svetikya Chapter 124
Chapter 124
The advancement speed of 1nm chips of Zhonghai Optoelectronics Institute is also very rapid!
First of all, the 1 nm lithography machine was immediately installed in the ultra-clean machine room of Zhonghai Guangke Technology, and the supporting equipment followed the 14 nm process, and some needed to be improved and transformed accordingly, which has been carried out from the first day.
Secondly, Dabai began "magic cave training" for all technical personnel, and carried out real-world operations step by process, step by step, based on Kong Bai's series of 1-nanometer lithography machine technical data.
The third is that a large number of raw material purchases have been carried out since the first day, and in order to hide people's eyes, they are also scattered through several optical semiconductor shareholders and upstream and downstream cooperative manufacturers.
In fact, even if this is the case, it has not escaped the eyes of some people with intentions, this is said later.
Fourth, and most importantly, Mr. Dabai has comprehensively re-optimized the design of the complete set of chip-based overall architecture, and the most critical problem is also the most surprising:
this change is so great that it can be called rebuilding the entire system!
In particular, after discussing with Kong Bai, Dabai adopted a new chip substrate, that is, a new chip substrate material!
The new substrate no one expected, and that is diamond!
That's right, diamonds!
Diamond is an excellent semiconductor material, and it is completely capable of beating the existence of silicon semiconductors!
In fact, when Kong Bai began to study "nuclear diamonds", he noticed that diamonds have the same crystal structure as silicon.
Also an element of the IV main group, carbon has the ability to make semiconductors.
For example, single-layer graphene with a two-dimensional structure and carbon nanotubes with a two-dimensional structure curled have excellent semiconductor properties.
However, due to the problem of the manufacturing process, it is not easy to prepare large sizes, so it is abandoned as a semiconductor substrate.
In this case, you can only retreat to the second place and use diamonds as the substrate for 1-nanometer chips!
Diamond, like silicon crystal atomic structure, is a tetrahedral three-dimensional structure, so theoretically, both diamond and silicon have the performance characteristics of semiconductors.
As we all know, the smaller the transistor, the greater the number of transistors integrated per cross-sectional area, the faster the processor and the higher the computational efficiency.
However, after using traditional silicon-based chips to reach a gate length of 1 nanometer, there will be a serious "quantum tunneling effect".
The reason for this is mainly because with a diameter of 1 nanometer, there are only 4 silicon cells at most, and 1 square nanoplane can hold up to 13 silicon atoms; If it is a three-dimensional sphere with a diameter of 1 nanometer, it contains up to 8 silicon cells, and the number of silicon atoms in the sphere is only 64 at most.
What does that mean? That is, there are too few silicon atoms in the length of 1 nanometer to prevent electrons from penetrating, and it has become a full conductor. That is, the quantum tunneling effect will cause the semiconductor to run out of control of electrons.
Compared with silicon, diamond has excellent characteristics such as high thermal conductivity, high breakdown electric field, high electron mobility, high carrier saturation rate and low dielectric constant, which meets the requirements of higher integrated chips for high temperature, high pressure, high power, high frequency and radiation resistance.
In addition, diamonds have smaller cell and atomic sizes, and in the same length of 1 nanometer, diamonds can hold more carbon atoms without the "quantum tunneling effect" like silicon.
Moreover, the use of diamonds can greatly solve the problem of thermal management imbalance of transistors under high integration.
Therefore, chips made of diamonds can withstand the test of high temperature environment more than silicon chips, and the heat dissipation efficiency is extremely high, especially in large computing centers, the requirements for chip stability!
However, using diamonds as a substrate is all good, except for one bad thing, that is, large-sized diamonds that can be etched by chips are not easy to obtain!
Then, according to the idea of preparing "nuclear diamonds", Kong Bai also used the "chemical vapor precipitation method" to synthesize large-sized diamond flakes for making diamond chips.
The traditional method of artificially manufacturing diamonds is to simulate the environment in which diamonds are produced in nature, and use high temperature and high pressure methods to prepare.
But this condition is extremely harsh, to turn toner into shiny diamonds, at least 2,000 degrees of high temperature and dozens of atmospheres of pressure pressure!
Even under such harsh conditions, the diamond produced, that is, a very small one, cannot be used as a chip substrate at all!
However, by using the chemical vapor precipitation method, it is relatively easy to obtain large-sized diamond flakes.
Specifically, in a closed pressure vessel, a layer of uniform diamond powder is laid at the bottom of the container, and then a certain temperature and pressure are applied to this confined space, and a certain proportion of methane, nitrogen and hydrogen are injected into it, and microwave discharge is carried out synchronously, and the mixed gas is heated at high temperature, so as to promote the carbon in methane into a carbon plasma.
These carbon plasmas are continuously deposited on the diamond powder at the bottom of the pressure chamber, slowly accumulating and hardening over time, and eventually forming diamond flakes.
This method of producing diamonds is very simple in principle, but it is very difficult to actually produce.
Among them, the main reason is that it is necessary to accurately control the mixing ratio of methane, nitrogen and hydrogen, temperature and pressure, plasma concentration and other reaction conditions, and to replenish methane gas in time according to the consumption rate of carbon.
Moreover, the hydrogen element and methyl intermediate of the plasma have strong reducing properties, which can react with many things in the reactor and produce compounds, resulting in impurities doped with other elements in the gas and affecting the semiconductor properties of diamond sheets.
For example, boron, which is very common in glass, is not suitable for the growth of pure diamonds even at very small levels, so the purity of diamond powder as a base layer is also extremely demanding!
However, these difficulties require a long time of exploration for others, but for Dabai, who has huge computing power and genetic algorithms, it is not so difficult!
Kong Bai quickly arranged the experimental task of diamond flake growth, and after more than a day of experimentation, obtained a large amount of data on the growth of diamond flakes.
Subsequently, Kong Bai gave these data to Dabai, and asked her to use genetic algorithms to deduce a relatively optimal diamond growth environment parameter.
He customized a lot of expensive ones, using titanium plates as pressure vessels for the reaction chamber, and diamond powders with extremely high purity.
Then, according to the parameter interval deduced by Dabai, several comparative tests were done to obtain an optimal solution, and then large-scale manufacturing of diamond flakes began!
Because Kong Bai only needs a diamond flake of a little more than 1 millimeter thick, rather than a large diamond for jewelry, the production speed is relatively fast, and in less than four days, more than 200 pieces are produced.
For each batch produced, Kong Bai handed over the flakes to the people of Zhonghai Optoelectronics, and asked them to hurry up, cut and polish them into diamond wafers about 0.9 mm thick, and then began trial production according to the chip manufacturing process that Dabai had trained in.
In this way, in just a few days, the first epoch-making diamond chip was manufactured!