Since its launch, HaloFreeEtch has made significant progress toward its goal of enabling halogen-free, sustainable plasma etching processes for the semiconductor industry. The project’s first results demonstrate the feasibility of combining advanced modeling, experimental validation, and sustainability assessment into a single, integrated development framework.

computational screening & novel chemistries

Advancing Halogen-Free Etching Technologies

A major scientific outcome of HaloFreeEtch is the creation of a comprehensive database of halogen-free etchants, developed through advanced quantum chemical (DFT-based) computational screening. This approach allowed the consortium to evaluate the stability and reactivity of numerous candidate molecules and to identify a first set of promising halogen-free etching chemistries for further laboratory validation.

By integrating computational screening with process and plasma modeling, the project is significantly reducing experimental trial-and-error, accelerating the identification of viable alternatives to conventional halogen-based etching processes.

HaloFreeEtch has established a multi-scale modeling framework that links plasma chemistry, reactor-scale process behavior, and equipment-specific conditions. This framework has already been successfully applied to:

  • Sulfur hexafluoride (SF₆) plasma etching, serving as a validated reference process.

  • A novel halogen-free etching chemistry, which shows lower etching yields compared to SF₆ but provides clear directions for future optimization.

The modeling framework is designed to be extensible, allowing new chemistries and reactor geometries to be incorporated as kinetic data become available. This represents a key step beyond the state of the art and supports data-driven, sustainability-oriented process development.

integrated plasma, process & reactor modeling

Multi-Scale Modeling for Sustainable Process Design

surface interactions & catalyst-assisted pathways

Experimental Validation and Catalyst-Based Etching

On the experimental side, first-year laboratory work focused on exploring catalyst-assisted silicon etching as a potential route toward halogen-free processes. Preliminary investigations included:

  • The use of nanoparticles and nanostructured catalysts to promote dissociative adsorption of etchants on silicon surfaces.

  • Detailed studies on metal-assisted plasma etching (MAPE), building on promising results reported in scientific literature.

These foundational experiments establish the basis for future process optimization and scale-up activities planned in the next project phases.

To ensure that technological innovation goes hand in hand with environmental responsibility, HaloFreeEtch has already completed a baseline Life Cycle Assessment (LCA) for a conventional halogen-based reference etching process. Using data from real etching equipment and literature sources, the consortium developed a robust life cycle inventory despite challenges in data availability.

In parallel, a quick-LCA tool has been developed to directly translate etching recipes into environmental impact assessments. This tool will be used to perform prospective LCAs of halogen-free etching processes as they mature, enabling direct comparison between conventional and innovative approaches.

environmental metrics for process innovation

Life Cycle Assessment and Sustainability Analysis

data-driven frameworks for greener production

Building a Blueprint for Sustainable Electronics Manufacturing

Beyond individual technical achievements, HaloFreeEtch is establishing a novel, sustainability-driven process development scheme. By systematically integrating modeling, experimentation, and life cycle analysis, the project aims to provide a replicable blueprint for sustainable process development—not only in semiconductor manufacturing, but also in other technology-intensive industries.

Next Steps

Experimental validation of selected etchants, optimization of plasma parameters, and integration of sustainability metrics into process development.

Together, these results position HaloFreeEtch at the forefront of research on responsible and sustainable electronics, supporting Europe’s long-term competitiveness in the global semiconductor landscape.