In the realms of electronic information and high-end manufacturing, the tide of miniaturization and integration is driving industrial innovation. As the "photolithography soul of chip manufacturing," photomasks face unprecedented challenges in processing precision and reliability. Traditional techniques struggle with bottlenecks like thermal damage, mechanical stress deformation, and cost-yield tradeoffs when handling high-density interdigitated electrodes and ultra-fine patterns (hollowed structures). MONO LASER’s femtosecond laser processing is now rewriting the manufacturing paradigm with disruptive advantages.
Interdigitated electrodes are critical structures in photomasks—also known as photomasks, reticles, or lithography masks. Serving as the master pattern for photolithography, they act like the "film negative" in traditional photography, encoding the precise design of electronic circuits. During lithography, light passes through the photomask’s transparent regions to project patterns onto silicon wafers or panels coated with photoresist. After development and etching, these patterns are replicated onto the substrate. From the layout of billions of transistors in chips to the micron-scale pixel arrays in displays, photomasks bridge the gap between "design" and "manufacturing."
Manufacturing interdigitated electrodes—key components of photomasks—poses multiple challenges:
Accuracy-Efficiency Paradox:
Slow wire electrical discharge machining (EDM) can achieve high precision by using a moving fine metal wire as an electrode to erode material via electrical discharge. However, electrode wear leads to declining edge roughness over time, compromising quality.
Material Adaptability Limits:
Insulating materials like silicon carbide and aluminum oxide ceramics cannot be processed by traditional electrical methods, limiting application scope.
Yield-Cost Pressures:
Electron beam (EB) technology can bypass optical diffraction limits to write nanoscale patterns via thermal or ionization effects, but its exorbitant equipment costs (requiring vacuum systems and electron gun maintenance) and low throughput restrict it to master mask fabrication, unsuitable for mass production.
In "sub-mask processing" (e.g., mass production of interdigitated electrodes and hollow patterns), Monochromatic Technology’s femtosecond laser technology delivers unique advantages:
Defect-Free Forming via Cold Processing
Femtosecond lasers (pulse width < 500fs) achieve instantaneous material vaporization with ultra-short pulse energy, creating a near-zero heat-affected zone (HAZ). This eliminates ablation carbonization and stress deformation—problems plaguing traditional methods. For ultra-complex geometries, fine slit cutting, or micro-holes, femtosecond lasers outperform nanosecond lasers and electrical processing in precision. In molybdenum electrode machining, they achieve 0.005mm feature width with burr-free, crack-free, deformation-free cuts, ensuring dimensional accuracy of ±1μm to meet stringent edge quality requirements.
2. Full Material Compatibility Expands Application Frontiers
Femtosecond laser processing transcends material limitations, efficiently and consistently machining high-hardness ceramics (hardness > HV1500), highly reflective metal foils (stainless steel, molybdenum, copper), and flexible substrates (PET, PI). Case Study: Precision etching of interdigitated electrode patterns on stainless steel tubes achieves a minimum width of 92±1μm, roughness < Ra0.4, with no carbonization or burrs. Etching depth of 0.4–1μm avoids damaging internal insulators, demonstrating versatility across material types.
As microelectronics advance toward micron-level integration, photomasks remain pivotal. Every breakthrough in their processing technology reshapes industry possibilities. Monochromatic Technology’s femtosecond laser solutions not only solve the challenge of "how to machine finer," but also balance precision and efficiency through process innovation—enabling China’s photomasks to evolve into mass-producible "industrial-grade ultra-precision devices."
Monochromatic Technology Femtosecond Laser Precision Cutting Equipment
