The intensive searching for a reliable semiconductor device to amplify feeble electric signals, which gave bith to the modern solid-state components, was the saga of many scientists, engineers and inventors. Due to the importance of their pioneering work among them are:

Edouard Branly working at his laboratory circa end of XIX century.
Edouard Branly
Was born in Amiens, France in October 23rd 1884. He completed his studies at the Ecole Normal Supéreure, in Paris. At Sorbonne he worked in the physics laboratory and won his Doctor in Physics degree. In his studies of electrical conductivity, he observed that some materials, in powder form, were affected in their electrical conductivity by electromagnetic waves.
In 1885, he invented the coherer, the first Hertzian wave detector. Edouard Branly passed way in March 24th 1940 in Paris.

Erwin Schrodinger
Viennese physicist. In 1933 won the Nobel Prize together with P.A. Dirac for his contribution in the new theory of undulatory mechanics applied on the atom structure.

Greenleaf Whittier Pickard
Electrical engineer educated at Harvard University and Massachusetts Institute of Technology. In 1903 he started his researches about the application of minerals as Hertzian waves detectors. During his studies he evaluated many types of natural materials concluding that Galena proved to be the best type of detector although it lacked ruggedness and stability. Besides his discovery of the principle of Hertzian waves detection using crystals he invented also the "Perikon" detector, made by pressing Zinc Oxide and Chalcopyrite. Pickard worked as a consulting engineer and had more than 100 patents to his credit.

Jack St. Clair Kilby
Was born in Jefferson City, Missouri, USA. He started his carrer in Electronics working as engineers in the Gobe-Union company manufacturer of radio receivers. In 1958 working in the micro miniaturization department of Texas Instruments he invented the integrated circuit.

John Bardeen
American physicist from Maison, Wisconsin. In 1908 he achieved his Ph.D. in Solid-State Physics from Princenton University. He was the author of the superconductivity theory as well as one of the co-inventors of transistor. In 1956 he shared the Nobel Price with William Shcockley and Walter House Brattain.

Walter House Brattain
One of the co-inventors of transistor. He achieved his Ph.D in Physics from Minnesota University when he had the opportunity to attend to several lectures about the new field of Quantum Mechanics presented by several-respected scientists such as Edwin Schrodinger, James Franck. In 1929 he started his work at Bell Telephone laboratories in the field of thermionic emission as well as other material surface properties. Considering his expertise in Solid-State Physics in 1931 he was appointed to work with J.A.Backer for the development of a Copper Oxide rectifier.

Walter Schottky
Was born in July 23, 1886, in Zurich Switzerland. He studied Physics at Humboltt University in Berlin. In 1912 after receiving his Ph.D., Schottky moved to Jena, Germany, where he worked with Max Wien and soon he started his studies about the interaction of electrons and ions in vacuum and solid bodies.
In 1919 working at Simens Company he invented the tetrode valve. After several years of researches and studies in 1929 he published the book: "Thermodynamik".
Through his enormous research work about smiconductor materials, in 1938 he created a theory that explained the rectifying behaviour of a metal-semiconductor contact as dependent on a barrier layer at the surface of contact between the two materials. The metal semiconductor diodes later built on the basis of this theory are known as barrier diodes. Walter Schottky passed way in Pretzfeld, Germany in March 4th 1976.

William Bradford Schockley
American physicist was born in London, England in 1910. He studied with John Slater a pioneer of Quantum Mechanics. Just after starting his researches on the Solid-State Physics at Bell Laboratories, in 1936 he was awarded a doctorate in Physics from Massachussets Institute of Technology. Schockley was one of the co-inventors of transistor.