Chapter 458: Linear Array is in the works

Speaking of this matter, Lin Lianwei was even more excited than Gao Zhendong.

This means that the circuit design of their orthogonal four-element detector will be much simpler. Although very good consistency is not required, better consistency is beneficial to the performance of the seeker.

They have calculated that if a crystal is cut into pieces, with a size of a mercury cadmium telluride crystal of a few millimeters thick and more than ten millimeters long, at least one set of four infrared photodiodes can be made. They are a natural match, so there is no need to worry too much about compensation and balance in the circuit.

Engineer Lu also applauded. Now, the most core thing of the Thunder-1 modification, the orthogonal four-element infrared detector, has been completely solved, and the solution has been done very well.

He looked at Gao Zhendong and said, "Boss Gao, you make the announcement. I see the comrades over there are getting impatient. Haha."

Gao Zhendong shook his head: "You guys made this, you guys announced it yourself, I'm too lazy to tell you, haha."

Mercury cadmium telluride crystal is not equal to mercury cadmium telluride infrared photodiode. Gao Zhendong was too lazy to even grab the glorious moment when his comrades announced their success.

Lu Gong had dealt with Gao Zhendong more than once or twice, and he probably knew a little about Gao Zhendong's character, so he didn't hesitate: "Okay, then I won't waste my time."

After saying that, he raised his head and announced loudly to the crowd at Factory 1274: "Comrades! This pipe is done! It's a success! Thank you for the strong support from the comrades at Factory 1274!"

As soon as he finished speaking, although he did not reveal even a word about the specific performance, all the comrades cheered together.

For the comrades of Factory 1274, including Fang Yinghong and others who came from the Third Rolling Mill for support, this at least proves that the improvement of the diffusion furnace is effective. It may not cover the needs of integrated circuits, but at least for now, it can meet the process requirements of some new products.

This in itself is of great significance.

The comrades in charge of testing at the Institute of Guidance and Research were now able to applaud. They were actually the first group to know the performance of the infrared photodiode, but they could not tell it in advance. They could only watch the excellent performance of the device while trying their best to suppress their surging desire to express themselves, until Engineer Lu officially announced the success.

When everyone was almost happy, Gao Zhendong said with a smile: "Comrades, today, I came to visit you, solve some problems, and treat you to a good meal. But now it seems that I can save money on this meal. I'm afraid that the comrades from the Institute of Directed Research will have to treat us to this meal."

He can't treat the dinner to be his own, the Institute of Research and Development has to come forward. He can't say that he is the deputy chief designer of the Thunder-1 modification, and without this identity, he can't take care of this matter himself.

Everyone burst into laughter. Mr. Gao had thought of everything, even planning for meals.

Engineer Lu laughed out loud after hearing what he said. "Yes, yes, yes, what Mr. Gao said is right. No one should compete with us for this meal today! We should really thank the comrades from Factory 1274 and the Third Steel Rolling Mill for their hard work and cooperation in order to provide us with new components."

For him, this dinner had to be treated. Factory 1274 did a good job of cooperation. In addition to official thanks, these things were also necessary. Otherwise, he would appear to be a bad person.

Besides, the deputy chief engineer is here. It was he who asked the Research Institute to treat him to a meal. He is not afraid that the bill will not be paid. It is equivalent to General Gao approving the funds to give them face.

When they heard that there was really food to eat, the comrades from Factory 1274 were delighted, and the comrades from the Research Institute were very open-minded.

Several comrades from the Third Rolling Mill were laughing in their hearts. It was Chief Engineer Gao's old habit to treat everyone to a meal whenever a major milestone in the project came about, but this time he found someone to pay.

What they didn't know was that it was actually Gao Zhendong who approved Lu Gong to pay the money.

While Engineer Lu arranged for people to seal the products and pack up the testing equipment, he asked Chief Engineer Lu from Factory 1274 for help in arranging meals. He couldn't bring a large group of people to his own unit, so the matter could only be solved in the cafeteria of Factory 1274. He would only be responsible for signing, and he didn't even have to give cash, and the two units would naturally settle the bill.

On the way to the cafeteria, Mr. Lu also reported to Gao Zhendong another matter that he was concerned about.

"Boss Gao, last time you asked us to try to see how many basically identical infrared photodiodes we could make from one crystal. We have also done some preliminary analysis and design on this matter, and the results are not bad."

Gao Zhendong's mood brightened up: "Oh? Tell me about it."

Engineer Lu nodded and said, "If you just want the smallest infrared photodiode, we have done some analysis. Based on the size of the mercury cadmium telluride crystal, we can probably make it 0.8mm in length, width and 1.5mm in height and still guarantee performance."

They were making an orthogonal quaternion detector, which had requirements for the detector structure, so the diode had requirements for shape and size. Gao Zhendong just wanted the smallest infrared photodiode while ensuring performance, so he could consider making it as small as possible.

This size is the limit of their analysis. If it is smaller, both physical processing technology and electronic component processing technology will encounter some problems.

After listening to this, Gao Zhendong nodded and began to calculate rapidly in his mind.

According to the existing capabilities, it is basically possible to manufacture crystals with a volume of about 150 cubic millimeters. Based on the volume calculation alone, plus the cutting consumption, the HgCdTe crystal required for each photodiode is considered to be 1*1*1.8, and roughly 80 diodes can be processed. Taking into account the corners, processing losses, yield rate and other factors, this number is 7% off. Gao Zhendong was delighted to find that he could use a HgCdTe crystal to process a 1*56 linear array!

Of course, this is just a theoretical calculation, and the actual situation may not be so optimistic, but at least we have to make it work in theory before we can consider other things.

This result made him very happy and he assigned a task to Lu Gong.

"Mr. Lu, I will give you a few large crystals later. You can make your own theoretical calculations and submit them to Factory 1274 to make a few sets of infrared photodiodes. As for funding, please ask me directly. I will give it to you personally."

This year, Gao Zhendong has been writing books continuously, and he has also received royalties from the printing of some old books. He can still afford to publish a few sets, especially when he only needs to consider the cost of materials and processing fees. It is actually not that expensive, at least not a big deal for him.

Although he was surprised that Gao Zhendong paid out of his own pocket, Lu Gong knew that there were many things he couldn't ask casually, especially about Gao Zhendong.

He must have his own reasons for doing this.

Mr. Lu readily agreed to this matter.

Gao Zhendong turned around and discussed with Mr. Lu about the progress of other processes except the diffusion furnace.

President Lu smiled and said, "Overall it's OK. We are familiar with the packaging part, and your request is not too exaggerated. We are making improvements based on the existing equipment, so it's not a big problem. It's not finished yet, but the progress is within our expectations."

"What about the resistance heating vacuum evaporation machine?"

"That's easier to do. You want to do aluminum vapor deposition. The melting point of this material is not high, so it's not very difficult to do. To put it bluntly, it's just like boiling water, except that it's not water that's being boiled, but aluminum. The method we use is more direct, which is to use tungsten filaments to heat. If the temperature is not high enough, we increase the current."

The melting point of tungsten is far beyond the boiling point of aluminum at normal pressure, so there is no problem in doing this.

Miracles come from great efforts. Gao Zhendong had expected this. In the early days of aluminum wire evaporation for integrated circuits, there were no high requirements for thickness, smoothness, density, etc. The idea was to just coat the wire thicker if it really didn't work.

It feels so good to be involved in technology at its early stages.

"Done it?" Gao Zhendong was still quite happy.

"Not yet. Now that the diffusion furnace is basically ready, we can turn to that. Although the two things have completely different uses, there is still a high degree of professional overlap in terms of control methods and specific research. Several comrades in your factory have been busy with the diffusion furnace renovation for some time."

For Factory 1274, Fang Yinghong and other comrades with rich experience in automatic control provided great help. After all, they worked under Gao Zhendong, and the knowledge and experience they possessed in automatic control were "slightly" beyond those of the comrades in Factory 1274.

Therefore, when the transformation of the diffusion furnace occupied several of them, the remaining actual debugging work would be affected after the prototype of the resistance heating vacuum evaporation machine was built.

Gao Zhendong was not in a hurry because he didn't know what the optical system of the lithography machine was like yet.

When they arrived at the cafeteria, Director Lu from 1274 was already waiting there. Director Tang had already sent someone to report to him about Gao Zhendong's arrival, but he was busy with work and couldn't just go to the process workshop to look for him, so there was no need to do that.

But he had to show up for the meal, and when he saw Gao Zhendong, Director Lu greeted him very warmly.

I have to be enthusiastic, otherwise I would feel bad.

Even if the process modification proposed by Gao Zhendong is not used on integrated circuits, it will significantly improve the yield rate of their existing products.

They are already planning to use the results of the diffusion furnace transformation and promote it to all the diffusion furnaces in the factory. In this regard, their participation in the integrated circuit process transformation work has not been in vain.

Now that Gao Zhendong has come in person, it is only logical and reasonable that as long as he is in the factory, he has to show up no matter what.

With the warm hospitality of comrades from Factory 1274 and the Research Institute, Gao Zhendong got home by car at around 9 o'clock. Just in time, he and Xie Jianye were brought back in one car. The car went back to the factory first, and then they rode back by themselves. It felt like they had nothing better to do.

When Lou Xiao'e saw Gao Zhendong coming back and drinking, she quickly brought him tea. It was just right for her and Chen Yuehong to have dinner together.

(End of this chapter)