Study on Corrosion Resistance of Metallized Quartz Glass
In the high-tech field, quartz glass has become an indispensable material due to its excellent performance, but its metallization process faces a thorny problem: how to make the metal layer resistant to corrosion in harsh environments and ensure the long-term reliability of devices.
Quartz glass has become a key material in high-end fields such as optical fiber communication, laser technology and semiconductor manufacturing due to its high light transmittance, high temperature resistance and corrosion resistance. But its “weakness” is also obvious: Low conductivity, surface vulnerable to environmental impact 。
To this end, scientists have developed quartz Glass metallization By depositing metal film on the surface of glass to enhance its functionality. But whether the metallized layer can maintain stability in various harsh environments, especially its corrosion resistance, directly determines the service life and reliability of the entire component.
01 Necessity of metallization
Although pure quartz glass has many advantages low conductivity and The surface is vulnerable to the environment The application in complex environment is limited by the characteristics of. Metallization technology perfectly solves these problems by depositing a layer of metal film on the surface of quartz glass.
The metallized layer not only endows quartz glass with good conductivity and thermal conductivity, but also improves the corrosion resistance and wear resistance of its surface. This technology transforms quartz glass from a “transparent substrate” to a “multi-functional carrier”, while maintaining its original optical performance advantages.
Commonly used metal materials include aluminum, silver, copper, etc. These metals can be uniformly deposited on the surface of quartz glass by physical vapor deposition (PVD), chemical vapor deposition (CVD), or sputtering.
02 Corrosion challenges and influencing factors
Metallized quartz glass is faced with many corrosion challenges in the process of use. thermal stability The first problem is that the difference in thermal expansion coefficient between the metal film and the glass substrate will lead to the accumulation of thermal stress and affect the metal adhesion.
For example, the thermal expansion coefficient of copper is 17 × 10 ⁻⁶⁶/℃, while that of quartz glass is only 5 × 10 ⁻⁶/℃. This difference will produce stress when the temperature changes, which may lead to cracking or peeling of the metal layer.
Chemical corrosion Is another big challenge. Some metals (such as aluminum) are easy to react with oxygen, water and acid-base environment, resulting in corrosion or oxidation. In alkaline environment, quartz glass itself can easily react with alkali to form soluble silicate.
Electrical reliability It cannot be ignored. The quality, thickness and surface flatness of the metal film directly affect its electrical performance. Any minor defect may lead to poor electrical connection and affect the performance of the whole device.
03 Technological innovation for improving corrosion resistance
In order to improve the corrosion resistance of metallized quartz glass, researchers have proposed a variety of innovative schemes. Optimization of interface bonding strength It is a key breakthrough point: by treating the surface of quartz glass with oxygen plasma, breaking the inert silicon oxygen bond and introducing hydroxyl (- OH), the bonding strength of the metal coating can be increased by more than 40%.
Transition layer design Is another important strategy. The titanium/nickel multilayer structure can alleviate the difference of thermal expansion coefficient between quartz glass and metal, and reduce the risk of interface cracking at high temperature.
The researchers also developed New corrosion resistant coating One method is to set scandium silicate coating and scandium fluoride coating on the surface of quartz glass. The combination of these two materials can provide a wider transmission range of ultraviolet light and better corrosion resistance in practical applications.
Another innovation is the use of modified polyimide as a corrosion resistant film. The film is based on polyimide, and yttrium nitride/hafnium borate composite microspheres are added as modifiers, which significantly enhance the alkali resistance, wear resistance and mechanical properties of quartz glass.
04 Test Methods and Performance Evaluation
Evaluation of the corrosion resistance of metallized quartz glass requires a variety of test methods. Thermal cycle test The adhesion, surface state and physical properties of the metal film were observed by repeatedly heating and cooling the samples in different temperature ranges.
Chemical corrosion test Expose the sample to different chemical reagents and observe the corrosion degree of its surface and the change of metal film. This test can evaluate the performance of metallized layer in harsh chemical environment.
Tensile and impact tests By applying mechanical force to the metallized quartz glass, the fracture, cracking and falling off of the metal film were observed. These tests are helpful to evaluate the mechanical durability and reliability of metal films in practical operation.
The results show that the corrosion resistance of nanocrystalline copper layer is good in 3.5% sodium chloride solution, and the corrosion solution will gradually enter the interface between the copper layer and the glass matrix along the pitting pit, resulting in the copper layer falling off.
In 10% sodium hydroxide solution, the corrosion rate of nanocrystalline copper layer is relatively high, and it will rapidly fail due to a large number of microcracks generated by stress corrosion.
05 Application prospect and future direction
The improvement of the corrosion resistance of metallized quartz glass opens up the possibility of its application in a variety of extreme environments. stay Optical communication field , metallized quartz glass substrate is used to integrate optical chip and electrical chip, and supports 400G/800G optical communication standard through low loss signal transmission.
stay Semiconductor manufacturing Metallized quartz glass can be used for electrical connection, heat dissipation and protection. It not only has good conductivity, but also can effectively improve thermal management and extend equipment life.
Aerospace and chemical processing Metallized quartz glass is also needed in the field, because it can enhance the performance in high temperature, high humidity or strong corrosive environment. For example, it can be used to manufacture high temperature resistant circuit boards, reactor components, etc., to ensure stable operation of equipment in extreme environments.
Future research will focus on Application of New Metal Materials Especially in extreme environments such as high temperature, high pressure and strong corrosion, high temperature and corrosion resistant metal materials will be the development trend.
Optimization of metallization process It is also the key point. How to reduce the defects of the metal film, improve the adhesion between the metal film and the glass substrate, and improve the uniformity and stability of the film will be the key to improve the reliability of the metallized quartz glass.
In the deep sea, the optical fiber sensor relying on metallized quartz glass has worked continuously for 5000 hours without performance attenuation, and the signal transmission error is less than 0.01%.
At 800 ℃, the new metallized coating remains stable and protects the quartz glass substrate from corrosion.
In the future, with the continuous advancement of material selection, process optimization and equipment innovation, quartz glass metallization technology will play an increasingly important role in the fields of microelectronics, precision instruments, photoelectric devices, etc.