In the process of MEMS evolving toward greater miniaturization and multifunctionality, the processing precision, interface compatibility, and functional integration at submicron scales pose strict challenges to materials. With their unique nano-molding capabilities, dielectric stability, and low-stress characteristics, silicone rubber and silicone oil have become the "molecular link" connecting micro-nano structures with macroscopic functions. From flexible substrates for sensors to driving media for actuators, from sealing layers for microfluidic chips to tunable components for RF devices, they are reshaping the manufacturing paradigm of MEMS through material innovation, providing key support for miniaturized intelligent systems.

一、Core Material Challenges in MEMS Manufacturing

(一) Processing Limits at Micro-Nano Scales

MEMS devices often incorporate three-dimensional structures ranging from tens to hundreds of microns. Traditional materials face three major bottlenecks in submicron processing:

• Inadequate Molding Resolution: The lithography precision of ordinary polymers hardly breaks through 1μm, failing to meet the requirements for nano-scale structures.
• Stress Concentration Issues: Thermal expansion differences at the interfaces of different materials cause warping deformation of microstructures after packaging.
• Interface Contamination Risks: Residues from the processing process easily affect the electrical and mechanical reliability of micro-devices.

Silicone rubber achieves nano-scale replication precision through soft lithography, and combined with supercritical drying technology, it can fabricate micro-nano structures with a porosity of up to 80%. As a sacrificial layer material, silicone oil can completely volatilize without residue at high temperatures, solving the contamination problem in microchannel release.

(二) Performance Requirements for Multi-Physical Field Compatibility

MEMS devices often need to meet multi-dimensional performance requirements such as electrical, mechanical, and optical properties. The dielectric constant of silicone rubber can be adjusted within the range of 2-10, and the viscosity of silicone oil can be matched to different fluid dynamic needs through molecular design, jointly achieving multi-physical field collaborative optimization at micro-nano scales.

二、Silicone Rubber: Structural Substrates and Functional Carriers for MEMS Devices

(一) Substrate Innovation for Flexible Sensors

Silicone rubber demonstrates unique advantages in flexible pressure sensors: embedding silver nanowire networks in PDMS substrates enables wide-range pressure detection from 0.1 to 10MPa, and its bionic skin structure achieves a tactile resolution of 0.1mm. Silicone rubber substrates added with carbon nanotubes show a resistance change rate of <5% after 100,000 bends, meeting the long-term use requirements of wearable devices.

(二) Packaging Breakthroughs for Microfluidic Chips

Silicone rubber-based microfluidic chips achieve breakthroughs through multi-layer bonding technology: silicone rubber treated with oxygen plasma has an interlayer bonding strength of up to 5N/cm, capable of withstanding fluid pressures of 100kPa. The micro-channels of silicone rubber surface-modified with hydrophilic groups have a water contact angle of less than 30°, solving the adhesion problem of biological samples. After a blood glucose meter chip applied this technology, the detection accuracy increased by 30%, and the sample consumption was reduced to less than 1μL.

三、Silicone Oil: Fluid Driving and Functional Regulation for MEMS Systems

(一) Driving Medium Innovation for Micro-Actuators

Silicone oil shows multiple values in dielectric elastomer actuators: its high dielectric constant can enhance the driving electric field strength, and low volatility ensures long-term operational stability. After a micro-pump is filled with silicone oil, the flow regulation range reaches 0.1-10μL/min, suitable for 微量 drug delivery scenarios. New magnetorheological silicone oil can instantaneously change its viscosity by 10 times under an applied magnetic field, enabling rapid response for micro-mechanical switches.

(二) Performance Optimization for RF MEMS

In RF devices, silicone oil as a tunable medium achieves breakthroughs: dynamically adjusting the dielectric constant of the resonator by controlling the filling amount of silicone oil through MEMS. After an RF filter adopted this technology, the central frequency tuning range increased to 20%. The low-loss characteristics of silicone oil reduce the insertion loss of RF signals to below 0.5dB, meeting the high-frequency requirements of 5G communications.

四、Future Innovation Directions for MEMS Materials

(一) R&D of Intelligent Responsive Micro-Structure Materials

Researchers are developing multi-stimulus responsive materials: photothermal-sensitive silicone rubber can produce local volume changes under laser irradiation for non-contact control of microvalves; pH-responsive silicone oil can automatically adjust its viscosity with pH in body fluid environments, suitable for implantable microfluidic systems.

(二) Heterogeneous Integration of Material-Process Innovation

New silicon-based materials are achieving cross-scale integration: using graphene-silicone rubber composites for MEMS electrodes to meet both conductivity and flexibility requirements; constructing nano-ceramic layers on the surface of silicone oil through atomic layer deposition to achieve functional integration of anti-fouling and low friction.

(三) Digital Manufacturing-Driven Material Innovation

Optimizing material design through machine learning: using neural networks to predict the micro-nano molding parameters of silicone rubber, reducing the structural defect rate from 20% to 5%; simulating the flow behavior of silicone oil in micro-channels based on digital twin technology to optimize the device flow field design in advance, shortening the R&D cycle by 40%.
From smartphone accelerometers to implantable sensors, silicone rubber and silicone oil are driving the iterative upgrading of MEMS technology through material innovation. They are not only the cornerstone of micro-nano structure construction but also the key medium for multifunctional integration. With the development of the Internet of Things and intelligent manufacturing, these silicon-based materials will continue to break through in cutting-edge fields such as micro energy harvesting, lab-on-a-chip, and bio-MEMS, providing unlimited possibilities for the widespread application of miniaturized intelligent devices.



Modified Platinum Catalyst MY PC41-49-Mingyi Silicone