Scientists have developed a device that could perform like a brain or have brain-like functions. It is known as “memtransistor,” which is a multi-terminal device made from a single layer of the semiconductor molybdenum disulfide (MoS2).
Scientists have been looking for ways to make computers act as neuromorphic or brain-like for years. And now they are on the verge of reaching this goal.
The discovery described in Nature indicates that the new device could execute neural functions just like the brain. Mark C. Hersam, a Walter P. Murphy Professor of Materials Science and Engineering in Northwestern’s McCormick School of Engineering, and his colleagues led the discovery and research.
Hersam explained that computers have separate processing and memory storage units, unlike the brain which uses neurons to perform both functions. He further said that neural networks could achieve complicated computation with significantly lower energy consumption compared to a digital computer.
With the merging of the uses of memristor and transistor, the “memtransistor” emerges which consists of multiple terminals and operates similarly to a neural network. Memtransistors could operate like a neuron and perform memory and information processing. A human brain has about billions of neurons, which are nerve cells or nerve fibers in the nervous system that process and transmit information.
According to Nature, memristors are two-terminal passive circuit elements that could be used in non-volatile resistive random-access memory. They are also useful in neuromorphic computing. These devices have higher endurance and could read and write faster than flash memory. Moreover, they could provide multi-bit data storage.
In the study, the scientists developed the memtransistor using the thin MoS2 together with well-defined grain boundaries that impact the flow of current. The atoms are arranged into ordered domains known as “grains” within the material. Once a large voltage is applied, the grain boundaries produce atomic motion that triggers a change in resistance, according to Phys.org.
The team also utilized a continuous film of polycrystalline MoS2 that consists of numerous smaller flakes. With this, the researchers could scale up the device from one chip into many devices across the whole wafer.
Then, the scientists attached additional electrical contacts after fabricating the memtransistors uniformly in the entire wafer. The new device consists of seven terminals, each of which manages the current.
Hersam said that their new device allows many contacts similar to the multiple synapses in neurons. Currently, the scientists are now working on developing a memtransistor that is faster and smaller. They also plan to enlarge the production of the new device for manufacturing purposes.