By Vivek Bakshi, EUV Litho, Inc.
The technology of EUVL, coupled with its economic impact, are indeed complex and evolving. On the eve of EUVL’s deployment in high-volume manufacturing, we need to understand both technology and economics. Moore’s Law puts an additional time constrain on readiness for a manufacturing node, which a technology must meet. Ultimately it is the economics that will decide EUVL’s long-term future, but it is very much coupled with technology and how it will evolve for future nodes. Here, I will describe these aspects briefly to give you an overview of what has been called an “epic challenge for advanced semiconductor manufacturing.”
To understand EUVL technology, one needs to know about not only scanner, but also about light sources, optics, contamination, materials, mask metrology and resist. All of these components of EUVL are different than those for 193 immersion multipatterning (193i MP) – although both are part of optical projection lithography. In terms of technical issues, which can slow down implementation at the 7 nm node, the only open issue now is scanner uptime. Higher tool uptime (goal of 90%) will improve throughput and hence cost of ownership. But there is lot more to be done at future nodes. In order to understand future challenges for source, mask, resist and patterning and manufacturing, it is not only important to understand each component itself but also how each component affects the others in the overall manufacturing flow. Some new knowledge is required here that we can gain from a new text, EUV Lithography (2nd edition, SPIE Press, February 2018), that I have edited for SPIE press, with contributions from technology leaders. In this second edition of the book, I would like to highlight some new chapters containing key technical knowledge. These include chapters on optics by Carl Zeiss, maker of optics for the EUVL scanner; on EUVL scanner by ASML; and several chapters on EUV sources. Chapters on mask, resist and patterning will also give you the necessary knowledge to understand the technology.
Economics of EUVL
For many of us, when we want to know how quickly and how widely EUVL will be implemented, we really are asking how this new technology is going to impact the present infrastructure of 193i MP. To understand this, we need to know when chipmakers will use EUVL and how they will use it in a given type of product. Logic will be probably the first, followed by memory. Contacts and vias will be first followed by metal lines and then gates. Volume of adoption will depend on market timings as well as perceived readiness of a chipmaker by their internal or external customers. Leaders in EUVL are GlobalFoundries, Intel, TSMC and Samsung, with a few others very keenly interested. However, some leaders will sacrifice their bottom-line to be first to capture the high-end business and get ahead on the learning curve to improve yield. It is a good bet, in my opinion.
Another big question is that how adoption of EUVL will affect the number of additional tools needed for etch, deposition and metrology, which support 193i MP. Of course, we will need fewer of them, as EUVL slowly replaces it. But how much and how quickly is a more complex topic. Questions to ponder include: How significant are the challenges for EUVL in the future? Will they slow down the timing and magnitude of EUVL’s implementation in 7 nm and future nodes? Finally, a group of companies and innovators want to know if their technology, products and ideas have a place in the EUVL infrastructure and if so, how big is the market. These are deep questions and require a lot of technical and economic information to form an educated opinion.
Let us discuss this epic technical and economic challenge.
Together with my colleagues, I plan to spend an entire day going over all these topics at the EUVL short course during the 2018 EUVL Workshop. A day is not really enough, but I expect it to be a fruitful endeavor. For most of the day, we will use new EUVL edition as the textbook for the short course to get the latest on fundamentals. I will then wrap up with a discussion of economic aspects. If these topics are of interest to you, I hope you will join us. Please visit www.euvlitho.com for further details.