1 nm process. In semiconductor manufacturing, the "1 nm process" represents the next significant milestone in MOSFET (metal–oxide–semiconductor field-effect transistor) scaling, succeeding the "2 nm" process node. It continues the industry trend of miniaturization in integrated circuit (IC) technology, which has been essential for improving performance, increasing transistor density, and reducing power consumption.

The term "1 nanometer" has no relation to any actual physical feature (such as gate length, metal pitch or gate pitch) of the transistors. According to the projections contained in the 2021 update of the International Roadmap for Devices and Systems published by the Institute of Electrical and Electronics Engineers (IEEE), a "1 nm node range label" is expected to have a contacted gate pitch of 42 nanometers and a tightest metal pitch of 16 nanometers. The first 1 nm chips are expected to be launched in 2027.

History
In 2008, transistors one atom thick and ten atoms wide were made by UK researchers. They were carved from graphene, predicted by some to one day oust silicon as the basis of future computing. Graphene is a material made from flat sheets of carbon in a honeycomb arrangement, and is a leading contender. A team at the University of Manchester, UK, used it to make some of the smallest transistors ever: devices only 1 nm across that contain just a few carbon rings.

In 2016, researchers at Berkeley Lab created a transistor with a working 1-nanometer gate. The field-effect transistor utilized MoS2 as the channel material, while a carbon nanotube was used to invert the channel. The effective channel length is approximately 1 nm. However, the drain to source pitch was much bigger, with micrometre size.

Terminology and physical features
The term "1 nanometer" in this context does not correspond to any direct physical measurement or feature of the transistors, such as gate length, metal pitch, or gate pitch. Instead, it serves as a marketing designation or "node range label" used to represent a specific generation of semiconductor technology.

According to the 2021 International Roadmap for Devices and Systems (IRDS), published by the Institute of Electrical and Electronics Engineers (IEEE), a "1 nm" node is projected to feature:

Contacted Gate Pitch: 42 nanometers
Tightest Metal Pitch: 16 nanometers

These values highlight the ongoing divergence between the naming of process nodes and the actual dimensions of the transistors they describe.

Expected advancements
The 1 nm process node will likely rely on advanced materials and novel transistor architectures to overcome physical and economic challenges associated with continued scaling. Technologies anticipated to be part of this generation include:

Gate-All-Around (GAA) FETs: A refinement of FinFET technology, enabling better electrostatic control and scalability.
2D Materials: Ultra-thin materials, such as graphene or transition metal dichalcogenides, may be used for channel layers to achieve higher performance at reduced dimensions.
Extreme Ultraviolet (EUV) Lithography: Further advancements in EUV lithography to create smaller and more precise patterns on silicon wafers.
High-κ/Metal Gate (HKMG): Continued use or improvement of HKMG stacks to enhance transistor performance and minimize leakage.

Development and timeline
As of 2025, the first chips utilizing the 1 nm process were projected to be launched around 2027. Leading semiconductor manufacturers, such as TSMC, Samsung Electronics, and Intel, are expected to pioneer this technology. These companies have already been working on overcoming scaling challenges, including increased power density, heat dissipation, and variability at such small dimensions.

Challenges and future implications
The transition to the 1 nm node represents significant challenges for the semiconductor industry:

Manufacturing Complexity: Producing features at this scale requires precise control and advanced lithographic techniques, which drive up costs.
Material Limitations: Traditional silicon may reach its fundamental limits, necessitating the exploration of alternative materials.
Economic Viability: The increasing cost of research, development, and production raises questions about the affordability of future nodes for widespread adoption.

Despite these challenges, the 1 nm process is expected to play a crucial role in enabling new applications, such as advanced AI processors, 6G communication technologies, and next-generation IoT devices. It will also pave the way for further innovation in the semiconductor industry, reinforcing its central role in global technological development.

Beyond 1 nm
As semiconductor technology approaches the 1 nm process node, researchers are exploring innovative materials and structures to continue device miniaturization and performance enhancement. A notable development in this realm is the creation of transistors with gate electrodes measuring less than 1 nanometer.

Research and technology demos
In 2012 a single atom transistor was fabricated using a phosphorus atom bound to a silicon surface (between two significantly larger electrodes). This transistor could be said to be a 180 pm transistor (the Van der Waals radius of a phosphorus atom); though its covalent radius bound to silicon is likely smaller. Making transistors smaller than this will require either using elements with smaller atomic radii, or using subatomic particles—like electrons or protons—as functional transistors.

In 2018, researchers at Karlsruhe Institute of Technology created a transistor with a working single atom gate.

In July 2024, a team led by Director JO Moon-Ho at the Center for Van der Waals Quantum Solids within the Institute for Basic Science (IBS) in Korea achieved a significant breakthrough. They developed a method for the epitaxial growth of one-dimensional (1D) metallic materials with widths under 1 nm on silicon substrates. This process was utilized to construct a new structure for two-dimensional (2D) semiconductor logic circuits, employing these 1D metals as gate electrodes. The implications of this development are significant. The International Roadmap for Devices and Systems (IRDS) by the IEEE projects that semiconductor node technology may reach around 0.5 nm by 2037, with transistor gate lengths of approximately 12 nm. However, the IBS research team demonstrated that the channel width modulated by the electric field from the 1D MTB gate could be as small as 3.9 nm, surpassing these projections.

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