Joanna Maria Vandenberg is a Dutch solid statechemist and crystallographer who immigrated to the United States in 1968. At Bell Telephone Laboratories, she made a major contribution to the success of the Internet. She invented, developed, and applied the X-ray scanning tool for quality control essential to manufacturing indium gallium arsenide phosphide-based multi-quantum well lasers. These are the lasers that amplify and modulate light that travels through optical fibers that are at the heart of today's Internet.
Early life
Joanna Vandenberg was born January 24, 1938 in Heemstede, a small town near Amsterdam, where she was the youngest of a family of five, and the first one to go to college. Her family was in the tulip business. In 1956 she graduated Cum Laude from gymnasium-β and went to the State University of Leiden in the Netherlands where she received a B.S. in Physical Sciences and Mathematics, 1959 and a M.S. in Inorganic and Solid State Chemistry with A. E. van Arkel as well as Theoretical Chemistry, 1962. She studied with van Arkel in Leiden and Caroline H. MacGillavry in Amsterdam for a Ph.D. thesis on X-ray diffraction analysis of metal–metal bonding in inorganic compounds, 1964.
Career
She worked for 4 years at Royal Dutch Shell laboratory in Amsterdam, where she joined the research group on catalytic properties of transition metal-layered chalcogenides. In 1968 she moved to Bell Laboratories where she continued work on structural and magnetic properties of transition-metal chalcogenides. Her career was interrupted when she was laid off seven months into her first pregnancy. She was rehired in 1972 after the AT&T operators won a historic class action lawsuit for being fired when pregnant. With Bernd Matthias of UCSD, she started to work on metal cluster formation in superconducting ternary transition metal compounds. Her extensive knowledge of structural inorganic chemistry enabled her to predict inorganic crystal structures and led to the discovery the superconducting rare earth ternary borides. In 1980 she changed direction and began research on contact metallization on InGaAsP/InP multi-quantum well layers used as high speed digital lasers in the internet. She designed a temperature-dependent in-situ annealingX-ray diffractometer. This technique made it possible to optimize the electrical behavior of the gold metallization contacts and became a standard reference in semiconductor industry. In 1986 Vandenberg turned her attention to the quality control of the crystal growth of InGaAsP multi-quantum well layers, used as laserlight sources and optical modulators designed to work in the 1.3 to 1.55 μm wavelength range. Advancing the design, performance and manufacturability of these devices had been the focus of all the leading optical component suppliers for decades. These devices are manufactured using organometallic vapor phase epitaxy, a complex process involving multiple sources subject to drift. Manufacture of early devices was based on unacceptably low end-to-end yields. Dramatic improvement was needed to produce the high performance components used to transport the massive amounts of data in today's Internet. In many cases mono-layer thickness control is required along with variations in bandgap less than 0.5%. This high level of quality control must be achieved using complex crystal growth machines which can fail in hundreds of ways. To insure that these multiple failure modes do not impact the final device, Vandenberg designed a one-room non-destructive high-resolution X-ray diffractometer to provide immediate on-line feedback into the MQW growth process. She constructed robust algorithms linking X-ray features to layer thickness and strain information essential to crystal growth control and optoelectronic device performance. Her X-ray diffraction technique is used to scan every laser wafer many times during manufacture. All Internet lasers are now manufactured using her tool X-Ray Crystallography, and their operational lifetime exceeds 25 years.