Executive CommitteeCareer OpportunitiesMembershipHistoryPublicationsAACG AwardsManasevit Award
ACCGE-23 / OMVPE-21ScholarshipPast ConferencesAACG 50th Anniversary ContactAACGE West 2022

American Association for Crystal Growth
News - 2022
Many congratulations to Dr. James De Yoreo, Battelle Fellow, Physical Sciences Division, PNNL and Affiliate Professor of Chemistry and Materials Science & Engineering, University of Washington, who has been elected to the National Academy of Engineers for his contributions and advances in materials synthesis, from nucleation to large-scale crystal growth. He has been an active member of the AACG for many years and is currently a member of the Executive Committee.

He is joining the illustrious group of crystal growers and AACG members who have been elected to the National Academy of Engineers. The list includes Robert Laudise (1980), Alfred Y. Cho (1985), Morton Panish (1986), Don W. Shaw (1988), Russell Dupuis (1989), Robert A. Brown (1991), Martin Glicksman (1996), Gerald B. Stringfellow (2001), Shuji Nakamura (2003), Paul Daniel Dapkus (2004), Kenneth Jackson (2005), Thomas F. Kuech (2010), Gregory H. Olsen (2010), Darrell G. Schlom (2017), Christine A. Wang (2019), and James De Yoreo (2022).

We are sad to inform the Crystal Growth community that Professor Kenneth A. Jackson passed away January 7, 2022. Ken’s life was shining example of great curiosity, enhanced by a brilliant scientific mind and amazing diligence in his continuous quest for excellence in scientific research. 

Professor Jackson obtained his B.Sc degree in 1952 and M.Sc. degree in 1953 at the University of Toronto, Canada. After receiving his Ph.D. degree from Harvard University in 1956 he became an assistant Professor there. In 1962 he joined AT&T Bell Laboratories as head of the Materials Physics Research Group. In 1989 he become a Professor of Materials Science and Engineering and of Optical Sciences at University of Arizona, where he retired and became Emeritus in 2004. 

Ken contributed many outstanding discoveries that have affected the entire area of crystal growth. His major scientific interests were the kinetic processes of crystal growth, the molecular theory of crystal growth, thin film growth and characterization, ion beam processes and semiconductor processing. His scientific contributions include constitutional supercooling, which laid the foundation for the field of shape stability of crystals during growth, the surface roughening transition, defect formation in crystals, and studies of alloy crystallization. He also pioneered computer simulation studies of atomic scale processes during crystal growth. Ken rationalized the crystallization behavior of inorganic and organic compounds in terms of the dimensionless entropy of melting, ΔSm/R, which is used as a scale for the ease of crystallization. Also related to ΔSm/R is the Jackson "alpha factor" that determines the surface roughening of growth fronts. Ken’s 1974 short film from the AT&T archives on “Crystal Growth Morphologies” can be seen on YouTube https://www.youtube.com/watch?v=Y3GwvN5W1dE.

In addition to his contribution to the development of new ideas, Professor Jackson was active in teaching, mentoring and dissemination of scientific knowledge through international lectures, schools and conferences. He leaves a rich legacy in his scientific family tree. 
Ken was a member of the United States National Academy of Engineering. He served as founding Co-President (with Bob Laudise) of the American Association for Crystal Growth (AACG) and was also President of the Materials Research Society (MRS). He was part of the organizing committee of the first ICCG in Boston. He won the IOCG Frank Prize at ICCG-XII in Jerusalem in 1998. In 2003, he received the Bruce Chalmers Award from the Materials Processing & Manufacturing Division of the Minerals, Metals & Materials Society. He has received many other honors and awards and has published more than 145 papers. He also has edited ten books and holds four patents. Ken’s book Kinetic Processes: Crystal Growth, Diffusion, and Phase Transformations in Materials is widely used within the crystal growth community.

Ken was an individual who always lived life to the fullest. Those who knew Ken well know he was also a deep connoisseur of food and wine. He loved Arizona because he could eat dinner outdoors almost every day of the year.

We join his family and all his friends worldwide in grief but also in celebrating a life well lived and remembering our friend and colleague Ken for the kind of person he was. The crystal growth community and the world are better for his being a part of it.

We regret to report that on February 22, 2022, Professor Emeritus Bill Tiller, formerly of Stanford University passed away, he was 92 years old. He and Ken Jackson, who passed away just 6 weeks before (as reported on our website), were college students together in Toronto, Canada. In 1953, together with their advisor Prof. Bruce Chalmers and J.W. Rutter, they published in the new journal Acta Metallurgica, a very important article on solute redistribution during solidification, and the concept of constitutional supercooling. They derived an equation describing the relationship between growth rate, temperature gradients and material parameters. As the paper explained, when an alloy solidifies, the solute atoms that are rejected from the growing crystal are not uniformly distributed in the surrounding melt, but instead are concentrated near the crystal-melt interface because the diffusion of the solute in the melt is limited. The high concentration of solute near the interface determines the local liquidus temperature, which, in turn, determines whether the liquid is stable or unstable with respect to crystallization at that point. Instabilities then control the morphology of the interface between the growing crystal and the melt phase. This quantitative treatment of constitutional supercooling, which had been described qualitatively before by Rutter and Chalmers, is the treatment now found in textbooks covering solidification science. This work has played a major role in understanding the solidification of melts during crystal growth processing.

William Arthur Tiller was born in Toronto, Canada, on September 18, 1929. He grew up in Toronto, graduating from high school there in 1948. He studied engineering physics at the University of Toronto, receiving his B.S. degree (1952), M.S. degree (1953), and Ph.D. (1955). It was during his time as a graduate student that he began his work on solidification science. He did his M.S. thesis under the direction of Bruce Chalmers, a distinguished authority in materials science and his work there led to his Ph.D. thesis two years later. After receiving his Ph.D. degree, he spent nine years at the Westinghouse Research Laboratory in Pittsburgh where he built up a very active world class research group. The Westinghouse lab was one of many corporate research centers set up after WW II and based on the very successful Bell Labs model which included IBM, GE, Sperry Rand, Dupont, and Philips. In 1964, Tiller, who had established a strong reputation in solidification science, became the first to be appointed (rather than promoted) to the rank of full professor in the Materials Science and Engineering Department at Stanford University. He was able to bring with him, not only some start-up funding from AFOSR, but, also some personnel from his group: Sid O’Hara as a senior research associate and two doctoral candidates Gerald Kotler and Lemuel Tarshis who, in their doctoral thesis, continued Tiller’s earlier work on constitutional supercooling. Another very influential paper published in Metallurgical Transactions in 1972 with his Ph.D. student Robert J. Asaro, was on interface morphology development during stress corrosion cracking. However, it transcended its corrosion topic due to its inclusion, for the first time, of the concept that under strain, a flat free surface with wavy undulations will cause atoms to diffuse from the valleys to the peaks, leading to an increase in the peak heights and greater surface irregularities. This theory, decades later, became known as the Asaro-Tiller mechanism, and the foundation for a new line of theoretical work on shape evolution of strained epitaxial semiconductor films, including quantum nanostructures and quantum dots. It is very interesting to see how a theory about corrosion failure could morph into an invaluable tool for the fabrication of thin film optoelectronic devices. Three decades later A. Danescu wrote a paper entitled “The Asaro–Tiller–Grinfeld instability revisited in 2001”.

Tiller was best known for his theoretical and experimental investigations into the physics behind the freezing process for a wide range of materials, including water, metals, semiconductors, oxides and polymers. He investigated the relationships between the crystallization process and the resulting structures and properties. He exploited this knowledge of crystallization to generate new processes for ingot casting, material purification, and single crystal growth, among other technical problems.

Bill was department chairman from 1966-1971 and became a professor emeritus in 1992 at the age of 63. During his time at Stanford, he authored many frequently cited journal publications and two books, The Science of Crystallization: Macroscopic Phenomena and Defect Generation, and The Science of Crystallization: Microscopic Interfacial Phenomena, both published by Cambridge University Press in 1991. He was predeceased by his loving wife Jean in 2021 and his son in 2000.

After leaving Stanford and moving to Arizona he began to work more actively on a subject which had been of great interest to him for many years, psychoenergetics. This subject had been explored during a 1970-71 sabbatical at Oxford University on a Guggenheim Fellowship. Over the years he pursued both his conventional research on solidification topics as well as an increasing pursuit of psychoenergetic research. In Arizona he started spending most his time interacting with like-minded folks on this topic and in the ensuing decades engaged in research and writing books on pyschoenergetics. One of his books is Science and Human Transformation, a book about concepts such as subtle energies beyond the four fundamental forces, which he believed act in concert with human consciousness. Tiller appeared in the 2004 pseudo-science film What the Bleep Do We Know!? In 2015, Bill established the Tiller Foundation with its Mission to “Preserve, Advance and Promote the Psychoenergetic Science of Dr Tiller” , He summed it up in the statement below:

“With this psychoenergetic science work, a new door has been opened for deeper explorations of nature, where human consciousness, intentions, emotion, mind and spirit will play a much greater role in the great adventure of science, spirit and technology”

Finally, we can best sum up Bill Tiller’s remarkable life and contributions by this remembrance from Lem Tarshis his first doctoral student at Stanford.

"Bill Tiller was the smartest person I have ever known, and not just in the field of crystallization. He was knowledgeable about most subjects. As a teacher he was also outstanding, showing infinite patience to have students understand. I personally owe him a lot as he made me the success I became."

The Science of Crystallization: Macroscopic Phenomena and Defect Generation, Cambridge University Press, 1991, ISBN 978-0-521-38828-3
The Science of Crystallization: Microscopic Interfacial Phenomena, Cambridge University Press, 1991 (reprinted 1995), ISBN 978-0-521-38827-6
Psychoenergetic Science: A Second Copernican-Scale Revolution, Pavior Publishers, 2007, ISBN 978-1-4243-3863-4