First 2D, non-silicon computer developed

Summary

The team used metal-organic chemical vapor deposition (MOCVD) — a fabrication process that involves vaporizing ingredients, forcing a chemical reaction and depositing the products onto a substrate — to grow large sheets of molybdenum disulfide and tungsten diselenide 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. “Our 2D CMOS computer operates at low-supply voltages with minimal power consumption and can perform simple logic operations at frequencies up to 25 kilohertz,” said first author Subir Ghosh, a doctoral student pursuing a degree in engineering science and mechanics under Das’s mentorship. Ghosh noted that the operating frequency is low compared to conventional silicon CMOS circuits, but their computer — known as a one instruction set computer — can still perform simple logic operations. “We also developed a computational model, calibrated using experimental data and incorporating variations between devices, to project the performance of our 2D CMOS computer and benchmark it against state-of-the-art silicon technology,” Ghosh said. “Although there remains scope for further optimization, this work marks a significant milestone in harnessing 2D materials to advance the field of electronics.” Das agreed, explaining that more work is needed to further develop the 2D CMOS computer approach for broad use, but also emphasizing that the field is moving quickly when compared to the development of silicon technology. “Silicon technology has been under development for about 80 years, but research into 2D materials is relatively recent, only really arising around 2010,” Das said. “We expect that the development of 2D material computers is going to be a gradual process, too, but this is a leap forward compared to the trajectory of silicon.” Ghosh an...