The photoresist being developed by the 08 laboratory is also part of National Semiconductor's backup technology.
During this period, photoresist was not a product that was prohibited from being sold to China from abroad. There were many photoresist manufacturers internationally, and domestic semiconductor companies could easily purchase various photoresists, and the prices were not expensive.
However, the country still assigned the task of developing photoresist to Maple Forest Research Institute. The purpose was to ensure that in the event of a foreign blockade, the country would be able to provide suitable photoresist to ensure the integration of a few national security issues.
Production of the circuit is not affected.
Everyone knows that the production cost of domestically developed photoresist will be much higher than that of imported products, and the quality is far inferior, and it is absolutely uncompetitive in the market.
However, when the life and death of the country is at stake, are these issues still necessary to consider?
Many technologies studied by Maplewood Research Institute have such characteristics. Compared with Western countries, these technologies are one to two generations behind on average. Even if they are given to others, they will not take them seriously.
But this does not mean that the secrecy system of Maplewood Research Institute is redundant. The purpose of secrecy is to prevent the opponent from knowing where our research progress has been. No matter the opponent overestimates or underestimates our level, he or she will lose control in the battlefield or the economy.
We make some big or small mistakes in the game, and these mistakes may become our opportunities.
This is a survival strategy for the weak.
Gao Fan didn't know much about the country's overall strategy, but when he heard the word "photoresist" from Yun Zhongming, he had an idea:
Maybe, you can do something yourself.
"Brother Xu, I heard from Director Bi that what you are studying is G-line photoresist. Are you involved in i-line and KrF photoresist?" Gao Fan asked.
The Director Bi he was talking about was named Bi Liansheng, the director of Laboratory 08, a middle-aged intellectual with an unsmiling tone.
Lithography technology can be divided into many categories according to the different light sources used, or it can also be called different generations.
In the 1960s, when photolithography technology first appeared, ordinary visible light sources were used. The photolithography machine at that time actually used a large light bulb to illuminate the mask, which was no different from developing photos in a photo studio.
In the 1980s, the light source evolved to use 436 nanometer and 365 nanometer light sources produced by high-pressure discharge mercury lamps. The former is called G-line light source, and the latter is called i-line light source. Both are near-ultraviolet light sources.
After the 1990s, 248 nm, 193 nm and 157 nm light sources using excimer lasers appeared, called KrF, ArF and F2 light sources respectively, which are deep ultraviolet light sources.
As for the EUV lithography machine, known as the "Crown Pearl", it uses a 3-nanometer extreme ultraviolet light source, and its appearance will not be until after 2010.
Nowadays, G-line light source is still the mainstream light source used in integrated circuit manufacturing. I-line light source lithography machines have been introduced, but they have not yet been promoted on a large scale. As for KrF, the laboratory concept has been proposed, and it will have to be put into use in real time.
Ten years later.
The principle of photolithography is the same as developing photos. First, the circuit diagram must be made into a negative, called a mask. The light source shines through the mask on the chip substrate coated with photoresist.
Photoresist is composed of resin, sensitizer, solvent and additives. The sensitizer reacts when exposed to light, dissolving the photoresist in the exposed area. This is equivalent to copying the circuit pattern on the mask to the chip base.
On the material.
Subsequently, etching, ion implantation, packaging and other operations are performed, and a chip is completed.
The selection of photosensitizer in photoresist is closely related to the light source, which involves the changes of compounds under the action of light of different wavelengths, and the mechanism is very complex.
Xu Yun knows these concepts. He was originally a student in the Department of Physics. Maplewood Research Institute hired his teacher to participate in this project because it involves some optical issues. He has been immersed in the project team for so long.
, are naturally very knowledgeable about these issues.
Hearing Gao Fan's question, Xu Yun could only put aside the distracting thoughts in his mind and answered seriously: "The focus of our current research is G-line photoresist, which is currently the most widely used.
"In terms of i-line photoresist, Director Bi has mentioned it several times in laboratory meetings, allowing everyone to have time to do some accumulation, but the conditions are not mature yet. As for KrF photoresist, it seems that foreign countries have just begun to study it.
Bar?"
"You said the conditions for i-line photoresist are immature. What do you mean?" Gao Fan asked.
Xu Yundao: "That's not what I said, but what Director Bi said. There are no photolithography machines that use i-line light sources in China, and there are not many abroad. Is it too hasty to study i-line photoresist?"
"That's what I want to tell you." Gao Fan said, "By the way, Senior Brother Xu, have you heard of Moore's Law?"
"Of course I've heard of it." Xu Yun said angrily, "Isn't it that the number of transistors on integrated circuits doubles every two years? Several of our teachers have mentioned it in class."
"As expected of HKUST, its thinking is very avant-garde." Gao Fan gave a thumbs up and praised, but Xu Yun gave him a blank stare.
Moore's Law was proposed in 1965, but it did not receive people's attention until the mid-1970s. With the rapid development of integrated circuit technology, Moore's Law has been confirmed repeatedly, and for a time it was highly respected in the Western technology and industrial circles.
At this time, China is completely transparent in the global semiconductor market and is not qualified to comment on the development of the semiconductor industry. Therefore, few people will pay attention to or mention Moore's Law.
Xu Yun said that several of his teachers mentioned Moore's Law in class, and Gao Fan naturally wanted to express his admiration. But with his identity, he put on such a face to praise the University of Science and Technology of China, how could Xu Yun not express his admiration for him?
disdain.
"Now that you know Moore's Law, think about it, at what speed will chip manufacturing technology develop? G-line lithography machines will definitely become obsolete soon, and next-generation i-line lithography machines will become popular rapidly. Within ten
In 2020, the mainstream of the market will be KrF lithography machines." Gao Fan said eloquently.
Xu Yun thought for a moment in his mind, nodded and said: "You are right, but this is also the trend of the international market, right? Our country can't even master the G-line lithography machine. The KrF you are talking about is useless.
It will have to be 20 years from now."
"Why can't we aim at the international market?" Gao Fan looked at Xu Yun, "Making photolithography machines requires high-precision machine tools, and we can't build them at the moment. But the threshold for photoresist technology is not high, so why can't we