Penn State's 2D computer represents a significant milestone in electronics research, published in Nature in June 2025. The team, led by Professor Saptarshi Das, created a complementary metal-oxide semiconductor (CMOS) computer using two different atom-thick materials instead of traditional silicon: molybdenum disulfide for n-type transistors and tungsten diselenide for p-type transistors.12 This innovation addresses a fundamental limitation in electronics—as silicon devices shrink, their performance degrades, while 2D materials maintain their exceptional properties even at atomic thickness.1

The researchers fabricated over 2,000 transistors to build what's known as a "one instruction set computer" capable of performing simple logic operations at up to 25 kilohertz.23 While this operating frequency is modest compared to conventional silicon circuits, the achievement is remarkable considering 2D materials research only began around 2010, compared to silicon's 80-year development history.12 The team also developed computational models to benchmark their creation against current silicon technology, demonstrating the potential for thinner, faster, and more energy-efficient electronics in the future.3 This work was supported by Penn State's 2D Crystal Consortium Materials Innovation Platform, which provided the specialized facilities and tools needed to realize this silicon-free computing breakthrough.1

The Penn State team's decision to replace silicon with molybdenum disulfide (MoS₂) and tungsten diselenide (WSe₂) represents a fundamental shift in computer architecture. These two-dimensional materials offer critical advantages over silicon, particularly as devices continue to miniaturize. While silicon's performance deteriorates at extremely small scales, these 2D materials retain their exceptional electronic properties even at atomic thicknesses, opening promising pathways for future electronics.12

The researchers specifically selected molybdenum disulfide for n-type transistors and tungsten diselenide for p-type transistors to create a complementary metal-oxide-semiconductor (CMOS) architecture. This pairing was crucial because CMOS technology requires both n-type and p-type semiconductors working together to achieve high performance with minimal power consumption.2 Using metal-organic chemical vapor deposition, the team grew large sheets of both materials and fabricated over 1,000 transistors of each type, carefully tuning the fabrication process to adjust threshold voltages and enable fully functional CMOS logic circuits.2 These materials aren't just replacements for silicon—they represent an entirely new paradigm in computing that could eventually lead to dramatically slimmer, faster, and more energy-efficient electronic devices.

The 2D materials used in Penn State's atom-thick computer open up exciting possibilities beyond traditional computing. These transition metal dichalcogenides (TMDs) like molybdenum disulfide and tungsten diselenide exhibit extraordinary optoelectronic properties that make them ideal for next-generation applications.1

• Flexible electronics: Unlike rigid silicon, these 2D materials can be integrated into bendable substrates, enabling truly flexible devices and displays.1

• High-speed electronics: The direct bandgap nature of monolayer TMDs (ranging from 1.56 to 1.65 eV for molybdenum tungsten diselenide alloys) makes them promising for ultrafast computing applications.2

• Energy harvesting: WSe₂ has shown potential in photovoltaic applications, with researchers developing printed active layers for solar energy conversion.3

• Chemical and environmental sensing: Both MoS₂ and graphene transistors can be modified to function as chemical sensors, potentially enabling "smart skin" systems that can be discretely integrated into and sense their environment.3

• Electrocatalysis: Functionalized MoSe₂ and WSe₂ have demonstrated enhanced activity for hydrogen evolution reactions in both acidic and alkaline media, showing potential for clean energy applications.4

While the current 2D computer operates at a modest 25 kilohertz with minimal power consumption5, these materials represent the beginning of a new computing paradigm that could eventually outperform silicon in specialized applications requiring extreme thinness, flexibility, or novel sensing capabilities.