Special vacuum etching machine for DBC (Direct Bonding Copper) ceramic copper-clad substrate

Abstract

The invention discloses a vacuum etching machine special for a DBC ceramic copper-clad substrate, and belongs to the technical field of etching machines, the vacuum etching machine comprises a main etching chamber, an upper chamber is arranged on the main etching chamber in a communicating manner, a perforated plate is arranged at the top of the main etching chamber, the top of the upper chamber is in dome type design, and an etching liquid spraying mechanism is arranged in the upper chamber. The annular main pipeline is adopted, the annular main pipeline forms an isobaric ring structure, liquid medicine circularly flows in the annular main pipeline after being injected from the symmetrical liquid inlets, the pressure difference between a starting point and an ending point is eliminated, and static pressure at any point on the annular main pipeline is basically equal; vortex mixers are arranged at the tail ends of the main spraying branches and the auxiliary spraying branches, it is ensured that chemical concentration and temperature of liquid medicine sprayed out of any nozzle are uniform microcosmically, the liquid medicine is actively sucked at a bubble generation source based on the Bernoulli principle, and the bubble generation effect is improved. And a porous plate is arranged to physically divide the main etching chamber into two independent spaces.

Description

Technical Field

[0001] This invention belongs to the field of etching machine technology, specifically a vacuum etching machine for DBC ceramic copper-clad substrates. Background Technology

[0002] The DBC ceramic copper-clad substrate vacuum etching machine is a high-precision processing equipment used to manufacture core components for high-power electronic modules. By performing etching operations in a vacuum environment, it completely eliminates problems such as residual copper and severe side etching caused by bubble adhesion in traditional processes. It can process ultra-high precision circuit patterns with fine linewidths and steep sidewalls with an extremely high etching factor (≥3.0), significantly improving the product yield, consistency, and reliability of DBC substrates. It is a key piece of equipment to meet the miniaturization and high efficiency development requirements of next-generation power electronic devices.

[0003] The existing technology still has the following shortcomings: 1. Uneven distribution of etching solution leads to inconsistent etching rates. Existing equipment mainly uses asymmetrical branching pipelines with "T" or "tree branch" shapes. After the etching solution flows out of the main pump, it flows through branching pipelines with different lengths, number of bends, and angles, resulting in significant differences in flow resistance among the branches. The direct consequence of this is that the nozzle outlet pressure and mass flow rate are uneven at different locations, the etching rate at the edge and center of the substrate is significantly different, and the linewidth consistency is affected.

[0004] 2. Layering of drug components and temperature leads to uneven activity. During long-distance transport and temporary storage of etching solutions, due to density differences, fresh solutions and deposited solutions are prone to stratification. Furthermore, due to the heat exchange effect, there is significant heat exchange between the pipeline and the external environment, resulting in a more uneven heat distribution of the solution in the pipeline. This causes the activity of the solution sprayed from the nozzle to fluctuate continuously.

[0005] 3. The spray kinetic energy and the vacuum airflow interfere with each other. The existing equipment integrates the spraying system and the vacuum system at the top of the chamber. The high-speed liquid jet sprayed downwards directly clashes with the high-speed airflow upwards, causing eddies, vortices and droplet splashing, which disrupts the stability of the flow field. This results in some areas having excessively rapid liquid replenishment, while other areas have insufficient liquid replenishment. Summary of the Invention

[0006] To overcome the above-mentioned defects, the present invention provides a dedicated vacuum etching machine for DBC ceramic copper-clad substrates, which solves the problems of the prior art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a vacuum etching machine for DBC ceramic copper-clad substrates, including a main etching chamber, an upper chamber connected to the main etching chamber, a perforated plate on the top of the main etching chamber, a dome-shaped design on the top of the upper chamber, an etching solution spraying mechanism in the upper chamber, and substrate moving mechanisms on both sides of the main etching chamber. The etching solution spraying mechanism includes an annular main pipe disposed in the upper chamber. The annular main pipe has two liquid inlets, the distance between the two liquid inlets being the diameter of the annular main pipe. The annular main pipe has main spray branches and auxiliary spray branches distributed radially at equal intervals. The main spray branches and auxiliary spray branches are arranged alternately. A vortex mixer is connected to one end of the main spray branch and auxiliary spray branch facing the center of the annular main pipe. The main spray branch and auxiliary spray branch are tangentially connected to the vortex mixer. A nozzle is connected to the bottom of the vortex mixer through a flange. The flow channel of the nozzle has a "converging-expanding" structure.

[0008] As a further aspect of the present invention, the top of the upper chamber is provided with multiple vacuum pumping ports.

[0009] As a further aspect of the present invention: the substrate moving mechanism includes a drive housing fixedly connected to both sides of the main etching chamber, and a pair of rotating seats are fixedly connected to both sides of the main etching chamber, with a worm gear rotatably connected between each pair of rotating seats.

[0010] As a further aspect of the present invention: two rows of worm gears are rotatably arranged on both sides of the main etching chamber, and the two rows of worm gears are distributed on both sides of the corresponding worm, and the worm meshes with the worm gears.

[0011] As a further embodiment of the present invention: the worm gear and the worm are both located inside the drive housing, and a servo motor is fixedly connected to one side of the drive housing, with the output end of the servo motor being coaxially and fixedly connected to the worm.

[0012] As a further aspect of the present invention: two rows of material conveying rollers are rotatably connected to the inner walls on both sides of the main etching chamber, and the material conveying rollers are coaxially and fixedly connected to the worm gear on the corresponding side.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention uses a ring-shaped main pipe, which itself forms an isobaric ring structure. After the liquid is injected from the symmetrical inlet, it forms a circulating flow in the ring-shaped main pipe, eliminating the pressure difference between the starting point and the ending point. This makes the static pressure at any point on the ring-shaped main pipe basically equal. Moreover, the main spray branches and auxiliary spray branches are equidistantly distributed and have a mirror symmetrical structure with highly consistent flow resistance characteristics. Branches with the same flow resistance drawn from the same isobaric source ensure that the flow rate and hydraulic pressure distributed to each nozzle are absolutely uniform. The inherent uniformity based on the principle of fluid mechanics is achieved through mechanical structure, rather than relying entirely on sensors for adjustment later.

[0014] 2. This invention sets up vortex mixers at the ends of each main spray branch and auxiliary spray branch. The etching solution enters the cylindrical chamber tangentially, generating a high-speed swirling flow. Centrifugal force causes the slightly denser components to move towards the outer wall, but stronger shear force and turbulence thoroughly disperse and mix all components (including fluid clusters at different temperatures). The solution undergoes final mixing just before being sprayed, ensuring that the chemical concentration and temperature of the solution sprayed from any nozzle are microscopically uniform, fundamentally eliminating the activity differences caused by stratification.

[0015] 3. Traditional top-vacuuming is a "long-distance" macroscopic suction, with limited suction power for micron-sized bubbles attached to the substrate surface and circuit sidewalls. These "stubborn" bubbles are the root cause of side etching and rough etched surfaces. This invention, based on Bernoulli's principle, creates a strong local low-pressure zone as the etching solution passes through the nozzle throat. Active suction is applied at the source of bubble generation. Furthermore, a perforated plate physically divides the main etching chamber into two independent spaces, completely decoupling the spraying and vacuuming systems. The turbulence caused by the spraying is confined to the lower layer and cannot penetrate the distribution plate to interfere with the vacuuming efficiency of the upper layer. The vacuuming system smoothly removes the gas passing through the perforations from the upper layer, achieving a non-interfering effect. Attached Figure Description

[0016] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a three-dimensional structural diagram of the upper chamber of the present invention; Figure 3 This is a three-dimensional internal structure diagram of the present invention; Figure 4 This is a three-dimensional internal structure diagram of the vortex mixer of the present invention; Figure 5 This is a three-dimensional internal structure diagram of the substrate moving mechanism of the present invention; Figure 6 This is a three-dimensional internal structure diagram of the nozzle of the present invention.

[0017] In the diagram: 1. Main etching chamber; 2. Upper chamber; 3. Perforated plate; 4. Annular main pipe; 5. Liquid inlet; 6. Main spray branch; 7. Secondary spray branch; 8. Vortex mixer; 9. Nozzle; 10. Vacuum extraction port; 11. Rotary seat; 12. Worm gear; 13. Worm wheel; 14. Servo motor; 15. Feed roller; 16. Drive housing. Detailed Implementation

[0018] The technical solution of this patent will be further described in detail below with reference to specific embodiments.

[0019] like Figures 1-6 As shown, the present invention provides a technical solution: A dedicated vacuum etching machine for DBC ceramic copper-clad substrates includes: The main etching chamber 1 is connected to the upper chamber 2. The top of the main etching chamber 1 is provided with a perforated plate 3. The top of the upper chamber 2 is designed as a dome. An etching liquid spraying mechanism is provided inside the upper chamber 2. Substrate moving mechanisms are provided on both sides of the main etching chamber 1. The perforated plate 3 separates the main etching chamber 1 from the upper chamber 2. The dome design on the top of the upper chamber 2 is a smooth arc surface design, which avoids airflow dead angles and facilitates the convergence of gas to the exhaust port to form an optimal aerodynamic shape. The etching solution spraying mechanism includes an annular main pipe 4 disposed within the upper chamber 2. Two inlets 5 are provided on the annular main pipe 4, the distance between the two inlets 5 being the diameter of the annular main pipe 4. Main spray branches 6 and secondary spray branches 7 are equidistantly distributed radially along the annular main pipe 4, alternating between the main spray branches 6 and secondary spray branches 7. A vortex mixer 8 is connected to the end of each main spray branch 6 and secondary spray branch 7 facing the center of the annular main pipe 4. Both the main spray branches 6 and secondary spray branches 7 are tangentially connected to the vortex mixer 8. A nozzle 9 is connected to the bottom of the vortex mixer 8 via a flange. The flow channel of the nozzle 9 has a "converging-expanding" structure. Multiple vacuum extraction ports 10 are provided at the top of the upper chamber 2. A three-way valve is installed in chamber 2. The input end of the three-way valve is connected to the main circulation pump, and the two output ends are connected to the two liquid inlets 5 respectively. The etching solution can be pumped into the annular main pipe 4 from the two symmetrical points (liquid inlets 5). The etching solution is filled into the entire flow channel system from two directions simultaneously in the annular main pipe 4. Since it is a closed loop, the pressure at each point in the annular main pipe 4 will automatically tend to be balanced. There is no concept of "inlet" and "end" of the traditional straight pipe. The entire annular main pipe 4 itself is an isobaric source. Furthermore, since the main spray branch 6 and the secondary spray branch 7 are alternately and equidistantly arranged, the environment at the end of each branch is basically the same. Therefore, the pressure and flow rate of the etching solution distributed to each branch are inherently uniform. After the etching solution flows out from the end of the main spray branch 6 or the secondary spray branch 7, it is tangentially pumped into the vortex mixer 8 and rotates at high speed along the inner wall of the cylindrical chamber of the vortex mixer 8, generating centrifugal force. Etching solutions with different densities and temperatures are forced to mix. After the density and temperature are homogenized, they are finally sprayed out from the nozzle 9. This solves the problem of component and temperature stratification caused by long pipeline transportation. Secondly, the "converging-expanding" flow channel structure within nozzle 9 indicates that nozzle 9 is a Venturi nozzle. When high-pressure liquid passes through, a local low-pressure zone is generated at the throat of nozzle 9. This low-pressure zone actively draws in the surrounding gaseous environment. This means that each nozzle 9 not only sprays liquid but also creates a tiny "auxiliary vacuum" effect near its nozzle orifice. This structure converts the spray kinetic energy into the potential energy of local suction, actively processing bubbles from the spray source (nozzle 9). Combined with the negative pressure generated by the vacuum pumping port 10, this greatly improves the efficiency of microbubble removal. The substrate moving mechanism includes a drive housing 16 fixedly connected to both sides of the main etching chamber 1. A pair of rotating seats 11 are fixedly connected to both sides of the main etching chamber 1, and a worm gear 12 is rotatably connected between each pair of rotating seats 11. Two rows of worm wheels 13 rotatably rotate on both sides of the main etching chamber 1, distributed on both sides of the corresponding worm gear 12. The worm gear 12 meshes with the worm wheels 13. The worm wheels 13 and the worm gear 12 are all located inside the drive housing 16. A servo motor 14 is fixedly connected to one side of the drive housing 16, and the output end of the servo motor 14 is coaxially fixedly connected to the worm gear 12. Two rows of material conveying rollers 15 are rotatably connected to the inner walls of both sides of the main etching chamber 1. The feeding roller 15 is coaxially and fixedly connected to the worm gear 13 on the corresponding side. The main purpose of the substrate moving mechanism is to transport the copper-clad ceramic substrate. The two ends of the main etching chamber 1 are provided with notches to facilitate the entry and exit of the copper-clad ceramic substrate. At the same time, segmented sealed tunnels are required at both notches to ensure their airtightness (not shown in the figure). When the two servo motors 14 are started synchronously, the worm gear 12 connected to its output end can rotate, and each worm gear 13 meshing with the worm gear 12 can rotate. The two rows of worm gears 13 on the corresponding side rotate in opposite directions. At the same time, the feeding roller 15 rotates in opposite directions. The copper-clad ceramic substrate is clamped in the middle and can be moved.

[0020] The working principle of this invention is as follows: A three-way valve is installed in the upper chamber 2. The input end of the three-way valve is connected to the main circulation pump, and the two output ends are connected to the two liquid inlets 5 respectively. The etching solution can be pumped into the annular main pipe 4 from the two symmetrical points (liquid inlets 5). The etching solution is filled into the entire flow channel system from two directions simultaneously in the annular main pipe 4. Since it is a closed loop, the pressure at each point in the annular main pipe 4 will automatically tend to be balanced. There is no concept of "inlet" and "end" in the traditional straight pipe. The entire annular main pipe 4 itself is an isobaric source. Furthermore, since the main spray branch 6 and the secondary spray branch 7 are alternately and equidistantly arranged, the environment at the end of each branch is basically the same. Therefore, the pressure and flow rate of the etching solution distributed to each branch are inherently uniform. After the etching solution flows out from the end of the main spray branch 6 or the secondary spray branch 7, it is tangentially pumped into the vortex mixer 8 and rotates at high speed along the inner wall of the cylindrical chamber of the vortex mixer 8, generating centrifugal force. Etching solutions with different densities and temperatures are forced to mix. After the density and temperature are homogenized, they are finally sprayed out from the nozzle 9. This solves the problem of component and temperature stratification caused by long pipeline transportation. The perforated plate 3 separates the main etching chamber 1 from the upper chamber 2. The dome-shaped design at the top of the upper chamber 2 is a smooth arc design, which avoids dead angles of airflow and facilitates the convergence of gas to the exhaust port, forming the optimal aerodynamic shape. Secondly, the "converging-expanding" flow channel structure within nozzle 9 indicates that nozzle 9 is a Venturi nozzle. When high-pressure liquid passes through, a local low-pressure zone is generated at the throat of nozzle 9. This low-pressure zone actively draws in the surrounding gaseous environment. This means that each nozzle 9 not only sprays liquid but also creates a tiny "auxiliary vacuum" effect near its nozzle orifice. This structure converts the spray kinetic energy into the potential energy of local suction, actively processing bubbles from the spray source (nozzle 9). Combined with the negative pressure generated by the vacuum pumping port 10, this greatly improves the efficiency of microbubble removal. Finally, the main purpose of the substrate moving mechanism is to transport the copper-clad ceramic substrate. The two ends of the main etching chamber 1 are provided with notches to facilitate the entry and exit of the copper-clad ceramic substrate. At the same time, segmented sealed tunnels are provided at both notches to ensure their airtightness (not shown in the figure). When the two servo motors 14 are started synchronously, the worm gear 12 connected to its output end can rotate, and each worm wheel 13 meshing with the worm gear 12 can rotate. The two rows of worm wheels 13 on the corresponding side rotate in opposite directions. At the same time, the rotation of the material conveying roller 15 is also in opposite directions. The copper-clad ceramic substrate is clamped in the middle and can be moved.

[0021] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A vacuum etching machine for DBC ceramic copper clad substrate, characterized in that, Include: The main etching chamber (1) is provided with an upper chamber (2) in communication, the top of the main etching chamber (1) is provided with a multi-hole plate (3), the top of the upper chamber (2) is designed as a dome, an etching liquid spraying mechanism is arranged in the upper chamber (2), and a substrate moving mechanism is arranged on both sides of the main etching chamber (1); The etching liquid spraying mechanism comprises a ring-shaped main pipeline (4) arranged in the upper chamber (2), two liquid inlets (5) are formed in the ring-shaped main pipeline (4), the distance between the two liquid inlets (5) is the diameter length of the ring-shaped main pipeline (4), the ring-shaped main pipeline (4) is equidistantly distributed with a main spraying branch (6) and a secondary spraying branch (7) along the radial direction, the main spraying branch (6) and the secondary spraying branch (7) are alternately arranged, one end of the main spraying branch (6) and the secondary spraying branch (7) towards the center of the ring-shaped main pipeline (4) is in communication with a vortex mixer (8), the main spraying branch (6) and the secondary spraying branch (7) are tangentially inserted into the vortex mixer (8), and the bottom of the vortex mixer (8) is in communication with a nozzle (9) through a flange plate.

2. The DBC ceramic copper clad substrate dedicated vacuum etching machine according to claim 1, characterized in that: A plurality of vacuum air outlet ports (10) are arranged on the top of the upper chamber (2).

3. The DBC ceramic copper clad substrate dedicated vacuum etching machine according to claim 2, characterized in that: The substrate moving mechanism comprises a driving housing (16) fixedly connected to both sides of the main etching chamber (1), a pair of rotating seats (11) are fixedly connected to both sides of the main etching chamber (1), and a worm (12) is rotatably connected between each pair of rotating seats (11).

4. The DBC ceramic copper clad substrate dedicated vacuum etching machine according to claim 3, characterized in that: Two rows of worm gears (13) are rotatably arranged on both sides of the main etching chamber (1), and the two rows of worm gears (13) are arranged on both sides of the corresponding worm (12).

5. The DBC ceramic copper clad substrate dedicated vacuum etching machine according to claim 4, characterized in that: The worm gears (13) and the worm (12) are located in the driving housing (16), one side of the driving housing (16) is fixedly connected with a servo motor (14), and the output end of the servo motor (14) is coaxially fixedly connected with the worm (12).

6. The DBC ceramic copper clad substrate dedicated vacuum etching machine according to claim 5, characterized in that: Two rows of material conveying rollers (15) are rotatably connected to the inner walls on both sides of the main etching chamber (1), and the material conveying rollers (15) are coaxially fixedly connected with the corresponding worm gears (13).

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