Open-IRIS: Low Cost, Fully Open Source In-situ Infrared Inspection of Silicon

Abstract

Short-Wave Infrared (SWIR) imaging has become a powerful and well-known technique over the last two decades for silicon inspection and imaging. Open-IRIS is a low-cost, fully open-source system for in-situ InfraRed Inspection of Silicon devices (IRIS). It is designed to lower the cost barrier for academic and research users requiring high-precision IR imaging of silicon microelectronics. This thesis details the design and implementation of the Open-IRIS platform, including its optomechanical components, motion control system, electrical system and software architecture. Its design is highly modular and low cost, making it an invaluable and extensible tool for many future applications, including microarchitectural security research, chip failure analysis, and biological imaging. Key design challenges, such as achieving high mechanical and optical resolution on a budget are addressed. Computational microscopy techniques, including Fourier Ptychographic Microscopy (FPM), are evaluated to improve resolution. The system’s imaging resolution on a standard resolution target is evaluated, as well as its motion repeatability and accuracy.

Results show that Open-IRIS achieves 5.34 μm optical resolution with a 5x objective, and 3.47 μm resolution with a 20x objective. Mechanically, it has 6.5 μm repeatability, and 35.5 μm accuracy, all on a total budget of less then US$1000 - a fraction of the cost of comparable commercial systems. The complete design is fully open-source, enabling broader access to advanced chip inspection techniques, and serves as an excellent starting point for future expansion into advanced security research like laser fault injection.