Kurt Lehovec

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Kurt Lehovec
Kurt Lehovec.jpg
Born 12 June 1918
Ledvice, Bohemia
Died17 February 2012 (2012-02-18) (aged 93)
California, USA

Kurt Lehovec (June 12, 1918 February 17, 2012) was one of the pioneers of the integrated circuit. He innovated the concept of p-n junction isolation used in every circuit element with a guard ring: a reverse-biased p-n junction surrounding the planar periphery of that element. This patent was assigned to Sprague Electric. [1] [2]

Integrated circuit electronic circuit manufactured by lithography; set of electronic circuits on one small flat piece (or "chip") of semiconductor material, normally silicon

An integrated circuit or monolithic integrated circuit is a set of electronic circuits on one small flat piece of semiconductor material that is normally silicon. The integration of large numbers of tiny transistors into a small chip results in circuits that are orders of magnitude smaller, cheaper, and faster than those constructed of discrete electronic components. The IC's mass production capability, reliability and building-block approach to circuit design has ensured the rapid adoption of standardized ICs in place of designs using discrete transistors. ICs are now used in virtually all electronic equipment and have revolutionized the world of electronics. Computers, mobile phones, and other digital home appliances are now inextricable parts of the structure of modern societies, made possible by the small size and low cost of ICs.


Because Lehovec was under salary with Sprague, he was paid only one dollar for this invention.

Lehovec was born June 12, 1918 in Ledvice, in northern Bohemia, of the Czech Republic. He was educated there and went to the US in 1947 under the auspices of Operation Paperclip [3] which allowed scientists and engineers to emigrate. With Carl Accardo and Edward Jamgochian, he explained the first light-emitting diodes [4] citing previous work by Oleg Losev.

Ledvice Town in Czech Republic

Ledvice is a town in the Czech Republic located in the Teplice District in the Ústí nad Labem Region, about 7 km southwest of Teplice.

Kingdom of Bohemia Monarchy in Central Europe, predecessor of modern Czech Republic

The Kingdom of Bohemia, sometimes in English literature referred to as the Czech Kingdom, was a medieval and early modern monarchy in Central Europe, the predecessor of the modern Czech Republic. It was an Imperial State in the Holy Roman Empire, and the Bohemian king was a prince-elector of the empire. The kings of Bohemia, besides Bohemia, also ruled the Lands of the Bohemian Crown, which at various times included Moravia, Silesia, Lusatia, and parts of Saxony, Brandenburg, and Bavaria.

Czech Republic Republic in Central Europe

The Czech Republic, also known by its short-form name, Czechia, is a landlocked country in Central Europe bordered by Germany to the west, Austria to the south, Slovakia to the east and Poland to the northeast. The Czech Republic covers an area of 78,866 square kilometres (30,450 sq mi) with a mostly temperate continental climate and oceanic climate. It is a unitary parliamentary republic, with 10.6 million inhabitants; its capital and largest city is Prague, with 1.3 million residents. Other major cities are Brno, Ostrava, Olomouc and Pilsen. The Czech Republic is a member of the European Union (EU), NATO, the OECD, the United Nations, the OSCE, and the Council of Europe.

The important case of fast ionic conduction in solid states is one in a surface space-charge layer of ionic crystals. Such conduction was first predicted by K. Lehovec in the paper “Space-charge layer and distribution of lattice defects at the surface of ionic crystals” ( J. Chem. Phys. 1953. V.21. P.1123 -1128). As a space-charge layer has nanometer thickness, the effect is directly related to nanoionics (nanoionics-I). The Lehovec effect forms a basis for a creation of multitude nanostructured fast ion conductors as used in modern portable lithium batteries and fuel cells.

Nanoionics is the study and application of phenomena, properties, effects and mechanisms of processes connected with fast ion transport (FIT) in all-solid-state nanoscale systems. The topics of interest include fundamental properties of oxide ceramics at nanometer length scales, and fast ion conductor /electronic conductor heterostructures. Potential applications are in electrochemical devices for conversion and storage of energy, charge and information. The term and conception of nanoionics were first introduced by A.L. Despotuli and V.I. Nikolaichik in January 1992.

In materials science, fast ion conductors are solids with highly mobile ions. These materials are important in the area of solid-state ionics, and are also known as solid electrolytes and superionic conductors. These materials are useful in batteries and various sensors. Fast ion conductors are used primarily in solid oxide fuel cells. As solid electrolytes they allow the movement of ions without the need for a liquid or soft membrane separating the electrodes. The phenomenon relies on the hopping of ions through an otherwise rigid crystal structure.

Lehovec was a Professor Emeritus at the University of Southern California in Los Angeles, California, and after retirement from USC Lehovec took to writing poetry. [5] He lived in Southern California until his death in 2012 at the age of 93. [6]

University of Southern California Private research university in Los Angeles, California, United States

The University of Southern California is a private research university in Los Angeles, California. Founded in 1880, it is the oldest private research university in California. For the 2018–19 academic year, there were 20,000 students enrolled in four-year undergraduate programs. USC also has 27,500 graduate and professional students in a number of different programs, including business, law, engineering, social work, occupational therapy, pharmacy, and medicine. It is the largest private employer in the city of Los Angeles, and generates $8 billion in economic impact on Los Angeles and California.

Southern California Place in California, United States

Southern California is a geographic and cultural region that generally comprises California's southernmost counties, and is the second most populous urban agglomeration in the United States. The region is traditionally described as eight counties, based on demographics and economic ties: Imperial, Los Angeles, Orange, Riverside, San Bernardino, San Diego, Santa Barbara, and Ventura. The more extensive 10-county definition, which includes Kern and San Luis Obispo counties, is also used and is based on historical political divisions.


See also


  1. Kurt Lehovec, U.S. Patent 3,029,366 awarded on April 10, 1962, filed April 22, 1959.
  2. Robert Noyce credits Lehovec in his article – "Microelectronics", Scientific American , September 1977, Volume 23, Number 3, pp. 63–9.
  3. Kurt Lehovec's Professional Career [ permanent dead link ]
  4. K. Lehovec, C. A. Accardo, AND E. Jamgochian, "Injected Light Emission of Silicon Carbide Crystals". Archived 2013-10-06 at the Wayback Machine ., The Physical Review83, #3, 603-607 August 1, 1951
  5. Some of Lehovec's poetry publications
  6. Obituaries: Donald Payne, Kurt Lehovec, Los Angeles Times , retrieved 18 July 2014

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