World Record Set by 4nm 3D Chip X-ray Technology

Researchers in Switzerland have made a significant breakthrough in the field of X-ray imaging, achieving a record resolution of 4nm for a 3D X-ray of an AMD CPU. The team at Paul Scherrer Institute (PSI) utilized X-rays from the Swiss Light Source SLS at PSI, employing a technique called ptychography to create a single, high-resolution picture by combining many individual images.

The collaboration involved EPFL Lausanne, ETH Zurich, and the University of Southern California, focusing on X-ray images with shorter exposure times and an optimized algorithm. While scanning electron microscopes are effective for imaging tiny transistors and metal interconnects in circuits, they are limited to producing two-dimensional surface images.

According to Mirko Holler, a physicist at SLS, "The electrons don’t travel far enough into the material to construct three-dimensional images with this technique. To achieve this, the chip must be examined layer by layer, removing individual layers at the nanometer level, a complex and delicate process that also destroys the chip."

However, X-ray tomography allows for the production of three-dimensional and non-destructive images as X-rays can penetrate materials more effectively. This process, similar to a CT scan in a hospital, involves rotating the sample and X-raying it from various angles to reconstruct a final 3D image using an algorithm.

The sample used in the study was an extract from a commercial AMD processor, supported by a gold-colored pin in the center of the picture. Measuring less than 0.000005 meters in diameter, it was cut from the chip using a focused ion beam and placed on the pin for imaging.