It is the goal of the author to make interesting and useful for professors teaching specific courses in solid state physics, optics and materials science, as well as for researchers, managers of electronic industry, students and university libraries the major contents of this talk, already published and widely presented materials as well as the book planned for 2015 edition in Apple Academic Press. The talk focuses on opportunities to change within broad limits properties of semiconductors and using only one of them to overlap necessary set of the device parameters, which earlier could be achieved with a number of diverse materials. All the author’s efforts are devoted to the achievement of this goal since his education and growth of the collection of semiconductor crystals at the St. Petersburg State Polytechnic University (1958-1964) and up to now at scientific and industrial institutions of Russia, Moldova, Germany, Italy and the United States. This 50 years period of collaboration with the world-known, highly qualified specialists gives a unique opportunity to observe, investigate and collect interesting results on the long-term evolution of properties of the grown in 1960th crystals. The talk demonstrates the results of development of growth technology for perfect and free of contamination gallium phosphide (GaP) crystals and investigation of influence of crystallization conditions on quality and properties of the crystals. The long-term ordered and therefore close to ideal crystals repeat behavior of the best nanoparticles with pronounced quantum confinement effect. These perfect crystals are useful for application in top-quality optoelectronic devices as well as they are a new object for development of fundamentals of solid state physics. Since the time of original preparation by the author in the 1960s of gallium phosphide crystals doped by nitrogen (GaP:N), followed by the introduction of the excitonic crystal concept in the 1970s, the best methods of bulk, film and nanoparticle crystal growth were elaborated. The results of semi centennial evolution of GaP:N properties are compiled in the talk. Novel and useful properties of perfect GaP including an expected similarity in behavior between nanoparticles and perfect bulk crystals as well as its stimulated emission, very bright and broadband luminescence at room temperature were observed. These results provide a new approach to selection and preparation of perfect materials for optoelectronics and a unique opportunity to realize a new form of solid-state host - the excitonic crystal as high intensity light source with expected low threshold for generation of non-linear optical effects. Using the example of GaP, here is proposed the cheap, resource-saving and impactful way for development of optoelectronics with the help of a special transformation of an ordinary semiconductor into the base material for various device structures. Elaborating growth and crystal storage technologies, methods of nanocrystal and nanocomposite preparation and investigating luminescence, photoconductivity, Raman light scattering and other phenomena, it is shown that compared with the freshly grown crystals, the long-term, tens of years, ordered GaP, its artificial analogues and nanoparticles have very interesting for different application properties, which give an opportunity to apply in optoelectronic device structures with various spectral regions and bandwidth, light emissive maximum position and its intensity only this material instead of a lot of currently used compounds.