A dielectric study of triglycine sulfate crystals was carried out and the phase transition temperatures were determined for samples grown at temperatures below 0oC. The influence exerted by a single-crystal silicon substrate treated by various methods on the shape of triglycine sulfate crystals was examined. Crystals of triglycine sulfate, (NH 2 CH 2 COOH) 3 . H 2 SO 4 (TGS), are primarily known as classical ferroelectrics [1,2]. Their ferroelectric properties are mainly determined by hydrogen bonds between atoms of nitrogen, hydrogen, and oxygen [1,3].Commonly these crystals are grown from aqueous solutions at temperatures of 20 3 60oC. The Curie point (T c ) of crystals of this kind (49oC) in a certain way characterizes the strength and rigidity of those bonds, which, undergoing transformations under the action of external factors (electric field, temperature), lead to formation and transformations of the domain structure of the crystals. Pyro-, piezoelectric, and other electrical properties of TGS crystals, which determine their practical importance and possible applications, depend on hydrogen bonds. Studies of the composition, structure, and properties of TGS crystals, which contain an amino acid (glycine), in relation to methods and conditions of their synthesis, with TGS used as a model material, yield valuable information about properties of various amino acids and their compounds. At the same time, it is of interest to study the possibility of directed modification of the properties of these TGS crystals in order to expand the area of their practical application. As an example, mention can be made of investigations devoted to doping of these crystals with various organic and inorganic components [1] and to their radiation treatment.The properties of TGS crystals largely depend on the state of water both in their synthesis and growth and under the action of various external factors. With account of this fact, the range of variation of these factors was significantly expanded, primarily via a shift of the temperature range of crystal growth to below 0oC, where water can undergo phase transformations together with TGS. Simultaneously, it was decided to examine the effect of water vapor on the properties of the crystals. Finally, a study of TGS crystals grown on the surface of silicon single crystals pretreated by various methods was commenced with account of the fact that silicon is the basic material of solid-state electronics.To find the conditions for growth of TGS crystals from aqueous solutions below 0oC, the eutectic point was determined in the phase diagrams of the systems water3glycine and water3TGS [4]. For this purpose, a method based on analysis of the kinetics of fractional melting of ice ingots crystallized from aqueous solutions with different initial concentrations has been developed [5] in view of the fact that attainment of a thermodynamic equilibrium in aqueous solutions at T < 0oC is hindered and requires a long time. The temperature and concentration of components at the eutectic point o...
