World’s First Non-Silicon 2D Computer Developed

Silicon, the foundation of nearly all modern electronics from smartphones to electric vehicles, may soon have a formidable rival. Researchers led by Penn State have developed a functional computer made entirely from two-dimensional (2D) materials in a push for thinner, faster, and more energy-efficient devices.

Published in Nature, the study describes the successful creation of a complementary metal-oxide semiconductor (CMOS) computer that operates without any silicon. CMOS technology is essential to most electronic devices, and until now, it has been inseparable from silicon. This new development demonstrates that 2D materials, just one atom thick, can replicate and potentially surpass silicon’s capabilities.

The team used two different 2D materials to fabricate the necessary transistors for CMOS logic: molybdenum disulfide for the n-type transistors and tungsten diselenide for the p-type ones. Unlike silicon, these materials retain their superior electronic properties at an atomic scale, which is crucial as the electronics industry pushes toward ever-smaller and more efficient devices.

Professor Saptarshi Das, who led the research, noted that while silicon has powered decades of technological advancement, its limitations become apparent at nanoscale dimensions. As field-effect transistors (FETs) shrink, their performance degrades. In contrast, 2D materials maintain their integrity even at extreme miniaturization, offering a path forward for continued innovation.

The breakthrough here lies not just in creating individual components, but in integrating them into a working computer system. Previous efforts had demonstrated basic circuits using 2D materials, but scaling up to a functional computer capable of performing real operations had not been achieved—until now.

Using metal-organic chemical vapor deposition (MOCVD), the researchers grew large sheets of both materials and fabricated over 1,000 n-type and p-type transistors. By fine-tuning their fabrication process, they adjusted the threshold voltages to achieve fully operational CMOS logic circuits.

The result was a simple, silicon-free CMOS computer, known as a “one instruction set computer,” capable of executing basic logic functions at frequencies up to 25 kilohertz. While this is far slower than conventional silicon-based chips, the device marks a foundational step toward developing practical electronics using 2D materials.

First author Subir Ghosh, a doctoral student in Das’s lab, noted that the team also developed a computational model to project how their 2D CMOS technology could eventually compare with state-of-the-art silicon systems. The model, grounded in experimental data, suggests strong potential for future optimization.

Das acknowledged that the road ahead involves more research and development, but emphasized the remarkable pace of progress. Compared to silicon, which has been under refinement for nearly 80 years, research into 2D materials only began in earnest around 2010. To have already created a functional CMOS computer in such a short time represents a major leap forward.