Scientists have developed a new type of ultra-thin crystalline semiconductor that can move electrons seven times faster than conventional semiconductors, which could have big implications for electronics.
According to a study published July 1 in the journal Materials Physics TodayThe physicists have created extremely thin films from a crystalline material called ternary tetradymite.
The film is just 100 nanometers wide, or about 1/1000 the width of a human hair. Molecular Beam Epitaxyis a process in which molecular beams are precisely controlled to build materials atom by atom. This process allows for the construction of materials with minimal defects and imperfections, thereby improving electron mobility (a measure of how easily electrons can move through a material under an electric field).
When the scientists passed an electric current through the film, they recorded the electrons moving at a record-breaking speed of 10,000 centimeters squared per volt second (cm^2/Vs) — by comparison, electrons normally travel at about 1,400 cm^2/Vs. Standard silicon semiconductorand quite slow Conventional copper wiring.
Related: New sodium-ion battery technology could allow future EVs to charge in just seconds
This extremely high electron mobility leads to improved electrical conductivity, which in turn enables the development of more efficient, more powerful electronics that emit less heat and waste less energy.
The researchers likened the film’s properties to a “highway without traffic” and said such materials “will be essential for more efficient, sustainable electronics that can do more with less power.” Potential applications, the scientists say, include wearable thermoelectric devices, which convert waste heat into electricity, and “spintronic” devices, which process information using electron spin rather than electric charge.
“What people have achieved so far in terms of electronic mobility in these systems has been like a traffic jam on a road under construction: congested, undriveable, dusty and confusing.” Jagadish MoodelaMIT physicists statement“With this new optimized material, it feels like you’re driving on a traffic-free Massachusetts Pike.”
The scientists subjected the crystalline films to extremely low temperatures and measured the material’s electron mobility. magnetic fieldA current was passed through it and measured. Quantum OscillationThis occurs when electrical resistance varies with the magnetic field.
Even tiny defects in the material can impede the movement of electrons and affect their mobility, so the scientists hope that refining the process for making the film will yield even better results.
“This shows that with the right control over these complex systems it’s possible to take even bigger steps forward,” Moodela said. “This shows that we’re on the right track, and that we have the right systems in place to make further progress in continuing to perfect this material down to even thinner films and close-coupled structures for use in future spintronics and wearable thermoelectric devices.”
