Scientists look to reduce cost of microchips through plasma
Scientists at the US Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) are developing computer simulation codes to boost microchip production through the use of plasma – an electrically charged state of matter pivotal in fusion research.
These advancements promise to enhance the efficiency of the manufacturing process and might well spark a revival of the chip industry within the US.
Igor Kaganovich, a principal research physicist at PPPL, emphasised the importance of microchips in national security, stating: “Because devices with microchips are essential to our daily lives, how and where they are made is a matter of national security. Robust and reliable simulation tools that can accurately predict plasma behaviour and shorten the manufacturing and design cycle of silicon chips could help the US regain a leadership role in this field and maintain it for decades.”
The initiative to accelerate development is evident in one of PPPL’s projects aimed at diminishing the computational time required for simulating microchip plasma reactors. This breakthrough is anticipated to empower the industry with more intricate and precise simulations, thus propelling efforts to reduce microchip production costs.
Andrew Tasman Powis, co-author of a key study and a computational research associate at PPPL, highlighted the challenge: “Companies would like to use simulations to improve their processes, but they typically are computationally expensive. We are doing our best to counter this trend.”
The drive for accuracy in simulations leads to the creation of virtual depictions that capture the detailed dynamics of plasma, necessitating sophisticated algorithms and substantial computational resources. Researchers, however, revisited historical plasma physics to unearth algorithms from the 1980s that could offer a shortcut in simulating microchip plasma, managing to retain considerable accuracy while significantly reducing simulation times.
Haomin Sun, the study’s lead researcher, pointed out the practical benefits of this approach, saying: “This development is important because it could save companies both time and money. That means that with the same amount of computational resources, you can create more simulations. More simulations not only allow you to find ways to improve manufacturing but also to learn more physics in general. We can make more discoveries using our limited resources.”
Further reinforcing these advancements, Powis’s subsequent research demonstrated that computer codes can indeed model plasma particles effectively in larger virtual spaces, hence reducing the computational demand. “This is good news because reducing the number of cells could lower the computational cost of the simulation and, therefore, improve performance,” Powis remarked.
The algorithms are particularly aimed at simulating ‘capacitively coupled plasma reactors’, crucial for etching intricate microcircuitry into silicon wafers, thereby enabling microchip functionality. Powis expressed the goal of understanding and controlling plasma properties to refine the etching process.
The research team is also exploring solutions to inherent simulation errors, addressing the limitations of current methods that approximate the behaviour of plasma particles. Sierra Jubin, a leading researcher, stressed the significance of overcoming these inaccuracies for realistic simulations, stating: “This is a problem because if we don’t address this issue, we won’t be modelling the phenomena as they actually occur in the world.”
This collection of research efforts, supported by PPPL’s laboratory-directed research and development program and conducted in collaboration with international and national institutions, marks a significant step towards revolutionising microchip production simulations. With contributions from a diverse team of researchers across the globe, these advancements herald a new era in the field, underpinned by PPPL’s pioneering work and the potential for transformative impacts on the chip manufacturing industry.