Atomic layer etching brings ‘cutting-edge’ method to semiconductor nanofabrication

As its name suggests, atomic layer etching (ALE) involves a layer-by-layer cutting into materials on an atomic scale, and it has emerged as a promising method for semiconductor nanofabrication. In contrast to the more common reactive ion etching, which quickly removes material from computer chips through ion bombardment, ALE provides much more precision and uniformity.

There has been, however, a need for some fine-tuning as the technique is limited by low throughput and process complexity, among other issues.

Lee et al. assessed ALE from an industry perspective that looks at its current limitations — and its imminent potential in advanced patterning.

“Though academia has researched ALE, there are gaps in perspectives between [the research] and industry,” said author Keun Hee Bai. “And recognizing that the technique has had [a] few issues that have been a barrier to its widescale industry adoption, we also show those issues are being mitigated and will be cleared soon.”

Primarily, the issues have arisen as a result of the multi-step process sequencing ALE entails. But each issue, the perspective suggests, is not an independent problem but rather part of a collective challenge rooted in ALE’s complex cyclical nature. Careful process design and optimization, as well as architecture simplification, are expected to mitigate many of the issues.

Additionally, the researchers identified yet another advantage of ALE.

“Most studies have emphasized many advantages [of ALE] including low damage, high selectivity, and fine control,” said Bai. “We add to this list by reporting the advantage of a more vertical profile because ALE can create 90-degree angles with uniform widths into the layers.”

Source: “Current status of atomic layer etching and its adoption to low-k fine patterning: An industrial perspective,” by Sanghyun Lee, HyunWook Ra and, Keun Hee Bai, Journal of Vacuum Science & Technology A (2026). The article can be accessed at https://doi.org/10.1116/6.0005592 .

This paper is part of the Atomic Layer Etching (ALE) Collection, learn more here .