laser projection power, respectively, P, corresponding to the manufacture of appropriate pits_0maxAnd P_0minThe upper and lower limits of the corresponding laser energy value per unit area, i.e., energy density, are w_max(J/cm²) And w_min(J/cm²) (ii) a When the pattern width is d, at this time, the beam waist diameter of the projection laser beam should be changed to d_rAccording to the method of the present invention, the corresponding laser energy value per unit area, i.e. the upper and lower limits of the energy density, should still be w_max(J/cm²) And w_min(J/cm²) But corresponding upper and lower limits P of laser projection power for manufacturing proper pits_maxAnd P_minIt should be [ (1/4) × π × d respectively_r ²]/[(1/4)*π*d_r0 ²]*P_0maxAnd [ (1/4) × π × d_r ²]/[(1/4)*π*d_r0 ²]*P_0minNamely:

P_max＝(d_r/d_r0)²*P_0maxand an

P_min＝(d_r/d_r0)²*P_0min。

The nature of electroless copper plating is that metal deposition is generated under the action of active groups, so that the adhesion and maintenance of the active groups on a substrate and the adhesion of a metal deposition layer to the substrate are the key points for obtaining good electroless copper plating effect. In addition to the fabrication of pits in the substrate, the present invention utilizes a combination of laser processing and chemical treatment to alter the surface state of the substrate and create a more hydrophilic surface with a certain roughness over the patterned areas. As previously mentioned, either chemical treatment or laser machining, if sufficiently intense, can produce a surface on which electroless plating can occur. The invention controls the chemical treatment intensity, so that the area only subjected to chemical treatment can not reach the critical state for initiating chemical plating, but after the chemical treatment is applied to the surface processed by laser, the surface treatment effect and the processing selectivity of the laser processing are added, the effect of the chemical treatment is added, and the area only subjected to two functions simultaneously has the surface state which is suitable for chemical deposition and has good deposition adhesion. In the invention, the area with the surface state has accumulative superposition of two effect effects, after activation, the liquid containing active groups has certain retaining and conserving effects, a layer of liquid film containing active groups is formed on the area, after degumming, enough active groups are still retained, compared with the area which is not processed by laser, the density of the attached active groups is high, and after chemical deposition of metal, a continuous conductive layer can be formed. Moreover, the micro-surface state is rougher in the area because of the one-step laser processing process more than that in other areas, and the chemically deposited conductive metal has greater adhesion with the area. Thus, in the area which is not processed by laser, the attachment density of the active groups is very small, the chemical deposition adhesion is low, a continuous conductive layer cannot be formed, and in the area which is processed by laser, the density of the active groups is high, the deposition effect of the reduced metal ions is good, and the conductive pattern can be ensured to be formed smoothly.

Unlike the mechanism of making pits, the effect of changing the surface state of the plastic is not entirely dependent on the amount of plastic removed, but rather on changing the surface properties of the plastic. In the experimental process, the invention notes that the wavelength and energy of the laser applied to the surface of the material have little correlation with the effect of changing the surface property of the material, but the intensity of the laser light acting on the surface of the material, namely the power of the laser applied to the surface of the material per unit area, plays an important role in changing the surface property of the material. Under the irradiation of high-intensity laser beams generated by ultrashort pulses of picoseconds and femtoseconds, the surface of a workpiece can absorb several or even dozens of photons at the same time, and the multiphoton absorption which is almost generated at the same time can change substances in an acting area, particularly the surface state of a shallow surface although the total energy is not large and the acting depth and the acting volume are small. The plastic high polymer material has relatively complex components and structures, has many mechanisms for changing the properties, can be a main chain, a branched chain or a group in a high polymer, can be changed in components or mutual relation, has a multi-photon absorption effect, and can initiate the change because enough photons simultaneously react with the material to meet the energy of each level required for changing the energy level.

The present invention notes that when the optical power density is sufficiently large, i.e. the number of photons that the beam acts on the material at the same time is sufficiently large, the effect of the multi-photon effect on the processing effect is greater than the effect of the laser frequency on the processing effect. When the infrared laser is used for processing, the pulse width is in picosecond and femtosecond magnitude, although the single-point pulse energy is not high and is between dozens and hundreds of microjoules, the power can reach millions, millions and even hundreds of megawatts. Thus, when the power density exceeds a certain threshold value, a desired processing effect can be obtained by the multiphoton effect. The invention utilizes multiphoton effect, uses picosecond and femtosecond laser to control the laser power value projected to unit area in unit time, namely laser power density or laser intensity, and projects enough photons to unit area in unit time to sublimate and ionize the material, thereby changing the surface property. This means that the material can be processed without incorporation of light-blocking, light-absorbing additives into the plastic. Further, this process is not a conventional hot process, but a sublimation, ionization, micro-removal process that acts only on the surface, which is a cold process.

When the laser changes the surface property of the material, the upper and lower limits of the laser power value in unit area are firstly tried out as laser processing parameters, and when the beam waist diameter of the laser beam changes along with the width of the conductive pattern, the laser power control system is used for compensation, so that the laser power value projected on the unit area of the surface of the material, namely the power density, is kept stable in the range of the upper and lower limits.

Most laser processing systems adjust the power density of the light projected by the laser onto the workpiece by controlling the laser power. If the default beam waist diameter is d_r0The width of the corresponding pattern is d₀Upper and lower limits of laser projection power P for correspondingly changing the surface state of the plastic_0maxAnd P_0minThe upper and lower limits of the corresponding laser power per unit area are I_max(W/cm²) And I_min(W/cm²) (ii) a When the pattern width is d, at this time, the beam waist diameter of the projection laser beam should be changed to d_rAccording to the method of the present invention, the upper and lower limits of the corresponding laser power per unit area should still be I_max(W/cm²) And I_min(W/cm²) The upper and lower limits P of the laser irradiation power for correspondingly changing the surface state of the plastic_maxAnd P_minShould be respectively [ (1/4) × π × d_r ²]/[(1/4)*π*d_r0 ²]*P_0maxAnd [ (1/4) × π × d_r ²]/[(1/4)*π*d_r0 ²]*P_0minNamely:

P_max＝(d_r/d_r0)²*P_0maxand an

P_min＝(d_r/d_r0)²*P_0min。

In the existing laser processing equipment, in the working distance, an optical system of the existing laser processing equipment is generally designed with only one beam diameter, and when a larger beam diameter is needed, an operator often processes the existing laser processing equipment in a state of deviating from the beam waist position of a focused beam by changing the working distance. The processing deviating from the laser focal plane is easy to cause the processing to be carried out in a range exceeding the effective action range of the laser beam, the position sensitivity is very high, and the control is difficult. The negative effects of the precision of the equipment and the flatness of the material surface can be amplified outside the effective processing range of the laser beam, which can cause great changes of the projected energy density and power density, even cause the position deviation of the projected laser and influence the processing consistency, and is one of the causes of quality defects.

The optical system of the device is provided with the beam expanding lens with variable multiples, and the diameter of the beam waist of the condensed laser beam is changed by changing the beam expanding times. In the processing process, the equipment data processing system and the control system select a proper beam waist diameter D according to the size of each pixel in the processed pattern under the condition of keeping the laser energy density and the power density unchanged, and the beam expansion control system changes the beam expansion multiple to generate a beam with the diameter D corresponding to the beam waist diameter, so that the change of the beam waist diameter is completed. The diameter of the expanded output beam is related to the diameter of the waist of the focused beam by the following equation:

d＝(4/π)*λ*(f/D)*M²+β*(D³/f²)

wherein d is the diameter of the beam waist of the focused beam, lambda is the laser wavelength, f is the focal length of the focusing lens, and M is the focal length of the focusing lens²For laser beam quality parameters, β is a spherical aberration refractive index function, which is related to wavelength, lens structure/shape, material.

The invention has the advantages and beneficial effects that:

compared with the prior art that only the defocusing method can be adopted to change the diameter of the light beam acting on the surface of the material, the technical scheme of the invention keeps the energy density and the power density unchanged, changes the beam expansion multiple on line to change the beam waist diameter of the light beam and change the working distance with the surface of the material along with the size of the processed pattern, optimized processing parameters and processing data, ensures that the processing process of the interaction of the laser and the material is carried out within the Rayleigh length of the light beam, has large effective processing range, good processing consistency, high processing speed and accurate pattern size after processing.

Drawings

FIG. 1 is a schematic view of a laser apparatus according to embodiment 1;

in the figure: the laser processing device comprises a laser source 1, a laser beam 2, an electric beam expander 3, an AOD4, a scanning galvanometer 5, a telecentric lens 6, a workpiece 7, a worktable 8, a control motor 9, a galvanometer processing range 10, an AOD processing range 11, data 12, a computer 13, a laser control card 14 and a motion controller 15.

FIG. 2 is a schematic diagram of a laser apparatus according to embodiment 2;

in the figure: the laser system comprises a laser light source 1, a laser beam 2, an electric beam expander 3, a dodging DOE4, a scanning galvanometer 5, a telecentric lens 6, a worktable 7, a workpiece 8, a control motor 9, a Gaussian beam 10, a flat-top beam 11, data 12, a computer 13, a laser control card 14 and a motion controller 15.

FIG. 3 is a schematic diagram of a laser apparatus according to embodiment 3;

in the figure: the laser system comprises a laser source 1, a laser beam 2, a beam expander 3, an AOD4, a polygon mirror 5, a focusing original 6, a workpiece 7, a transmission mechanism 8, a transmission motor 9, data 10, a computer 11, a laser control card 12 and a motion controller 13.

FIG. 4a shows a first pattern used in examples 1 and 2;

FIG. 4b shows a second pattern used in examples 1 and 2;

FIG. 5 is the pattern used in example 3;

FIG. 6 is the overall appearance of the sample of example 1;

fig. 7 is a picture of a sample magnified 1000 times.

Detailed Description

The invention will be further described below with reference to three embodiments. The following examples are illustrative and not intended to be limiting, and are not intended to limit the scope of the invention.

Example 1:

an apparatus having a variable power beam expanding system is used to make conductive patterns on an ABS substrate.

(1) And determining the upper limit of the chemical processing parameter of the ABS material and the lower limit of the laser processing intensity.

Starting from the ABS plastic chemical plating process conditions, firstly, the chemical treatment step of one process is confirmed: oil removal, pre-soaking, activation, dispergation and chemical copper deposition. In this embodiment:

the oil removal is preferably carried out by using an alkaline oil removal agent, and the solution comprises the following components: 15g/L of sodium carbonate, 30g/L of sodium phosphate, 50g/L of sodium hydroxide and 2g/L of surfactant, wherein the temperature is 50-80 ℃, and the time is 5-10 min.

Pre-dipping, activating and dispergating, wherein the pre-dipping solution comprises the following components: hydrochloric acid of 200ml/L at room temperature for 1-3 min; the composition of the activated solution was: 0.05g/L of palladium chloride, 10g/L of stannous chloride, 200ml/L of hydrochloric acid and 50g/L of sodium chloride, wherein the temperature is 25-35 ℃, and the time is 1-5 min; the dispergation solution consists of: the ethanol UDIQUE 8812ACCELERATOR is 250ml/L, the temperature is 40-55 ℃, and the time is 2-10 min.

③ the embodiment preferably uses alkaline chemical copper deposition solution, and the solution composition is: 13-17 g/L of copper chloride, 30-40 g/L of disodium ethylene diamine tetraacetate, 10-15 g/L of sodium hydroxide, 10-14 ml/L of 37% formaldehyde, 0.05g/L of alpha, alpha' -bipyridine, 0.01g/L of potassium ferrocyanide, 12-13 of pH value, 30-45 ℃ of temperature and 10-150 min of time.

In these several steps, the activation and dispergation effect on the activity is greatest, and for the sake of process simplification, only the dispergation time is adjusted to change the activity. With the other parameters fixed, the disperging was increased from 2min to 5min stepwise, and the surface that had not been laser machined began to deposit no copper. This is taken as the upper limit of the chemical treatment, i.e. the dispergation time should not be less than 5min without changing other parameters.

In this embodiment, an ultraviolet picosecond laser machine is preferably used for laser processing. The equipment is provided with a zooming and beam expanding system and other systems such as an AOD system and the like to improve the processing efficiency, and the equipment schematic diagram is as shown in figure 1: the laser beam 2 is emitted from the laser source 1, sequentially passes through the electric beam expander 3, the AOD4, the scanning galvanometer 5 and the telecentric lens 6, and then reaches the surface of the workpiece 7.

Under the condition that other parameters are not changed (the initial beam expansion multiple is 3 times), in order to simplify the process, the output power of the laser is only adjusted to change the laser processing intensity, the power percentage is increased from 2 percent (3w) until the power reaches 8 percent (12w), and copper deposits (observed by a magnifier of 100-1000 times) are formed on more than 95 percent of the area of a laser processing area. This is used as the lower limit of the laser processing intensity.

(2) The lower limit of the chemical treatment parameters and the upper limit of the laser processing intensity are determined.

In the present embodiment, the upper limit of the laser processing intensity is 100% (150 w).

Under the condition that other parameters are unchanged, the glue-stripping time is increased from 5min until 8min, and the phenomenon of plating leakage of the laser processing area begins to occur. This is taken as the lower limit of the chemical treatment.

(3) And determining chemical treatment parameters and laser processing parameters.

From the cross experiment of the upper and lower limits of chemical treatment and laser processing, the optimal parameters are finally confirmed, other parameters are unchanged, the dispergation time is 6min, and the laser power is 9% (13.5 w).

(4) And testing the processing result to establish the corresponding relation between the pattern size and the beam waist diameter.

In this embodiment, the beam waist diameter d corresponding to the variable beam expander_rThe range of (7.5-45.2 um) is set to 5 kinds of d_rAnd (4) carrying out a separate experiment, calculating the optical power P with the corresponding proportion by taking the optical power density finally obtained in the step (3) as a constant, and finally measuring 5 corresponding minimum widths d of the coating layers. Measured d_rData d, P are as follows:

beam waist diameter d_r/um：	7.5	9	15	22.6	45.2
						Multiple of beam expansion	6	5	3	2	1
Laser power P/w	3.38	4.86	13.5	30.65	122.58
						Minimum line width d/um after plating	13.5	15	24	30	53

(5) And according to the conductive pattern structure, generating parameters and processing data of the laser corresponding to the processing task by taking the beam waist diameter as a variable and taking the energy and the power on a unit area as constant.

The patterns used in this example are shown in FIGS. 4a and 4b

In this embodiment, the laser machine is used for single line processing of d_min＝13.5um，d_max53 um; corresponding d_rmin＝7.5um， d_rmax45.2 um. Selecting a pattern with a minimum line width d₀>d_min。

When the pattern width is d_min≤d≤d_maxWhen is at d_rmin～d_rmaxPreferentially selecting the diameter dr of the beam waist of the corresponding light beam in the range to carry out single-line/single-line processing;

when the pattern width d is larger than or equal to d_maxWhen d is satisfied_rmin≤d_r≤d_rmaxUnder the condition that d is preferred_r，d_rIs d₁D corresponding to d/n_rWherein n ═ d/d_max]+1, performing widening processing of multiple parallel lines.

In this embodiment, 10 patterns with different line widths are used, and data processing software, circuit cam 7, of the delad middle technology development corporation is used to simulate laser processing, so as to obtain the required beam expansion multiple classification. And then generating a machining path file according to the classification.

The device driver software DreamRefeTor 3 of the Dezhong (Tianjin) technology development Limited company is used for setting operation parameters on the laser machine to generate 5 parameters

(6) And carrying out laser processing.

This example uses an ultraviolet picosecond (wavelength 355nm) laser for processing. And fixing the sample by using a jig, and scanning once to finish processing.

(7) Chemical treatment is carried out.

And (3) putting the sample subjected to laser processing into an oil removing groove to remove oil, wherein the oil removing temperature is 70 ℃, and the time is 10 min. Washing with water, and placing into a pre-soaking tank at normal temperature for 1 min. Directly placing into an activation tank after pre-soaking, and keeping the temperature at 32 ℃ for 3 min. Activating, standing in pure water for 2min, washing with water, and dispergating in dispergation tank at 46 deg.C for 6 min. Washing with water, and precipitating copper in a copper precipitation tank at 38 deg.C for 150 min.

(8) And checking, measuring and evaluating the processing result.

The sample has no plating leakage and no over plating, the line width error is within 5 percent, and the result of the hundred-grid test is 5B.

Example 2:

conductive patterns were made on ABS + 40% PC substrates using a device with a variable power beam expansion system with a DOE system.

(1) The upper limit of the chemical processing parameters of the ABS + 40% PC material and the lower limit of the laser processing intensity are determined.

The ABS + PC material has similar chemical properties with ABS material, and the plastic chemical plating process has similar process steps with ABS, specifically: degreasing, chemical roughening, presoaking, activating, dispergating and chemical copper deposition. In the examples:

The chemical roughening solution comprises the following components: 220ml/L of sulfuric acid, 65-80 ℃ and 10-30 min.

③ presoaking, activating and dispergating, wherein the presoaking solution comprises the following components: hydrochloric acid of 200ml/L at room temperature for 1-3 min; the composition of the activated solution was: 0.05g/L of palladium chloride, 10g/L of stannous chloride, 200ml/L of hydrochloric acid and 50g/L of sodium chloride, wherein the temperature is 25-35 ℃, and the time is 1-5 min; the dispergation solution consists of: the ethanol UDIQUE 8812ACCELERATOR is 250ml/L, the temperature is 40-55 ℃, and the time is 2-10 min.

The embodiment preferably uses alkaline chemical copper deposition solution, and the solution composition is as follows: 13-17 g/L of copper chloride, 30-40 g/L of disodium ethylene diamine tetraacetate, 10-15 g/L of sodium hydroxide, 10-14 ml/L of 37% formaldehyde, 0.05g/L of alpha, alpha' -bipyridine, 0.01g/L of potassium ferrocyanide, 12-13 of pH value, 30-45 ℃ of temperature and 10-150 min of time.

In these several steps, the activation and dispergation also have the greatest effect on the activity, and for the sake of process simplification, only the dispergation time is adjusted to change the activity. With the other parameters fixed, the disperging was increased from 2min to 4min stepwise, and the laser-unprocessed surfaces began to deposit no copper. The upper limit of the chemical treatment is taken as the upper limit, namely the degumming time is not less than 4min under the condition that other parameters are not changed.

An ultraviolet picosecond laser machine is preferably used for laser machining in this embodiment. The device is provided with a zooming and beam expanding system and other systems such as a DOE system and the like to shape the light beam, and the device is schematically shown in figure 2: the laser beam 2 is emitted from the laser light source 1, sequentially passes through the electric beam expanding lens 3, the uniform light DOE4, the scanning galvanometer 5 and the telecentric lens 6, and then reaches the surface of the workpiece 7.

Under the condition that other parameters are not changed (the initial beam expansion multiple is 3 times), in order to simplify the process, the output power of the laser is only adjusted to change the laser processing intensity, the power percentage is increased from 2 percent (3w) until the power reaches 32 percent (48w), and copper deposits (observed by a magnifier of 100-1000 times) are formed on more than 95 percent of the area of a laser processing area. This is used as the lower limit of the laser processing intensity.

Under the condition that other parameters are unchanged, the glue dissolving time is increased from 4min until the beginning of 17min, and the plating leakage of the laser processing area occurs. This is taken as the lower limit of the chemical treatment.

From the cross experiment of the upper and lower limits of chemical treatment and laser processing, the optimal parameters are finally confirmed, other parameters are unchanged, the dispergation time is 15min, and the laser power is 36% (54 w).

Beam waist diameter d caused by using a variable magnification beam expander in this embodiment_rThe range of (15-90.4 um) is set to 5 kinds of d_rAnd (4) carrying out a separate experiment, calculating the optical power P with the corresponding proportion by taking the optical power density finally obtained in the step (3) as a constant, and finally measuring 5 corresponding minimum widths d of the coating layers. Measured d_rData d, P are as follows:

beam waist diameter d_r/um：	15	18	30	45.2	90.4
						Multiple of beam expansion	6	5	3	2	1
Laser power P/w	13.48	19.44	54	122.6	—
						Minimum line width d/um after plating	20	22	36	54

The patterns used in this example are shown in FIGS. 4a and 4b

In this embodiment, the laser machine is used for single line processing of d_min＝20um，d_max54 um; corresponding d_rmin＝15um， d_rmax45.2 um. Selecting a pattern with a minimum line width d₀>d_min。

(6) And carrying out laser processing.

(7) Chemical treatment is carried out.

And (3) putting the sample subjected to laser processing into an oil removing groove to remove oil, wherein the oil removing temperature is 70 ℃, and the time is 10 min. Washing with water, and roughening in a chemical roughening tank at 68 deg.c for 10 min. Repeatedly washing with water, cleaning, and reducing in a reduction tank at normal temperature for 5 min. Washing with water, and placing into a pre-soaking tank at normal temperature for 1 min. Directly placing into an activation tank after pre-soaking, and keeping the temperature at 32 ℃ for 3 min. Standing in pure water for 2min after activation, washing with water, and dispergating in dispergation tank at 46 deg.C for 15 min. Washing with water, and precipitating copper in a copper precipitation tank at 38 deg.C for 150 min.

(8) And checking, measuring and evaluating the processing result.

The sample has no obvious plating leakage and overflow, the line width error is within 6 percent, and the result of the Baige test is 4B.

Example 3:

this case uses two laser devices working together, where a small spot of uv nanosecond has both AOD and Polygon Scanner systems to improve the processing efficiency.

(1) The upper limit of the chemical treatment parameters of the LCP material and the lower limit of the laser processing intensity are determined.

In the step, the activity was also changed by adjusting only the gel-breaking time. With the other parameters fixed, the disperging was increased from 2min to 5min stepwise, and the surface that had not been laser machined began to deposit no copper. Taking the upper limit of the chemical treatment as the upper limit, namely the dispergation time is not less than 5min under the condition that other parameters are not changed.

The LCP material sheet processed by using one laser light source has poor bonding force. In this embodiment, the processing is performed in an infrared picosecond + ultraviolet nanosecond manner. Infrared picosecond processing is used to change the surface state of the processed area, and then ultraviolet nanosecond processing is used to interact with LCP materials more easily. The DirectLaser S2 Infrared picosecond and DirectLaser S5 ultraviolet nanosecond lasers manufactured by Texas technology development, Inc. are preferred in this example. Wherein the ultraviolet nanosecond has both AOD and Polygon Scanner systems, and the schematic diagram of the device is shown in FIG. 3: the laser beam 2 is emitted from the laser light source 1, sequentially passes through the beam expander 3, the AOD4, the polygon mirror 5 and the focusing element 6, and then reaches the surface of the workpiece 7.

Under the condition that other parameters are not changed, in order to simplify the process, the output power of the ultraviolet sodium second laser is only adjusted to change the laser processing intensity, the power percentage is increased from 5 percent (2.5w) until the power reaches 30 percent (15w), and copper is deposited on more than 95 percent of the area of a laser processing area (observed by a magnifying glass of 100-1000 times). This is used as the lower limit of the laser processing intensity.

In this example, the upper limit of the laser processing intensity is 100% (50 w).

Under the condition that other parameters are unchanged, the glue-stripping time is increased from 5min until 9min, and the phenomenon of skip plating of the laser processing area begins to occur. This is taken as the lower limit of the chemical treatment.

From the cross experiment of the upper and lower limits of chemical treatment and laser processing, the optimal parameters are finally confirmed, other parameters are unchanged, the dispergation time is 8min, and the laser power is 30% (15 w).

The minimum line width after plating in this example is 48um and the minimum line width of the pattern in this example is 150um, subject to the limitation of infrared picosecond pre-processing.

(4) And carrying out laser processing.

The pattern adopted in this embodiment is as shown in fig. 5, has 4 different line widths, and a processing path file is generated by using a data processing software circuit cam 7 of the limited dividend corporation of the technology development of delaunay (tianjin).

The device driver software DreamRefeTor 3 of Dezhong (Tianjin) technology development Limited is used for setting the operating parameters on the laser machine to generate 1 parameter

The laser processing parameters of infrared picoseconds and ultraviolet nanoseconds are as follows:

(5) chemical treatment is carried out.

And (3) putting the sample subjected to laser processing into an oil removing groove to remove oil, wherein the oil removing temperature is 70 ℃, and the time is 10 min. Washing with water, and placing into a pre-soaking tank at normal temperature for 1 min. Directly placing into an activation tank after pre-soaking, and keeping the temperature at 32 ℃ for 3 min. Activating, standing in pure water for 2min, washing with water, and dispergating in dispergation tank at 46 deg.C for 8 min. Washing with water, and precipitating copper in a copper precipitation tank at 38 deg.C for 150 min.

(6) And checking, measuring and evaluating the processing result.

The sample has no plating leakage and no over plating, the line width error is within 5 percent, and the result of the hundred-grid test is 4B.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various changes and modifications can be made without departing from the inventive concept, and these changes and modifications are all within the scope of the present invention.

Claims

1. A system for selectively activating insulating materials to manufacture conductive patterns by combining laser and chemistry comprises a data acquisition and processing system, an equipment operation system, a laser light source, a light beam shaping and transmission system, a laser focusing system, a workpiece clamping and workpiece rotating and overturning system, a workpiece and light beam movement and control system, a positioning and detection visual system, a laser power monitoring and compensating system and a cleaning and constant temperature system, and is characterized in that: according to the circuit pattern structure, energy and power in unit area are used as constant quantities, different beam waist diameters are matched, optimized processing parameters and processing data are generated, and the beam diameter of interaction between the laser and the material can be converted on line under the condition that the energy and the power in unit area are constant at set values, so that processing is carried out.

2. The system of claim 1, wherein: the data acquisition and processing system selects the beam waist diameter d according to the following rules:

when the pattern width d is larger than or equal to d_maxWhen d is satisfied_rmin≤d_r≤d_rmaxUnder the condition of preferentially selecting d_rN is an integer and at a minimum, n x d is satisfied_rD, carrying out multi-row parallel continuous widening processing;

the laser energy density is determined according to the following rules:

P_max＝(d_r/d_r0)²*P_0maxand an

P_min＝(d_r/d_r0)²*P_0min；

The laser power density is determined according to the following rules:

P_max＝(d_r/d_r0)²*P_0maxand an

P_min＝(d_r/d_r0)²*P_0min；

Wherein: d is the width of the pattern after chemical treatment, d_rIs the laser beam waist diameter corresponding to a pattern width d; d₀Is the width of the pattern after chemical treatment under default/default conditions, d_r0A default beam waist diameter for the laser device corresponding to the default pattern width; d_maxAnd d_minAre respectively asProcessing the maximum and minimum values of the chemically treated pattern width with the apparatus-adjustable maximum and minimum diameter beams, d_rmaxAnd d_rminThe device is respectively the adjustable maximum laser beam waist diameter and the adjustable minimum laser beam waist diameter; p_0maxAnd P_0minRespectively, the beam waist diameter of the laser beam is d_r0Manufacturing the maximum power and the minimum power allowed by the base material when the proper pits are manufactured; p_maxAnd P_minRespectively, the beam waist diameter of the laser beam is d_rThe maximum and minimum power allowed by the substrate when the appropriate pit is made.

3. The system of claim 1, wherein: the laser light source parameter range is as follows: wavelength: 266nm-10700 nm; pulse width: 10fs-1000 mus; pulse repetition rate: 1KHz-100 MHz; average power: 1W-10000W.

4. The system of claim 1, wherein: the operation, control and drive of multiple systems use computer and communication system composed of the same circuit board, or use computer and communication system composed of multiple circuit boards.

5. The system of claim 1, wherein: the data acquisition and processing system and the equipment operating system are respectively two independent software packages and use different user interfaces; or as a software package, using the same user interface.

6. The system of claim 1, wherein: the beam shaping and transmitting system includes an optical processing system for expanding or reducing the beam waist diameter of the laser beam by using an optical device and for uniformly distributing the light energy on a cross section perpendicular to the transmitting direction of the light energy.

7. The system of claim 1, wherein: the beam shaping and transmission system is a diffractive optical element/DOE, an electro-optic modulation device/EOD, an acousto-optic modulation device/AOD, a Polygon scanning device/Polygon Scanner, a Resonant scanning device/resonance Scanner, a galvanometer Scanner/Galvanic Scanner, a piezoelectric and micro-electromechanical Scanner/Piezo-MEMS Scanners, a micro-Scanner/micro-Scanner and a digital micro-mirror device/DMD which are used singly or in a mixed way.

8. The system of claim 1, wherein: the focus of the laser focusing system changes along with the Z direction when the three-dimensional workpiece curved surface is processed, so that the light beam keeps a focusing state on the processed surface and is vertical to the processed surface.

9. The system of claim 1, wherein: the positioning and detecting vision system comprises a camera system for identifying, checking and measuring the workpiece and the pattern characteristic structure on the workpiece, and an illuminating light source capable of dynamically matching the texture, texture and color of the material; the system also includes optical and mechanical structures for projecting the machining laser beam onto the workpiece at a determined location; the system also comprises software for driving and controlling the photographing, lighting and positioning motions, and data acquisition, processing and output software for identification, inspection, measurement and positioning.

10. The system of claim 1, wherein: the laser power monitoring and online compensating system comprises a laser power meter arranged on a working table and a control system for adjusting the output power of the laser according to the laser power of the working table.

11. The system of claim 1, wherein: the cleaning and constant temperature system is controlled by an equipment operating system, wherein the constant temperature system is arranged in the equipment or at the top end of the equipment; the cleaning function is realized by a blowing and dust-absorbing system, wherein an air suction port of the dust-absorbing system is closer to a workpiece and is positioned at the lower part of the processing head, an air inlet with a filter screen and a cross section smaller than the sectional area of the air suction port is arranged at the position, which is opposite to the horizontal height of the air suction port, of the lower part of the processing head, an air blowing port of the blowing system is closer to the optical protective mirror and the focusing mirror and is positioned at the middle upper part of the processing head, the horizontal position is higher than the air suction port, an air exhaust hole with the filter screen is arranged at the position, which is opposite to the air blowing port and is the same as the horizontal height of the air blowing port, of the middle part of the processing head, and the air suction port and the air blowing port are arranged at the same side of the processing head or in opposite directions; the blowing and sucking modes can be started simultaneously or alternately and alternately according to the processing progress, the mode comprises a sucking mode when materials are removed, and the blowing mode is switched after the materials are cut completely or drilled completely to form a cutting or drilling starting point.