193 Chapter 193 MOCVD

The weather is getting warmer day by day.

Cheng Yongxing has a new job while studying, and that is to chat with him.

Every day, he has to spend an hour or two, staying in front of the telephone, and discussing with technicians in the distance.

In the era without internet, fax and telephone are the most advanced communication tools.

The few drawings taken away by Science Instruments are the design sketches of MOCVD.

The full name of MOCVD is metal organic compound chemical vapor deposition.This Chinese name is actually more difficult to understand than the English name.

There are too many terms involved, including keywords such as gas phase, extension, etc., each of which is enough to exist as a discipline.

The principle of this thing is very complicated to explain, but the actual reaction process is not complicated.The whole process is similar to electroplating, but the medium is not liquid, but gas.

If you have to explain it, it is that in a special environment, two gases undergo a chemical reaction in the air, and the reaction product will be adsorbed to the surface of the heated object, and then be solidified into a part of the surface of the object.

Let's find a video to watch.In words, um, it can be 10,000 words, but it is not clear.

This equipment is a key node in the production of blue LEDs and has many advantages: simple equipment; reactive gas can be accurately adjusted; film thickness can be accurately adjusted; low-pressure epitaxial growth can reduce unintentional doping; the film is larger and more uniform , Suitable for mass production, etc.

No technology is created in a vacuum.The predecessor of MOCVD is vapor phase epitaxial growth (VPE).The current VPE technology is only available in the United States, and it is a kind of embargoed technology.

Therefore, from a common sense, China will never have MOCVD soil.

The reason why Nakamura succeeded was that it imported a VPE from the United States.On the basis of this equipment, he made another transformation and finally built his own MOCVD.

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The reason why Cheng Yongxing knows about this technology mainly comes from the product advertisements of some manufacturers.These technologies belonged to protected patents, so they generously made the technologies into animations, videos, and promoted them everywhere.

The technical content of MOCVD is high, quite high, otherwise this equipment will not appear on the embargo list.

But is it really difficult to manufacture?

Sometimes, being famous is not a good thing. If the blue LED did not win the Nobel Prize, nothing would happen today.

It is the controversy and storytelling of blue LEDs that make related popular science articles overwhelming.

When hearing the news about the blue LED Nobel Prize, Cheng Yongxing looked at the design sketch of this thing, and a bunch of manufacturer promotional videos. He looked left, right, front, and back, but he didn't understand this thing. , Why is it worth the embargo.

This thing, at best, is a high-temperature reaction vessel.

Especially when continuous production is not considered, the structure is simpler.This thing is obviously not of the same order of magnitude as the required technical parameters for the equipment and tanks used in the large chemical projects currently underway.

The Jiangsu and Zhejiang generation, a large number of LED companies, use domestic equipment, don't they use it well?

Just search, there are a lot of papers on MOCVD on the Internet.

Countless people have obtained PhD and master degrees through this thing.And this trend has shifted to undergraduate thesis.

Does it really answer that sentence?

What can be copied as long as it is taken by Rabbit's omnipotent cottage factory?

If this is the reason, it should be embargoed.

Perhaps the biggest obstacle to the development of China's semiconductor equipment technology is not just manufacturing technology, but also a large number of patents.

Many technologies have been registered by others, and you can’t use them if you see them!

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However, there is another interpretation: difficulty.

Nakamura was able to make a breakthrough in LED technology because he creatively used the heating technology inside the cavity.This makes the manufacturing technology and reaction control of the entire reaction chamber exponentially lower.

Before this process improvement, the reaction chamber, even the piping and the gas outlet, were all quartz.Compared with the easy processing of metals, the difficulty of using quartz as a high-temperature reaction vessel can be imagined.

It is this improvement that led Nakamura to complete the next work independently with his own ability.

At this moment in time, the same improved technology has also brought the Chinese people the possibility of overtaking in curves.

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The content in these propaganda videos and the content reported by the news were used by Cheng Yongxing, and they were continuously transmitted thousands of miles away via telephone and fax.

The design sketch this time is based on these public information.

As for the details of the heater Nakamura used, he really did not find out.The Japanese strategy is to produce and sell.They make their own processing equipment and produce their own products, so they will not release detailed designs of production equipment.

Especially for the details of the heater, Cheng Yongxing searched for the information for a long time at the time, but only found, "Top Secret in Top Secret", this weird wording.

What's so top secret about this? Just grab a postgraduate thesis and it's everywhere.

The students of later generations also struggled for a paper, and the various proposals they put forward were strange.

In a sense, the current competition between the two parties is also a competition between two processes and two technological routes.

Both sides are desperately running forward.