China and the United States put aside their differences and join hands to achieve an unprecedented achievement: the first graphene semiconductor

JVTech News China and the United States put aside their differences and join hands to achieve an unprecedented achievement: the first graphene semiconductor

Tech world today: Silicon against the backdrop of tensions between China and the United States

There is rivalry between China and the United States. This constant tension between the two superpowers is expressed on all strategic fronts for the country’s economic development. Of course, high tech is one of its strategic fronts.

In the current situation where new economic sanctions are being imposed almost daily and new aggressive announcements are being made, It is surprising to see both the giants joining hands Undertake joint tech projects. And if the sudden collaboration between China and the United States is already a surprise, look at this collaboration In the semiconductor sector, an industry over which the two countries have been waging quite violent open warfare for years, seems almost impossible. And yet…

To understand what graphene is doing thereIt is important to return to the importance of silicon in the world of integrated circuits. This detour is extremely important, you will understand. Silicon is a chemical element. After replacing germanium in the 1960s, it has become A material of choice in the semiconductor industry, thus dominating the electronics market due to its excellent physical properties. Moreover, if we talk about Silicon Valley to designate the high concentration of high-tech companies in the San Francisco Bay Area, it is precisely because all these companies are fueled by silicon.

However, silicone is not perfect. To make a chip, you have to use huge, highly technical machines: photolithography machines. As photolithographic processes evolve, We have reached the physical limits of silicon, so finding new materials capable of replacing it has become crucial. Of course, scientists have been working on this topic for many years and have already discovered many promising candidates. We can talk, for example, of gallium arsenide (GaAs), or the cubic boron arsenide (c-BAs) favored by MIT. As you understand, we will not focus on these ingredients with fancy names in this article but further on Another candidate to replace silicon: graphene.

Electrons, holes and electric current

Graphene has been a candidate to replace silicon for nearly twenty years. After two decades of long research, a major breakthrough has just been reached: Well, we found a way to make graphene-based semiconductors. This “we” designates two research institutions that have joined forces, a historic alliance between Tianjin University in China and the Georgia Institute of Technology in the United States.

Before discussing the properties that make graphene so interesting for the production of semiconductors, it is worth recalling a few. Basic concepts. A semiconductor is an element or compound that, under certain conditions of pressure, temperature, or when exposed to radiation or electromagnetic fields, behaves like a conductor and therefore offers some resistance to the movement of electric charge.

The main reason metals are good conductors of electricity is that they contain a large number of electrons that can move easily without being attached to a particular atom. What we call “electric current” is nothing but the ability of electrons to move. One of the properties of semiconductors is the mobility of “electron holes”. This is where things will get a little complicated.

To popularize the notion of electron holes, imagine that electrons are ping-pong balls bouncing around a box. Each ball represents an electron and the box represents a material, such as a piece of metal or a semiconductor. In a semiconductor, when energy is supplied (such as by electricity or light), some of the ping-pong balls are pushed out of place. When the ping-pong ball (the electron) leaves its spot, it leaves behind a small void. Scientists call this void a “hole”. Now, although a hole is not a physical object like a ping-pong ball, it does behave. In the world of electrons, a hole attracts a nearby electron, which jumps into the hole to fill it. But by leaping, they make a new one where they came from. This creates a kind of dance where electrons jump from hole to hole. In the flow of electric current, these holes play as important a role as electrons. We can say that they move through the material, although technically it is the electrons that move and the holes that appear to move. So electron holes are a way of describing the movement of electrons in a semiconductor.

Graphene has just opened a door that could revolutionize electronics

So we finally come to our Chinese and American scientists. Researchers have recently developed a new semiconductor material derived from graphene called “epigraphene”. What makes it particularly attractive is that electrons can move faster in it than in silicon, the most widely used semiconductor material today.

Thanks to the holes we just talked about, electrons can move ten times faster in epigraphene than in silicon and twenty times faster than in other semiconductors. This property may make epigraphene very important for future developments in the field of electronics.

In his article published in a prestigious scientific journal Nature, the researchers explain in detail the physicochemical properties of epigraphene. It is worth reading if you are comfortable with material physics. Almost always with research papers, although scientists are enthusiastic, they are modest and cautious about their findings. therefore, They recognize that their achievement is only the first step. The research was led by Walt A. De Heer says:

We don’t know where it will end, but what we do know is that we are opening the door to a paradigm shift in electronics. Graphene is the next step.

Let’s hope so. Let’s hope this research bears fruit and we finally have a real alternative to our expensive silicon. We will see.