Abstract: A method of obtaining a crystal by crystal growth in the liquid phase from a seed in the form of a plate taken from a primary crystal, which method comprises at least two steps constituted firstly by forming first crystal growth to obtain a secondary crystal from a first seed taken from said primary crystal in a first growth zone, and secondly in performing second crystal growth from a second seed taken from said secondary crystal in a second growth zone, said first and second seeds being selected so that few of the dislocations that they contain propagate respectively into the second zone of the secondary crystal or into the first growth zone of the resulting crystal. According to the invention said first and second crystal growth steps are performed in different growth directions. Application to monocrystals of quartz, or of materials that are isomorphs of quartz, such as berlinite, and that are intended for use in making electronic components, in particular oscillators and filters.

Abstract: A method for producing a crystal film of an organic compound from a molten liquid or solution of the organic compound on a substrate or between a pair of substrates, the substrate or at least one of the pair of substrates having on a part of the surface thereof a three-dimensional geometrical structure capable of controlling the direction of the crystal growth of the organic compound, and the other part of the surface thereof than the part having a three-dimensional geometrical structure being smooth. The resulting crystal film comprises a sufficiently large single crystal for application to a practical element with its orientation controlled in an arbitrarily selected direction.