I started with a ship full of max-level veterans, and I'm just a complete noob.

Wang Shouwu put the thin-covered notebook back into his jacket pocket, and that afternoon he followed the 502 technical team into the Third Electronics Factory. The security personnel checked his temporary pass before letting him through.

He walked into the 502 research room and first saw the Yuanlei No. 1 permanent magnet assembly on the corner iron frame, next to which were disassembled waveguide and pulse modulator parts.

A cross-sectional diagram of a magnetron and a circuit diagram of a double-balanced mixer are displayed on the wall. Vacuum tubes, high-frequency connectors, and resistors awaiting selection are laid out on the long workbench.

The simple single crystal furnace stands in the inner position, and the modified vacuum evaporation furnace body is connected to the lifting frame. The recording pen on the control panel has been pressed down on the starting point of the paper tape.

Most of the equipment in this lab is related to electron tubes and microwaves, but the graphite crucible below the furnace opening contains purified germanium material needed for the third crystal pulling process.

Old Sun has already disassembled and inspected the worm gear, smoothed out all the burrs on the tooth roots, and remeasured the thickness of the thin shims on the drive shaft.

The idling test was conducted at 28 and 35 revolutions per minute for 15 minutes each. Fang Xudong recorded the speed fluctuations, axial movement, and motor temperature rise on the back of the process card.

"In actual operation, it is only turned on at 28 RPM. The speed controller is mechanically limited at 35 RPM, and it cannot be turned up any further."

Old Sun turned the speed control knob to Wang Shouwu to see that the limit screw had been tightened and the lead seal wire went through the screw to the side panel of the control panel.

After checking the records, Jiang Ming fixed the lifting speed at 0.8 millimeters per minute and then asked Da Liu to merge the grid voltage record into the time axis of the temperature control paper tape.

The charging tray is sent to the furnace side, and the polycrystalline germanium with the enriched tail end is cut off and put into the graphite crucible piece by piece, with the weight being consistent with the second furnace.

After the furnace lid is closed, argon gas enters the furnace cavity according to the process card. The pressure and flow rate stabilize within the specified range, and the heating circuit begins to increase the induction power.

Wang Shouwu stood between the control panel and the viewing window, his gaze shifting from the temperature paper strip to the surface of the liquid in the crucible, a black pen clipped to the cover of his notebook.

As the germanium block softened at its edges, the silvery-gray melt spread out from the bottom of the crucible. After the last solid piece sank to the surface, Jiang Ming kept the power at the current setting.

As the melt temperature approached 945 degrees Celsius, Fang Xudong calibrated the pyrometer reading, while Lao Sun turned the lifting handwheel to bring the seed crystal tip closer to the liquid surface.

When the brightness at the contact point changes, the melt adheres upwards along the seed crystal, and the meniscus gradually forms while the edges remain smooth.

"Contact is stable, rotating mechanism ready."

Old Sun turned off the motor switch, and the seed crystal went from a standstill to a low speed, then rose to 28 revolutions per minute, and shallow and continuous vortex patterns appeared on the surface of the melt.

Fang Xudong pressed close to the viewing window, examining the solid-liquid interface along both sides of the crescent moon, and wrote "complete shape" in the first column of the recording paper with his pencil.

"The crescent is stable, with no visible polygonal edges, and the temperature is 944.9 degrees Celsius."

"Begin lifting, at a rate of 0.8 millimeters per minute."

The transmission mechanism carries the seed crystal upwards at a constant speed. After the meniscus is stretched, it stabilizes again, and the metallic gray crystal gradually grows out from above the melt.

At five minutes, Fang Xudong recorded the crystal diameter and meniscus width, and wrote the tachometer reading next to the temperature data.

Ten minutes later, the length of the crystal was nearly eight millimeters, the side of the crystal maintained a continuous luster, and the growth lines were evenly distributed circumferentially.

Wang Shouwu put his hands in the pockets of his Zhongshan suit and stood to the side of the viewing window to observe whether the swirling patterns would hit the crucible wall and reflect back.

At 20 minutes, the crystal length approached 16 millimeters, and the diameter change caused by the drop in the melt level was gradually corrected by the control loop.

"Stable at 28 revolutions, gear cycle recording is normal, axial position is consistent with paper tape."

Old Sun's palm was pressed against the outer shell of the transmission box, and the worm gear and worm remained continuously engaged. The intermittent jamming that had occurred in the second furnace did not reappear.

Fang Xudong marked the interface shape every five minutes. The circular marks on the record paper remained intact, and no broken line symbols representing ridges appeared.

At the thirty-fifth minute, the pointer on the voltmeter next to the control panel shifted one notch to the left, and the heating power decreased by about 0.5 percent due to fluctuations in the power grid.

As the melt temperature decreased, the meniscus contracted towards the center of the crystal. Fang Xudong immediately marked the contraction position next to the scale on the viewing window.

Da Liu's hand was already on the manual voltage regulator switch. Jiang Ming looked at the recovery curve drawn by the recording pen and temporarily let the automatic loop continue to work.

After the controller replenishes the power, the temperature curve quickly returns to the set range, and the meniscus contraction is controlled within 0.3 millimeters.

"The interface remains intact; continue scrolling."

Wang Shouwu glanced at the paper tape; the pen tip had returned to its original narrow fluctuation range. He then focused his attention back on the solid-liquid interface.

Forty minutes later, the crystal length exceeded thirty-two millimeters, the metallic gray sides remained smooth, and the diameter change was within the expected range.

By the fiftieth minute, the remaining melt in the crucible had dropped to the stop line. Jiang Ming signaled to Lao Sun to stop the ascent, while maintaining the rotation to allow the crystal to detach from the liquid surface.

The meniscus gradually narrows and finally breaks off from the end of the crystal. The lifting mechanism then raises the entire crystal to the cooling position below the furnace opening.

Once the temperature dropped to a workable range, Lao Sun put on heat-resistant gloves, took out the crystal, placed it in a cork clamp, and measured its total length, which was close to forty millimeters.

The crystal surface is intact, and the luster on the side extends from the head to the tail. Only a shallow growth line is left at the location corresponding to the power grid disturbance.

Old Sun fixed the crystal on the cutting table and used a diamond wire saw to cut a one-millimeter-thick slice from the tail. The saw wire passed steadily along the positioning groove.

Fang Xudong took the thin slice and completed the rough grinding and polishing in sequence, then clamped the sample into the stage of the polarizing microscope.

The changes in brightness and darkness in the field of view unfold continuously in the same direction. After rotating the stage, the brightness of the entire area changes synchronously, and the orientation remains consistent throughout.

"The tail section has the same orientation, and the third batch is still a single crystal."

He gave the microscope to Wang Shouwu, who examined the entire edge and then personally rotated the stage to check it before returning to the measuring table.

The four-probe measurement then begins, with the crystal head fixed at the starting point of the fixture, and the probes falling sequentially at intervals of two millimeters.

Fang Xudong controlled the current, Lin Lanying read the voltage, Jiang Ming marked the converted resistivity on graph paper, and Wang Shouwu stood on the other side to check it simultaneously.

The data in the first few sets of the head remained at a high level, and gradually decreased after entering the middle section. The slope of the curve slowed down significantly compared to the second single crystal.

After the measuring point exceeds 30 millimeters, the resistivity at the tail continues to decrease, but the previous rapid descent has narrowed.

The last set of readings was written into the table. Fang Xudong recalculated the average value of the head and the average value of the tail, and then pushed the calculation paper in front of Jiang Ming.

"The difference between the beginning and the end is 16%."

Jiang Ming marked the 14% predicted last night next to the measured curve. The two curves basically overlapped, but there was still a deviation of about two percentage points at the tail end.

After increasing the revolutions per minute from twelve to twenty-eight, the difference in resistivity between the beginning and end was reduced from 30% to 16%, and the direction and magnitude of the change given by the rotating boundary layer model were supported by physical evidence.

Wang Shouwu bent down to look at the graph paper, his pen moving along the measured curve from the beginning to the end, finally stopping at the deviation below the theoretical line.

Jiang Ming retrieved the crucible usage record and placed the three melt holding times, charge weights, and graphite inner wall contact areas next to the curve.

"The remaining two percentage points should be mainly due to carbon impurities contributed by the graphite crucible. The next step is to treat the crucible itself."

He used a pencil to list two feasible paths on the record sheet.

"The graphite crucible can be densified to reduce the release of impurities during high-temperature contact, or a high-purity quartz crucible can be used, and then the tail-end deviations of the same batch of germanium materials can be compared."

After listening, Wang Shouwu remained silent for a moment, then took out the thin leather notebook, which was already filled with many pages, from the pocket of his Zhongshan suit.

He turned to the blank page, first noting down the third furnace, twenty-eight revolutions, and sixteen percent, then added a line below.

The notebook was facing his chest, and Jiang Ming could only see the pen pause briefly at the end of a line, while the bottom line was still hidden by his palm.

"Compile this week's records and I'll take them back to the office to review them."

Wang Shouwu closed his notebook and put the measured curves and calculations into his briefcase.

As I left the furnace, the temperature control paper tape was still moving slowly forward, and the recording pen had long since passed the narrow peak left by the power grid disturbance.