Trubitsyn Yu.V. Ultra-pure and structurally perfect silicon monocrystals for detectors and receivers of radiation. - Manuscript. Thesis for competition on engineering science Doctor's degree by specialty 05.27.06 - technology, equipment and manufacture of an electronics. - Kherson state technical university, Kherson, 2001. The thesis is dedicated to issues of manufacturing method design and research of electrophysical parameters of highpure and structurally perfect Si monocrystals for detectors and receivers of radiations. 46 proceedings (26 papers, 20 inventions) are defended, in which set of physical and mathematical models of processes for account of technological conditions of float zone purification and growing of superpure Si monocrystals with the prescribed electrophysical and structural parameters and for definition of fitness of a polycrystalline Si for obtaining superpure Si monocrystals is constructed and experimentally grounded. The results of a research of variuos sources of technologi cal contaminatings are stated, the mechanisms of complexing and chemico-physical transformations of components, which render influence to reproducibility, exactitude, and homogeneity of a doping of Si from a gas phase are ascertained. It is established that apparatus background and residual atmosphere are the basic carbon and oxygen contamination sources of a traditional level (і5.1016 cm-3) into grown Si monocrystals. For the first time are offered, scientifically grounded and realized in industrial manufacture the fundamentally new technological processes: method for coaxial non reloading vertical float zone purification of polycrystalline Si rods with diameter up to 105 mm; method for pulsating float zone purification and Si monocrystals growing; method for low-temperature and radiation-thermal rehabilitation of electrophysical parameters of superpure dislocation-free Si monocrystals and for increasing of their plasticity at mechanical effects; method for obtaining of exactly compensated high-ohmic Si monocrystals with n and p-types of conductivity for it using in photodetectors and detectors of nuclear radiations on the basis of neutron and gamma-transmutation doping. An industrial series of inductive thermal systems for group, individual, non reloading float zone purification of silicon rods for various purposes and for growing of dislocation-free Si monocrystals with diameter of 25-105 mm is developed. The techniques for researching of distribution pattern and behavior of C, Fe, P, In, Ga, Na, H and Ar impurities during growing and aftertreatment of superpure silicon monocrystals with applying of radioactive indicators 14C, 55Fe, 59Fe, 32P, 33P, 114In, 72Ga, 22Na, 3H and Кr are developed. The influence of various technological factors to character of distribution and types of microdefects of crystalline structure in dislocation-free Si monocrystals is investigated. On the basis of the analysis of criteria of heat exchanging processes the growing conditions of dislocation-free Si monocrystals with th e given type of microdefects are defined. The technological conditions, at which the growing of monocrystals with only D - type microdefects ensuring preferential parameters of devices structures are developed. It is shown, that introduction into volume of superpure Si monocrystals (where density levels of a basic impurity and densities of electrical active defect-impurity centres are commensurable) of special doping components: isovalent impurities (IVI) - Ge, Sn, Hf with concentration more than 5.1018 сm-3 and of rare-earth elements (REE) - Er, Ho, Dy, Gd, Yb, Lu with concentration more than 1.1015 сm-3 renders strong influence to a condition of pint defect complexes and processes of defect-impurity interaction; reduces the contents of background impurities Au, Cu, Na, Fe, Ti, W and C in Si at the expense of increase of segregation efficiency; reduces the contents of optically active O up to concentration less than 2.1015 cm-3 in Si; reduces the contents of an admixture Р in Si, that promotes reduction of a compensation degree and, hence, results to increasing of an axial and radial homogeneity of specific resistance distribution; suppresses creation of growth nonlinear defects and augments ?. Besides the suppression of optically active center generation is occurred during thermal and nuclear influence on monocrystalline Si, and the maximum effect is appeared in oxygen containing material. Si, which are grown in conditions of an additional doping by IVI and REE, is a perspective material for manufacture of devices, for which the minimum contents of background technological admixtures is the determining factor, in particular, for example, for detectors of ionizing radiations. Key words: polycrystalline and monocrystalline silicon, float zone melting, segregation, impurities, conductivity type, specific electrical resistance, minority carrier life-time, doping.
