New-Tech Europe Magazine | May 2018

Customized cybersecurity: encrypting unique codes on chips with maskless lithography

Laurent Pain, Isabelle Servin, CEA-Leti

Leti, a French research institute at CEA Tech, and Mapper Lithography BV, the leading provider of maskless direct-write lithography equipment for the semiconductor industry, recently announced a low-cost cybersecurity breakthrough that allows encrypting unique codes directly on individual chips. This technology provides a novel way to secure private information, devices, business exchanges, cloud data, etc., in the massive data exchanges enabled by the Internet of Things (IoT). Several technological solutions, such as software or fuse or physical unclonable function (PUF) strategy, are available, but present their own safety limitations. Indeed, none of these solutions can directly and deeply spread security codes into the hard IP core of the devices, as this direct write solution significantly enhances anti-piracy

efficiency in the final product. The encryption approach offered by maskless lithography opens a new technology era in the field of cyber- security. Mapper Lithography has introduced its first pilot R&D platform, the FLX–1200 platform, which is initially designed to reach throughput of one 300mm wafer per hour (wph) for a wide range of technologies, from mature nodes down to 28nm. The FLX-1200 exposure tool is based on massively parallel electron beam direct-writing (MP EBDW) strategy, using simultaneously 65,000 low- power individually controllable electron beamlets, each writing its own part of the IC design. The wafer is exposed one column of fields at a time and always in the same direction. While the wafer is moved under the column, each beamlet is deflected at a high

frequency perpendicular to the scan direction. The deflection range is around 2µm. Each column of fields is aligned separately, by scanning dedicated alignment targets to calibrate the exact position of the wafer with respect to the beamlets (Figure 1). Mapper’s technology scales by clustering several exposed units connected to a resist process track. That forms a litho cell working at the same performance level with higher throughput capability. Photomask free This lithography solution is based on the direct-write concept, and therefore no photomask is required to directly pattern the chip design onto the wafer. The use of massively parallel electron- beam writing allows reaching high-throughput benefit compared to current single- electron-beam systems (1wph

20 l New-Tech Magazine Europe