Design to Deployment
The critical bridge between a design concept and confidently proceeding with physical implementation is the deployment of modeling and simulation to verify desired functionality. Mission-critical systems operating in harsh operating environments, e.g. space, require the capability to assess the impact of the environment on the function and reliability of the system. Historically, this has been accomplished through a design, fabricate, test, and redesign cycle, where the testing focused on the response of the circuit to environmental stimuli. However, this process has both a high financial and schedule impact that hampers the characterization and design of mission-critical components within the 12 to 18-month new technology node introduction cycle. Modeling and simulation advancements have reduced this design-test-redesign cycle in state-of-the-art commercial electronics design, where electrical reliability and performance over process, voltage, and temperature variation are critical.
Incorporation of Models
The incorporation of other environmental models into the commercial EDA flows for integrated circuit design would allow prediction, during the design cycle, of environment driven responses and failures prior to actual circuit fabrication. The Rel-Micro engineering team has decades of experience in developing methods to study and simulate the impact of radiation on integrated circuit devices used in mission-critical applications. The fundamental challenge, from a scientific perspective, is that radiation-matter interactions are very physical, localized events – often occurring on the nanometer scale; and IC circuit design occurs at a much higher level of abstraction – often at the level of pre-designed standard circuit cells that are automatically placed on an integrated circuit floorplan and wired together to perform the desired function.
While powerful tools exist to analyze radiation effects at the microscopic level, such tools are impractical at the EDA level due to the sheer scale of computational power required for simulation of just a few transistors. These tools are excellent for the study of radiation mechanisms and the elucidation of potential vulnerabilities at the transistor levels, but are impractical for integrated circuit design. On the other hand, modern simulations admirably reproduce circuit operation at the compact model level (e.g. SPICE) and higher levels (behavioral, Boolean), but do not capture the physical subtleties of a radiation interaction at nano-scale transistor geometries.
A Unique Approach
The Rel-Micro approach is unique. We are developing a “bottom-up” scientific approach; building on a legacy of scientific discovery and radiation modeling to “push” this information up the design hierarchy to enable predictive radiation-hardening-by-design (RHBD) analysis at the EDA level. This vertically-integrated, radiation-aware design (VIRAD) methodology is being integrated with industry standard design toll flows. VIRAD includes analysis capabilities to identify vulnerabilities at the schematic and topological levels to inform RHBD mitigation efforts prior to physical implementation. VIRAD also includes layout-aware analysis capabilities to inform device placement and critical-node spacing variants for identical schematic designs during circuit layout, as shown in the figures below.