CN113560736A

CN113560736A - Method for manufacturing conductive pattern by using laser to selectively activate insulating material

Info

Publication number: CN113560736A
Application number: CN202110746551.2A
Authority: CN
Inventors: 王恒亮; 胡宏宇
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 method for manufacturing a conductive pattern by using laser to selectively activate an insulating material, which comprises the steps of carrying out surface adjustment on the insulating material to enable the surface to be in a state which is not beneficial to depositing an activating agent; setting specific processing path and laser parameters to form micro pits in certain arrangement on the surface after laser processing, wherein any two pits cannot be overlapped, and selectively processing the surface of the substrate by laser according to an electronic pattern to selectively destroy the adjusted surface state. Placing the substrate in an activating solution to accumulate the surface modification and pitting effects, resulting in selective deposition of the activating agent on the laser-machined site; and (3) placing the substrate in chemical plating solution to deposit a metal layer, and forming a metal circuit with an electronic pattern on the surface of the substrate after the deposition is finished. The invention can be applied to finer circuits because the surface adjustment is performed in advance, the problem of overflow plating is better controlled. The micro pit structure after laser processing can ensure enough binding force between the metal layer and the substrate even if chemical coarsening is not used.

Description

Method for manufacturing conductive pattern by using laser to selectively activate insulating material

Technical Field

The invention belongs to the field of insulating materials, relates to a 3D-MID (three-dimensional-intermediate device) manufacturing technology of a conductor structure, and particularly relates to a method and a component for selectively forming an electronic pattern on an insulating material.

Background

As the integration of electronic devices increases, the size of the devices becomes smaller, and the electronic components become too large for the entire device, which requires a reduction in size. Size reduction while not significantly affecting the functionality and efficiency of electronic components is a challenge in the development of electronic devices, and 3D-MID technology is a class of technologies that can better address this challenge.

3D-MID is an abbreviation for "Three-dimensional structured Interconnect Device" in English, which is interpreted in Chinese as a Three-dimensional molded Interconnect Device or electronic component. Has been developed into the English "Three-dimensional mechanical integrated device", i.e. Three-dimensional electromechanical integrated device. The prior art relates to insulating materials including but not limited to plastics, so that the three-dimensional electromechanical integrated device is more accurate.

The 3D-MID technology is to fabricate a lead and a pattern having an electrical function on a housing made of an insulating material, and fabricate or mount components, so as to integrate the electrical interconnection function, the function of supporting the components, the support and protection functions of the housing, and the shielding and antenna functions generated by the combination of a mechanical entity and the conductive pattern into a whole, thereby forming a so-called three-dimensional electromechanical integrated device.

Compared with the Stereolithography/STL (Stereolithography/STL), Fused Deposition Modeling (Fused Deposition Modeling/FDM) or 3D Printing (3D-Printing), the 3D-MID technology has the characteristics that: on the basis of manufacturing (AM) mechanical structural parts by an additive manufacturing method, an innovative dimension is added, and the AM mechanical structural parts have mechanical functions and electrical functions and are intelligent device (part) parts.

The 3D-MID has various production processes, and the process with wider application range comprises the following steps:

1. the LDS process of Germany LPKF company, namely the laser direct forming process, comprises the following steps: (1) the workpiece is subjected to one-time injection molding (2) and the laser activation circuit part (3) is subjected to electroless copper plating. The method has the advantages of mature process, material and equipment, and is the mainstream technology for manufacturing the antenna. The disadvantages are the use of modified substrates, which are expensive and which have an impact on the chemical, mechanical and electromagnetic stability of the substrate.

2. The two-component plastic process, SKW-MID, of the company Sankyo Kasei in Japan, namely a two-step injection molding process, comprises the following steps: (1) the non-circuit part of the workpiece is formed by common plastic injection molding (2) the circuit part is formed by easily-plated plastic injection molding (3) copper is chemically plated only on the circuit part. The advantage is that no special material is used. The disadvantages are long period, high cost, not fine circuit, and only suitable for mass production.

3. The laser selective resist removing method of Japan Songsu comprises the following steps: (1) the injection molding (2) of the workpiece is carried out, the chemical copper plating (3) is carried out on the workpiece, a corrosion inhibitor (4) is coated, the corrosion inhibitor (5) is selectively removed by laser, and the surface treatment/nickel plating, gold plating and the like of the conductive structure (6) are formed by etching. The method has the advantages that common materials are used, and the process is relatively stable. The defects are that the process is complex, the flow is long, the method is not suitable for complex workpieces, and the process is not environment-friendly.

Emerging processes are:

1. an AJ/Aerosol Jet process of OPTOMEC company in America, namely a process for directly spraying and printing a conductive material in an Aerosol state, comprises the following steps: (1) and (3) performing injection molding on the workpiece, and (2) spraying and printing the aerosol coating (3) and sintering by using a xenon lamp or laser or an oven. Its advantages are wide application range and high effect on ceramic. The disadvantages are high energy consumption and relatively high requirements for the heat resistance of the material.

2. Plasma Innovations Plasma coating process of austria company, a method of coating conductive material with Plasma at low temperature + fine + normal pressure, direct writing conductive structure: the arc between the anode and cathode generates a plasma jet whose energy melts the incoming copper particles, which are sprayed onto the substrate, directly forming a conductive structure. Its advantages are short process and wide application range. The disadvantage is that the circuit is not fine enough.

Patent CN1518850A describes a conductor track structure and a method of manufacturing (LDS) thereof. The conductor track structure is composed of a metal crystal nucleus and a metallization layer subsequently applied to the metal crystal nucleus. The conductor track structure is located on a non-conductive carrier material, which is doped with a non-conductive metal compound. Irradiating the area of the carrier material, in which the conductor track structure is to be generated, with electromagnetic rays, separating heavy metal crystal nuclei from the doped non-conductive metal compound, and then chemically reducing and metallizing the area; while the non-illuminated areas remain unchanged. This allows the conductor track structure to be produced on a non-conductive carrier material. However, the disclosed method is costly. Firstly, for the production of the conductor track structure, the non-conductive metal compound incorporated in the non-conductive support material is a highly thermally stable, stable and insoluble in aqueous acidic or alkaline metallated electrolytes, a non-conductive spinel-based higher-order oxide or a simple spinel-like d-metal oxide or a mixture thereof, whereby the non-conductive metal compound is known to be structurally demanding and expensive; secondly, the cost of the bearing material capable of being doped with the non-conductive metal compound is high, and a certain limitation is also caused.

Therefore, the LDS process needs special materials, and metal compounds required by the LDS process are added into the materials, and due to the fact that the adding proportion is large, the modified materials have large influences on the aspects of thermal stability, compatibility, plasticizing stability, electrical property stability and the like of the metal compounds and plastic base materials, the cost is improved, and meanwhile the application range of the materials is limited.

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 substrate", CN103477725A "harmless technology for establishing continuous conductive circuit on surface of non-conductive substrate" disclose technical schemes for making conductive structure on insulating material by addition method, these methods are based on general plastic chemical plating and electroplating technology, after activating workpiece globally and performing chemical plating processing, removing active metal group added on insulating material surface by laser along outer envelope line of required conductive pattern, or removing chemical plating deposition metal layer on insulating material surface and active metal group below by laser along outer envelope line of required conductive pattern, so as to make required conductive pattern electrically insulated from non-pattern area, becoming 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 of the conductive pattern area is greater than that of the conductive layer of 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 methods such as differential etching and the like to obtain the product.

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 incorporated, 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.

In general, there are roughly three types of 3D-MID process technologies using laser processing: (1) active materials are doped in plastics, laser selective processing is carried out, only active groups in the conductive pattern area are released, and then regional chemical plating is carried out, so that the technical base material is high in cost, and compared with the base material without the active materials, the base material has the advantages that the chemical, physical, electrical and other properties can be changed; (2) global activation and chemical plating, wherein a conductive material is removed by laser, and the surface of a workpiece is electrically partitioned, local electroplating and the like, and the technology needs chemical roughening of the surface of an insulating material, belongs to a semi-reduction method and has large environmental burden; (3) the use of lasers for direct or indirect roughening of the conductive pattern areas and the selective application of conductive materials by lasers, which methods, while being aware of the effect of roughening on adhesion, still have technical problems to be solved, in particular with regard to the selection of laser parameters, and require more information that can be quantified and implemented.

Disclosure of Invention

The present invention provides a method for laser selective activation and metallization of an insulating material. It is proposed to first make adjustments to the substrate surface that are detrimental to the deposition of the activator. Then, the laser processing process is refined, and more precise requirements are provided for the surface state, the roughness and the effect expression of the processed base material. The two effects of the difference in surface conditioning and pitting are controlled and accumulated to make activation selective. And finally, carrying out chemical plating, wherein metal is deposited on the laser-processed part of the surface of the substrate, and metal is not deposited on the unmachined part, so that an electronic pattern metal circuit is formed.

The method provided by the invention can be used for more clearly determining the surface state after laser processing. The processed pattern is finer, and the control of the excessive plating and the plating leakage is better. The steps of chemical coarsening and the like which have large influence on the environment can be omitted, so that the method is more environment-friendly. The process steps are shown in figure 1, the flow is simple and clear, and the cost is low.

The experimental equipment can be matched with different beam waist diameters to generate optimized processing parameters and processing data according to a circuit graph structure and by taking energy and power in unit area as constant quantities in online processing. The processing consistency is good, the metallized circuit is more accurate, the processing speed is high, the parameters and indexes are specific, and the process is controllable.

The method comprises the following specific steps:

(1) the insulating material is surface conditioned.

Different materials react differently to the deposition of the activator, resulting in different deposition effects under the same conditions, and thus, surface conditioning may be different. For example, ABS material has a stronger adsorption effect on colloidal palladium than PC material. In the step, after the surface of the material is adjusted, all the surfaces are not beneficial to the deposition of the activating agent, the laser processing carries out remelting, gasification and sublimation on one layer of the surface of the material, the surface adjustment state of a processed part is damaged, the processed part is easier to deposit the activating agent than an unprocessed part, and thus, a certain degree of selectivity can be generated in the step of depositing the activating agent.

The surface modification method may be a chemical reaction, a physical reaction, or a combination of both reactions. For example, a relatively representative activator is colloidal palladium, which in solution has the form of an outermost layer of palladium atoms that are chloride ions and surrounded by stannous, and the surface of the colloidal particles is negatively charged (as shown in fig. 7). The surface adjustment treatment can select corona to make the surface of the material have negative charges, and the colloidal palladium is difficult to deposit on the surface of the material according to the principle that like charges repel each other; or carrying out chemical reaction to make the material surface have a functional group with negative charge; it is also possible to first chemically react and then corona treat to enhance the surface negative charge. Regardless of the surface conditioning treatment used, the net effect is that the treated material surface will deposit less or no palladium compared to the untreated material under the same conditions. Different materials have different chemical and physical properties, so the surface treatment effect of the same surface adjustment treatment method is not always the same in different materials.

The surface of the insulating material can be coated with a coating, and the coating with the function of activating liquid dredging can be liquid water-based or oil-based, and can also be suspension. The solvophobic properties of the coating are critical to achieving activator selectivity, so coating integrity is critical. Whether dipping, spraying, coating, etc. are used, it is necessary to ensure that the surface of the material is completely covered with the coating.

In the metallization process after laser processing, there are not exactly the same process steps, such as degreasing, pre-dipping, sensitization, activation, de-gumming, electroless copper plating, etc., depending on the substrate. The chemical liquid used in these process steps has a certain acidity or alkalinity, so the coating layer has a certain acid resistance or alkali resistance or acid and alkali resistance according to the specific process steps.

The effect of the metallization after surface conditioning and without surface conditioning was compared under the same conditions as in fig. 3a and fig. 3 b.

(2) And setting a processing path and laser parameters.

The interaction of light with matter, which is essentially the absorption or radiation of photons by microscopic particles that make up the matter, changes the behavior of its own motion. The microparticles each have a specific set of energy levels (typically these energy levels are discrete). The particles can only be in a state corresponding to a certain energy level at any one time. Upon interaction with a photon, the particle transitions from one energy level to another and absorbs or radiates the photon accordingly.

The photon energy required by covalent bond breakage and molecule vaporization sublimation among different materials is different, so the influence degree of the same laser power density on different materials is different, and the size of a pit formed after a laser single pulse or a pulse train reacts with the materials is different.

Before the laser processes the material according to the electronic pattern, the size of the pit processed by the laser single pulse or pulse train needs to be tested, and then a specific processing path and laser parameters are set for the material according to the test result, so that the micro pits in a certain arrangement are formed on the surface of the substrate after the laser processing.

The pits have a certain conservation effect on liquid, more activating agents are easy to deposit, and the metal in the pits after metallization has the effect of anchor points, so that the bonding force between the metal layer and the base material can be improved. If two pits are overlapped, the pit wall disappears, so that the conservation effect on liquid is lost, and the bonding force after metallization is poor; if the distance between the two pits is too large, anchor points are reduced, the binding force is also worsened, and plating leakage is easily caused. Therefore, a certain processing path and laser parameters need to be set, so that the pits processed by the laser have proper intervals.

For example, the material A has a pit diameter d after a certain laser single pulse or pulse train processing at a fixed power density_min. The line spacing of the processing lines generated by the CAM software and the spacing between single pulses or pulse strings set by the operating software on the laser are set as d, and the d is gradually increased until the phenomenon that plating leakage occurs or the bonding force is lower than a specified value is caused_maxThen the operating range of d is d_min<d<d_max。

The processing parameters, d, of FIG. 4a₁Is slightly larger than d_minThe binding force hundred lattice test can reach 5B; processing parameters of FIG. 4b, d₁<d₂<d_maxThe binding force is reduced to 4B; processing parameters of FIG. 4c, d₃>d_maxAs a result, plating leakage occurs.

And testing the corresponding relation between the laser processing parameters under different beam expansion multiples (beam waist diameters) under the fixed power density and the actually measured width of the plated conductive pattern.

In the prior art, the material processing track of the laser is determined based on the beam waist diameter inherent to the system. In fact, the effect of the same beam is different from that of different materials under different environments, the actual size of the pattern formed on the material by the beam is often different from the known beam waist diameter, and the intrinsic beam waist diameter is not exactly equal to the actual width after the beam is reacted with the material, so that a certain deviation is generated. The processing track is determined based on the inherent beam waist diameter, and the application range of the method to the processing precision, the line width and the like is limited.

After laser processing, at least one chemical plating is needed, and after chemical plating, a majority of products also need to be electroplated with a conductive metal layer and a protective metal layer. After the chemical plating and electroplating processes, the dimension changes to a small extent due to the diffusion effect in a certain range, which is more likely to cause the problem of the dimension precision of the pattern.

The method of the invention comprises an on-line zooming beam expanding system. According to the conditions of laser energy density, laser power density and the like determined in the step (2), firstly fixing a beam expansion multiple, changing the power, keeping the energy and the power on a unit area unchanged, and actually measuring the width of the plated metal wire. And then, under the condition that the power density is not changed, continuously changing the beam expanding multiple, and actually measuring the width of the plated metal wire. And finally, obtaining the corresponding relation between the beam waist diameter of the light beam under different beam expansion multiples and the actual size of the circuit pattern, and setting a certain size compensation value according to the result.

(3) The substrate is laser machined.

And processing according to the set processing path and laser parameters, wherein the laser processing at the step has two functions. One is to selectively destroy the adjusted surface state to form a difference between the deposition of the activator at the processed portion and the deposition of the activator at the unprocessed portion; the other is to form a certain array of pits, the pits have certain conserving effect on liquid (activating agent), the unprocessed part has no pits and can not retain the liquid, the pits also have different effects on the deposition of the activating agent on the processed part and the unprocessed part, and simultaneously, the pits can improve the bonding force between the metallized metal layer and the substrate.

These two effects are in the same direction for activator deposition, with both the laser-machined sites favoring activator deposition and the unprocessed sites favoring activator deposition. The two effects are superposed in the positive direction, so that the selectivity is enhanced, and the control on the overflow plating and the skip plating is better.

The beam expansion multiple of the equipment used by the invention can be changed on line, and when encountering pixels with narrow width, the equipment becomes a thin beam for processing; when a pixel with a large width is encountered, the processing becomes rough beam processing. Wherein, the laser energy density and the laser power density determined in the step (2) are constant, the corresponding relation between the established pattern size and the required beam waist diameter is the basis of the beam waist diameter change, and the laser processing parameters are generated by software, and the laser processing parameters comprise: energy density values, power density values, beam waist diameters, repetition rates, overlap rates, processing paths, and the like. When the beam waist diameter of the light beam is determined, the processing speed is used as a priority condition, any two processed pits cannot be overlapped to be used as a constraint condition, and the laser energy projected on a unit area and the laser power on the unit area are kept unchanged.

(4) And (3) putting the substrate into an activating solution for activation.

The process of activation is essentially "seeding". The essence of the activation process is to deposit catalytically active metal in the form of colloidal particles or sparingly soluble compounds on the surface of the material, and when entering the electroless plating solution, these particles become catalytic centers, reducing the metal to deposit on the plastic surface to form an electroless plating.

There are two types of activation solutions commonly used, one being an ionic activation solution and the other being a colloidal activation solution. The sizes of the activated particles in the two activating liquids are all nano-scale, and the pits made by the laser single pulse are far larger than the particles, so the activating liquids have a function of conserving the particles. However, some materials have weak adsorption effect on the activated particles and low conservation quantity, and at the moment, means such as ultrasonic waves and the like can be added to improve the conservation quantity of the interior of the pits on the activated particles, so that the selectivity can be further improved.

(5) And placing the substrate in an electroless plating solution to deposit a metal layer.

Electroless plating is a process of forming a metal layer by reducing metal atoms from metal ions in a plating solution on the surface of a substrate having catalytic activity with a reducing agent. For insulating materials, a metal layer can be deposited in an electroless plating solution only by first depositing catalytic center particles on the surface of the insulating material.

After the steps (1) to (4), catalytic particles are arranged on the laser processed part on the surface of the material, and catalytic particles are not arranged on the unprocessed part; after the chemical plating solution is fed, metal deposition exists on the laser-processed part, no metal deposition exists on the unprocessed part, and selective metallization is realized after the chemical plating is finished to form a metallization circuit of an electronic pattern.

The equipment used by the invention 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 turning system, a workpiece and light beam movement and control system, an automatic and manual workpiece feeding and discharging 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, and is characterized in that: the laser beam waist diameter changing device can match different beam waist diameters by taking energy and power on a unit area as constant quantities according to a circuit graph 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 to process under the condition that the energy and the power on the unit area are constant at set values.

The beam waist diameter of the laser beam in the invention changes with the pattern size, but the energy density and the power density are not changed, the relation between the laser parameter and the processing result is obtained according to the measured value of the coating layer, and the relation is applied to the processing process through a data processing system and an equipment control system, thereby exerting the advantages of chemical treatment, eliminating the problem of chemical treatment and realizing selectivity by using laser. The processing consistency is good, the quality is reliable, the speed is high, the parameters and indexes are specific, and the process is controllable.

The invention has the advantages and beneficial effects that:

the method provided by the invention firstly provides that the surface of the base material is subjected to regulation which is not beneficial to palladium deposition, and then laser processing is carried out, so that the contrast between a processed part and an unprocessed part is more beneficial to the selectivity of an activating agent. Compared with other non-treatment process technologies, the method has the advantages of less overflow plating and higher qualification rate.

The existing partial 3D-MID technology has the principle that selective processing of laser is utilized, the surface of a substrate is firstly melted by high power, then a honeycomb layer with a certain thickness and a micro-porous structure is formed along with partial gasification, and selective deposition of an activating agent is facilitated. However, for thermosetting insulating materials, such techniques are not suitable for thermosetting insulating materials because the material itself has no reflow characteristics. Particularly, during the advanced laser technology processing such as ultraviolet picosecond and femtosecond, the direct sublimation is realized, the part without melting is not formed, and a loose hole structure with certain thickness cannot be formed. The minimum line-to-line spacing for such technologies is substantially 100-150 um.

The method provided by the invention defines the rough surface state after laser processing, provides a pit theory, can be processed by using new laser technologies such as ultraviolet picosecond and femtosecond, and can be applied to thermoplastic and thermosetting materials (such as figures 5a, 5b and 5 c). And the novel laser technologies such as ultraviolet picosecond and femtosecond are used for processing, the processed graph is finer, and the minimum line width space can be close to the size of a laser spot and is far lower than 100 um.

In the existing technology for forming the porous structure after processing, the uppermost layer of the porous layer is a looser carbonized structure, the structure has great influence on the binding force between the metal layer and the base material, and methods such as chemical roughening and the like must be added to improve the binding force. According to the method provided by the invention, the pits on the surface of the processed material can provide bonding force with a value more than a specified value (such as fig. 6a and 6 b). The laser processing can be observed under a microscope of 1000 times of 100-. Therefore, the binding force is increased without chemical coarsening, the influence on the environment is small, and the method is more environment-friendly.

Drawings

FIG. 1 is a schematic flow diagram of an embodiment of the present invention for selectively activating and metallizing an insulating material using a laser;

FIG. 2a is a schematic representation (500 times magnification) of the results after normal implementation of the method according to the invention;

FIG. 2b is a schematic representation (100 times magnification) of the results after normal implementation of the method according to the invention;

FIG. 3a is a drawing of the effect of the surface conditioning plating;

FIG. 3b is a graph showing the effect of plating without surface modification under the same laser parameters and metallization solution parameters as in FIG. 3 a;

fig. 4a is an exemplary diagram of pit spacing 20 x 20 um;

fig. 4b is an exemplary diagram of pit spacing 30 x 30 um;

fig. 4c is an exemplary diagram of pit spacing 50 × 50 um;

FIG. 5a is a photograph of an ABS substrate after metallization;

FIG. 5b is a photograph of a PC substrate after metallization;

FIG. 5c is a photograph of a FR4 substrate after metallization;

FIG. 6a shows the result of ABS material adhesion test (Baige experiment);

FIG. 6b shows the results of PC material binding force test (Baige experiment);

FIG. 7 is a schematic representation of the presence of colloidal palladium in solution;

FIG. 8 is the overall appearance of the sample of example 2;

FIG. 9 is a picture of a sample taken at 100 times magnification;

fig. 10 is a picture of a sample magnified 1000 times.

Detailed Description

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

The first embodiment is as follows:

the material of this example is a conventional grade ABS plastic sheet, which is a polymer of three monomers, Acrylonitrile (acrylonitile), 1, 3-Butadiene (Butadiene), and Styrene (Styrene).

(1) The ABS substrate was surface conditioned.

The surface conditioning treatment process is preferably plasma treatment, and the gas proportion is preferably as follows: and (3) carrying out treatment for 1-3 minutes at the temperature of 30-70 ℃ under the condition of nitrogen/oxygen/carbon tetrafluoride being 1/8/2. The treated ABS substrate had increased hydrophilicity but had reduced adsorption of colloidal palladium.

(2) And setting a processing path and laser parameters.

The laser machining test is preferably performed in this example using a DirectLaser 600P ultraviolet picosecond laser machine manufactured by deum technology development ltd. The power is preferably 40-90%, and the pit diameters after processing of single pulse or pulse train with various power percentages are shown in the following table:

percentage of power/%)	40	50	60	70	80	90
							Pit diameter dmin/um	11.6	13.5	14.7	15.2	17.4	19

The preferred power percentage is 50%. The processing pattern is generated using a data processing software circuit cam 7 of dezhong (tianjin) technology development ltd, and the processing line pitch of the pattern is preferably set to 15 um.

Operational parameters were set on the laser machine using dreamcretor 3, a device driver from dezhong (tianjin) technical development limited. The power percentage is 50%, the frequency is 50-200kHz, and the scanning speed is as follows: frequency number 15um (in mm/s depending on the laser spot size used, the scanning speed limit of the galvanometer).

(3) The substrate is laser machined.

Processing according to the parameters tested in the step (2), wherein the power is preferably 50%, the frequency is 50-200kHz, and the scanning speed is as follows: frequency number 15 um.

(4) Putting the base material into an activating solution for activation;

the activation process of the embodiment is preferably an activation process of degreasing-presoaking-colloid palladium-dispergation. Wherein:

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.

The preferable presoaking solution comprises: hydrochloric acid 200ml/L, room temperature, time 1-3 min.

③ the preferred solution composition of colloidal palladium is: 0.05g/L of palladium chloride, 10g/L of matte tin chloride, 200ml/L of hydrochloric acid and 50g/L of sodium chloride, the temperature is 25-35 ℃, and the time is 1-5 min.

The preferable solution for disperging comprises: ethyl UDIQUE 8812ACCELERATOR 250ml/L, temperature 40-55 deg.C, time 2-10 min.

In this embodiment, an alkaline electroless copper plating solution is preferably used, the solution composition being: 13-17g/L of copper chloride, 30-40g/L of ethylene diamine tetraacetic acid, 10-15g/L of sodium hydroxide, 10-14ml/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 10-150min of time.

(6) And (4) testing results:

placing the sample under a magnifying glass, observing under the condition of 100 times, wherein the edge of the metal pattern is clear, and no excessive plating exists, as shown in figure 2 b; observed under 500 times, the line width spacing can reach 35-50um, as shown in fig. 2 a.

The hundreds lattice test reaches 5B as in fig. 6 a.

Example 2

The material of this example used a PC (40%) + ABS plastic alloy.

(1) Coating the surface of PC (40%) + ABS material with a coating.

The kind of the coating is preferably organic silicon resin, and the solid content of the prepared solution is 2-6%. Coating in a dipping mode for 3-10s at normal temperature.

Surface tension was tested using dynes. The material surface tension before coating was 36 and after coating dropped to 32. And observing and comparing under a microscope, wherein the surface of the substrate has micro pits which can not be seen by naked eyes before coating, and the micro pits are filled after coating.

(2) And setting a processing path and laser parameters.

In the present embodiment, a DirectLaser U5 uv nanosecond laser machine manufactured by tianjin technical development ltd is preferably used for laser processing. The apparatus has a variable magnification beam expanding system.

The initial beam expansion factor is 3 times, the diameter of the beam waist is 15um, under the condition that other parameters are not changed, in order to simplify the process, only the output power of the laser is adjusted to change the laser processing energy density, the power is preferably 9.6-21.6w, single line scanning is carried out, and in order to prevent pits with unknown sizes from overlapping, the scanning speed is initially set to be 2500mm/s (50kHz 50 um).

The coating was removed and an array of pits was formed and the size of the pit diameter was measured under a microscope. The diameter of the pits for several power processes are shown in the following table:

average power/W	9.6	12	14.4	16.8	19.2	21.6
							Pit diameter dmin/um	11.3	13.1	14.8	15.5	17.9	19.2

In the case of a fixed frequency of 50kHz, an average work of 12w is preferred, corresponding to an average power density of 6791kW/cm²。

(3) And testing the corresponding relation between the laser processing parameters under different beam expansion multiples (beam waist diameters) under the fixed power density and the actually measured width of the plated conductive pattern.

In this embodiment, the beam waist diameter d corresponding to the variable beam expander_rThe range of (7.5-45.2um) is set to 5 kinds of d_rAnd (3) carrying out a separate experiment, calculating the optical power P with a corresponding proportion by taking the average power density finally obtained in the step (2) as a constant, and measuring 5 corresponding minimum widths d of the plating layers after metallization. Measured d_rData d, P are as follows:

beam waist diameter dr/um:	7.5	9	15	22.6	45.2
						multiple of beam expansion	6	5	3	2	1
Laser power P/w	3	4.32	12	27.2	108.96
						Minimum line width d/um after plating	13.5	15	24	30	53

(4) The substrate is laser machined.

According to the graph size of the processing pattern, using data processing software Circuit CAM 7 of Dezhong (Tianjin) technology development corporation to simulate laser processing, obtaining the needed beam expansion multiple, classifying, and generating a processing path file according to the classification.

Several laser machining parameters (tools) were generated on a laser machine using dreamcretor 3, a device driver from dezhong (tianjin) technology development limited, to set the operating parameters.

(5) Putting the base material into an activating solution for activation;

the activation process of the embodiment is preferably an activation process of presoaking, colloid palladium, dispergation and membrane removal. Wherein:

Sixthly, the preferable solution of the colloidal palladium comprises the following components: 0.05g/L of palladium chloride, 10g/L of matte tin chloride, 200ml/L of hydrochloric acid and 50g/L of sodium chloride, the temperature is 25-35 ℃, and the time is 1-5 min.

The preferable solution for debonding comprises: ethyl UDIQUE 8812ACCELERATOR 250ml/L, temperature 40-55 deg.C, time 1-2 min.

The preferable solution of the film removing liquid comprises: 10g/L of sodium hydroxide, normal temperature and 30-70s of time.

(6) And placing the substrate in an electroless plating solution to deposit a metal layer.

(7) And (4) testing results:

the overall appearance of the sample is shown in FIG. 8.

The sample is placed under a magnifying glass, and the metal pattern is observed under the condition of 100 times, the edge of the metal pattern is clear, and no overflow plating exists, as shown in figure 9. Observed under 1000 times, the line width can reach 15um, as shown in fig. 10.

Claims

1. A method of manufacturing a conductive pattern using a laser to selectively activate an insulating material, characterized by: the method comprises the following steps:

(1) carrying out surface adjustment on the insulating material;

(2) setting a specific processing path and laser parameters;

(3) carrying out laser processing on the base material;

(4) putting the base material into an activating solution for activation;

2. The method of claim 1, wherein: the surface conditioning is to make the material surface unfavorable for activator deposition.

3. The method of claim 2, wherein: the surface adjustment is to coat or impregnate a high polymer coating with the property of thinning the chemical plating active seeds on the surface of the material.

4. The method of claim 1, wherein: the laser parameters are set so that the laser processing can form a certain array of tiny pits on the surface of the base material, any two pits cannot be overlapped, and if the surface of the material is coated, the coating can be removed at the same time.

5. The method of claim 1, wherein: step (2) firstly, the size of a pit of a certain material after a single pulse or pulse train of laser is reacted with the material is confirmed, a certain processing path and laser parameters are set according to the laser processing characteristics of the material during processing, so that micro pits in a certain arrangement are formed on the surface of a base material after laser processing, and any two pits cannot be overlapped.

6. The method of claim 1, wherein: and (3) before laser processing, changing the beam expansion multiple, changing the laser power in proportion, keeping the energy and power on a unit area unchanged, actually measuring the width of the plated metal wire, and finally obtaining the corresponding relation between the beam waist diameters of the light beams with different beam expansion multiples and the size of the circuit pattern under a certain power density.

7. The method of claim 1, wherein: and (4) accumulating and selectively removing the activating solution dredging coating to cause that the processed part and the unprocessed part have two effects of distinguishing the deposition of the activating agent and the retaining effect of the pit on the activating solution, so that the activating process is selective.

8. The method of claim 1, wherein: and (5) depositing metal on the laser-processed positions on the surface of the base material, not depositing metal on the non-processed positions, and forming a metal circuit of an electronic pattern on the surface of the base material after the deposition is finished.