Dr. Stefan P. Hau-Riege

The ScienceDaily article Brightest, Sharpest, Fastest X-ray Holograms Yet said

The pinhole camera, a technique known since ancient times, has inspired a futuristic technology for lensless, three-dimensional imaging. Working at both the Advanced Light Source (ALS) at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory, and at FLASH, the free-electron laser in Hamburg, Germany, an international group of scientists has produced two of the brightest, sharpest x-ray holograms of microscopic objects ever made, thousands of times more efficiently than previous x-ray-holographic methods.
 
The x-ray hologram made at ALS beamline 9.0.1 was of Leonardo da Vinci’s famous drawing, “Vitruvian Man”, a lithographic reproduction less than two micrometers (millionths of a meter, or microns) square, etched with an electron-beam nanowriter. The hologram required a five-second exposure and had a resolution of 50 nanometers (billionths of a meter).
 
The other hologram, made at FLASH, was of a single bacterium, Spiroplasma milliferum, made at 150-nanometer resolution and computer-refined to 75 nanometers, but requiring an exposure to the beam of just 15 femtoseconds (quadrillionths of a second).

Stefan P. Hau-Riege, Ph.D. was one of the scientists creating these X-Ray holograms and is a physicist at LLNL, working on free-electron-laser interactions with materials in the context of LCLS. Previously he worked on Extreme-Ultraviolet Lithography and laser-assisted recrystallization.
 
Prior to joining LLNL in 2001, he was with Intel working on metallization reliability, and prior to that with AT&T Bell Laboratories. He earned his Ph.D. in Materials Science from Massachusetts Institute of Technology and a Masters in Solid-State Physics and Applied Mathematics from the University of Hamburg, Germany. He has published extensively in the areas of metallization, laser-material interaction, and diffractive imaging, holds several U.S. patents, and organized and taught UC Berkeley Extension courses for several years.
 
Stefan’s patents include Method of making a semiconductor device that has copper damascene interconnects with enhanced electromigration reliability, Method of doping a conductive layer near a via, Tamper to delay motion and decrease ionization of a sample during short pulse x-ray imaging, Method for characterizing mask defects using image reconstruction from X-ray diffraction patterns, Electromigration-reliability improvement of dual damascene interconnects, Direct-patterned optical waveguides on amorphous silicon films, Wafer-bonding using solder and method of making the same, and Structure, system, and method for assessing electromigration permeability of layer material within interconnect.
 
He authored Probabilistic immortality of Cu damascene interconnects and coauthored Femtosecond Diffractive Imaging with a Soft-X-ray Free-Electron Laser, In situ transmission electron microscope studies of the kinetics of abnormal grain growth in electroplated copper films, The effects of the mechanical properties of the confinement material on electromigration in metallic interconnects, Femtosecond time-delay X-ray holography, Electromigration saturation in a simple interconnect tree, Subnanometer-Scale Measurements of the Interaction of Ultrafast Soft X-Ray Free-Electron-Laser Pulses with Matter, and Dynamics of biological molecules irradiated by short x-ray pulses.