Researchers use lasers and metalenses to align 3D chips with atomic precision

Forward-looking: Researchers at the University of Massachusetts Amherst have developed a laser-based technique to align 3D semiconductor chips, potentially overcoming a longstanding challenge in chip manufacturing. The method employs concentric metalenses to generate holograms that reveal misalignment between chip layers at a much smaller scale than previously possible. Semiconductor chips have traditionally been manufactured in two dimensions. But as devices become more powerful and compact, the industry is increasingly turning to 3D chip designs, which involve stacking multiple 2D layers. This approach introduces significant technical challenges – most notably, the need to align each layer with extreme precision. Even slight misalignment can compromise chip performance. The traditional approach for aligning two layers is to look with a microscope for marks, such as corners or crosshairs, on the two layers and to try to overlap them, said Amir Arbabi, associate professor of electric ... Read full article.