Selectivity and cost control of etching process

Plasma etching may be the most important process in semiconductor manufacturing, or it may be the most complex wafer fab operation second only to photolithography. Almost half of the wafer manufacturing steps rely on plasma, a high-energy ionizing gas, to complete their work.

Despite the continuous shrinking of transistors and storage units, engineers continue to provide reliable etching processes.

Thomas Bondur, Vice President of Etching Product Group Marketing at Lam Research, said, "In order to sustainably manufacture chips with nanoscale precision and the correct structure, wafer fab equipment manufacturers need to break through the boundaries of plasma physics, material engineering, and data science and provide the necessary equipment solutions.". This is most evident in plasma etching, where plasma etching and photolithography work together to create precise and reproducible features on wafers.

This report investigates the key etching steps in 3D NAND, DRAM, nanosheet FET, and interconnect, and looks forward to 2D devices and backend processing. The industry is also pursuing more sustainable etching chemistry to reduce equivalent carbon dioxide emissions from its wafer fabs.

For many tool manufacturers, process modeling plays a crucial role in the development of etching processes. The goal is to shorten the time to market while reducing wafer and mask costs.

Barrett Finch, Senior Marketing Director at Lam Research, said, "Some of the most challenging steps of etching process optimization may take a year or more to complete.". "We have recently completed some process simulation work within three weeks, which is expected to take three months, using typical silicon-based testing and development."

In terms of the cost of masks and wafers for equipment manufacturers alone, this could reach hundreds of thousands or even millions of dollars.