A cutting-edge semiconductor industry or techscape is now seeing chip features being shrunk smaller than the dimensions measured in mere atoms. Such a leap requires advanced patterning, which is a vital process involving high-precision lithography, deposition, and etching techniques working together to scale devices beyond the scope of conventional methods.
These advanced patterning processes will be used in future logic, DRAM, and NAND devices to cram more transistors into smaller dies thereby leading to faster speed, lower power consumption, and enriched functionality. Through the means of advanced patterning, one further increases yields, minimizes defects, and cuts costs at sub-half-micron nodes.
Why Does Advanced Patterning Matter?
Advanced patterning unlike the conventional method was made to help pass resolution limits that come with conventional photolithography. It can provide enhanced layouts as well as finer controls such that the application of Moore’s Law can continue with great force by semiconductor manufacturers.
Benefits include:
- Higher performance and density: More functionality in smaller chip areas.
- Improved yields: Larger process windows reduce defects.
- Sustainability: Advanced processes deliver better energy and cost efficiency.
Patterning Techniques in Action
Single Patterning versus Multipatterning
Single Patterning has been the simplest and most cost-effective method, but this only applies when the scanner is able to resolve the smallest features.
Multi-Patterning (be it Double, Triple, or Quadruple) pushes resolution limits by applying multiple exposures and photomasks. Cases of such techniques are Litho-Etch-Litho-Etch (LELE) and Litho-Freeze-Litho-Etch (LFLE) for creating feature sizes required by very dense chip designs.
Self-Aligned Patterning
Self-aligned processes, including SADP, SAQP, and SALELE, use sidewall spacers or etched references to define features smaller than those that can be lithographically defined while improving placement accuracy and pattern fidelity.
EUV Lithography
Next is Extreme Ultraviolet lithography with the shortest wavelength of 13.56 nm. EUV can produce sub-10-nm features required for nodes like 7 nm, 5 nm, etc., while resisting challenges are still there in things like resist sensitivity, defect control, and edge placement error (EPE).
Step Over the Patterning Challenges
As chips scale toward 3 nm and smaller, tolerances go down to just a few atoms. Controlling EPE caused by stochastic photoresist defects, photon limitations, and scanner imperfections is one of the biggest hurdles. Even a single misplaced edge can lead to yield loss in wafers containing billions of transistors.
Lam Research enables advanced logic and memory scaling through a suite of precision patterning technologies, including Akara for ultra-accurate etching, VECTOR DT for wafer flatness enhancement, Corvus for vertical ion edge control, Kyber for cost-effective line edge roughness reduction, and Aether for efficient dry EUV photoresist processing.
The Road Ahead
As the semiconductor roadmap pushes toward the angstrom era, advanced patterning is no longer optional it is the foundation of innovation. With companies like Lam Research leading the charge, the industry is unlocking the ability to build smaller, faster, and more sustainable chips that will power AI, advanced computing, and next-generation devices.
(This article has been adapted and modified from content on Lam Research.)