Fraunhofer Institute for Electronic Microsystems and Solid State Technologies EMFTIn the semiconductor industry, climate-impacting substances and gases play a crucial role, particularly fluorinated specialty gases like C2F6, NF3 und SF6, which have a high greenhouse gas potential. These gases are used in dry etching during wafer fabrication or for cleaning deposition process residues in process chambers. Despite their significant greenhouse gas potential, little is known about their contribution to the global greenhouse effect, as the emitted quantities are very small compared to the well-known climate gases carbon dioxide and methane. To address this knowledge gap, the Fraunhofer Gesellschaft has launched the project "Climate-Impacting Gases and Substances." This project involves several Fraunhofer institutes and aims to capture and assess the emissions of these gases. This will allow for an analysis of their impact on global warming and the development of measures for reduction.
Climate relevant process gases and their influence on the greenhouse gas effect
Effective measures to reduce emissions in the semiconductor industry
With the EU Chips Act initiative aimed at strengthening semiconductor manufacturing in Europe, emissions of these specialty gases could increase significantly in the coming years, thereby contributing to the European greenhouse gas balance. To counteract these developments, emission reduction measures are essential. These include not only the optimization of process management but also downstream cleaning systems (abatement). However, these systems require a substantial amount of energy to break down the chemically stable process gases so that they can be washed out of the exhaust or chemically bound.
Aim of the project
The inter-institute project "Climate-Impacting Gases and Substances," funded by the Fraunhofer Climate Fund, aims to develop tools for capturing and assessing the emissions of fluorinated specialty gases from the Fraunhofer Gesellschaft in terms of their greenhouse gas effect. Furthermore, the project seeks to raise broader awareness of the potential contribution of fluorinated process gases to global warming and to highlight possible solutions for minimizing emissions.
Implementation and Analysis
As part of the project, both hardware and software will be implemented to read the gas flow from mass flow controllers to process equipment and to accurately capture and log the consumption of climate gases in a process-specific manner. This can be used, for example, to optimize semiconductor processes for low gas consumption.
Various gas analysis systems will be employed to monitor the consumption of fluorinated process gases online under reaction conditions in the process chamber. These data represent another component in reducing emissions of fluorinated greenhouse gases.
To assess the efficiency of downstream abatement systems, the proportion of fluorinated process gas in the total exhaust flow will be measured before and after the process chamber. Different analytical techniques, such as mass spectrometry and FTIR spectroscopy, will be used. These methods are necessary to account for the significant dilution of the exhaust flow due to the nitrogen ballast from the vacuum pumps and the supplied combustion gases in the abatement system.
The analysis of the various methods and their results will provide important insights into the effectiveness of emission reduction measures and contribute to a better understanding of the role of fluorinated gases in global warming.