The spotlight, like a fixed star, converged on the center of the stage. Below lay a silent sea—the gaze of the global technology, industry, and investment communities intertwined with anticipation, scrutiny, and an ineffable complexity. On this night in 2030, the Shanghai International Convention Center had become a sanctuary for humanity's precision industrial civilization. Xiuxiu stood on the stage, dressed in a deep space‑blue gown, its shoulder line as sharp as the guideway of a lithography machine. She carried no thick technical white paper, prepared no dazzling slide presentation; the enormous circular screen behind her remained a calm, dark void.
"Ladies and gentlemen," her voice emerged through the microphone, clear and steady, like a precisely calibrated laser. "Tonight, we should be celebrating a number—global market share first." She paused briefly, her gaze sweeping across the familiar and unfamiliar faces below. "But I would like to invite you, for a moment, to forget the numbers."
She turned aside and nodded slightly toward the control console. Instantly, the circular screen lit up—not with the expected brilliant data charts, but with a somewhat grainy, historically textured video. In the frame was a simple laboratory from the year 201X, a bulky deep ultraviolet (DUV) lithography machine prototype, its casing even showing patches of discoloration.
"This is where we began." Xiuxiu's voice became the narration, calmly guiding everyone's thoughts back in time.
The camera zoomed in on the light source system of that first‑generation DUV machine. The footage had the unsteady feel of being shot with a handheld camera from those years. "A mercury lamp light source," Xiuxiu explained, her voice carrying no pride, only an immersive reminiscence. "Its principle is to use high‑voltage discharge between electrodes to excite mercury vapor, generating specific wavelengths of ultraviolet light—primarily the g‑line (436nm) and i‑line (365nm). Wavelength determines the resolution ceiling. It was stable but bulky and energy‑intensive, like a steam engine from the Industrial Revolution—powerful, but not refined enough." In the footage, engineers gathered around the lamp, which emitted a dim yellow light, their faces a mixture of anxiety and hope. Countless ignition tests, page after page of densely written records—failures, adjustments, more failures.
The scene switched to a schematic of an excimer laser, dynamically illustrating how an argon‑fluoride (ArF) gas mixture was stimulated to emit 193nm deep ultraviolet light. "When we turned to the ArF excimer laser, it meant we were beginning our march toward shorter wavelengths and higher resolutions. But along with that came a host of challenges: laser stability, line‑width compression, energy control. Every percentage point increase in power, every picosecond of pulse stability, was bought with countless sleepless nights." In the footage, a younger Xiuxiu in anti‑static clothing pointed at the jumping waveform on an oscilloscope, engaged in intense discussion with her team. Even then, her eyes already held the tenacious gleam they carried today.
"Then, we encountered our first real bottleneck—the Rayleigh criterion." On the screen appeared the formula that would determine the destiny of lithography: CD = k₁ * λ / NA. Xiuxiu traced it in the air with an imaginary pen, as if giving everyone a fundamental lesson. "Resolution CD is proportional to wavelength λ and inversely proportional to numerical aperture NA. When λ was stuck at 193nm, we seemed to hit a ceiling. But human wisdom lies in finding a way out within the constraints of physical law." The footage transitioned to a close‑up of a water droplet, glistening between the lens and the silicon wafer.
"Immersion lithography was such a way out. Why water? Because water's refractive index n is about 1.44. When light travels from the lens (usually fused silica, n≈1.56) into water, its speed decreases according to n = c/v, and the effective wavelength λ shortens to λ₀/n. For 193nm light, the effective wavelength in water becomes 134nm. This seemingly simple step required precise control of fluid dynamics—how to ensure that droplet of ultrapure water remains stable during high‑speed scanning, with no bubbles, no contamination, constant temperature, perfectly adhering to both wafer and lens without causing any disturbance? This was not just an optical problem; it was an interdisciplinary challenge spanning materials science, chemistry, and precision mechanics." The footage showed early failures of the immersion system: water films rupturing, wafers contaminated, the team's faces etched with frustration. But it also recorded the moment a stable water film was first achieved—the brief, almost disbelieving silence in the lab, followed by an eruption of cheers.
The documentary's rhythm accelerated with the pace of technological advancement. DUV lithography machines ran steadily on production lines, etching ever‑finer circuits. But everyone before the screen knew this was far from the end. The visual tone grew austere, the background music punctuated with urgent drumbeats. The scene shifted to the early days of EUV research and development.
"When we decided to take on Extreme Ultraviolet (EUV), we knew it wasn't just a matter of changing a light source—it meant entering an entirely new realm of physics." On the screen appeared a complex schematic illustrating the laser‑produced plasma (LPP) process. "At 13.5nm, this extreme ultraviolet light is strongly absorbed by almost any material. We could no longer use lenses; only mirrors. And it had to propagate in vacuum, because air would absorb it." The footage showed the construction of vacuum chambers, the stringent cleanliness requirements.
"How do we generate 13.5nm light? We use high‑power carbon‑dioxide lasers to precisely bombard tin droplets falling tens of thousands of times per second." Slow‑motion footage showed the moment a laser pulse struck a tin droplet: the droplet was instantly vaporized and ionized, forming a high‑temperature plasma that radiated extreme ultraviolet light including the 13.5nm wavelength. "This process involves fluid mechanics, plasma physics, and laser‑matter interactions. Controlling the droplet size, speed, spacing, and the laser's pulse shape, energy, and timing—any slight deviation in any parameter meant a sharp drop in source power and a surge in debris, which would contaminate and damage the expensive Bragg reflectors." These were multilayer structures formed by alternating dozens of layers of molybdenum/silicon thin films, each layer controlled to nanometer precision. Through constructive interference, they achieved reflectivity above 70% for 13.5nm light, while reflectivity for other wavelengths remained extremely low. The very manufacture of such mirrors was an art at the nanometer scale.
The footage documented the team's long struggle to increase EUV source power: from tens of watts to one hundred, then approaching two hundred… Each small increment was accompanied by immense hardship. Xiuxiu appeared frequently—in labs, conference rooms, supplier production lines. We saw her brow furrow over an embargo on a critical optical component, and we saw her smile with approval when the team proposed an innovative dual‑pulse laser technology (first using a pre‑pulse to flatten the tin droplet into a disc‑like shape that more efficiently absorbed energy, then using the main pulse to excite it).
"Power, bandwidth, and collection efficiency—these three parameters together determine the throughput of the lithography machine: the number of wafers processed per hour. Without sufficient throughput, no matter how high the resolution, the machine is just a laboratory toy." Xiuxiu's voice remained steady, but everyone could feel the pressure accumulated over those years. The frame froze at the moment the EUV source power finally broke through the 250‑watt threshold. There were no cheers in the lab, only a long silence. Then someone began to sob quietly, others slumped to the floor, while Xiuxiu stared fixedly at the data curve. Only after confirming it had stabilized did she slowly close her eyes and exhale a long, deep breath.
The documentary's final section turned to the more advanced high‑numerical‑aperture (High NA) EUV. A schematic appeared, showing an exaggerated objective lens with greater curvature. "NA = n sinθ. To increase NA, we either increase the refractive index n—we already used water in immersion lithography; finding a liquid with an even higher refractive index is one path—or we increase the aperture angle θ, which means designing and manufacturing larger, more precise lenses approaching theoretical limits." The footage showed the challenges of manufacturing such large‑aperture lenses: aberration control, stress‑induced micro‑deformations, matching coefficients of thermal expansion… each one was an engineering Everest. In the footage, Xiuxiu's team introduced a real‑time thermal‑deformation compensation system, using piezoelectric actuators to dynamically adjust the mirror shape on a nanometer scale, counteracting the thermal load from the high‑power light source.
"This battle is not just about the lithography machine itself." Xiuxiu's voice sounded again, and the documentary's scope began to expand, revealing a vast industrial chain. "From the design of EDA software, to the manufacture of mask blanks (EUV uses reflective masks, whose defect inspection is even more challenging), to the chemical formulations of photoresists (needing to adapt to new wavelengths with high sensitivity and resolution), to metrology and inspection equipment (how to measure overlay accuracy at the atomic scale), and finally to wafer fabrication, packaging, and testing… what we need is a complete, autonomous, highly collaborative technology ecosystem." The footage showed various domestic partner companies and research institutes overcoming difficulties, successes and failures alike. Xiuxiu emphasized repeatedly, "Without this ecosystem, the lithography machine is nothing but an expensive island."
The footage on the circular screen gradually dimmed, finally settling into a deep blue, like the night sky at the beginning. The lights in the hall came back on, yet the silence remained, as if everyone was still immersed in the decade‑long technological odyssey.
Xiuxiu stepped forward a few paces, to the very edge of the stage. She looked out at the audience, her gaze profound, as if it could pierce through time to those days and nights of struggle, the comrades who fought alongside her, the families who gave support and understanding, and the two people who held special places in her life and career—even if they were not present at that moment, she could feel their intangible support.
She drew a slight breath, and her voice, deeper than before, carried a power that stirred the soul.
"What you just saw is not only the journey of one enterprise, nor merely a microcosm of the development of China's lithography technology." She paused, letting each word land clearly in the ears of the audience. "This is the collective wisdom of human collaboration, a heartfelt declaration to the limits of physical law."
"The mountain we have been climbing is not a peak of market share, but a technological summit built from knowledge, sweat, resilience, and the courage to stand up again after countless failures. What we have been fighting is not just technological barriers and international competition, but the boundaries of human cognition and the limits of engineering capability itself."
"This lithography machine, now standing at the pinnacle of the world—every component, every line of code, every optimization of parameters—embodies the wisdom and dedication of countless individuals. It is the collective work of mathematicians, physicists, chemists, engineers, technicians… of tens of thousands of unsung strivers, who used their youth and talent to co‑author this answer to the world."
Her voice trembled slightly, but quickly steadied, her eyes growing brighter and more resolute.
"This answer does more than just show how to manufacture the most precise machine. It answers this: when humanity faces seemingly insurmountable obstacles, does it choose to retreat or to forge ahead? When knowledge is restricted and technology is blocked, does it choose dependency or self‑reliance? And it answers an even deeper question: in the face of the vast universe and the cold, indifferent laws of physics, what enables us—this tiny existence—to leave our mark?"
"The answer is: collaboration, exploration, and an unquenchable thirst for truth and a better future. We use light to converse with matter; we use code to define logic; through the small efforts of countless individuals, we converge into a mighty current that advances civilization. This is what we should truly celebrate tonight."
She looked out once more, her gaze sweeping across every moved face in the audience.
"So today, the title of this answer we present is not 'Number One in the World,' but 'We Made It.' This honor belongs to every person who has contributed to this dream over the past decade and more. And it belongs to all those who believe in science, in innovation, and in the power of human cooperation."
"The road ahead is still long; there are more limits to physical law waiting to be challenged—BEUV with even shorter wavelengths, revolutionary quantum lithography, atomically precise manufacturing… But tonight, let us pause for a moment, to celebrate the road we have traveled, the light we have ignited."
Xiuxiu bowed slightly.
"Thank you."
No rousing call to action, no excessive portrayal of the future. She had simply recounted a history, shared a reflection. But after a brief silence, the hall erupted in thunderous, sustained applause. The applause was not just for commercial success, but for a tangible epic of human intelligence and perseverance, for a profound inquiry into the essence of technology and the human spirit. Xiuxiu stood in the center of that applause, her figure somewhat slender under the spotlight, yet as if bearing the weight of the entire cosmos. She knew: this answer had been etched into the annals of the era.