Prytchyn S. Development of technology for production of gallium arsenide substrates for microelectronic products

The dissertation is devoted to solving actual scientific-practical problem - improving the quality GaAs substrates by developing new manufacturing technology substrates, improvement of mathematical models, improvement of techniques, methods and devices of nondestructive control of substrates quality in industrial environments. Due to results of mathematical modeling data on values of mechanical properties of GaAs substrates at random crystallographic directions are specified. The influence of the magnitude of residual stresses in the elastic constants с11, с12, с44 is defined. The conditions which provide mechanical stability of GaAs substrate under the influence of residual stresses on it are determined. A number of methods and devices are developed in the paper. Also methods in terms of mass production are improved, including: - method, device "Polaron - 4"; method of nondestructive testing of residual stresses in GaAs substrates is improved; - method, device "TV-Dislok 1"; method of nondestructive testing dislocation density in GaAs substrates is improved; - method, device "AKIDP - 1"; method of nondestructive testing of flatness deviation of GaAs substrates is improved. The control device of bar diameter in the process of growth is developed. This device provides precision of control at least ± 1.5 mm. It allowed through better work of system of management of growth to reduce the level of residual stresses to a value less than 40 MPa and dislocation density less than 1.3 x 105 cm-2. The proposed technology of substrates GaAs producing ensured improving the quality substrates GaAs, in particular, reducing residual stresses level by 10 %, reducing the dislocation density by 12 %, reducing the deviations from the flatness of substrates by at least 20 % compared with the existing technology that can increase the output of suitable devices for 5-7 %.