Semiconductor Material Sustainability
Many materials in conventional semiconductor devices come from environmentally damaging extraction processes, are high-risk pollutants, and/or pose severe human health hazards. At the same time, the ever-growing demand for speed, large memory, and long battery life are the performance metrics that dictate achieving next-generation electronics. The long-term environmental impacts are obscured and neglected. Researchers at the Singapore University of Technology and Design (SUTD) are trying to change that.
The research team proposed a unifying framework that identifies low-risk materials for development. Their identification focus is: (1) How plentiful are the raw ingredients? (2) How can we obtain them? (3) What is their fate at the end of their operational lifetime? The team is collaborating with researchers from the United States, China, and Malaysia, and their findings were published in a paper: ‘Toward sustainable ultrawide bandgap van der Waals materials: An ab initio screening effort,’ in Advanced Functional Materials.
Their work focused on state-of-the-art computational methods used to supplement the field of nanostructures and ultrathin 2D materials. Simulation-informed computational screening is a popular accessory in accelerating the formulation of 2D materials. This approach shortlists candidate materials for precise experimental prototyping efforts. Seldom, however, are environmentally safe options considered as enforcing sustainability-driven screening criteria could substantially reduce the number of available strong contenders for specific applications and lead to poor product performance.
The team published an analysis of possible constituent materials available for the sustainable design of ultrawide bandgap (UWBG) semiconductors. They are used in transistors found in computers and smartphones, electronics in vehicles, and UV sensors in fire detectors and healthcare technologies, to name a few. Stringent constraints on the search for ideal materials included those that did not pose environmental risks, were non-hazardous to human health, and were in no danger of depletion. They also must meet such key requirements for serving as UWBG semiconductors as suitability for low-power standby operation, mechanical robustness, and performance as UV detectors.
From an original 3,000 entries in the materials database, the search algorithm sieved out a mere 25 remaining candidates found to exhibit high performance over a broad range of applications. The findings show that sustainability-driven research is possible and able to achieve a balance between performance and sustainability.
