Lithographic Techniques for Advanced Microfabrication

Advanced microfabrication relies on a suite of lithographic methods to etch or deposit features with ever-smaller dimensions and ever-tighter tolerances. Conventional optical lithography remains the backbone of high-volume chip production but is reaching its diffraction limit as feature sizes approach the deep sub-10 nm regime. Extreme ultraviolet lithography (EUVL) at 13.5 nm wavelength has been adopted to extend optical patterning into the single-digit nanometre range, demanding novel high-performance photoresists and precise mask engineering to manage line-edge roughness and stochastic defects. Electron beam lithography (EBL) and focused ion beam lithography provide maskless, direct-write versatility for prototype devices and research applications, albeit at lower throughput. Alternative approaches such as nanoimprint lithography and directed self-assembly harness mechanical imprinting or molecular organisation to achieve high resolution with reduced equipment cost, while resistless techniques exploit surface chemistry or photon-induced oxide growth to bypass conventional resist limitations. Across all methods, key performance metrics—resolution, sensitivity and feature fidelity—must be balanced to enable next-generation electronics, photonic devices, sensors and biomedical platforms. Continuous innovation in resist chemistry, exposure tools and pattern transfer processes underpins the global drive towards wafer-scale manufacturing of sub-5 nm structures and beyond.

Research from Nature Portfolio

Recent studies have comparatively evaluated photoresist performance at standard extreme ultraviolet and higher-energy “beyond EUV” wavelengths. Experimental characterisation of multiple resist classes revealed that inorganic, metal-oxide formulations exhibit superior sensitivity and lower line-edge roughness when exposed to shorter wavelengths, in contrast to traditional organic chemically amplified resists. By applying a unified performance metric, researchers quantified how the chemical composition and photon energy influence the trade-off between resolution and exposure dose. These insights underpin the rational design of novel resist materials optimised for sub-10 nm patterning and illuminate pathways to overcome stochastic defects as the semiconductor industry moves towards ever-higher photon energies for advanced device fabrication.

Lithographic Techniques for Advanced Microfabrication publication trend

The graph below shows the total number of articles in lithographic techniques for advanced microfabrication across all publications each year (not limited to Nature Index journals).

Technical terms

Line-edge roughness (LER): Variation of a pattern’s edge from its intended path, affecting device performance.
Extreme ultraviolet lithography (EUVL): Patterning technique using 13.5 nm wavelength light to achieve sub-20 nm features.
Electron beam lithography (EBL): Direct-write method employing a focused electron beam to define nanoscale structures.
Chemically amplified resist (CAR): Photoresist in which a single photon event triggers multiple chemical reactions, increasing sensitivity.
Nanoimprint lithography (NIL): Mechanical pattern transfer technique that imprints a mould into a resist layer to form high-resolution features.

References

1. Approaching Angstrom-Scale Resolution in Lithography Using Low-Molecular-Mass Resists (. ACS Nano (2024).
2. Resistless EUV lithography: Photon-induced oxide patterning on silicon. Science Advances (2023).
3. Beyond EUV lithography: a comparative study of efficient photoresists' performance. Scientific Reports (2015).
4. Evolution in Lithography Techniques: Microlithography to Nanolithography. Nanomaterials (2022).