Radiation hardened SRAM withstands 15 Mrad total ionization dose

The developed technology opens multi-billion markets that require specific components able to withstand high dose radiation. Such doses lead to errors and irreversible failures in standard CMOS products. The markets include electronics for communication, observation and navigation systems as well as new applications, such as production of medical devices sterilized with high doses of gamma radiation and further tracking of these devices. As a part of the Program focused on the development of the radiation hard components, the companies for the first time report the results of testing RedCat’s 512 kbit SRAM (RC7C512RHH). The part has been designed by RedCat using its rad-hard standard cell library and IPs with the support of TowerJazz’s Design Center in Netania, Israel, and fabricated in TowerJazz’s Fab 2 in Migdal Haemek, Israel utilizing a flavor of its commercial 0.18-micron CMOS process flow. RC7C512RHH has been developed following several rad-hard by design techniques: from the architecture level down to the layout level. Edge-less transistors were used to avoid Total Ionization Dose (TID) damaging effects. Transient propagation and functional interrupts as well as single-event latch-ups were mitigated by patented design solutions. SRAM was supplied with rad- hard pad ring (ESD protection). The experiments were performed at the X-ray facility in Legnaro (Padova), Italy in passive and active modes. No errors were observed for absorbed doses of above 15 Mrad (Si). All of the functional tests after irradiation passed without any failure. Radiation immunity of the demonstrated level was previously reported only for digital ICs fabricated in dedicated foundries specialized in rad-hard technologies. Therefore, this new design allows for radiation immunity on analog ICs fabricated using TowerJazz’s CMOS process. “We are impressed by the design demonstrated by RedCat, which in combination with TowerJazz’s CMOS technology allowed us to achieve outstanding SRAM performance. By making rad-hard technology available in TowerJazz’s commercial foundry, it allows us to not only target the traditional aerospace applications, but also the growing multi-billion dollar markets of food processing, medical device sterilization, and environmental cleanup technologies,” said Dr. Avi Strum, TowerJazz VP and General Manager of Specialty Business Unit. "We are excited about producing specialty rad-hard ICs in cooperation with TowerJazz,” said Dr. Cristiano Calligaro, CEO of RedCat Devices. “Many customers have already expressed their interest in the developed technology. We plan to expand and diversify our rad-hard product portfolio to include non-volatile memories and CMOS image sensors, and we are pleased that TowerJazz offers these specialty process technologies as well. Some of the products are already in the final stages of development.”