Our Patron

Professor Jan Czochralski (1885-1953)

The following article was published in the newsletter American Crystallographic Association - volume 27, issue 2 - autumn 1998. The article is presented in our WWW pages with the kind permission of the AACG Editor. The source code of the article was kindely delivered by the author, Dr Pawel Tomaszewski.

Professor Jan Czochralski (1885-1953)
AND HIS CONTRIBUTION TO THE ART AND SCIENCE OF CRYSTAL GROWTH

Pawel E. Tomaszewski
Institute of Low Temperature and Structure Research, Polish Academy of Science
ul. Okolna 2, P.O. BOX 1410, 50-950 Wroclaw 2, POLAND

There are not many Polish scientists in the fields of physics and chemistry whose names are well known all over the world as Jan Czochralski. Apart from Mikolaj Kopernik, Maria Sklodowska-Curie, Marian Smoluchowski and Kazimierz Fajans, probably only Jan Czochralski has found a permanent place not only in the history of these sciences but also in the modern scientific terminology. Scientific aerias, such as solid state physics, electronics and materials science, which created the foundation of modern technology, owe, at least in part, their progress and present position to him. His first discovery in the beginning of the 20th century was rediscovered later in the middle of the century by American semiconductor technology specialists, who his crystal pulling technique the Czochralski method. This secured for Jan Czochralski a remarkable position in the modern science. It is important, therefore, to know who Czochralski was and his scientific achievements.

Jan Czochralski belonged to a generation actively participating in the exciting progress of science and technology at the beginning of the 20th century. For example, the first flight of an airplane by the Wright brothers (1903), condensation of helium (H. Kamerlingh-Onnes, 1908), the discovery of the atom nucleus (E. Rutherford, 1911), the discovery of superconductivity (H. Kamerlingh-Onnes, 1911), the diffraction of X-rays by crystals (M. von Laue, 1912), the model of the atom (N. Bohr, 1914), the theory of relativity (A. Einstein, 1916), the first flight over the Atlantic (J. Alcock and A.W. Brown, 1919) and the formulation of quantum mechanics (W. Heisenberg, 1925).

Jan Czochralski was born on 23 October 1885 in Kcynia in the Paluki region which was then under the Prussian domination. He was the eighth child of the Polish craftsmen Franciszek Czochralski and his wife Marta from the Suchomski family. The Czochralskis have been carpenters for many generations. Franciszek Czochralski, grandfather of Jan, and his coworkers are shown in Fig. 1 in front of the family house in about 1904. Thus it is not surprising that Jan loved both hard work and the native land.

In accordance with the wish of his father, Jan completed teachers' seminar in Kcynia. He was already interested in chemistry during his school days. However, even though he had passed his matriculation, he did not accept his matriculation certificate because he had gotten poor grades. Lack of this document closed the road to teaching, higher education and a scientific career. Thus, he left for Krotoszyn [2] to work in a drugstore and to study chemistry on his own. He promised his parents that he would return to Kcynia when he became famous.

During this period, Berlin was the nearest academic city and the place where many Poles studied. Jan Czochralski went there at the end of 1904 and began to work in the pharmacy and drugstore of Dr. A. Herbrand in Altglienicke (today one of the districts of Berlin). He carried out analyses of ores, oils, greases and metalsm and acquired knowledge and independence in formulating research topics. Later he worked for a short period in the laboratory of Kunheim and Co. in Niederschoenweide near Berlin and then in Allgemeine Elektrizitaets-Gesellschaft (AEG). The job in Kabelwerk Oberspree and the two years spent in their research laboratories prepared him to become head of the laboratory of steel and iron research. This laboratory dealt with the checking the quality and purity of metals and alloys and was engaged in the refinement of copper. Figure 2 shows Jan Czochralski in his Berlin laboratory, circa 1907. Simultaneously he attended lectures on chemistry at the Charlottenburg Polytechnic near Berlin. Fig. 3 is a portret of Jan Czochralski in 1907. In about 1910 he obtained the title of chemist-engineer. From 1911 to 1914 he was an assistant of Wichard von Moellendorff with whom he published his first paper devoted to the crystallography of metalls, or more precisely to dislocation theory (Technologische Schluesse aus Kristallographie der Metalle [Technological conclusions from metal crystallography], Zeitschrift des Vereines Deutscher Ingenieure 57, 931-935, 1014-1020 (1913)).

The main task of Czochralski was the introduction of aluminum to electrical engineering i.e. pioneering works on the technology of the production of sheets, wires and pressings of aluminum, the study of aluminum alloys, and standardization of metallographic studies. Metals and metallography became Czochralski's passion. His achievements were outstanding and maded new roads in metallurgical science and technology. Czochralski's fame grew slowly and steadily.

The Czochralski method of growing single crystals brought Jan Czochralski his greatest publicity. The method was developed in 1916 and was initially used to measure of crystallization rate of metals. The method was developed as a result of an accident and through Czochralski's careful observation. One evening he left aside a crucible with molten tin and returned to writing notes on the study carried out on a crystallization study. At some moment, lost in thoughts, instead of dipping his pen in the inkpot, he dipped it in the crucible and withdrew it quickly. He observed then a thin thread of solidified metal hanging at the tip of the nib. The discovery was made! The nib slot, in which crystallization was initiated, was replaced by a special narrow capillary and in some cases by a seed of the growing crystal. Czochralski checked later that the crystallized wire was a single crystal. The crystals obtained in that way had diameters of about a millimeter and lengths up to 150 cm. Czochralski published a paper on the study of the rate of crystallization of tin, zinc and lead, and the maximum rate of pulling of a crystal was recognized as the characteristics of the crystallizing material (Ein neues Verfahren zur Messung des Kristallisationsgeschwindigkeit der Metalle [A new method for the measurement of crystallization rate of metals], Z. phys. Chem. 92, 219-221 (1918); the paper was received in the editorial office on 19 August 1916). Figure 4 is a diagram of the technique from the manuscript. Details of the new method, but without any figure, appeared earlier in another paper published by Czochralski: Zeitschrift des Vereines Deutscher Ingenieure 61, 345-351 (1917)). He is also the author of the first attempt at creating a microscopic theory of recrystallization (Int. Zeitschrift fuer Metallographie 8, 1-43 (116)).

The application of the Czochralski method exclusively as a technique for obtaining single crystals is due to W. von Wartenberg (Verhandlungen der Deutsche Phys. Gesellschaft 20, 113 (1918)). Thus, the Czochralski method was a method of producing large single crystals by inserting a small seed crystal into a crucible filled with molten material, then slowly pulling the seed up from the melt with its simultaneous rotation. Later modifications of this method have also been reported. It is interesting to note that in his own investigations Czochralski obtained single crystals by the Bridgman method. The Czochralski method was completely forgotten after the II World War. However, increasing demand for semiconductor electronic materials in 1950 led the Americans G.K. Teal and J.B. Little from Bell Telephone Laboratories rediscovered and widely apply this growth method, giving it a world-wide fame as the Czochralski method for growing large single crystals on an industrial scale (Growth of germanium single crystals, Phys. Rev. 78, 647 (1950) and Bull. Amer. Phys. Soc. 25, 16 (1950)). At the present time no other crystal growth method can compete with the Czochralski method.

In 1917 Jan Czochralski moved to Frankfurt on Mein and, combining scientific research with workshop efforts, organized the Laboratory of Metal Science of the Metall Gesellschaft A.G.. Several valuable scientific papers and patents were developed there. Among the patents was the highly famous patent on a tin-free bearing alloy for railways, called metal B, patented in 1924 and bought by many countries all over the world, including USA, France and England. He also pioneered investigations of the anisotropy of the hardness of single crystals (works between 1913 and 1923), which are of great importance for the plastic treatment of materials.

Czochralski wrote two handbooks: Lagermetale und ihre technologische Bewertung [Bearing metal and its technological evaluation] (coauthored with G. Welter, 1920, 1924) and Moderne Metallkunde in Theorie and Praxis [Modern metal science in theory and practice] (1924), which were later translated into several languages.

Many of Czochralski's works were military secrets (later even in Poland) and have never been published. It is known, however, that during this Frankfurt period he authored reports containig more than two thousand pages.

In 1919 Jan Czochralski with a few friends founded German Society for Metals Science (Deutsche Gesellschaft fuer Metallkunde), and in 1925 became its president. He was also a honorary member of the Institute of Metals in London.

Poland revived after the I World War and required knowledge and capabilities of its sons and daughters scattered all over the world. Jan Czochralski did not forget about his native land despite his high position in the German industry. He returned to Poland at the invitation of the President of Poland, Ignacy Moscicki, an eminent professor of chemistry, and in 1929 he took the position of a professor in the Faculty of Chemistry at the Warsaw University of Technology, where he also obtained his first honorary doctorates. Figure 5 shows Prof. Jan Czochralski in 1929. He invested the fortune he brought from Germany in Polish industry and arts. (i.e. founded artistic scholarships). The drawing rooms of his home became popular in Warsaw. Once again he organized his scientific workshop: Department of Metallurgy and Metals Science in the Warsaw University of Technology and Institute of Metallurgy and Metal Science. The latter mainly working for the Ministry of Defence. Both of these scientific institutions were equipped with the latest apparatus. Prof. Czochralski also organized Metallurgical Section in the Chemical Research Institute, one of the leading independent research institutions in the country. Figure 6 shows the Polish Prezydent visiting the Czochralski's laboratory.

In the institutions mentioned above, Prof. Czochralski continued the studies which he undertook earlier in Germany. He was still engaged in measurements of the rate of crystallization of metals. Figure 7 shows the apparatus used for sodium studies in 1936. He also studied the elastic properties of metals and alloys and their corrosion in different gas atmospheres. In addition, Czochralski investigated the influence of experimental conditions on the shape of crystals obtained by his growth method (Wiadomosci Instytutu Metalurgii i Metaloznawstwa 3, 69-74 (136); 85-88 (1937)) and studied another method of obtaining single crystals, by recrystallization of initial material.

He had fulfilled his pronnouncement of youth. He was famous and prosperous, but he also remembered his origin. Jan Czochralski did not forget his native Kcynia where his mother lived. In Kcynia he had his second home (figure 8).

Figure 9 shows Jan Czochralski with his wife and daughter. He was very interested in everything that concerned his native surroundings. He supported both archeological studies as well as the geological search for petroleum beds. He was also interested in the progress of Polish economy and there are even some papers retained from that period. There is also the term Czochralski process, mentioned in the McGraw-Hill Dictionary of Scientific and Technical Terms (3rd edition, p. 408), in the field of ecology.

In the winter of 1939 at the beginning of the II World War, at the request of his coworkers at his institute Jan Czochralski organized the Department of Materials Research as a service institution. Figure 10 shows Prof. Jan Czochralski in his office in Warsaw University of Technology. [3] At the price of producing spare parts for the Germans and the city self-government administration, the service institution provided jobs and security (giving appropriate documents) to dozen of persons in occupied Warsaw. It also supplied the National Army [4] fighting for the freedom of the country.

Cooperation with the National Army (for example, extracting persons imprisoned by the Germans, helping the Jewish ghetto in Warsaw, saving collections from destroyed museums, and rendering help to Polish men of letters and artists) was the natural feature of the activities of Czochralski. He considered it his moral duty to use his German connections and a good knowledge of the German language for the Polish cause, risking both being imprisoned by the Germans and/or being suspected of collaboration. And indeed after the war, the senate of Warsaw University of Technology accused him of collaboration with the Germans and turned down his offer to continue his research, excluding him from the scientific life of the country. This was the price paid by Czochralski for his wish to serve his Motherland.

Professor Czochralski was deeply embittered and decided to return to native Kcynia. With his family he founded there a drug company, BION, producing different types of cosmetics and household chemicals. In this way the circle closed. Jan Czochralski returned to Kcynia and to the chemistry of drugs and pharmacy. On 22 April, 1953 he died of heart disease and was buried in Kcynia.

Professor Jan Czochralski's life was colorful and tragic. He was an eminent scientist, both as an observer and a practitioner in the area of pure and technical sciences, and a humanist with diverse interests. He wrote scientific papers as well as poetry and helped the industry as well as young artists. He was widely known before the World War II, but was then forgotten. However, he knew his own value, which he achieved through hard work, and did not let others laugh or disdain him. Some people considered him dry, selfish and uncaring (because he was demanding and secretive) while others were fascinated by his charming smile and faith in mankind.

Thus, from different sources emerges a picture of complete contradiction. However, there is no doubt that he remains in the history as a great Polish whose name is well known in present day crystallography, materials science and electronics. For this reason the Tenth European Crystallographic Meeting, organized in Wroclaw in 1986, was dedicated to Professor Jan Czochralski to commemorate the seventieth anniversary of the discovery of the Czochralski method. Since its foundation in 1991, the Polish Society for Crystal Growth commemorates him in the form of Czochralski Lecture, which is delivered as the opening lecture of every Polish Crystal Growth Conference by a distinguished scientist with recognized contribution in crystal growth related fields. Recently, this Society changed its name to Czochralski Polish Society for Crystal Growth.

The list of publications by Jan Czochralski numbers about one hundred positions. A complete list of these papers may be found in his biography (Wiadomosci Chemiczne 41, 597-634 (1987)).

A specific feature of his work and his achievements was the enrichment of the means and methods of research. His solutions of successive scientific problems required construction of suitable apparatus, special methods of measurements, and adaptation of methods known in other fields of science. This led to the following:

• Studies of the rate of crystallization of metals resulted in the Czochralski method of growing single crystals which has become very popular and widely applied till today,
• Studies on the recrystallization of metals resulted in recrystallization diagrams, which are used commonly for describing the properties of materials,
• The method of analysis of heating curves was developed, which is used for the measurements of self-improvement of materials,
• Metallographic investigations required the development of new methods of etching, which inter alia resulted in Czochralski reagents for the etching of gold,
• The method of quantitative determination of nonmetallic precipitates in iron and steel (microscopic observations and analysis of electrical resistivity of precipitates and the matrix) was born out of studies of the quality of materials,
• An attempt to detect and identify nonmetallic precipitates using a specially constructed "radiomicroscope",
• Studies of corrosion of different materials stimulated the development consistent and controlled conditions of measurements,
• Lack of X-ray equipment in Warsaw University of Technology led to the development of non-X-ray techniques (etch figures, distorted reflections and traces of mechanical deformation; methods taken from mineralogy) for determining the orientation of metal single crystals
• Introduction of new X-ray methods to metals science and their wide application (among others, for studies of the influence of deformation on diffraction patterns).
  ACKNOWLEDGEMENTS

  The present article on the life of Prof. Jan Czochralski took about ten years of research of source materials and numerous interviews and would not have been completed without the enormous assistance of many persons, offices, archives and museums in Poland and abroad. The author is grateful to the members of the family of Professor Czochralski in Poland and abroad, who searched and placed at the author's disposal several valuable materials and documents. He also thanks Professor Kazimierz Lukaszewicz for his encouragement in these fascinating searches and analyses, and to Professor Keshra Sangwal for translating the article into English.

  FOOTNOTES

  [1] In 1795 Poland was eliminated from the map of Europe and divided between Prussia, Austria and Russia. The region of Wielkopolska, including Paluki, became a part of Prussia (since 1871, the German Empire). Poland regained independence in 1918.
  [2] The surname of the Nobel prize winner for the discovery of fullerenes, Sir H.W. Kroto, is associated with this town, where his ancestors lived.
  [3] After the occupation of Poland, all Polish institutions of higher education were closed.
  [4] Armia Krajowa (AK) was an underground army of the Polish State, with headquarters of in London, conducting training and guerrilla struggle in the territories occupied by Nazi Germany and the USSR.

  The article was prepared for WWW PTWK by W. Polak