Film uniformizing process for glue uniformizing orifice of porous base material

Abstract

The invention provides a glue uniformizing orifice film uniformizing process for a porous base material. The glue uniformizing orifice film uniformizing process comprises the following steps that S1, a rigid base material with micropores formed in the surface is provided; s2, the surface of the base material is subjected to glue uniformizing and curing, and an initial glue layer is formed; s3, applying a glue supplementing solution to the edge of the orifice of the micropore in a micro-dispensing manner to form an annular glue body surrounding the orifice; and S4, carrying out secondary homogenization treatment on the base material on which the annular colloid is formed, so that the annular colloid is spread and fused with the initial glue layer, and forming a glue film with uniform thickness in the orifice area. According to the method, after overall glue uniformizing is carried out, local accurate glue supplementing is carried out on the hole opening area, secondary uniformizing treatment is carried out, the siphon effect generated by negative pressure in a hole in the spin coating process is effectively counteracted, the thickness uniformity of a hole opening glue film is remarkably improved, and the problems that hole opening glue is thin and the bottom is leaked are fundamentally solved.

Description

Technical Field

[0001] This invention relates to the field of microstrip circuit product technology, and in particular to a uniform film coating process for perforated substrates. Background Technology

[0002] In the manufacturing of microelectronic and optoelectronic devices, high-rigidity substrates such as alumina and quartz are laser-drilled and then coated with photoresist through a spin coating process.

[0003] Existing technologies primarily employ spin coating, which relies on the centrifugal force generated by high-speed rotation to spread the adhesive. However, when applied to rigid substrates with micropores, this process suffers from significant drawbacks: high-speed rotation easily creates a stable negative pressure zone within the micropores, generating a "siphon effect" that continuously draws the adhesive from the orifice into the pores or micropores of the substrate. This fluid dynamic imbalance directly leads to thinning, unevenness, or even complete leakage of the adhesive film in the orifice area, severely impacting the accuracy of subsequent photolithography patterns and the electrical, optical, or structural reliability of the product. This has become a key technical bottleneck restricting the improvement of processing yield for such porous substrates. Summary of the Invention

[0004] To address the above problems, the present invention provides a process for uniformly coating and film distribution through the orifices of a porous substrate.

[0005] To solve the above problems, the technical solution adopted by the present invention is as follows: A process for uniformly coating perforated substrates includes the following steps: S1. Provide a rigid substrate with micropores formed on its surface; S2. Apply a uniform adhesive layer to the surface of the substrate and cure it to form an initial adhesive layer; S3. Apply a filler adhesive to the edge of the micropore opening using a micro-dispensing method to form an annular colloid around the opening; S4. The substrate on which the annular colloid is formed is subjected to a secondary homogenization treatment so that the annular colloid spreads and fuses with the initial adhesive layer, forming an adhesive film of uniform thickness in the orifice area.

[0006] Preferably, the secondary homogenization process in S4 includes a spin coating process and a micro-vibration leveling process performed sequentially.

[0007] Preferably, the spin coating process includes a first low-speed rotation stage and a second high-speed rotation stage; the rotation speed of the first low-speed rotation stage is 400-600 rpm and the time is 8-12 s; the rotation speed of the second high-speed rotation stage is 2500-3500 rpm and the time is 5-15 s.

[0008] Preferably, the vibration frequency of the micro-vibration leveling treatment is 60-120Hz, the displacement amplitude is 0.3-0.7mm, and the treatment time is 15-25s.

[0009] Preferably, the process further includes step S5: subjecting the film that has undergone secondary homogenization to a soft baking treatment, wherein the temperature of the soft baking treatment is 90-110°C and the time is 2-4 minutes.

[0010] Preferably, the width W of the annular colloid formed in S3 satisfies: W=k×D, where D is the diameter of the micropore and k is a coefficient with a value range of 0.4-0.6.

[0011] Preferably, the adhesive used in step S2 is selected according to the type of substrate; When the substrate is an alumina substrate, an adhesive with a viscosity range of 800-1200 mPa·s and a solid content of 35%-40% is selected; When the substrate is quartz, the adhesive solution with a viscosity range of 300-500 mPa·s, a solid content of 25%-30%, and containing 1.5%-2.0% silane coupling agent in total volume is selected.

[0012] Preferably, in step S3, a micro-dispensing machine is used for dispensing, the dispensing pressure is 0.1-0.3 MPa, and the diameter of the dispensing needle used is 1 / 4-1 / 2 of the diameter of the micropore.

[0013] Preferably, the rigid substrate in S1 is an alumina ceramic substrate or a quartz substrate, and the diameter of the micropores is 0.2-1 mm.

[0014] Preferably, during the spin coating process, the rotation speed and time of the second high-speed rotation stage are adjusted according to at least one of the following factors: substrate type, adhesive viscosity, and micropore diameter.

[0015] The beneficial effects of this invention are as follows: 1. This invention, by performing precise local glue replenishment and secondary homogenization treatment on the orifice area after overall homogenization, effectively counteracts the "siphon effect" generated by the negative pressure inside the orifice during spin coating, significantly improves the uniformity of the orifice film thickness, and fundamentally solves the problems of thin orifice film and leakage.

[0016] 2. This invention integrates two homogenization mechanisms: spin coating and micro-vibration leveling. First, centrifugal force is used to achieve macroscopic spreading and fusion of the adhesive, and then mechanical vibration is used to promote microscopic flow and redistribution of the adhesive. This smooths out the abrupt changes in film thickness caused by orifice steps and differences in substrate surface characteristics, and improves the process adaptability and process window for different substrates such as alumina and quartz. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating the operation of the present invention. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0019] Reference Figure 1 A process for uniformly coating perforated substrates includes the following steps: S1. Provide a rigid substrate with micropores formed on its surface; The substrate provided in this step is an alumina, quartz, or ferrite substrate that has undergone laser drilling, and the diameter of the micropores is 0.2-1 mm. The walls of the micropores and the surface of the substrate are pre-formed with a metal or ceramic thin film layer by magnetron sputtering.

[0020] S2. Apply a uniform adhesive layer to the surface of the substrate and cure it to form an initial adhesive layer; This step involves spin coating to apply the adhesive to the entire surface of the substrate. After coating, the adhesive layer is pre-baked to achieve initial curing, forming the initial adhesive layer. Different adhesive formulations are selected for different substrate types. When the substrate is an alumina substrate, a glue with a viscosity range of 800-1200 mPa·s and a solid content of 35%-40% is selected, and the glue system is a phenolic-diazo system or an acrylic system. When the substrate is a quartz substrate, a colloid with a viscosity range of 300-500 mPa·s and a solid content of 25%-30% is selected. The colloid contains 1.5%-2.0% of a silane coupling agent as a surface-active component.

[0021] S3. Apply a filler adhesive to the edge of the micropore opening using a micro-dispensing method to form an annular colloid around the opening; This step is performed using a micro-dispensing machine equipped with a fine-diameter dispensing needle. The dispensing pressure is 0.1-0.3 MPa, and the diameter of the dispensing needle used is 1 / 4-1 / 2 of the diameter of the micropore. The width W of the annular adhesive satisfies: W=k×D, where D is the diameter of the micropore, and k is a coefficient ranging from 0.4 to 0.6. By precisely controlling the dispensing path, the adhesive is deposited around the micropore opening to form a continuous and complete annular coating.

[0022] S4. The substrate on which the annular colloid is formed is subjected to a secondary homogenization treatment so that the annular colloid spreads and fuses with the initial adhesive layer, forming an adhesive film of uniform thickness in the orifice area. The secondary homogenization process includes sequential spin coating and micro-vibration leveling processes: Spin coating process: includes a first low-speed rotation stage and a second high-speed rotation stage; the rotation speed of the first low-speed rotation stage is 400-600 rpm, and the time is 8-12 s; the rotation speed of the second high-speed rotation stage is 2500-3500 rpm, and the time is 5-15 s. The rotation speed and time of the second high-speed rotation stage are adjusted according to at least one of the following factors: substrate type, adhesive viscosity, and micropore diameter.

[0023] Micro-vibration leveling treatment: vibration frequency of 60-120Hz, displacement amplitude of 0.3-0.7mm, and treatment time of 15-25s.

[0024] S5. Perform a soft baking treatment on the adhesive film that has completed the secondary homogenization process. The softening process is carried out at a temperature of 90-110°C for 2-4 minutes. The purpose of softening is to promote the evaporation of solvents in the adhesive film, stabilize the adhesive layer to fix its morphology, and at the same time avoid over-curing or cross-linking of the adhesive film.

[0025] This process systematically solves the problems of thin adhesive film at the orifice, leakage, and thickness fluctuations caused by the "siphon effect," "orifice step effect," and "substrate-adhesive interface mismatch" during the uniform coating process on rigid substrates drilled by lasers. These problems arise from the synergistic effect of three core steps: "precise local adhesive filling at the orifice," "centrifugal force-driven spreading and fusion," and "vibration-assisted secondary leveling." Specifically, the annular adhesive layer established in step S3 serves as a buffer and replenishment layer; the spin coating process in step S4 achieves large-scale redistribution and fusion of the adhesive; and the micro-vibration process precisely corrects microscopic inhomogeneities. Ultimately, a uniform and continuous adhesive film with the same thickness as the substrate planar area is obtained in the orifice region, significantly improving the accuracy of subsequent pattern transfer and product reliability.

Claims

1. A process for uniformly coating perforated substrates, characterized in that, Includes the following steps: S1. Provide a rigid substrate with micropores formed on its surface; S2. Apply a uniform adhesive layer to the surface of the substrate and cure it to form an initial adhesive layer; S3. Apply a filler adhesive to the edge of the micropore opening using a micro-dispensing method to form an annular colloid around the opening; S4. The substrate on which the annular colloid is formed is subjected to a secondary homogenization treatment so that the annular colloid spreads and fuses with the initial adhesive layer, forming an adhesive film of uniform thickness in the orifice area.

2. The uniform film coating process for a porous substrate according to claim 1, characterized in that, The secondary homogenization process in S4 includes a spin coating process and a micro-vibration leveling process performed sequentially.

3. The uniform film coating process for a porous substrate according to claim 2, characterized in that, The spin coating process includes a first low-speed rotation stage and a second high-speed rotation stage; the rotation speed of the first low-speed rotation stage is 400-600 rpm and the time is 8-12s; the rotation speed of the second high-speed rotation stage is 2500-3500 rpm and the time is 5-15s.

4. The uniform film coating process for a porous substrate according to claim 2, characterized in that, The vibration frequency of the micro-vibration leveling treatment is 60-120Hz, the displacement amplitude is 0.3-0.7mm, and the treatment time is 15-25s.

5. The uniform film coating process for a porous substrate according to claim 1, characterized in that, It also includes S5: performing a soft baking treatment on the adhesive film that has completed the secondary homogenization treatment, wherein the soft baking treatment temperature is 90-110°C and the time is 2-4 minutes.

6. The uniform film coating process for a porous substrate according to claim 1, characterized in that, The width W of the annular colloid formed in S3 satisfies: W=k×D, where D is the diameter of the micropore and k is a coefficient with a value range of 0.4-0.

6.

7. The uniform film coating process for a porous substrate according to claim 1, characterized in that, The adhesive used in S2 is selected according to the type of substrate; When the substrate is an alumina substrate, an adhesive with a viscosity range of 800-1200 mPa·s and a solid content of 35%-40% is selected; When the substrate is quartz, the adhesive solution with a viscosity range of 300-500 mPa·s, a solid content of 25%-30%, and containing 1.5%-2.0% silane coupling agent in total volume is selected.

8. The uniform film coating process for a porous substrate according to claim 7, characterized in that, In step S3, a micro-dispensing machine is used for dispensing, with a dispensing pressure of 0.1-0.3 MPa, and the diameter of the dispensing needle used is 1 / 4-1 / 2 of the diameter of the micropore.

9. The uniform film coating process for a porous substrate according to claim 1, characterized in that, The rigid substrate in S1 is an alumina ceramic substrate or a quartz substrate, and the diameter of the micropores is 0.2-1 mm.

10. The uniform film coating process for a porous substrate according to claim 3, characterized in that, During the spin coating process, the rotation speed and time of the second high-speed rotation stage are adjusted according to at least one of the following factors: substrate type, adhesive viscosity, and micropore diameter.

Images