World’s first 2D-material CMOS computer makes debut

Penn State researchers have created the world’s first CMOS computer based on 2D materials. Made from n-type MoS₂ and p-type WSe₂ transistors, the 2D-CMOS one-instruction circuit is capable of performing simple logic operations. The chip takes in a supply voltage of < 3 volts and operates at frequencies of up to 25 kilohertz. Power consumption is reported to be minimal at a few picowatts. Switching energy is approximately 100 picojoules for CMOS inversion.

High charge carrier mobility independent of channel thickness makes thin layers of transition metal dichalcogenides (general formula: MX₂) prime candidates to succeed silicon in CMOS. Imec has included these materials in its roadmap, tentatively scheduling their introduction in high-volume production by the end of the next decade.

The Penn State team used metal-organic chemical vapor deposition (MOCVD) to grow large sheets of 2D materials and fabricate over 1,000 of each type of transistor. By carefully tuning the device fabrication and post-processing steps, they were able to adjust the threshold voltages of both n- and p-type transistors, enabling the construction of fully functional CMOS logic circuits.