It just so happens that this phenomena is present when inspecting silicon (E) and gallium arsenide (GaAs) – two of the most important materials in the printed circuit board (PCB) and integrated circuit (IC) production industry.

LED SWIR wavelengths have high-level transmittance through silicon beginning at around 1050 nm. Following this discovery and the apparent ability to look through silicon-based matter has given rise to the development of highly accurate defect inspection systems.

A powerful tool in the detection of many different types of defect, SWIR LEDs and microscopic imaging allows proper analysis to find the cause. Many circuit failures can be attributed to a broken or open circuit. The culprits of such failures are as diverse as metal impurities in the substrate, electrical overstress (EOS), or misaligned masking during the photolithography process.

While many defects may immediately render the layered IC useless, others may only become apparent once in the hands of the end-user. The ability to find and identify these problems can reveal issues in the production process. This can prevent serious financial losses and production downtime for manufacturers, as well as avoiding the recall of potentially all devices produced during the period that the defect manifested.