Circuit board pretreatment process for automobile front-view camera and circuit board

Abstract

The invention provides a circuit board pretreatment process for an automobile front-view camera and a circuit board. The circuit board pretreatment process for the automobile front-view camera comprises the following steps: cutting a copper-clad plate to form a substrate; the substrate is subjected to needle brush plate grinding operation, so that the surface of the substrate is rough, and the grinding current ranges from 0.6 A to 1.0 A; performing micro-etching operation on the substrate so as to increase the surface roughness of the substrate; carrying out cleaning operation on the substrate; carrying out pattern imaging operation on the substrate so as to form a circuit layer on the substrate; and AOI optical detection is conducted on the substrate, and the illumination intensity ranges from 110 Lx to 130 Lx. A needle brush is adopted in the board grinding process, the current of the grinding brush is 0.6-1.0 A, etching is carried out after board grinding, the copper surface of the substrate is rough, and then copper surface reflection of the substrate in the AOI optical detection process is slowed down.

Description

Technical Field

[0001] The present disclosure relates to the field of circuit boards, and in particular to a circuit board pre-processing process and a circuit board for a front-view camera of an automobile. Background Art

[0002] The circuit board used for the front-view camera of the car has many functional modules, so the circuits are densely packed. Correspondingly, the dimensional accuracy of the circuit board is required to be high. At the same time, the AOI inspection process after the circuit board is formed needs to be accurate and error-free to ensure that there are no problems with the circuit board. The traditional AOI inspection and recognition images are black and white pictures with low accuracy, which is difficult to meet the increasingly high requirements. The recognition of the AOI color optical inspection machine is currently affected by factors such as the AOI light source and the reflected light from the copper surface of the circuit board. During the production process, the parameters of the inspection machine need to be repeatedly debugged, which seriously affects the production efficiency.

[0003] Therefore, there is an urgent need for a circuit board pre-processing process that can slow down the reflection of the copper surface of the circuit board and increase the detection efficiency. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a circuit board pre-processing process and a circuit board for a front-view camera of an automobile that can slow down the reflection of the copper surface of the circuit board and improve the detection efficiency.

[0005] The purpose of this disclosure is achieved through the following technical solutions:

[0006] A circuit board pre-processing process for a front-view camera of an automobile comprises the following steps:

[0007] Cutting the copper clad laminate to form a substrate;

[0008] Performing a needle brush grinding operation on the substrate to roughen the surface of the substrate, wherein the grinding brush current is 0.6A-1.0A;

[0009] Performing micro-etching on the substrate to increase the surface roughness of the substrate;

[0010] performing a cleaning operation on the substrate;

[0011] Performing a graphic imaging operation on the substrate to form a circuit layer on the substrate;

[0012] The substrate is subjected to AOI optical inspection, wherein the light intensity is 110 Lx-130 Lx.

[0013] In one embodiment, the needle brush grinding operation is performed on the substrate, which specifically includes the following steps:

[0014] placing the substrate into a brushing machine so that the substrate is located between two needle brushes;

[0015] The brushing machine is started, the substrate moves in a straight line, and the two needle brushes rotate relative to the substrate, and the rotation direction of the two needle brushes is opposite to the forward direction of the substrate.

[0016] In one embodiment, the substrate is subjected to a needle brush grinding operation to make the surface of the substrate rough, which specifically includes the following steps:

[0017] The substrate is initially ground, the needle brush current is 0.6A-0.8A, and the needle brush rotation speed is 1600r / min-1800r / min.

[0018] In one embodiment, after the micro-etching operation is performed on the substrate and before the cleaning operation is performed on the substrate, the following steps are further included:

[0019] The substrate is subjected to secondary grinding, the needle brush current is 0.9A-1.0A, and the needle brush rotation speed is 1200r / min-1300r / min.

[0020] In one embodiment, the conveying direction of the substrate during the primary grinding is opposite to the conveying direction of the substrate during the secondary grinding; and,

[0021] The direction of rotation of the needle brush during the initial grinding of the plate is opposite to the direction of rotation of the needle brush during the secondary grinding of the plate.

[0022] In one embodiment, the cleaning operation of the substrate specifically includes the following steps:

[0023] performing a first water washing operation on the substrate;

[0024] Performing a pickling operation on the substrate;

[0025] The substrate is subjected to a second water washing operation.

[0026] In one embodiment, micro-etching the substrate specifically comprises the following steps:

[0027] The substrate is sprayed with an alkaline etching solution to increase the roughness of the substrate surface.

[0028] In one embodiment, performing a graphic imaging operation on the substrate specifically comprises the following steps:

[0029] Performing a lamination operation on the substrate;

[0030] performing an exposure operation on the substrate;

[0031] Performing a developing operation on the substrate;

[0032] performing an etching operation on the substrate;

[0033] The substrate is subjected to a film stripping operation to form a circuit layer on the substrate.

[0034] In one embodiment, after the substrate is cleaned and before the substrate is imaged, the following steps are further included:

[0035] A baking operation is performed on the substrate.

[0036] A circuit board is prepared by using the circuit board pre-treatment process for a front-view camera of an automobile as described in any of the above embodiments.

[0037] Compared with the prior art, the present invention has at least the following advantages:

[0038] In the above-mentioned circuit board pre-treatment process for automotive front-view cameras, the copper-clad laminate is cut to form a substrate, the substrate is subjected to needle brush grinding, and the grinding current is 0.6A-1.0A, so that the surface of the substrate after grinding is rough, and then the substrate is etched to increase the roughness of the substrate surface, that is, the surface of the substrate is no longer smooth and flat, so that the substrate has a stronger bonding force with ink, photosensitive film, etc., and at the same time, the reflection of the copper surface of the substrate is slowed down, and then the substrate is cleaned and a graphic imaging operation is performed to form a circuit layer on the surface of the substrate, and finally the substrate is subjected to AOI optical inspection, and the light intensity of the AOI optical equipment is 110Lx-130 Lx. Under this light intensity, the AOI optical equipment can clearly image and inspect the copper surface of the substrate. Specifically, by using a needle brush in the grinding process, the brush current is 0.6A-1.0A, and etching is performed after grinding, the copper surface of the substrate is roughened, thereby slowing down the copper surface reflection of the substrate in the AOI optical inspection process, so that the substrate can be clearly imaged and inspected under a light intensity of 110Lx-130 Lx, thereby reducing repeated debugging of equipment parameters and improving inspection efficiency and production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present disclosure and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0040] Figure 1 The present invention is a process flow chart of a circuit board pre-processing process for a front-view camera of an automobile according to an embodiment;

[0041] Figure 2 for Figure 1 The schematic diagram of substrate conveying for the circuit board pre-processing process of the automotive front-view camera is shown;

[0042] Figure 3 To adopt Figure 1 The image obtained after the pre-processing process of the circuit board used for the front-view camera of the car is shown;

[0043] Figure 4 This is an image obtained after a non-woven fabric is used to brush and polish a plate in one embodiment;

[0044] Figure 5 This is an image obtained after a ceramic grinding brush is used to grind the plate in one embodiment;

[0045] Figure 6 It is the copper surface of the substrate that has not been pre-treated;

[0046] Figure 7 To adopt Figure 1 The copper surface of the substrate after the pre-processing process of the circuit board used for the automotive front-view camera is shown. DETAILED DESCRIPTION

[0047] In order to facilitate the understanding of the present disclosure, the present disclosure will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present disclosure are given in the drawings. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present disclosure more thoroughly and comprehensively understood.

[0048] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0049] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present disclosure. The terms used herein in the specification of the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0050] The present disclosure provides a circuit board pre-processing process for a front-view camera of an automobile, comprising the following steps: performing a cutting operation on a copper-clad laminate to form a substrate; performing a needle brush grinding operation on the substrate to make the surface of the substrate rough, wherein the grinding brush current is 0.6A-1.0A; performing a micro-etching operation on the substrate to increase the surface roughness of the substrate; performing a cleaning operation on the substrate; performing a graphic imaging operation on the substrate to form a circuit layer on the substrate; and performing an AOI optical inspection on the substrate, wherein the illumination intensity is 110Lx-130Lx.

[0051] In the above-mentioned circuit board pre-treatment process for automotive front-view cameras, the copper-clad laminate is cut to form a substrate, the substrate is subjected to needle brush grinding, and the grinding current is 0.6A-1.0A, so that the surface of the substrate after grinding is rough, and then the substrate is etched to increase the roughness of the substrate surface, that is, the surface of the substrate is no longer smooth and flat, so that the substrate has a stronger bonding force with ink, photosensitive film, etc., and at the same time, the reflection of the copper surface of the substrate is slowed down, and then the substrate is cleaned and a graphic imaging operation is performed to form a circuit layer on the surface of the substrate, and finally the substrate is subjected to AOI optical inspection, and the light intensity of the AOI optical equipment is 110Lx-130 Lx. Under this light intensity, the AOI optical equipment can clearly image and inspect the copper surface of the substrate. Specifically, by using a needle brush in the grinding process, the brush current is 0.6A-1.0A, and etching is performed after grinding, the copper surface of the substrate is roughened, thereby slowing down the copper surface reflection of the substrate in the AOI optical inspection process, so that the substrate can be clearly imaged and inspected under a light intensity of 110Lx-130 Lx, thereby reducing repeated debugging of equipment parameters and improving inspection efficiency and production efficiency.

[0052] In order to better understand the technical solutions and beneficial effects of the present invention, the present invention is further described in detail below in conjunction with specific embodiments:

[0053] like Figure 1 As shown, a circuit board pre-processing process for a front-view camera of an automobile in one embodiment includes the following steps:

[0054] S100: Cutting the copper clad laminate to form a substrate.

[0055] In this embodiment, a large-area copper-clad laminate is cut into a designed size to form a substrate of the required size. After cutting, the substrate needs to be rounded on all sides so that the four sides of the substrate are no longer sharp, thereby avoiding scratches caused by collision of the board surface during subsequent processes.

[0056] S200: performing a needle brush grinding operation on the substrate to roughen the surface of the substrate, wherein the grinding brush current is 0.6A-1.0A.

[0057] It is understandable that the surface of the substrate after cutting is flat and smooth, which is not conducive to combining with ink and photosensitive film. At this time, the surface of the substrate needs to be ground to make the surface of the substrate rough so as to better combine with ink and photosensitive film. In this embodiment, a needle brush is used to grind the surface of the substrate, and the grinding current is controlled at 0.6A-1.0A, that is, the needle brush rotates under the action of a current of 0.6A-1.0A, so that the needle brush presses the surface of the substrate, thereby forming small pits on the surface of the substrate, that is, making the surface of the substrate rough, thereby making the bonding between the substrate and the ink and photosensitive film better. Furthermore, while making the surface of the substrate rough, the surface of the substrate is no longer smooth, so that the reflection effect of the substrate on light is weakened, thereby making the imaging of the substrate in the AOI detection process clearer.

[0058] S300: performing micro-etching on the substrate to increase the surface roughness of the substrate.

[0059] In this embodiment, in order to further increase the roughness of the substrate surface, chemical reagents are used to etch the substrate. Under the action of the chemical reagents, the copper surface of the substrate is corroded, that is, the pits formed on the copper surface of the substrate are larger in area and more in number, thereby making the surface of the substrate rougher, further slowing down the reflection effect of the substrate on light, making the substrate image clearer in the AOI inspection process.

[0060] S400: performing a cleaning operation on the substrate.

[0061] It is understandable that copper powder will remain on the surface of the substrate after the needle brush grinding operation, and chemical reagents will remain on the surface of the substrate after the micro-etching operation. If the copper powder and chemical reagents on the substrate are not removed in time, the effect of the subsequent process will be affected. In this embodiment, the surface of the substrate is sprayed with a high-pressure water gun. Under the action of the high-pressure water flow pressure, the copper powder and chemical reagents in the pits on the surface of the substrate can be completely removed, so that the substrate can be better processed for the next process.

[0062] S500: performing a pattern imaging operation on the substrate to form a circuit layer on the substrate.

[0063] It is understandable that a circuit layer needs to be formed on the surface of the substrate so that the substrate is connected to the electronic device. In this embodiment, a photosensitive film is attached to the surface of the substrate, and the pattern circuit on the photosensitive film is transferred to the surface of the substrate by ultraviolet light irradiation, and then the substrate is etched and the film is stripped, so that the required circuit pattern is formed on the surface of the substrate.

[0064] S600: Performing AOI optical inspection on the substrate, wherein the light intensity is 110 Lx-130 Lx.

[0065] It is understandable that the substrate needs to be inspected after the circuit is formed to ensure that the formed circuit meets the requirements, especially for the circuit board used for the front-view camera of the car, which has more functional modules and the circuits formed on the substrate are dense, so the accuracy of the inspection is required to be high. In this embodiment, optical inspection is performed by AOI optical equipment, and the AOI optical equipment images a color picture. The light source used by the AOI optical equipment is LED light. The substrate is inspected under the parameter of light intensity of 110Lx-130 Lx. Since the substrate is subjected to needle brush grinding and micro-etching operations, the surface of the substrate is relatively rough, which makes the reflection effect of the substrate surface on light weak. Under the parameter of light intensity of 110Lx-130 Lx, the equipment can clearly image and detect, thus avoiding the need to repeatedly debug the parameters of the equipment and improving the accuracy of the inspection.

[0066] In the above-mentioned circuit board pre-treatment process for automotive front-view cameras, the copper-clad laminate is cut to form a substrate, the substrate is subjected to needle brush grinding, and the grinding current is 0.6A-1.0A, so that the surface of the substrate after grinding is rough, and then the substrate is etched to increase the roughness of the substrate surface, that is, the surface of the substrate is no longer smooth and flat, so that the substrate has a stronger bonding force with ink, photosensitive film, etc., and at the same time, the reflection of the copper surface of the substrate is slowed down, and then the substrate is cleaned and a graphic imaging operation is performed to form a circuit layer on the surface of the substrate, and finally the substrate is subjected to AOI optical inspection, and the light intensity of the AOI optical equipment is 110Lx-130 Lx. Under this light intensity, the AOI optical equipment can clearly image and inspect the copper surface of the substrate. Specifically, by using a needle brush in the grinding process, the brush current is 0.6A-1.0A, and etching is performed after grinding, the copper surface of the substrate is roughened, thereby slowing down the copper surface reflection of the substrate in the AOI optical inspection process, so that the substrate can be clearly imaged and inspected under a light intensity of 110Lx-130 Lx, thereby reducing repeated debugging of equipment parameters and improving inspection efficiency and production efficiency.

[0067] In one embodiment, the needle brush grinding operation is performed on the substrate, which specifically includes the following steps:

[0068] placing the substrate into a brushing machine so that the substrate is located between two needle brushes;

[0069] The brushing machine is started, the substrate moves in a straight line, and the two needle brushes rotate relative to the substrate, and the rotation direction of the two needle brushes is opposite to the forward direction of the substrate.

[0070] In this embodiment, after the substrate enters the grinding machine, it is transported by the conveying device to between the two needle brushes, so that the two needle brushes grind the two sides of the substrate respectively. Furthermore, the substrate moves in a straight line, and the two needle brushes rotate relative to the substrate. The two needle brushes rotate in the same direction, and the rotation direction of the two needle brushes is opposite to the forward direction of the substrate. Specifically, Figure 2 As shown, when the substrate moves from X to Y, the two needle brushes rotate clockwise, and when the substrate moves from Y to X, the two needle brushes rotate counterclockwise, so that the friction between the substrate and the two needle brushes is greater, so as to better grind the substrate. Furthermore, the two needle brushes move back and forth in the horizontal direction under the drive of the driver, so that the contact between the two needle brushes and the substrate is more uniform, thereby making the surface roughness of the substrate more uniform.

[0071] In one embodiment, the number of the needle brushes is at least two, so that the substrate is located between the two needle brushes, so that the two substrates can grind the two sides of the substrate at the same time. Further, in other embodiments, the number of the needle brushes can be multiple, and the needle brushes are paired in pairs, so that a pair of needle brushes can grind the two sides of the substrate at the same time, so as to achieve a better grinding effect on the substrate.

[0072] In one embodiment, the substrate is subjected to a needle brush grinding operation to make the surface of the substrate rough, which specifically includes the following steps:

[0073] The substrate is initially ground, the needle brush current is 0.6A-0.8A, and the needle brush rotation speed is 1600r / min-1800r / min.

[0074] It can be understood that when the substrate is ground for the first time, the needle brush current is 0.6A-0.8A, that is, the pressure of the needle brush on the substrate is relatively small, and the rotation speed of the needle brush is 1600r / min-1800r / min, that is, the rotation speed of the needle brush is relatively high. This is because before the substrate is ground, there are some fiber particles or oxide films and other substances on the surface of the substrate. These impurities will cause short circuit or open circuit of the circuit board during production. By grinding the substrate for the first time and controlling the needle brush current at 0.6A-0.8A, the pressure of the needle brush on the substrate is small, and impurities will not be pressed into the surface of the substrate. At the same time, the rotation speed of the needle brush is controlled at 1600r / min-1800r / min, so that the needle brush rotates quickly, thereby scraping impurities from the surface of the substrate.

[0075] In one embodiment, after the micro-etching operation is performed on the substrate and before the cleaning operation is performed on the substrate, the following steps are further included:

[0076] The substrate is subjected to secondary grinding, the needle brush current is 0.9A-1.0A, and the needle brush rotation speed is 1200r / min-1300r / min.

[0077] It can be understood that when the substrate is ground for the second time, the needle brush current is 0.9A-1.0A, that is, the pressure of the needle brush on the grinding plate is greater than that during the first grinding, and the brush speed is 1200r / min-1300r / min, that is, the speed of the needle brush is slower than that during the first grinding. At this time, since the impurities on the substrate have been removed by the first grinding, the needle brush exerts greater pressure on the substrate and rotates slower during the second grinding, which makes the needle brush exert greater force on the surface of the substrate and acts for a longer time, thereby making the depth of the pits formed on the surface of the substrate greater, and making the surface of the substrate rougher.

[0078] It should be noted that after the initial grinding and micro-etching operations, the surface of the substrate is relatively rough, that is, the copper layer on the surface of the substrate has been worn a lot, but has not yet reached the preset surface roughness. At this time, it is necessary to accurately control the current and speed of the secondary grinding. This is because the copper layer on the surface of the substrate is worn a lot. If the current of the secondary grinding is large, that is, the pressure of the needle brush on the substrate is large, it is easy to wear the copper layer, and then cause the resin layer of the copper layer to be damaged. At the same time, it is easy for the residual etching solution to penetrate into the resin layer, causing corrosion of the resin layer, reducing the service life of the substrate. In order to solve the above problems, in one embodiment, the secondary grinding of the substrate specifically includes the following steps:

[0079] collecting a first roughness of the surface of the substrate;

[0080] Detecting whether a first roughness of the substrate surface matches a preset surface roughness;

[0081] When the first roughness of the substrate surface is greater than or equal to the preset surface roughness, the brushing current of the needle brush is reduced and the rotation speed of the needle brush is increased.

[0082] It can be understood that the first roughness of the substrate surface is the surface roughness after one grinding and micro-etching operation. After the initial grinding and micro-etching operation, the surface of the substrate is relatively rough. At this time, it is necessary to accurately control the current and rotation speed of the secondary grinding. This is because the copper layer on the surface of the substrate is more worn. If the current of the secondary grinding is large, that is, the pressure of the needle brush on the substrate is large, the copper layer is easily worn, and then the resin layer under the copper layer is damaged. At the same time, the residual etching solution is easy to penetrate into the resin layer, causing corrosion of the resin layer, reducing the service life of the substrate. Specifically, the first roughness of the substrate surface is collected by an optical device to detect whether the first roughness of the substrate surface is greater than or equal to a preset surface roughness. The preset surface roughness is a preset range value of the substrate surface roughness after a grinding and micro-etching operation. When the first roughness of the substrate surface is greater than or equal to the preset surface roughness, it indicates that the substrate surface is relatively rough at this time, that is, the copper layer of the substrate is more worn. At this time, the grinding current of the needle brush is reduced and the rotation speed of the needle brush is increased. The grinding current of the needle brush is reduced to reduce the force of the needle brush on the substrate surface, so that the needle brush wears less on the substrate surface. The rotation speed of the needle brush is increased to make the needle brush contact the substrate surface more times per unit time. That is, by increasing the number of contacts between the needle brush and the substrate and reducing the force of the needle brush on the substrate, the roughness of the secondary grinding of the substrate is controlled within a preset range, thereby achieving precise control of the secondary grinding of the substrate. At the same time, it also avoids the problem that the secondary grinding causes more wear on the copper layer on the substrate surface, resulting in damage to the resin layer.

[0083] In one embodiment, detecting whether the first roughness of the surface of the substrate matches a preset surface roughness includes:

[0084] When the first roughness of the substrate surface is less than the preset surface roughness, the brushing current of the needle brush is increased and the rotation speed of the needle brush is reduced. It can be understood that when the first roughness of the substrate surface is less than the preset surface roughness, it indicates that the surface roughness of the substrate at this time does not reach the expected roughness after the first grinding and micro-etching. At this time, by increasing the brushing current of the needle brush, the force of the needle brush on the substrate surface is increased, and the rotation speed of the needle brush is reduced at the same time. This is to make the needle brush stay on the substrate surface for a longer time per unit time, so that the needle brush and the substrate are in better contact, and then the pits formed by the needle brush on the substrate surface are deeper and more numerous, that is, the substrate surface is rougher, so as to achieve the expected effect of the secondary grinding and realize the precise control of the secondary grinding.

[0085] In one embodiment, the conveying direction of the substrate during the primary grinding is opposite to the conveying direction of the substrate during the secondary grinding; and,

[0086] The direction of rotation of the needle brush during the initial grinding of the plate is opposite to the direction of rotation of the needle brush during the secondary grinding of the plate.

[0087] In this embodiment, the conveying direction of the substrate during the first grinding is opposite to the conveying direction of the substrate during the second grinding. Specifically, Figure 2 As shown, when the substrate is first polished, the substrate moves from the X to the Y direction, and when the substrate is second polished, the substrate moves from the Y to the X direction, so that the contact position between the substrate and the needle brush is different during the first polishing and the second polishing, that is, the path of the needle brush is inconsistent during the two polishing processes, so that the path of the needle brush on the substrate is more complicated, the number of pits formed on the substrate is more and more dense, and then the surface of the substrate is rougher, and the imaging of the substrate in the AOI inspection process is clearer. Correspondingly, the rotation direction of the two needle brushes during the first polishing is opposite to that during the second polishing, so that the two needle brushes are adapted to the conveying direction of the substrate during the two polishing processes.

[0088] In one embodiment, the cleaning operation of the substrate specifically includes the following steps:

[0089] performing a first water washing operation on the substrate;

[0090] Performing a pickling operation on the substrate;

[0091] The substrate is subjected to a second water washing operation.

[0092] It is understandable that copper powder will remain on the surface of the substrate after the needle brush grinding operation, and chemical reagents will remain on the surface of the substrate after the micro-etching operation, which need to be removed before forming the circuit. In this embodiment, first, a high-pressure water gun is used to wash the surface of the substrate. Under the action of the high-pressure water flow pressure, the copper powder and chemical reagents on the surface of the substrate are removed; then, the substrate is pickled with an acidic test solution such as sulfuric acid and hydrochloric acid to remove the oxide layer on the surface of the substrate and prevent the surface of the substrate from oxidation; finally, the substrate is washed for the second time to remove the acidic test solution remaining on the surface of the substrate, completing the cleaning operation of the substrate.

[0093] In one embodiment, micro-etching the substrate specifically comprises the following steps:

[0094] The substrate is sprayed with an alkaline etching solution to increase the roughness of the substrate surface.

[0095] In this embodiment, an alkaline etching solution containing sodium hydroxide and hydrogen peroxide is used to etch the substrate, so that pits are etched on the surface of the substrate to increase the roughness of the substrate surface, further reduce the reflection effect of the substrate surface on light, and make the substrate image clearer in the AOI detection process. Furthermore, the alkaline etching solution is sprayed on the surface of the substrate through a spray device, so that the alkaline etching solution is in direct contact with the substrate surface, which increases the etching speed. At the same time, the etching solution stays on the substrate surface for a short time, reducing the phenomenon of side etching of the circuit board.

[0096] In one embodiment, performing a graphic imaging operation on the substrate specifically comprises the following steps:

[0097] Performing a lamination operation on the substrate;

[0098] performing an exposure operation on the substrate;

[0099] Performing a developing operation on the substrate;

[0100] performing an etching operation on the substrate;

[0101] The substrate is subjected to a film stripping operation to form a circuit layer on the substrate.

[0102] In this embodiment, first, a photosensitive dry film is attached to the surface of a substrate by a laminator, and then the circuit pattern on the film is transferred to the photosensitive dry film by an exposure machine. The photosensitive dry film is cured by ultraviolet irradiation, and the copper layer under the cured area of ​​the dry film is the desired circuit pattern; then, a developer is used to dissolve and rinse away the unexposed portion of the photosensitive dry film, leaving the photosensitive portion; then, an etching solution is used to dissolve and corrode the unexposed copper surface to obtain the desired circuit; finally, a stripper is used to remove the exposed photosensitive dry film to reveal the final desired circuit pattern.

[0103] In one embodiment, after the substrate is cleaned and before the substrate is imaged, the following steps are further included:

[0104] A baking operation is performed on the substrate.

[0105] It is understandable that the moisture on the substrate needs to be completely removed before graphic imaging to avoid residual moisture causing bubbles and stratification during the lamination process with the photosensitive dry film. The substrate is dried to a suitable temperature in an oven to ensure that there is no residual moisture on the substrate surface.

[0106] The present application also provides a circuit board, which is prepared using the circuit board pre-treatment process for a car front-view camera described in any of the above embodiments.

[0107] Compared with the prior art, the present invention has at least the following advantages:

[0108] In the above-mentioned circuit board pre-treatment process for automotive front-view cameras, the copper-clad laminate is cut to form a substrate, the substrate is subjected to needle brush grinding, and the grinding current is 0.6A-1.0A, so that the surface of the substrate after grinding is rough, and then the substrate is etched to increase the roughness of the substrate surface, that is, the surface of the substrate is no longer smooth and flat, so that the substrate has a stronger bonding force with ink, photosensitive film, etc., and at the same time, the reflection of the copper surface of the substrate is slowed down, and then the substrate is cleaned and a graphic imaging operation is performed to form a circuit layer on the surface of the substrate, and finally the substrate is subjected to AOI optical inspection, and the light intensity of the AOI optical equipment is 110Lx-130 Lx. Under this light intensity, the AOI optical equipment can clearly image and inspect the copper surface of the substrate. Specifically, by using a needle brush in the grinding process, the brush current is 0.6A-1.0A, and etching is performed after grinding, the copper surface of the substrate is roughened, thereby slowing down the copper surface reflection of the substrate in the AOI optical inspection process, so that the substrate can be clearly imaged and inspected under a light intensity of 110Lx-130 Lx, thereby reducing repeated debugging of equipment parameters and improving inspection efficiency and production efficiency.

[0109] Some specific examples are listed below, and if % is mentioned, it means percentage by weight. It should be noted that the following examples do not exhaust all possible situations, and the materials used in the following examples can be obtained from commercial sources unless otherwise specified.

[0110] Example 1

[0111] Cutting the copper clad laminate to form a substrate;

[0112] The substrate is subjected to a needle brush grinding operation, wherein the grinding brush current is 0.6A;

[0113] Performing micro-etching on the substrate to increase the surface roughness of the substrate;

[0114] performing a cleaning operation on the substrate;

[0115] Performing a graphic imaging operation on the substrate to form a circuit layer on the substrate;

[0116] Performing AOI optical inspection on the substrate, wherein the illumination intensity is 110Lx;

[0117] Turn off the light source of the AOI optical device, take out the substrate, and obtain the imaging data of the substrate.

[0118] Example 2

[0119] Cutting the copper clad laminate to form a substrate;

[0120] The substrate is subjected to a needle brush grinding operation, wherein the grinding brush current is 0.8A;

[0121] Performing micro-etching on the substrate to increase the surface roughness of the substrate;

[0122] performing a cleaning operation on the substrate;

[0123] Performing a graphic imaging operation on the substrate to form a circuit layer on the substrate;

[0124] Performing AOI optical inspection on the substrate, wherein the illumination intensity is 110Lx;

[0125] Turn off the light source of the AOI optical device, take out the substrate, and obtain the imaging data of the substrate.

[0126] Example 3

[0127] Cutting the copper clad laminate to form a substrate;

[0128] The substrate is subjected to a needle brush grinding operation, wherein the grinding brush current is 1.0A;

[0129] Performing micro-etching on the substrate to increase the surface roughness of the substrate;

[0130] performing a cleaning operation on the substrate;

[0131] Performing a graphic imaging operation on the substrate to form a circuit layer on the substrate; performing an AOI optical inspection on the substrate, wherein the illumination intensity is 110 Lx; turning off the light source of the AOI optical equipment, taking out the substrate, and obtaining imaging data of the substrate.

[0132] Example 4

[0133] Cutting the copper clad laminate to form a substrate;

[0134] The substrate is subjected to a needle brush grinding operation, wherein the grinding brush current is 0.6A;

[0135] Performing micro-etching on the substrate to increase the surface roughness of the substrate;

[0136] performing a cleaning operation on the substrate;

[0137] Performing a graphic imaging operation on the substrate to form a circuit layer on the substrate; performing an AOI optical inspection on the substrate, wherein the illumination intensity is 130Lx; turning off the light source of the AOI optical equipment, taking out the substrate, and obtaining imaging data of the substrate.

[0138] Example 5

[0139] Cutting the copper clad laminate to form a substrate;

[0140] The substrate is subjected to a needle brush grinding operation, wherein the grinding brush current is 0.8A;

[0141] Performing micro-etching on the substrate to increase the surface roughness of the substrate;

[0142] performing a cleaning operation on the substrate;

[0143] Performing a graphic imaging operation on the substrate to form a circuit layer on the substrate; performing an AOI optical inspection on the substrate, wherein the illumination intensity is 130Lx; turning off the light source of the AOI optical equipment, taking out the substrate, and obtaining imaging data of the substrate.

[0144] Example 6

[0145] Cutting the copper clad laminate to form a substrate;

[0146] The substrate is subjected to a needle brush grinding operation, wherein the grinding brush current is 1.0A;

[0147] Performing micro-etching on the substrate to increase the surface roughness of the substrate;

[0148] performing a cleaning operation on the substrate;

[0149] Performing a graphic imaging operation on the substrate to form a circuit layer on the substrate; performing an AOI optical inspection on the substrate, wherein the illumination intensity is 130Lx; turning off the light source of the AOI optical equipment, taking out the substrate, and obtaining imaging data of the substrate.

[0150] Comparative Example 1

[0151] Cutting the copper clad laminate to form a substrate;

[0152] The substrate is subjected to a non-woven cloth grinding operation, wherein the grinding brush current is 1.0A;

[0153] Performing micro-etching on the substrate to increase the surface roughness of the substrate;

[0154] performing a cleaning operation on the substrate;

[0155] Performing a graphic imaging operation on the substrate to form a circuit layer on the substrate;

[0156] Performing AOI optical inspection on the substrate, wherein the light intensity is 130Lx;

[0157] Turn off the light source of the AOI optical device, take out the substrate, and obtain the imaging data of the substrate.

[0158] Comparative Example 2

[0159] Cutting the copper clad laminate to form a substrate;

[0160] The substrate is subjected to a ceramic grinding operation, wherein the grinding brush current is 1.0A;

[0161] Performing micro-etching on the substrate to increase the surface roughness of the substrate;

[0162] performing a cleaning operation on the substrate;

[0163] Performing a graphic imaging operation on the substrate to form a circuit layer on the substrate;

[0164] Performing AOI optical inspection on the substrate, wherein the light intensity is 130Lx;

[0165] Turn off the light source of the AOI optical device, take out the substrate, and obtain the imaging data of the substrate.

[0166] The following are the results of AOI light source inspection after grinding the plates of each embodiment and comparative example, and the recorded results are shown in the following figure:

[0167] Example Brush Type Brush current Light intensity Recognition effect Example 1 Needle brush 0.6A 110Lx Can identify Example 2 Needle brush 0.8A 110Lx Can identify Example 3 Needle brush 1.0A 110Lx Can identify Example 4 Needle brush 0.6A 130Lx Can identify Example 5 Needle brush 0.8A 130Lx Can identify Example 6 Needle brush 1.0A 130Lx Can identify Comparative Example 1 Non-woven fabric 1.0A 130Lx Unrecognizable Comparative Example 2 ceramics 1.0A 130Lx Unrecognizable

[0168] It can be understood that the circuit board pretreatment process steps in Examples 1 to 6 are all the same. The difference between Examples 1 to 6 is the different grinding brush current and light intensity. However, the grinding brush current in Examples 1 to 6 is in the range of 0.6A-1.0A, and the light intensity is in the range of 110Lx-130 Lx. The color pictures obtained by AOI inspection after grinding the boards in Examples 1 to 6 are as follows: Figure 3 As shown, the picture is clear and can be recognized by AOI inspection equipment under normal light intensity.

[0169] Furthermore, the brush current and light intensity of Comparative Example 1 and Example 6 are the same. The difference between Comparative Example 1 and Example 6 is that the brush types used are different. The brush used in Comparative Example 1 is non-woven fabric. The color picture obtained by AOI inspection after grinding the plate in Comparative Example 1 is as follows: Figure 4 As shown, the image is blurry and overexposed under normal light intensity, making it unrecognizable by AOI inspection equipment.

[0170] Furthermore, the brush current and light intensity of Comparative Example 2 and Example 6 are the same. The difference between Comparative Example 2 and Example 6 is that the brush types used are different. The brush used in Comparative Example 2 is ceramic. The color picture obtained by AOI inspection after grinding the plate in Comparative Example 2 is as follows: Figure 5 As shown, the image is blurry and the substrate is dark under normal light intensity and cannot be recognized by the AOI inspection equipment.

[0171] In summary, the substrate is ground with a needle brush at a preset grinding current, making the copper surface of the substrate rough, thereby slowing down the copper surface reflection of the substrate in the AOI optical inspection process, so that the substrate can be recognized by the AOI inspection equipment under normal light intensity, thus avoiding the need to repeatedly debug the parameters of the AOI inspection equipment, thereby improving the inspection efficiency and production efficiency.

[0172] The above-mentioned embodiments only express several implementation methods of the present disclosure, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present disclosure, and these all belong to the protection scope of the present disclosure. Therefore, the protection scope of the patent of the present disclosure shall be subject to the attached claims.

Claims

1. A circuit board pre-processing process for a front-view camera of an automobile, characterized in that: The following steps are involved: Cutting the copper clad laminate to form a substrate; Performing a needle brush grinding operation on the substrate to roughen the surface of the substrate, wherein the grinding brush current is 0.6A-1.0A; Performing micro-etching on the substrate to increase the roughness of the surface of the substrate; performing a cleaning operation on the substrate; Performing a graphic imaging operation on the substrate to form a circuit layer on the substrate; The substrate is subjected to AOI optical inspection, wherein the light intensity is 110 Lx-130 Lx.

2. The circuit board pre-processing process for a front-view camera of an automobile according to claim 1, characterized in that: The substrate is subjected to a needle brush grinding operation, which specifically comprises the following steps: placing the substrate into a brushing machine so that the substrate is located between two needle brushes; The brushing machine is started, the substrate moves in a straight line, and the two needle brushes rotate relative to the substrate, and the rotation direction of the two needle brushes is opposite to the forward direction of the substrate.

3. The circuit board pre-treatment process for a front-view camera of an automobile according to claim 1, characterized in that: The substrate is subjected to a needle brush grinding operation to make the surface of the substrate rough, which specifically includes the following steps: The substrate is initially ground, the needle brush current is 0.6A-0.8A, and the needle brush rotation speed is 1600r / min-1800r / min.

4. The circuit board pre-treatment process for a front-view camera of an automobile according to claim 3, characterized in that: After the micro-etching operation is performed on the substrate and before the cleaning operation is performed on the substrate, the following steps are also included: The substrate is subjected to secondary grinding, the needle brush current is 0.9A-1.0A, and the needle brush rotation speed is 1200r / min-1300r / min.

5. The circuit board pre-processing process for a front-view camera of an automobile according to claim 4, characterized in that: The conveying direction of the substrate during the initial grinding is opposite to the conveying direction of the substrate during the secondary grinding; and, The direction of rotation of the needle brush during the initial grinding of the plate is opposite to the direction of rotation of the needle brush during the secondary grinding of the plate.

6. The circuit board pre-treatment process for a front-view camera of an automobile according to claim 1, characterized in that: The substrate is cleaned, specifically comprising the following steps: performing a first water washing operation on the substrate; Performing a pickling operation on the substrate; The substrate is subjected to a second water washing operation.

7. The circuit board pre-treatment process for a front-view camera of an automobile according to claim 1, characterized in that: The substrate is micro-etched, specifically comprising the following steps: The substrate is sprayed with an alkaline etching solution to increase the roughness of the substrate surface.

8. The circuit board pre-processing process for a front-view camera of an automobile according to claim 1, characterized in that: Performing a graphic imaging operation on the substrate specifically comprises the following steps: Performing a lamination operation on the substrate; performing an exposure operation on the substrate; performing a developing operation on the substrate; performing an etching operation on the substrate; The substrate is subjected to a film stripping operation to form a circuit layer on the substrate.

9. The circuit board pre-processing process for a front-view camera of an automobile according to claim 1, characterized in that: After the substrate is cleaned and before the substrate is imaged, the following steps are also included: The substrate is subjected to a baking operation.

10. A circuit board, characterized in that: The circuit board for a front-view camera of an automobile is prepared by using the pre-treatment process of the circuit board for a front-view camera of an automobile according to any one of claims 1 to 9.

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