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2D Semiconductor Manufacturing Hits 1,000x Speed Boost

Chinese researchers achieved a 1,000-fold increase in 2D semiconductor manufacturing speed using a liquid gold CVD technique for next-generation chips.

By the Born to Engineer editorial team Published 5 min read

2D Semiconductor Manufacturing Hits 1,000x Speed Boost

Key points

  • Chinese researchers developed a CVD technique that grows 2D semiconductor films 1,000 times faster than previous methods
  • The key innovation is a liquid gold and tungsten bilayer substrate that accelerates crystal growth
  • The tungsten silicon nitride films show p-type behaviour, addressing a critical gap in 2D electronics
  • 2D materials could extend chip performance beyond the limits of silicon and Moore's Law
  • Scaling from laboratory films to 300 mm production wafers remains a major engineering challenge

    • For more than fifty years, the semiconductor industry has obeyed a fairly consistent pattern: roughly every two years, the number of transistors that fit on a chip doubles, performance improves, and costs per transistor fall. This trend, known as Moore’s Law, has shaped everything from smartphones to supercomputers. But silicon, the material that made it all possible, is approaching a physical wall. Below about 1 nanometre, quantum effects cause electrons to tunnel through barriers they should not cross, and heat dissipation becomes unmanageable. The industry needs a new class of materials. In April 2026, a team of Chinese researchers announced they may have found a faster way to make them.

    The team, led by Zhu Mengjian at the National University of Defence Technology, with Ren Wencai and Xu Chuan from the Institute of Metal Research, developed a new chemical vapour deposition (CVD) technique that grows 2D semiconductor films roughly 1,000 times faster than conventional methods, as reported by Interesting Engineering. The key innovation was replacing the standard substrate with a liquid gold and tungsten bilayer. On this surface, monolayer films of tungsten silicon nitride grew at rates of approximately 0.02 millimetres per minute, compared to the previous benchmark of roughly 0.001 millimetres over five hours. The resulting films measured about 36 by 18 millimetres, large enough to begin thinking about wafer-scale 2D semiconductor manufacturing.

    Two-dimensional semiconductors are materials just a few atoms thick, sometimes a single atom layer, that conduct electricity in ways fundamentally different from bulk silicon. Graphene, a single sheet of carbon atoms, was the first famous example, but it lacks the bandgap needed to switch transistors on and off. Transition metal dichalcogenides such as molybdenum disulfide (MoS₂) and tungsten diselenide (WSe₂) do have band gaps, and they can be made thin enough that quantum confinement effects actually improve their electrical properties rather than degrading them.

    The 2D semiconductor manufacturing bottleneck

    The problem has always been production speed. Growing a uniform monolayer of a 2D material over a large area has historically been painfully slow. CVD, the standard technique, involves flowing precursor gases over a heated substrate and waiting for the material to crystallise one atom at a time. Scaling this from laboratory samples a few millimetres across to the 300-millimetre wafers used in commercial chip fabrication has been a fundamental bottleneck.

    The tungsten silicon nitride films produced by the Chinese team have another property that makes them particularly interesting: tunable p-type doping. In semiconductor physics, p-type materials carry positive charge through “holes,” the absence of electrons in the crystal lattice. Most 2D materials developed so far are n-type, meaning they carry current through electrons. Building a functional circuit requires both types, just as a CMOS logic gate needs both NMOS and PMOS transistors. The shortage of viable p-type 2D materials has been, as Zhu described it, “a critical bottleneck and a fiercely competitive frontier.”

    The tungsten silicon nitride films demonstrated high hole mobility and high ohmic current density, along with the mechanical strength and chemical stability needed for practical device fabrication. Whether these laboratory results translate to commercial-scale production remains an open question. Integration into existing CMOS architectures, the standard framework for modern chip design, will require further engineering work.

    Engineering deep dive

    Why 2D semiconductor manufacturing could reshape electronics

    To understand why 2D materials matter, start with the transistor. A transistor is a switch: apply a voltage to the gate electrode, and current flows between the source and drain. Make the transistor smaller, and you can fit more switches on a chip. In silicon, the channel through which current flows is carved from a three-dimensional crystal. As the channel shrinks below about 5 nanometres, electrons begin to behave less like particles following well-defined paths and more like probability waves that leak through thin barriers, a phenomenon called quantum tunnelling. This is the point at which classical scaling breaks down.

    A 2D semiconductor channel is different. Because the material is inherently just one or a few atoms thick, there is no need to thin it down. Quantum confinement, the restriction of electron movement to two dimensions, actually increases the material's bandgap and reduces leakage currents. For students studying A-level Physics, this connects to the particle-in-a-box model: confining a quantum particle to a smaller space increases its minimum energy. In a transistor, a larger effective bandgap means the "off" state is more truly off, which reduces power consumption.

    Chemical vapour deposition works by introducing gaseous precursors into a reaction chamber containing a heated substrate. The precursors decompose on the hot surface and react to form a thin film. In conventional 2D CVD, the growth rate is limited by precursor diffusion to the substrate surface and by surface kinetics of nucleation and crystal growth. The Chinese team's innovation was to use a liquid gold and tungsten bilayer substrate. The liquid gold surface eliminates grain boundaries, provides a uniformly smooth template for crystal nucleation, and allows precursor atoms to diffuse across the surface far more rapidly than on a conventional solid substrate. The tungsten layer beneath supplies one of the film's elemental components, reducing reliance on gas-phase delivery.

    The distinction between n-type and p-type semiconductors is fundamental to all modern electronics. In an n-type material, the dominant charge carriers are electrons. In a p-type material, the carriers are holes, which behave as positive charges moving through the lattice. Every CMOS circuit, from the processor in your phone to the controllers in a car, relies on complementary pairs of n-type and p-type transistors. Without both, you cannot build the basic logic gates (NAND, NOR, NOT) that underpin digital computation. This is why the ability to produce p-type 2D materials at scale is so strategically important.

    Tungsten silicon nitride is a relatively new entrant in the 2D materials catalogue. Its crystal structure provides natural p-type behaviour without external doping, simplifying fabrication. The material also shows strong mechanical properties, meaning it can withstand the stresses of multi-step lithographic processing without cracking or delaminating from the substrate. Thermal conductivity matters too: one persistent challenge with 2D transistors is heat removal, because ultra-thin materials have limited cross-section for heat flow. Tungsten silicon nitride's reported thermal properties suggest it handles this better than some alternatives, though independent verification is still needed.

    The path from a 36 × 18 mm film to a 300 mm production wafer is not simply a matter of scaling up the CVD chamber. Uniformity across a larger area becomes exponentially harder to maintain. Defect density must fall to levels where billions of transistors on a single chip can all function reliably. And the new material must be compatible with existing lithography, etching, and metallisation processes, or those processes must be re-engineered. This is a multiyear effort involving collaboration between materials scientists, process engineers, and device physicists.

    Links to the curriculum: A level

    The 2D semiconductor field is moving faster than it was five years ago, driven by investment from both national governments and commercial chipmakers who see the end of conventional silicon scaling approaching. Whether tungsten, silicon nitride, or another material ultimately enters mass production, the engineering principles being developed now, liquid-metal substrates, rapid CVD growth, and tunable doping, will shape the next generation of electronics. The chip may end up being three atoms thick. Getting there will require thinking on an altogether larger scale.

    Credit via interestingengineering.com

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