CN115020191A - Circuit board production method - Google Patents

Abstract

The present invention is a circuit board production method, comprising the following steps: S1, rough cleaning the surface of a wafer for etching the circuit board; S2, placing the rough cleaned wafer into a vacuum chamber, and vacuuming the vacuum chamber, The vacuum degree range in the vacuum chamber is 5pa‑2pa; S3, inert gas is introduced into the vacuum chamber, and the speed range of the inert gas is 10‑5000sccm, and the graphite electrode is energized, and the energization voltage range is 200‑5000v; complete one cleaning In the present invention, the graphite electrode is used as the target source to ionize the inert gas and the active gas, which solves the problem of damage to the surface of the circuit board caused by the metal electrode as the target source, and effectively improves the surface dyne value of the circuit board; The surface of the circuit board is cleaned by the gas and the active gas at the same time, so that the oxidation rate of the surface film of the circuit board after cleaning can reach 99.9%, and the surface of the wafer is cleaned twice to ensure the surface cleanliness of the wafer and improve the use effect of the circuit board. .

Description

A kind of circuit board production method

technical field

The invention relates to the technical field of circuit boards, in particular to a method for producing circuit boards.

Background technique

Circuit board refers to the silicon wafer used to make silicon semiconductor circuits, and its original material is silicon. High-purity polysilicon is dissolved and mixed with silicon crystal seeds, and then slowly pulled out to form cylindrical monocrystalline silicon. At present, the domestic circuit board production lines are mainly 8 inches and 12 inches. The main processing methods of circuit boards are sheet processing and batch processing, that is, one or more circuit boards are processed at the same time. As semiconductor feature sizes become smaller and processing and measurement equipment becomes more and more advanced, new data characteristics appear in circuit board processing. At the same time, the reduction of the feature size increases the influence of the number of particles in the air on the quality and reliability of the circuit board after processing during circuit board processing. With the improvement of cleanliness, the number of particles also has new data characteristics.

In the prior art, when cleaning the surface of the circuit board, metal electrodes are often used, and the metal electrodes are oxidized in the active gas atmosphere, ionized under high voltage, and impact on the surface of the circuit board, resulting in poor surface cleanliness of the circuit board. Poor, and because the ion beam is mostly frontal impact, it cannot effectively clean both sides of the circuit board.

SUMMARY OF THE INVENTION

In view of this, the present invention aims to propose a circuit board production method to solve the problem that metal electrodes are often used in the surface cleaning of circuit boards. Ionization, impact on the surface of the circuit board, resulting in poor surface cleanliness of the circuit board.

In order to achieve the above object, the technical scheme of the present invention is achieved in this way:

A method for producing a circuit board, comprising the following steps:

S1. Roughly clean the surface of the etched circuit board wafer;

S2. Place the roughly cleaned wafer into a vacuum chamber, and evacuate the vacuum chamber, and the vacuum degree in the vacuum chamber is 5pa-2pa;

S3. Inert gas is introduced into the vacuum chamber, the speed range of the inert gas is 10-5000sccm, constant temperature cooling water is introduced into the graphite electrode, the cage with the substrate is rotated at a high speed, and the cylindrical target is rotated at the same time, and the magnetic field faces the substrate. The material passes through the insulating electrode, and the negative high voltage of the power supply is connected to the graphite electrode, and the graphite electrode is energized, and the energization voltage range is 200-5000v;

S4, introducing active gas into the vacuum chamber, the speed range of introducing active gas is 10-5000sccm, the cleaning time is 0.5-2h, and one cleaning is completed;

S5. Place the wafer after one cleaning into a vacuum chamber. The vacuum chamber is provided with an isolation plate. The isolation plate divides the vacuum chamber into an inert gas chamber and an active gas chamber. The vacuum chamber is evacuated, and the vacuum degree in the vacuum chamber is within the range 5pa-2pa;

S6. Inert gas is introduced into the inert gas chamber, and the speed range of the inert gas is 10-5000sccm, and the active gas is introduced into the active gas chamber, and the speed of the active gas is 10-5000sccm;

S7, energize the graphite electrodes in the inert gas chamber and the active gas chamber respectively, and the energization voltage range is 200-5000v;

S8. Rotate the wafer from the inert gas chamber to the active gas chamber, the rotation speed range is 0.2-0.6r/min, the cleaning time is 1.5-2h, and the secondary cleaning is completed;

S9, patterning and etching are performed on the cleaned wafer surface.

Preferably, the rough cleaning of the wafer surface in the step S1 is to put the circuit board in an NMP solution for degumming to remove colloidal objects on the surface of the circuit board.

Preferably, in the step S2, a turret is arranged in the vacuum chamber, and the turret drives the circuit board to rotate from the inert gas chamber to the active gas chamber.

Preferably, in the step S3 and the step S6, the inert gas is any one of helium, neon, argon, krypton, xenon, and radon.

Preferably, the active gas in the step S4 and the step S6 is oxygen.

Preferably, the etching step in the step S9 is to use a resin system of a specific shape; use a mold that matches the shape of the circuit board and the wiring pattern on the circuit board; put the resin system in the mold; pass the mold The shape of the circuit board and the wiring pattern on the circuit board are directly cast or molded; the conductive material is filled on the wiring pattern to form the circuit board conductive pattern.

Compared with the prior art, the circuit board production method of the present invention has the following advantages:

1. The graphite electrode is used as the target source to ionize the inert gas and the active gas, which solves the problem of damage to the surface of the circuit board caused by the metal electrode as the target source, and effectively improves the surface dyne value of the circuit board;

2. The use of inert gas and active gas to clean the surface of the circuit board at the same time can make the oxidation rate of the surface film of the circuit board reach 99.9% after cleaning;

3. Clean the wafer surface twice to ensure the surface cleanliness of the wafer and improve the use effect of the circuit board.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the accompanying drawings of the embodiments of the present invention will be briefly introduced hereinafter. The accompanying drawings are only used to illustrate some embodiments of the present invention, but not to limit all the embodiments of the present invention thereto.

1 is a flow chart of circuit board cleaning in Embodiment 4 of the present invention;

2 is a diagram of a circuit board cleaning device in Embodiment 4 of the present invention;

FIG. 3 is a state diagram of material distribution in the circuit board cleaning process of the present invention;

4 is a schematic diagram of the circuit board cleaning system of the present invention;

FIG. 5 is a schematic diagram of the ion distribution area in the cleaning system of the present invention.

Reference number:

1. Main body; 2. Cavity; 3. Vacuum pump set; 4. Isolation plate; 5. Flexible joint; 6. Turret; 7. Graphite electrode; 8. Inert gas box; 9. Solenoid valve; 10. Vacuum degree Detector; 11. High voltage power supply; 12. Active gas box.

Detailed ways

In order to make the above objects, features and advantages of the present invention more clearly understood, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Example 1:

A method for producing a circuit board, comprising the following steps:

S1, put the wafer surface for etching circuit board into NMP solution for degumming;

S2, place the wafer after rough cleaning into a vacuum chamber, and evacuate the vacuum chamber, and the vacuum degree in the vacuum chamber is 5pa;

S3. Pour argon gas into the vacuum chamber at a speed of 10 sccm, and energize the graphite electrode, and the energization voltage is 200v;

S4. Pour oxygen into the vacuum chamber at a rate of 10sccm and a cleaning time of 0.5h to complete one cleaning;

S5. Place the wafer after one cleaning into a vacuum chamber. The vacuum chamber is provided with an isolation plate. The isolation plate divides the vacuum chamber into an inert gas chamber and an active gas chamber, and evacuates the vacuum chamber. The vacuum degree in the vacuum chamber is 5pa;

S6, feed argon gas into the inert gas chamber, the speed of feeding argon gas is 10sccm, and feeding oxygen into the active gas chamber, the speed of feeding oxygen gas is 10sccm;

S7, energize the graphite electrodes in the inert gas chamber and the active gas chamber respectively, and the energization voltage is 200v;

S8, rotate the wafer from the inert gas chamber to the active gas chamber, the rotation speed is 0.2r/min, the cleaning time is 1.5h, and the secondary cleaning is completed;

S9, the wafer after cleaning is etched, and the etching step is to use a resin system of a specific shape; adopt a mold that matches the shape of the circuit board and the wiring pattern on the circuit board; place the above-mentioned resin system in the above-mentioned mold; The mold directly casts or presses the shape of the circuit board and the wiring pattern on the circuit board; and the wiring pattern is filled with conductive material to form the circuit board conductive pattern.

Embodiment 2:

On the basis of Embodiment 1, the circuit board production method of Embodiment 1 is further optimized:

A method for producing a circuit board, comprising the following steps:

S1, put the wafer surface for etching circuit board into NMP solution for degumming;

S2. Place the wafer after rough cleaning into a vacuum chamber, and evacuate the vacuum chamber, and the vacuum degree in the vacuum chamber is 4pa;

S3. Pour argon into the vacuum chamber at a rate of 500sccm, energize the graphite electrode, and energize at a voltage of 500v;

S4. Pour oxygen into the vacuum chamber at a rate of 500sccm and a cleaning time of 1h to complete one cleaning;

S5. Place the wafer after one cleaning into a vacuum chamber. The vacuum chamber is provided with an isolation plate. The isolation plate divides the vacuum chamber into an inert gas chamber and an active gas chamber, and evacuates the vacuum chamber. The vacuum degree in the vacuum chamber is 4pa;

S6, feed argon into the inert gas chamber, and the speed of feeding argon is 500 sccm, and feeding oxygen into the active gas chamber, and the speed of feeding oxygen is 500 sccm;

S7, energize the graphite electrodes in the inert gas chamber and the active gas chamber respectively, and the energization voltage is 500v;

S8. Rotate the wafer from the inert gas chamber to the active gas chamber, the rotation speed is 0.5r/min, the cleaning time is 1.5h, and the secondary cleaning is completed;

S9, the wafer after cleaning is etched, and the etching step is to use a resin system of a specific shape; adopt a mold that matches the shape of the circuit board and the wiring pattern on the circuit board; place the above-mentioned resin system in the above-mentioned mold; The mold directly casts or presses the shape of the circuit board and the wiring pattern on the circuit board; and the wiring pattern is filled with conductive material to form the circuit board conductive pattern.

Embodiment three:

On the basis of Embodiment 1, the circuit board production method of Embodiment 1 is further optimized:

A method for producing a circuit board, comprising the following steps:

S1, put the wafer surface for etching circuit board into NMP solution for degumming;

S2. Put the wafer after rough cleaning into a vacuum chamber, and vacuumize the vacuum chamber, and the vacuum degree in the vacuum chamber is 3pa;

S3. Pour argon gas into the vacuum chamber at a speed of 2500sccm, and energize the graphite electrode, and the energization voltage is 2500v;

S4. Pour oxygen into the vacuum chamber at a rate of 2500sccm and a cleaning time of 2h to complete one cleaning;

S5. Place the wafer after one cleaning into a vacuum chamber. The vacuum chamber is provided with an isolation plate. The isolation plate divides the vacuum chamber into an inert gas chamber and an active gas chamber, and evacuates the vacuum chamber. The vacuum degree in the vacuum chamber is 3pa;

S6, feed argon into the inert gas chamber, the speed of feeding argon is 2500sccm, and feeding oxygen into the active gas chamber, the speed of feeding oxygen is 2500sccm;

S7, energize the graphite electrodes in the inert gas chamber and the active gas chamber respectively, and the energization voltage is 3000v;

S8. Rotate the wafer from the inert gas chamber to the active gas chamber, the rotation speed is 0.4r/min, the cleaning time is 2h, and the secondary cleaning is completed;

S9, the wafer after cleaning is etched, and the etching step is to use a resin system of a specific shape; adopt a mold that matches the shape of the circuit board and the wiring pattern on the circuit board; place the above-mentioned resin system in the above-mentioned mold; The mold directly casts or presses the shape of the circuit board and the wiring pattern on the circuit board; and the wiring pattern is filled with conductive material to form the circuit board conductive pattern.

Embodiment 4:

On the basis of Embodiment 1, the circuit board production method of Embodiment 1 is further optimized:

A method for producing a circuit board, comprising the following steps:

S1, put the wafer surface for etching circuit board into NMP solution for degumming;

S2. Place the wafer after rough cleaning into a vacuum chamber, and evacuate the vacuum chamber, and the vacuum degree in the vacuum chamber is 2pa;

S3. Pour argon gas into the vacuum chamber at a speed of 5000sccm, and energize the graphite electrode, and the energization voltage is 5000v;

S4. Pour oxygen into the vacuum chamber at a rate of 5000sccm and a cleaning time of 2h to complete one cleaning;

S5. Place the wafer after one cleaning into a vacuum chamber. The vacuum chamber is provided with an isolation plate. The isolation plate divides the vacuum chamber into an inert gas chamber and an active gas chamber, and evacuates the vacuum chamber. The vacuum degree in the vacuum chamber is 2pa;

S6, feed argon gas into the inert gas chamber, the speed of feeding argon gas is 5000sccm, and feeding oxygen into the active gas chamber, the speed of feeding oxygen gas is 5000sccm;

S7, energize the graphite electrodes in the inert gas chamber and the active gas chamber respectively, and the energization voltage is 5000v;

S8, rotate the wafer from the inert gas chamber to the active gas chamber, the rotation speed is 0.2r/min, the cleaning time is 2h, and the secondary cleaning is completed;

S9, the wafer after cleaning is etched, and the etching step is to use a resin system of a specific shape; adopt a mold that matches the shape of the circuit board and the wiring pattern on the circuit board; place the above-mentioned resin system in the above-mentioned mold; The mold directly casts or presses the shape of the circuit board and the wiring pattern on the circuit board; and the wiring pattern is filled with conductive material to form the circuit board conductive pattern.

The isolation plate 4 divides the vacuum chamber into an inert gas chamber and an active gas chamber, the flexible joint 5 seals the turret and the isolation plate 4, and places the cleaned parts on the turret 6, so the The vacuum pump group 3 first evacuates the cavity 2 of the main body 1, so that the cavity 2 is a vacuum cavity 2; For detection, cleaning can be performed under different vacuum degrees according to different parts, and then the graphite electrode 7 is electrically connected to the high-voltage power supply 11 to form an alternating electric field in the cavity 2, and then the inert gas box is passed through the inert gas box. 8 and the active gas box 12 introduce inert gas and active gas into the cavity 2, the solenoid valve 9 controls the ventilation speed of the inert gas and the active gas, and the isolation plate 4 isolates the cavity 2 , so that the two sides of the isolation plate 4 are respectively in an inert gas atmosphere and an active gas atmosphere. In the inert gas atmosphere, the inert gas can be helium, neon, argon, etc., which can be selected according to production requirements, and the graphite electrode is in the electric field. A large number of electrons are emitted to the grounded anode under the action of the air, and they collide with argon and oxygen in the vacuum to generate ionization to generate plasma. The plasma bombards and cleans the residue on the surface of the circuit board. Contaminants, use plasma bombardment to clean the surface of the circuit board, ion bombardment cleaning is green and non-destructive cleaning, and because the plasma volume is smaller than water molecules, it can penetrate deep into the micro-holes and interior of the circuit board to complete the cleaning, improving the cleaning effect; in an active gas atmosphere Inside, the positive ions are accelerated to hit the graphite electrode to generate a sputtering reaction, and the graphite electrode reacts with the active gas. The sputtered substance reacts with oxygen and oxygen ions in the vacuum to form oxygen compounds and bombards the surface of the circuit board. Part of the oxygen It is ionized by high pressure to generate ozone, and the generated ozone has a strong oxidation reaction with the residue on the surface of the circuit board, and an oxidation product is generated on the surface of the circuit board. The oxidation product is bombarded by the plasma and separated from the surface of the circuit board, thereby achieving the purpose of auxiliary cleaning, and The negative ions accelerate to hit the circuit board and react with C and CC that have not completed the oxidation. The CO2 and CO generated by the reaction bombard and clean the surface of the circuit board. All the above substances finally exist in the form of gas or electrons, so there is no residue or Very little residue, so as to achieve the purpose of cleaning;

The resin system is physically mixed, and after mixing evenly, the temperature is raised for semi-curing. After semi-curing to a certain extent, the molten state of the resin system is maintained, and orderly reinforcing materials are added. The side of the free-standing mold that is in contact with the resin system is coated with a release agent, and the molten resin system is poured into a free-standing mold that matches the shape of the cleaned wafer and the wiring pattern on the circuit board, so that the molten resin system The mixture of solution and reinforcing material is completely cured by thermal curing in the independent mold, and the heating temperature is between 120°C and 150°C to separate the fully cured resin system from the independent mold. At this time, the shape of the resin system meets the requirements of the circuit board. The outer shape and the surface of the resin system are formed with wiring patterns, the mold release agent on the wafer surface is removed, and conductive materials are filled on the wiring patterns directly formed by the independent mold to form the circuit board wiring patterns.

The results of the surface dyne value and film oxidation rate of the circuit board after cleaning in Test Example 1-4 are shown in Table 1:

Table 1

Dyne value Film oxidation rate (%) Example 1 58 97.5 Embodiment 2 60 98.9 Embodiment 3 over 60 99.9 Embodiment 4 over 60 99.9

After the circuit board is treated by the cleaning method of this embodiment, the dyne value of the surface cleanliness can reach 60, and the oxidation rate of the film layer can reach 99.9%, which effectively improves the effect of cleaning the surface of the circuit board.

Although the present invention is disclosed above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be based on the scope defined by the claims.

Claims (6)

1. a circuit board production method, is characterized in that, comprises the following steps: S1. Roughly clean the surface of the etched circuit board wafer; S2. Place the roughly cleaned wafer into a vacuum chamber, and evacuate the vacuum chamber, and the vacuum degree in the vacuum chamber is 5pa-2pa; S3. Inert gas is introduced into the vacuum chamber, the speed range of the inert gas is 10-5000sccm, constant temperature cooling water is introduced into the graphite electrode, the cage with the substrate is rotated at a high speed, and the cylindrical target is rotated at the same time, and the magnetic field faces the substrate. The material passes through the insulating electrode, and the negative high voltage of the power supply is connected to the graphite electrode, and the graphite electrode is energized, and the energization voltage range is 200-5000v; S4, introducing active gas into the vacuum chamber, the speed range of introducing active gas is 10-5000sccm, the cleaning time is 0.5-2h, and one cleaning is completed; S5. Place the wafer after one cleaning into a vacuum chamber. The vacuum chamber is provided with an isolation plate. The isolation plate divides the vacuum chamber into an inert gas chamber and an active gas chamber. The vacuum chamber is evacuated, and the vacuum degree in the vacuum chamber is within the range 5pa-2pa; S6. Inert gas is introduced into the inert gas chamber, and the speed range of the inert gas is 10-5000sccm, and the active gas is introduced into the active gas chamber, and the speed of the active gas is 10-5000sccm; S7, energize the graphite electrodes in the inert gas chamber and the active gas chamber respectively, and the energization voltage range is 200-5000v; S8. Rotate the wafer from the inert gas chamber to the active gas chamber, the rotation speed range is 0.2-0.6r/min, the cleaning time is 1.5-2h, and the secondary cleaning is completed; S9, patterning and etching are performed on the cleaned wafer surface. 2. a kind of circuit board production method according to claim 1, is characterized in that, in described step S1, wafer surface rough cleaning is to put circuit board in NMP solution and carry out degumming to remove the glue on circuit board surface object. 3 . The method for producing a circuit board according to claim 1 , wherein a turret is arranged in the vacuum chamber in the step S5 , and the turret drives the circuit board to rotate from the inert gas chamber to the active gas chamber. 4 . . 4. A kind of circuit board production method according to claim 1, is characterized in that, in described step S3 and described step S6 inert gas is any one in helium, neon, argon, krypton, xenon, radon gas . 5 . The method for producing a circuit board according to claim 1 , wherein the active gas in the step S4 and the step S6 is oxygen. 6 . 6. A kind of circuit board production method according to claim 1, is characterized in that, in described step S9, etching step is to use resin system of specific form; Adopt and match with the shape of circuit board and wiring pattern on circuit board The above-mentioned resin system is placed in the above-mentioned mold; the shape of the circuit board and the wiring pattern on the circuit board are directly cast or molded through the mold; the conductive material is filled on the wiring pattern to form the circuit board conductive pattern.

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