Method for improving metalized binding force of quartzite by combining strong cleaning with glass transition layer

Abstract

The invention provides a method for improving metalized binding force of quartzite by combining strong cleaning with a glass transition layer. The method comprises the following steps: S1, pre-cleaning a quartzite substrate; s2, a SiO2 glass transition layer is deposited on the surface of the cleaned quartzite substrate through magnetron sputtering; s3, carrying out annealing and curing treatment on the substrate on which the SiO2 glass transition layer is deposited; s4, sequentially depositing a TiW adhesion layer and a Cu functional layer on the surface of the cured SiO2 glass transition layer; and S5, carrying out spin coating, exposure, development, electroplating thickening and etching on the Cu functional layer to form a metalized pattern. By introducing the strong chemical cleaning step, trace metal impurities on the surface of the quartz stone can be specifically and efficiently removed, the substrate surface with ultrahigh cleanliness and high surface energy is obtained, and weak binding force points caused by interface pollution are fundamentally eliminated.

Description

Technical Field

[0001] This invention relates to the field of quartz stone treatment technology, and in particular to a method for improving the metallization bonding strength of quartz stone through strong cleaning and bonding with a glass transition layer. Background Technology

[0002] Quartz glass (quartz stone) has important applications in advanced packaging, optical communication, and aerospace due to its excellent high-frequency characteristics, thermal stability, and insulation properties. Achieving reliable surface metallization is crucial for manufacturing related components. Currently, the mainstream technology uses magnetron sputtering, first depositing a metal such as titanium (Ti) or chromium (Cr) as an adhesion layer on the quartz glass surface, and then depositing a functional metal layer (such as copper).

[0003] Existing quartz glass surfaces exhibit high chemical inertness, and traditional adhesive layers primarily rely on physical adsorption or the formation of weak chemical bonds to bond with it, resulting in weak intrinsic interfacial adhesion. Under temperature variations or high-temperature operating environments, the significant difference in thermal expansion coefficients between the metal and glass can easily lead to thermal mismatch stress at the interface, causing a significant decrease in adhesion or even film peeling, severely restricting the application of devices in high-temperature, high-reliability scenarios. Summary of the Invention

[0004] To address the above problems, this invention provides a method for improving the metallization bonding strength of quartz stone through strong cleaning combined with a glass transition layer.

[0005] To solve the above problems, the technical solution adopted by the present invention is as follows: A method for improving the metallization bonding strength of quartz stone by strong cleaning and bonding a glass transition layer includes the following steps: S1. Perform pre-cleaning on the quartz substrate; S2. A SiO2 glass transition layer is deposited by magnetron sputtering on the cleaned quartz substrate surface; S3. Anneal and cure the substrate with the SiO2 glass transition layer deposited. S4. A TiW adhesion layer and a Cu functional layer are sequentially deposited on the surface of the cured SiO2 glass transition layer. S5. Spin coat, expose, develop, electroplating thicken and etch on Cu functional layer to form metallized pattern; Step S1 also includes: S11, Strong chemical cleaning, using chemical reagents that can thoroughly remove metallic impurities from the surface of quartz stone and improve its surface energy.

[0006] Preferably, S11 specifically involves immersing and cleaning the quartz substrate with aqua regia.

[0007] Preferably, aqua regia is prepared by mixing concentrated hydrochloric acid and concentrated nitric acid in a volume ratio of 3:1, and the cleaning conditions are: soaking at room temperature for 30 minutes.

[0008] Preferably, step S1 further includes: performing ultrasonic cleaning with acetone and methanol in sequence before the strong chemical cleaning step; and performing ultrasonic cleaning with isopropanol, rinsing with deionized water, drying with nitrogen and drying at 150°C in sequence after the strong chemical cleaning step.

[0009] Preferably, in step S2, an RF magnetron sputtering method is used to deposit a SiO2 glass transition layer. The deposition parameters are: Ar gas pressure 3-8 mTorr, RF power 150-300 W, and the thickness of the deposited SiO2 glass transition layer is 30-80 nm.

[0010] Preferably, the thickness of the SiO2 glass transition layer is 40-60 nm.

[0011] Preferably, in step S3, the annealing and curing process conditions are as follows: in an air or oxygen atmosphere, the temperature is increased to 300°C at a rate of 5°C / min and held for 30 minutes.

[0012] Preferably, in step S4, before depositing the TiW adhesion layer, the surface of the SiO2 glass transition layer is first subjected to O2 plasma activation treatment.

[0013] Preferably, in step S4, a TiW adhesion layer is deposited by magnetron sputtering, wherein the atomic ratio of Ti to W in the TiW adhesion layer is 10:90, and its deposition thickness is 20-25 nm.

[0014] Preferably, in step S4, the thickness of the Cu functional layer deposited by magnetron sputtering is 500-600 nm.

[0015] The beneficial effects of this invention are as follows: 1. By introducing a strong chemical cleaning step, especially aqua regia treatment, trace amounts of metallic impurities on the surface of quartz stone can be specifically and efficiently removed, resulting in a substrate surface with ultra-high cleanliness and high surface energy, fundamentally eliminating weak points in the bonding force caused by interface contamination.

[0016] 2. By magnetron sputtering deposition combined with annealing and curing, a chemically compatible SiO2 glass transition layer was constructed on a quartz substrate, which formed a strong interface with the substrate through covalent bonding. At the same time, it provided a highly active and stable bonding substrate for subsequent metal layers, realizing a fundamental transformation of interface bonding from physical adsorption to chemical bonding. Attached Figure Description

[0017] Figure 1 Parameter graphs for different experimental variables in this invention; Figure 2This is a parameter diagram for different thickness ranges 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 1-2 A method for improving the metallization bonding strength of quartz stone through strong cleaning and a glass transition layer, comprising the following steps: S1. Perform pre-cleaning on the quartz substrate; S2. A SiO2 glass transition layer is deposited by magnetron sputtering on the cleaned quartz substrate surface; S3. Anneal and cure the substrate with the SiO2 glass transition layer deposited. S4. A TiW adhesion layer and a Cu functional layer are sequentially deposited on the surface of the cured SiO2 glass transition layer. S5. Spin coat, expose, develop, electroplat, and etch on the Cu functional layer to form a metallized pattern.

[0020] Step S1 includes the following sub-steps: S11. Strong Chemical Cleaning: This step involves treating the quartz stone surface with a chemical reagent capable of thoroughly removing metallic impurities and increasing its surface energy. Specifically, this strong chemical cleaning step involves immersing the quartz stone substrate in aqua regia. Aqua regia, through its oxidizing components, oxidizes the metallic elements on the quartz stone surface into ionic states. Simultaneously, its acid radical components form soluble complexes with the metal ions, effectively dissolving and removing the adhering metals and their oxide impurities. Furthermore, the strong oxidizing properties of aqua regia simultaneously decompose residual organic pollutants. After this treatment, the quartz stone surface cleanliness is significantly improved, and the surface energy increases, resulting in a reduced contact angle and enhanced hydrophilicity.

[0021] Pretreatment before strong chemical cleaning: Before the strong chemical cleaning step, a dual-solvent ultrasonic cleaning process using acetone and methanol is performed sequentially. This process aims to remove most of the organic grease and contaminants from the quartz stone surface.

[0022] Post-cleaning treatment with strong chemical cleaning: Following the strong chemical cleaning step, the substrate undergoes sequential ultrasonic cleaning with isopropanol, rinsing with deionized water, nitrogen blowing, and drying. This process removes aqua regia residue and other impurities introduced during the cleaning process, resulting in a dry and clean substrate surface.

[0023] In step S2, the SiO2 glass transition layer is deposited using RF magnetron sputtering technology. The deposition process is carried out in an inert gas atmosphere, and the deposition rate and density of the film are controlled by adjusting the sputtering power and gas pressure. The deposited SiO2 glass transition layer has an amorphous structure, and its function is to establish an intermediate layer with matching composition and structure between the quartz substrate and the subsequent metal layer. The thickness of this transition layer must ensure that the film is continuous, dense, and free of pinhole defects, thereby providing a uniform and complete substrate for subsequent interfacial bonding.

[0024] In step S3, the substrate with the deposited SiO2 glass transition layer is annealed and cured. This annealing process is carried out in an oxygen-containing atmosphere using programmed temperature control. Annealing has multiple benefits: First, it promotes relaxation and atomic rearrangement of the metastable amorphous SiO2 film deposited by sputtering, thereby eliminating internal stress, reducing porosity, and improving film density and stability. Second, under high temperature, a chemical reaction occurs between the SiO2 glass transition layer and the quartz substrate interface, forming covalent bonds through dehydration condensation and other mechanisms, achieving a transformation from physical adhesion to chemical bonding, greatly enhancing the interfacial bonding strength between the transition layer and the substrate. Third, the annealed SiO2 transition layer surface exposes more active dangling bonds and hydroxyl groups, providing high-density reaction sites for subsequent bonding with the metal adhesion layer.

[0025] Step S4 specifically includes: Surface activation: Before depositing the TiW adhesion layer, the surface of the annealed and cured SiO2 glass transition layer is subjected to O2 plasma activation treatment. This treatment further cleans the surface and increases its chemical activity.

[0026] Depositing the TiW Adhesive Layer: A TiW alloy was deposited as an adhesive layer on the activated surface using magnetron sputtering. Due to its high chemical reactivity, the Ti component in the TiW alloy readily forms strong chemical bonds with the oxygen elements on the SiO2 transition layer surface, thus establishing a robust interfacial bond. The addition of the W component improves the structural and thermal stability of the adhesive layer. The composition and thickness of this adhesive layer must balance interfacial bonding strength and stress matching.

[0027] Cu functional layer deposition: A Cu layer as a conductive functional layer is deposited on top of the TiW adhesive layer using magnetron sputtering. This Cu layer serves as a seed layer, providing a conductive substrate for subsequent electroplating thickening steps.

[0028] In summary, this method ensures ultra-high cleanliness and activity of the starting surface through strong chemical cleaning. A chemically bondable stable interface is constructed on the quartz substrate by depositing and annealing a SiO2 glass transition layer. A TiW adhesion layer of a specific composition is then deposited to achieve strong chemical bonding with the transition layer and buffer thermal stress. Finally, the metallization process is completed using conventional patterning techniques. This method systematically solves the core problems of weak interfacial bonding and large thermal mismatch in quartz metallization.

Claims

1. A method for improving the metallization bonding strength of quartz stone through strong cleaning and a glass transition layer, characterized in that, Includes the following steps: S1. Perform pre-cleaning on the quartz substrate; S2. A SiO2 glass transition layer is deposited by magnetron sputtering on the cleaned quartz substrate surface; S3. Anneal and cure the substrate with the SiO2 glass transition layer deposited. S4. A TiW adhesion layer and a Cu functional layer are sequentially deposited on the surface of the cured SiO2 glass transition layer. S5. Spin coat, expose, develop, electroplating thicken and etch on Cu functional layer to form metallized pattern; Step S1 also includes: S11, Strong chemical cleaning, using chemical reagents that can thoroughly remove metallic impurities from the surface of quartz stone and improve its surface energy.

2. The method for improving the metallization bonding strength of quartz stone by strong cleaning and bonding a glass transition layer according to claim 1, characterized in that, S11 specifically refers to: soaking and cleaning the quartz substrate with aqua regia.

3. The method for improving the metallization bonding strength of quartz stone by strong cleaning and bonding a glass transition layer according to claim 2, characterized in that, Aqua regia is made by mixing concentrated hydrochloric acid and concentrated nitric acid in a volume ratio of 3:

1. The cleaning conditions are: soaking at room temperature for 30 minutes.

4. The method for improving the metallization bonding strength of quartz stone by strong cleaning and bonding a glass transition layer according to claim 1, characterized in that, Step S1 further includes: before the strong chemical cleaning step, performing dual-solvent ultrasonic cleaning with acetone and methanol in sequence; after the strong chemical cleaning step, performing ultrasonic cleaning with isopropanol, rinsing with deionized water, blowing with nitrogen and drying at 150°C in sequence.

5. The method for improving the metallization bonding strength of quartz stone by strong cleaning and bonding a glass transition layer according to claim 1, characterized in that, In step S2, an RF magnetron sputtering method is used to deposit a SiO2 glass transition layer. The deposition parameters are: Ar gas pressure 3-8 mTorr, RF power 150-300 W, and the thickness of the deposited SiO2 glass transition layer is 30-80 nm.

6. The method for improving the metallization bonding strength of quartz stone by strong cleaning and bonding a glass transition layer according to claim 5, characterized in that, The thickness of the SiO2 glass transition layer is 40-60 nm.

7. The method for improving the metallization bonding strength of quartz stone by strong cleaning and bonding a glass transition layer according to claim 1, characterized in that, In step S3, the annealing and curing process conditions are as follows: in an air or oxygen atmosphere, the temperature is increased to 300°C at a rate of 5°C / min and held for 30 minutes.

8. The method for improving the metallization bonding strength of quartz stone by strong cleaning and bonding a glass transition layer according to claim 1, characterized in that, In step S4, before depositing the TiW adhesion layer, the surface of the SiO2 glass transition layer is first subjected to O2 plasma activation treatment.

9. A method for improving the metallization bonding strength of quartz stone by strong cleaning and bonding a glass transition layer according to claim 1 or 8, characterized in that, In step S4, a TiW adhesion layer is deposited by magnetron sputtering. The atomic ratio of Ti to W in the TiW adhesion layer is 10:90, and its deposition thickness is 20-25 nm.

10. The method for improving the metallization bonding strength of quartz stone by strong cleaning and bonding a glass transition layer according to claim 1, characterized in that, In step S4, the Cu functional layer deposited by magnetron sputtering has a thickness of 500-600 nm.

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