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

Jiang Ming twirled the chalk between his fingers, using the rough end to erase a blank space between the three band diagrams in the center of the blackboard.

With the scratching sound of chalk across the blackboard, two parallel vertical lines appeared, with the germanium route and silicon route written at the top respectively.

"Not only are they all retained, but they also provide a very solid foundation." Jiang Ming's voice was calm and resolute, firmly supporting Wang Shouwu's question hanging on the table.

He exerted force with his wrist, writing "regional purification" on the left column and marking "six rounds of zone melting," "three nines of purity," and "plus or minus 0.09 degrees Celsius temperature control" on the right. Then he moved the same process to below the silicon route.

"The melting point, impurity diffusion coefficient, melt viscosity and density of silicon need to be remeasured. The physical relationship used in the segregation process still holds true. Only the material parameters need to be replaced."

Jiang Ming wrote the effective segregation coefficient of BPS in the middle of the two columns, with an arrow connecting germanium to silicon. Wang Shouwu raised his hand to straighten his gold-rimmed glasses, his gaze following the arrow to the formula.

He was familiar with the theory of segregation and could naturally see that the formula described the transport of impurities at the interface front, and the specific material was only included in the calculation through diffusion coefficient, viscosity, density and equilibrium segregation coefficient.

Over the past few months, 502 first controlled the melting zone on the germanium rod, then increased the revolution from 12 to 28, and even eliminated the deviations caused by carbon precipitation in the graphite crucible. These practical furnace experiences cannot be directly replaced by a paper.

Jiang Ming continued writing down the single crystal growth, marking the rotating disk boundary layer, the 28-turn process window, and the 9% difference in resistivity between the head and tail next to the germanium route, while leaving two conditions for recalculating the rotation speed and thermal field next to the silicon route.

"After the seed crystal rotates, radial flow and axial replenishment still exist near the solid-liquid interface, and the boundary layer thickness is still determined by the rotation speed, kinematic viscosity and diffusion coefficient."

Wang Shouwu opened the thin-covered notebook and found the sketch of the rotating disk that Jiang Ming had drawn before. The lines that originally belonged only to germanium single crystals now extended along the same structure to the silicon melt.

The resistance he felt to being forced to abandon the old path gradually eased, but the 1420-degree angle still loomed in his way. Physical relationships could be transferred, but the equipment needed a complete overhaul.

The third item is crystal orientation control. Jiang Ming wrote "back reflection Laue orientation, deflection angle correction of 3.8 degrees, device dispersion of 6%" in the left column. He only wrote four words next to the silicon route, which can be directly applied.

"X-rays diffract in the crystal lattice to determine the orientation of the crystal plane. For germanium and silicon crystals, only the lattice constant and film index table need to be changed, and the equipment, turntable and cutting process can continue to be used."

Fang Xudong looked at the book of Laue negatives on the table. It contained a complete record of overexposure, large spacing, clear spots, and step-by-step corrections. He had personally developed each negative and understood the weight behind the words "directly applicable".

The old medical X-ray tubes that were originally built to solve the problem of 3.8-degree deviation have now been transformed from temporary emergency equipment into a ready-made starting point for the silicon single crystal orientation process.

On the fourth line, Jiang Ming wrote "closed-loop temperature control". The germanium route was marked as 937 degrees, ±0.08 degrees, dual platinum resistance differential measurement and PID control, while the silicon route was marked as 1420 degrees, high temperature sensor, new heating element and parameter resetting.

"After the temperature zone is moved up, the characteristics of the heating element, the thermocouple output, the thermal inertia of the furnace body and the control parameters all need to be redone, but the step response, time constant determination, integral anti-saturation and differential filtering can still use the original methods."

Wang Shouwu's gaze lingered on the temperature control precision line for a long time. 1420 degrees would force out existing quartz tube, platinum resistance and molybdenum wire heating elements, but the control method established by 502 had already undergone actual furnace testing with load changes, protective airflow and thermal inertia series.

He was initially worried that switching to silicon would mean reorganizing a team and figuring out the process from mineral purification to device packaging, but the two columns of processes on the blackboard were dispelling his concerns one by one.

Jiang Ming wrote the last line: Surface treatment and device processing. The left column is pickling, vacuum annealing, silicon oxide encapsulation, and double-diffused germanium NPN transistors. The right column is silicon thermal oxidation, diffusion windows, and high-frequency devices.

There was no room left in the center of the blackboard, so he put the chalk back in the slot and turned to look at Wang Shouwu.

"You asked if all this work was in vain. My answer is clear: every process step that has been verified on germanium is the first step that has been completed on the silicon route."

Wang Shouwu was still looking at the two columns of procedures. Jiang Ming waited until he had finished reading each item before reaching out and pointing to the top of the right column.

"We'll start with 70% completion."

The sound of pages turning in the conference room resumed. Lin Lanying pulled the silicon property table to the top, while Huang Kun checked the existing equipment and material channels line by line along the two process columns.

Xie Xide brought the two sets of photoconductivity spectra in front of him. The defect peaks of the germanium sample after mechanical polishing occupied most of the image, while the peaks in the middle of the band gap of the silicon sample had been reduced after oxidation treatment.

"The interface aspect is even more advantageous when it is migrated to silicon, as the interface state density between silicon and silicon oxide is usually one to two orders of magnitude lower than that between germanium and germanium oxide."

She placed the pencil in the same measurement range of the two curves, allowing Wang Shouwu and Huang Kun to directly observe the difference.

"After the interface leakage current decreases, the minority carrier lifetime, junction stability and operating temperature will improve, and the increase in high-frequency cutoff frequency will also benefit from the overall interface quality."

As Jiang Ming listened to this supplementary information, the last bit of anxiety in his heart finally subsided. He had previously been able to deduce the bandgap advantage of silicon from publicly available materials, while Xie Xide's reference spectral lines provided experimental evidence for the interface route.

Huang Kun flipped back to the line below the record book, and wrote three words on the paper with his pen: "Agreed to transfer."

After he finished writing, he did not close the notebook. Instead, he listed alumina tubes, silicon carbide heating rods, and tungsten-rhenium thermocouples, and marked the compatible units after each item.

"The renovation of Furnace No. 3 involves three supply channels. Alumina tubes can be obtained from the institute's high-temperature experimental group, silicon carbide rods need to be obtained from the ceramics factory, and tungsten-rhenium thermocouples can be borrowed from existing projects. The furnace schedule also needs to be rearranged."

Huang Kun looked up at Jiang Ming, his pen still stuck on the "renovation cycle" column.

"How long will it take you from dismantling the furnace?"

Jiang Ming unfolded the structural diagram of Furnace No. 3 and estimated its structure according to four parts: furnace tubes, heating element, temperature measurement circuit and controller. He was unwilling to compress the cycle in order to secure project approval, as that would only leave the risks to be exposed during the first silicon melting.

"Mechanical structure modification will take about two weeks, temperature control readjustment will take about one week, and no-load verification and test run with materials will require some margin. The whole cycle is prepared in four to five weeks."

Huang Kun wrote down five weeks after the cycle, and had already begun to adjust the project order of Furnace No. 3 in his mind. Silicon conversion is worth investing resources in, but other tasks in the institute will not give way to this route on their own.

Wang Shouwu finally shifted his gaze from the blackboard back to his notebook, and wrote a line below the original question mark: "From germanium to silicon, a turning point in the technological route."

He placed the line of text on a horizontal line, stopped writing, and asked, "When did you come up with this idea?"

"The night the frequency data for the first batch of 27 tubes came out."

Wang Shouwu's lips moved, his fingers turned the page of the record, and he looked at the five sources of error again. At that time, he still wanted to use six nine-germanium materials, temperature increase and time reduction and narrow base region to continue to push upward, but Jiang Ming had already put the material boundary into the next round of verification.

That restraint stirred up a complex feeling in his heart. If Jiang Ming had declared on the spot that the germanium route had come to an end, he would probably have used more process data to refute it. Now, the data from both sides just happened to push the conclusion to the same point.

Wang Shouwu closed his notebook and looked up to stare directly at Jiang Ming.

"you are right."

These words made Wu Hanzhang loosen his grip on the preliminary research plan. Wang Shouwu had always only believed in experiments and formulas, and this acknowledgment meant that the semiconductor research group had officially accepted the material route shift.

In the remaining twenty minutes, the four parties wrote down their preliminary division of labor in the meeting minutes.

The Institute of Physics was responsible for the furnace time of Furnace No. 3 and the alumina tube channels, the Semiconductor Research Group provided tungsten-rhenium thermocouples and the first batch of silicon material, and 502 was responsible for the temperature control modification and heating element replacement.

Xie Xide took over the silicon surface state comparison measurement and required that subsequent samples follow the joint numbering rule so that each spectral line could be traced back to the cutting, cleaning, oxidation and annealing conditions.

Huang Kun added a line to the margin of the minutes: After the alumina tubes arrive at the warehouse, their dimensions must be checked and they must be pre-fired before they can be loaded into the furnace.

Jiang Ming signed his name on the last page and put the No. 3 furnace structure diagram and modification list into a canvas bag.

The materials from the meeting were finalized, and the five-week renovation cycle began from this moment.

The first items sent to the inspection rack the next day were three high-purity alumina tubes transferred from the Institute of Physics' warehouse.