V.E. Lashkaryov Institute of Semiconductor Physics NAS of Ukraine
National Academy of Sciences of Ukraine




Academician of Academy of Science of UkrSSR

Vadym Yevgenovych Lashkaryov

(7.10.1903 – 1.12.1974)


100th anniversarypublication

120th anniversary publication



This year it will be completed 120 years from the birthday of Academician of AS of UkrSSRVadymYevgenovychLashkaryov – theoutstanding scientist, organizer and the first director of theInstitute of Semiconductor Physics, National Academy of Sciences of Ukraine.Nowthis Institute is named by V. Lashkaryov.

V. Lashkaryov was born 07.10.1903 in Kyiv, in the family of a lawyer. His father, YevgenIvanovych, before the Revolution was a prosecutor in Kyiv Judicial Court.

Among the previous generations of the Lashkaryovsthere is a major figure of Russian diplomacy in the 18th century – Sergey LazarevichLashkaryov, whose ancestors came from an old family of Georgian nobles –Lashkarishvili. Many centuries earlier they came to Russia together with Tsar Vakhtang.

The merits of Sergei Lazarevich as a diplomat who convinced the Crimean Khan ShaginGirey to renounce the patronage of the Ottoman Empire and join Russia were highly appreciated by Catherine II. Among the descendants of Sergei LazarevichLashkaryov, there are well-known statesmen, journalists and scientists. Among the distant relatives of VadymYevgenovych on his father’s side, there is the outstanding aircraft designer Igor Ivanovych Sikorsky. After graduating from the Kiev Institute of Public Education (now Taras Shevchenko National University of Kyiv), VadymYevgenovych studied at the graduate school of the Research Department of Physics of the Kyiv Polytechnic Institute (1924–27), while working there as a teacher, and then as an assistant professor.

His researches were devoted to the physics of X-rays and the development of equipment for X-ray diffraction analysis. In particular, he developed an original method for determining the refractive index for X-rays. Abilities of V. Lashkaryov as a theoretician played a huge role in his further scientific work. They appeared already when he published his first theoretical work on the motion of matter and light in a gravitational field.The titles of works by V. Lashkaryov in the 1920s – “On the Theory of Gravitation,” “On the Theory of the Motion of Matter and Light in a Gravitational Field,” and “Derivation of the Fresnel Drag Coefficient from the Theory of Light Quanta” – illustrate a wide range of his interests related to new physics.

V. Lashkaryov took part in organization of the Institute of Physics of the Academy of Sciences of Ukraine, where he worked as the head of the department of X-ray physics in 1929–30. In accord with invitation of Academician A.F. Ioffe, in 1930 he moved to Leningrad, where for five years he first headed the department of X-rays, and then the department of electron diffraction at the Physico-Technical Institute. During this period, V. Lashkaryov carried out pioneering works on establishing the distribution of electron density and potential in a solid, and wrote the first monograph in the USSR “Electron Diffraction”. For these works, he was awarded the degree of Doctor of Physical and Mathematical Sciences without public defense of his dissertation.

At the same time, he works as an assistant professor at the Leningrad Polytechnic Institute.

From 1934 to 1939, V. Lashkaryov worked as the head of the Department of Physics at the Arkhangelsk Medical Institute, studying the biophysics of nerve fibers.In 1939,V. Lashkaryov on invitation of the Academy of Sciences of the Ukrainian SSR, returned to Kyiv, where he headed the Department of Semiconductors at the Institute of Physics of the Academy of Sciences of the Ukrainian SSR and the Department of Physics at the Kyiv University. His scientific direction was changed abruptly, and in 1941 his classic works appeared on the study of the blocking layer of copper oxide rectifiers by using a thermal probe, which led to the discovery of the p-n junction. V. Lashkaryov was the first to elucidate the role of the latter in the valve photoelectric effect. The discovery of the p-n junction, which underlies the operation of a wide class of modern semiconductor devices, at that time, outstripped the development of germanium and silicon technology, on the basis of which semiconductor diodes, triodes and integrated circuits were then created.

During the World War II, V. Lashkaryov worked in Ufa and in Moscow, where the Institute of Physics was evacuated. At the same time, he headed a laboratory at the branch research institute of the Ministry of Electronic Industry, where he worked on defense topics and created copper oxide rectifiers for field military radio-stations.

In 1944, on invitation of President of the Academy of Sciences of the Ukrainian SSR, Academician A.A. Bogomolets, V. Lashkaryov again returned to Kyiv, and in 1945 he was elected as an Academician of the Academy of Sciences of the Ukrainian SSR. From 1947 up to 1951, he worked at the Presidium of the Academy of Sciences of the Ukrainian SSR, first as Academician-Secretary of the Department of Physics, and then as a member of the Presidium.

The following years were the most fruitful period of his creative activity. A number of very important works were carried out on photoelectromotive forces in cuprous oxide. V. Lashkaryov developed their theory and showed that the non-valve electromotive force is determined by the diffusion of minority current carriers, the movement of which causes bipolar diffusion from the illuminated electrode into the depth of the sample. The role of contacts was determined, the characteristics of which determine the sign and magnitude of the photo-e.m.f. He developed the theory of capacitor e.m.f. and showed the effect of surface charges on it. The theory of nonstationary photoconductivity was developed; the possibility of controlling it by an external electric field was provided and implemented experimentally.

At the same time, the currently generally accepted concepts of the length of the diffusion displacement stretched and compressed by the field were introduced. V.Ye.Lashkayov carried out works on bipolar conductivity, theoretically considered the phenomenon of the influence of a field on the compression of current carriers to one of the contacts and their pulling deep into the sample. Thus, the mechanism of injection was revealed – the most important phenomenon on the basis of which most of semiconductor devices operates. V. Lashkaryov first discovered and investigated superlinear photoconductivity in CdS, as well as the phenomenon of photoactivation of the photocurrent output. The idea of an exciton mechanism of photoexcitation turned out to be very fruitful.

In 1948, Lashkaryov began pioneering studies of surface phenomena in semiconductors, the effect of gas adsorption on surface conductivity and contact potential difference. There obtained were a theoretical relationship relating the work function, band bending, surface charge, and changes in longitudinal conductivity. These phenomena are of great importance in the transition from discrete devices to integrated circuits and for creation of chemical sensors.

Creation of transistors based on Ge in the USA stimulated the decision-making bodies of the Soviet Union to set tasks for the development and production of domestic germanium transistors. In 1950, the Department of Semiconductor Physics of the Institute of Physics of the Academy of Sciences of the Ukrainian SSR, headed by V. Lashkaryov, was involved in solving these problems. Comprehensive scientific researches began in close collaboration both with the institutes of the USSR Academy of Sciences and with the research institutes of the ministries of electronic industry and non-ferrous metallurgy. A technology for the growth of Ge crystals and effective methods for its purification and doping were developed, the solubility and diffusion coefficients of electrically active impurities were determined, methods for studying their bulk and surface characteristics were mastered, samples of diodes and triodes were created, methods for monitoring the stability of parameters inherent to semiconductor devices under various operating conditions were developed.

V. Lashkaryov headed the Institute up to 1970. New scientists join the Institute, and its subject matter expands significantly. There is renewed interest in AIIBVI semiconductors and photoelectric phenomena in them both in theoretical and experimental research, in which V. Lashkaryov took an active part.

V. Lashkaryov paid great attention to the training of scientific personnel. Since 1944, he headed the department of physics at the Kiev State University, founded the specialization “Physics of semiconductors” there, and then the first department of semiconductors in the USSR, which he headed until 1958.

For a number of years, V. Lashkaryov was the head of the Scientific Council of the Union Academy of Sciences on the problem of “Physics of semiconductors”. While holding this position, he did a lot for the development of semiconductor science in Ukraine. At the same time, he fruitfully worked as the editor-in-chief of the Ukrainian Physical Journal.

V. Lashkaryov made an invaluable contribution to the development of semiconductor physics as an independent discipline. His name is associated with formation and development of physics and technology of semiconductors in Ukraine. Creation of V. Lashkaryov’s school was facilitated by his talent, wide erudition, deep knowledge in physics, quick orientation in its new directions, and great personal attractiveness.

On everyone who was lucky enough to know this man closely, he had a strong influence by his personality, subtle understanding of physics, perhaps to a greater extent than direct scientific recommendations and direct assistance in the work.