Volume 1: Student Life Chapter 256: Bringing Another Person into the Gang
After Zhang Yifan left, Chen Zhou went to the bathroom to take a shower.
He was not planning to sleep, but just wanted to review the contents of the entire preparation process so that he could fall asleep easily.
Chen Zhou will further sort out the information sent by Zhang Yifan and Shen Jing.
On the one hand, take the essence of the essence.
On the one hand, verify your research ideas.
Originally, Chen Zhou planned to gain a comprehensive understanding of all the preparation processes of diamond films.
Take the advantages of various processes and try to combine and optimize them.
However, this method is too difficult.
There was no way he could do it in a short period of time.
Take his very first idea, which was to combine the quality of diamond films prepared by the MPCVD method with the speed of the DAPCVD method.
It seems beautiful, but there are endless problems.
If time is not a limitation, Chen Zhou would be willing to do more research.
But now, he decided to put this idea aside for now.
Simply starting from the improvement of MPCVD method.
If there is a chance in the future, I will try to combine the two organically.
After taking a shower, Chen Zhou looked at the time. It was not yet three o'clock.
He thought about it and set the alarm for 3:30.
More than half an hour was enough for him to sort out all the information.
What he needs now is data reference and evidence.
Although each laboratory's equipment, devices, preparation parameters and other conditions are different.
However, these are not problems in the face of the powerful .
On the contrary, it is of great reference value.
When the alarm rang, Chen Zhou just stopped writing.
He smiled slightly, and as expected, his timing was just perfect.
After saving the data on the computer and organizing , Chen Zhou climbed into bed and went to sleep.
The next day, Chen Zhou got up at 7:30 in the morning.
Although he only slept for four hours, Chen Zhou's mental state was extremely good.
After getting out of bed and washing up briefly, Chen Zhou went to the hotel restaurant for breakfast.
So I went back to the room and hung a do not disturb sign on the door.
Today, he is devoting himself to the research of improving the preparation process.
However, just as Chen Zhou turned on the computer, he heard a knock on the door.
Frowning slightly, Chen Zhou stood up and opened the door.
Standing outside the door was Zhang Yifan.
Seeing Zhang Yifan, Chen Zhou immediately understood. He smiled and asked, "Why don't you sleep a little longer?"
"I can't sleep..." Zhang Yifan hesitated for a moment, and finally said, "I also participated in a project taught by the teacher once, but it was not as intense as yours. How should I put it? It was very fulfilling and exciting..."
Chen Zhou joked: "You mean nervous and exciting?"
Zhang Yifan: "Uh... almost..."
Chen Zhou glanced at Zhang Yifan and asked, "Are you sure you don't want to take a break?"
Zhang Yifan shook his head: "I really can't sleep..."
"Okay," Chen Zhou let Zhang Yifan into the room, "Then help me build an analysis model."
Zhang Yifan was stunned and asked weakly, "What analysis model?"
Chen Zhou saw Zhang Yifan's hand opening the computer and paused for a moment. He immediately smiled and said, "Don't worry, the analysis model of the diamond film preparation process is very simple."
As he spoke, Chen Zhou walked back to his computer and handed yesterday's research results to Zhang Yifan.
Then, he gave Zhang Yifan another contact number.
Zhang Yifan asked curiously: "Who is this person?"
Chen Zhou replied: "A senior from the Computer Science Department of Yanda University, you two should work on this analysis model together."
Zhang Yifan said "oh" and then added the other party's contact information.
Only then did he realize that Chen Zhou had unknowingly pulled in another person.
This person is none other than the third person in the official UPC competition, Fang Jieming.
Originally, Chen Zhou was just trying it out to see if the other party was willing to help.
But what Chen Zhou didn't expect was that Fang Jieming agreed very readily.
In addition to being surprised, Chen Zhou thanked him repeatedly and mentioned the idea of playing together.
However, Fang Jieming quickly said that he had quit.
I haven't played since the last UPC ended...
After Zhang Yifan and Fang Jieming contacted each other, they began to build the analysis model.
This is a very simple model, and according to the two people's estimate, it can be completed in more than two hours.
Chen Zhou also opened the information he had sorted out before going to bed last night.
Based on the trial and error ability of the wrong question collection, the parameters of the preparation process are constantly adjusted.
"During the preparation of diamond, at high methane concentrations, there will be a large amount of carbon-hydrogen precursors on the substrate surface, with low mobility and high supersaturation of carbon-hydrogen precursors on the steps."
"During the migration process, the carbon-hydrogen precursors on the steps are very likely to agglomerate with other carbon-hydrogen precursors and form nuclei."
"At the same time, at locations where there is no or little migration, the carbon-hydrogen precursors are incorporated into the crystal."
"So, as the methane concentration increases, you end up with an irregular growth morphology."
Chen Zhou thought about this and wrote on the draft paper:
[When the methane flow rate is low and the diffusion length of the hydrocarbon precursor is greater than the width of the step, the supersaturation of the adsorbed species on the step will be lower than the critical value required for nucleation. ]
[In this case, the carbon-hydrogen precursor that reaches the terrace will diffuse to another step, thus forming laminar growth. Laminar growth can produce a single epitaxial surface result, which is suitable for the preparation of single crystal diamond. ]
[Therefore, under the premise that the substrate has been selected, appropriately reducing the methane concentration can effectively inhibit irregular growth, promote laminar growth, and increase the growth time and thickness of higher-quality diamond epitaxy. ]
After writing this paragraph, Chen Zhou looked back again and wrote a range next to it.
【2%～9%】
This is the wrong range for the initially proposed methane volume fraction.
Using the same idea and method, Chen Zhou determined the trial-and-error range of working pressure, microwave power and substrate temperature.
However, it still takes time to find the most suitable parameters in this range.
Just as Chen Zhou thought before, the preparation process of diamond is itself a contradictory issue.
Its production rate will increase with the increase of methane concentration, working pressure and substrate temperature, but too high methane concentration and substrate temperature will reduce the quality of diamond.
At 11 o'clock in the morning, Zhang Yifan and Fang Jieming completed the construction of the analysis model.
Chen Zhou casually handed over a data parameter obtained through trial and error through a set of wrong questions to the two people, and asked them to further analyze it through the analysis model.
The analytical model can preliminarily obtain theoretical results for the current data parameters, which can be regarded as a further verification of the trial and error of the right and wrong question set.
Based on this feedback information, Chen Zhou adjusted the trial and error interval and verified it again using the wrong question collection.
Afterwards, the data was handed over to Zhang Yifan and Fang Jieming.
In this way, the cooperation between the three became more and more tacit.
Improvements in diamond preparation technology are also achieving the desired goals.
At one o'clock in the afternoon, after a short rest, Chen Zhou and his two companions resumed their follow-up work.
Chen Zhou had a hunch that he should be able to figure it out today.
