Siheyuan (traditional courtyard house): Starting with the Korean War, returning home to take charge

The task force hit a wall in the third month.

He Yuzhu stood outside the cleanroom, peering through the glass. A label reading "45nm Experimental Prototype" was affixed to the silver-white machine's casing, a corner of the red lettering chipped off. He didn't go in; he just stood there, able to feel the low air pressure inside. Several technicians squatted in front of the machine, no one speaking, only the machine's cooling fans humming.

Factory Director Zhou came out clutching the test report, a corner of the paper dampened by the sweat from his palms. He didn't hand it over; instead, he sighed, his voice choked with embarrassment.

"He Chuchang failed the first six times."

He Yuzhu took the report and turned to the page with the sixth test. Exposure uniformity: deviation of 15%. Line width: 45 nanometers ± 5 nanometers. Pass rate: less than 30%. He closed the report without saying a word.

"The lens is warped by heat, resulting in insufficient exposure accuracy. The line width is uncontrollable, some lines are too wide, some are too narrow, there are short circuits, open circuits, a whole host of problems," said Director Zhou, gesturing with his hand. "It gets hot when running, and when it gets hot, it becomes crooked."

He Yuzhu returned the report to him. "Where are Director Qian's materials?"

Factory Director Zhou turned to another page, tapped the data with his finger, and moved his lips but didn't immediately speak. "The new material has a 20% better light transmittance, but it..." He paused, as if choosing his words carefully, "...expands when the power is high. If the power is low, the exposure time is too long; it takes half a day to expose a single silicon wafer, making it less efficient than the old machine."

He Yuzhu didn't reply. He pushed open the workshop door and went inside. The machines were still humming, and the indicator lights were flashing. He squatted down, reached out and touched the outer casing next to the lens mount. It was hot; he could feel the heat seeping out when he placed his palm against it.

Researcher Wang from the Institute of Microelectronics, Chinese Academy of Sciences, was squatting in front of the control panel, holding a notebook and taking notes. When he saw He Yuzhu, he stood up and took off his reading glasses.

"The problem isn't with the materials. Lens thermal distortion is a structural issue. Uneven heat dissipation, with one side hot and the other cold, will cause the lens to warp."

He Yuzhu stood up. "Can it be changed?"

Researcher Wang didn't answer directly. He put on his reading glasses, then took them off again, and wiped the lenses with the corner of his shirt. "Improve the heat dissipation structure, add cooling channels, and let the coolant flow evenly around the lens. With a more stable temperature, distortion will be reduced."

He Yuzhu turned around and looked at Factory Director Zhou. "How long will it take to make the changes?"

Factory Director Zhou thought for a moment, then looked at Researcher Wang. "Two weeks. Redesign the cooling system, machine the parts, and install and debug."

He Yuzhu nodded. "Revise it. Try it again after you're done."

The seventh test run was scheduled for an afternoon two weeks later.

He Yuzhu went to Shanghai again. The workshop was packed with people: technicians from the Shanghai Radio Factory, researchers from the Institute of Microelectronics of the Chinese Academy of Sciences, and young people sent by Qian Zhiyuan from the Institute of Materials Science, filling the cleanroom to capacity. The air conditioning was on full blast, but He Yuzhu still felt stuffy. Standing at the back of the crowd, he could see the "45nm Experimental Prototype" label on the machine, the red lettering completely blurred.

Factory Director Zhou stood at the control panel, his hand on the start button, but he didn't press it. He glanced back at He Yuzhu, then turned back to the screen, staring at the fluctuating temperature data. After about ten seconds, the temperature stabilized.

"Temperatures are normal everywhere, plus or minus 0.5 degrees Celsius," the operator reported.

Factory Director Zhou took a deep breath and pressed the button.

The machine started. The light source shone brightly, blinding everyone. The lens rotated, the workpiece stage moved, and the silicon wafer slowly moved under the exposure lamp. The workshop was quiet, with only the hum of the machines. He Yuzhu stared at the numbers on the instrument panel: pressure, temperature, vacuum—all within the normal range. But he noticed that Factory Director Zhou's hand never left the red emergency stop button; his finger rested on it, but he didn't press it.

Thirty minutes. Forty minutes. Fifty minutes.

The machine stopped.

The technician removed the silicon wafer and placed it under a microscope. Researcher Wang leaned in and stared at it for a long time, motionless. No one spoke in the workshop, except for one person who swallowed loudly.

Factory Director Zhou couldn't hold back any longer. "Old Wang?"

Researcher Wang didn't turn around. He looked for another ten seconds or so before straightening up. He took off his reading glasses, and without saying a word, he exhaled.

Linewidth: 45 nanometers, ±0.5%. Uniformity: 3% deviation.

He paused, put his reading glasses back on, glanced at the microscope again, and then added a sentence.

"Pass rate: 95%"

There was a moment of silence in the workshop. Not a deathly silence, but a long-suppressed, unbelievable silence. Then someone in the corner chuckled softly, like a sigh of relief. Next, someone slapped their thigh, someone squatted down, someone closed their notebook, and let out a sigh of relief.

Factory Director Zhou stood in front of the control panel, his finger still pressed on the emergency stop button, his knuckles white. He paused for two seconds, then withdrew his hand and wiped the sweat from his palms on his trousers.

"It's done," he said.

The sound wasn't loud, but everyone in the workshop heard it.

He Yuzhu stood at the back of the crowd, motionless. He watched the technicians squatting on the ground, heads in their hands, watched Researcher Wang take off his reading glasses and put them back on, watched Factory Director Zhou standing motionless in front of the control panel. He didn't say anything, turned around and walked out of the workshop.

It was getting dark outside; the streetlights had just come on, casting a dim yellow light on the factory's concrete road. He stood at the entrance, took a cigarette from his pocket, lit it, and took a drag. The smoke dissipated quickly in the wind.

That night, He Yuzhu stayed at the factory's guesthouse. He sat on the bed, took the list out of the system space, turned to the page for "lithography machine," and added a line after the words "45 nanometers": Shanghai Radio Factory, Institute of Microelectronics of the Chinese Academy of Sciences, and Qian Zhiyuan Institute of Materials Science jointly tackled the problem, and the seventh test run was successful, with a linewidth of 45 nanometers ± 0.5 nanometers and a pass rate of 95%.

Once you're done writing, put the list back and lock it.

The next morning, He Yuzhu went to Qian Zhiyuan's research institute. Qian Zhiyuan was in the laboratory, squatting in front of a microscope, examining a slice of material. He heard the door open, looked up, and took off his reading glasses.

"Xiao He, did it work?"

He Yuzhu sat down opposite him. "It's done. Your materials have served their purpose."

Qian Zhiyuan didn't laugh. He stood up, walked to the cabinet, took out a piece of silvery-white metal, and handed it to He Yuzhu. He Yuzhu took it; it was heavy, smooth, and gleamed coldly under the light.

"This is a new formula. The coefficient of thermal expansion is 30% lower than the previous version, and the light transmittance is increased by 10%. When used in the next generation of lithography machines, it can produce finer linewidths."

He Yuzhu weighed the piece of metal in his hand. "Thirty-two nanometers?"

Qian Zhiyuan nodded. "Theoretically, yes. But it needs to be tested. It needs people, equipment, and time."

He Yuzhu returned the metal to him. "Personnel will be transferred from various departments. Equipment will be purchased from abroad. Timeframe: five years. In five years, I want to see a 32-nanometer lithography machine."

Qian Zhiyuan put the metal back in the cabinet and closed the door. "Okay. I'll take care of it."

He Yuzhu stood up and extended his hand. Qian Zhiyuan grasped it and shook it.

"Director Qian, please take care."

"The same to you."

Back in Beijing, it was already dark. He Yuzhu had just entered his office when the phone on his desk rang. He answered it, and there was a lot of noise on the other end—someone was shouting "Increase the pressure!", someone was reading data, and then Lin Jianguo's voice came through. It wasn't shouting, but a strained, panting voice, like someone who had just run a long-distance race.

"Dean, the chips have arrived."

He Yuzhu didn't say anything.

There was a pause on the other end of the phone, followed by the soft, steady sound of something being placed on a table.

"The linewidth is ±0.3, even better than the design specifications. Dean, Galaxy VI... it's up and running."

He Yuzhu held the microphone and heard someone crying on the other end.