Integrated circuits are a new type of semiconductor device developed in the 1950s and 1960s. It is a semiconductor manufacturing process such as oxidation, photolithography, diffusion, epitaxy, and aluminum evaporation. The transistors, resistors, capacitors, and other components required to form a circuit with certain functions and the connecting wires between them are all integrated into a small piece of silicon. On-chip, then solder the electronics packaged in a single package. For sixty years, semiconductor integrated circuits based on monocrystalline silicon have become ubiquitous and become a powerful pillar of the entire information technology. Computers, mobile phones and other digital appliances that depend on the existence of integrated circuits have become an indispensable part of modern social architecture. The digital revolution brought about by integrated circuits is the most important event in human history. The continuous breakthrough in the manufacture of integrated circuits and design technology has also led to rapid development. As early as 1965, Gordon Moore (one of Intel's founders) predicted that when the price was constant, the number of transistors that could be accommodated on an integrated circuit would double every 18 months and performance would double. Looking back at the developments in this field from then until now, as he said. In order to improve performance, people continue to increase the number of silicon transistors on a single chip according to this law. Microchip technology has broken through the process limits over and over again for decades. Today, Intel's third-generation processors have used 22nm technology.
However, as device feature sizes continue to shrink, especially after entering the nanoscale range, this one-dimensional development model of integrated circuit technology faces a series of physical limitations that come from fundamental physical laws. Physical limits also come from physical limitations in materials, technology, devices, and systems. Sooner or later, the silicon chip will come to an end because the size cannot continue to shrink. Which material can replace silicon chips? Scientists are looking for new directions. There are two more viable candidates: one is called "photonic integrated circuit" or "Photonic Integrated Circuits". The main difference from the integrated circuit is the use of photons instead of electrons as the carrier of the data, which has a high transmission speed and a large amount of information. Some PICs devices have been manufactured and successfully used in optical communications, especially fiber optic communications. However, since PICs are also fabricated using photolithographic techniques, they also encounter critical dimensions of the device. Another way that scientists are more optimistic is to replace silicon with CNT Carbon Nanotube.
The first carbon nanotube discovered by humans in 1991 is a one-dimensional quantum material with a special structure (the radial dimension is nanometer, the axial dimension is micron, and the two ends of the tube are basically sealed). A tubular single layer of carbon atoms. Carbon nanotubes are a form of carbon with the same composition as diamond and graphite. The main constituent is carbon. It is an allotrope of carbon. The diameter of the carbon nanotubes is generally several nanometers to several tens of nanometers, and the wall thickness is only a few nanometers, like a hollow cylindrical "cage tube" wound by a wire mesh. It is very small, and the space of the hairline can hold tens of thousands of carbon atoms. Secondly, carbon nanotubes are very tough and can be bent, and the strength-to-weight ratio is the highest among currently known materials. Carbon nanotubes have extraordinary strength, thermal conductivity, and magnetic reluctance, and their properties change with structural changes, from insulators to semiconductors and semiconductors to metals. Its conductivity is extremely strong, 100 times that of copper.