Reflections on SEMICON West: Advancing RF-SOI Technology

Published: July 11, 2024

Reflections on SEMICON West: Advancing RF-SOI Technology

By: Scott Bibaud, President and Chief Executive Officer, Board Director, Atomera

At SEMICON West this week, one of the best sessions was a series of TechTALKS on “Material Innovations for Advancing Design Optimization.” It was kicked off by Dave Thompson of Intel who talked about the challenges the industry will experience in the future with evolving transistor architectures and how new material solutions from many players within the semiconductor ecosystem will be required to continue advancing Moore’s law. Later we had several presentations dealing specifically with RF-SOI, clearly illustrating how difficult it is to find improvements in this tricky corner of the RF design world.

The SOI market is a large and growing segment. In 2022 it had sales of $1.4B and is projected to continue growing at a 15% CAGR into the future to the point where some projections put the market size at $10B in 2034. RF-SOI makes up the majority of SOI revenue today because of the strong adoption in 5G cellular front ends. Atomera works with the majority of consumers of RF-SOI wafers for RF applications, and we believe we can help them drive the projected growth of this industry.

The application of MST technology in RF-SOI is intended to solve a well understood, but very difficult to solve problem among designers. To optimize performance on an RF-SOI based RF switch, designers try to minimize the product of Ron and Coff without compromising the maximum power it can withstand. It has been well understood that Coff can be improved by minimizing the thickness of the SOI silicon, but this degrades the power handling capability. Atomera breaks this trade-off by using MST on thin RF-SOI substrates to mitigate electron and hole flow issues which cause the power handling problems.

Before Soitec offered the thinner substrates, customers would have to go through a process of thinning the wafers themselves before MST could be applied, which introduced additional cost, complexity and potential defects. Our customers specifically asked us to address this issue and streamline the supply chain. Now there are multiple ways that MST can be deposited on wafers for customers going to production. MST-enhanced thin RF-SOI wafers could be supplied by a wafer manufacturer, deposited by the foundry making the devices, or implemented directly by an IDM. Pre-production customers can get sample quantities of these wafers from Atomera.

By demonstrating the benefits of our technology on Soitec’s thin RF-SOI wafers, we will be helping customers to adopt faster and feel more comfortable about a solution for production volumes. Of course, this is why response to our new MST solution for RF-SOI wafers as announced in our press release last week has been so positive.

Atomera’s RF-SOI solution is a great example of how materials like MST are instrumental in continuing to advance the industry.