Producing volume single crystal, comprises disposing seed crystal in crystal growth region of growth crucible with initial growth surface and center central longitudinal axis, and growing the single crystal by deposition onto seed crystal

摘要

The process comprises disposing a seed crystal (7) in a crystal growth region (5) of a growth crucible (3) with initial growth surface and a center central longitudinal axis, where the seed diameter is 10% less than a crystal diameter of a volume single crystal to be produced, growing the single crystal by deposition onto the seed crystal in a growth direction oriented parallel to the central longitudinal axis, and adapting the initial growth surface of the seed crystal to driving force for the growth of the single crystal at surface distribution adjusting itself to begin the crystal growth. The process comprises disposing a seed crystal (7) in a crystal growth region (5) of a growth crucible (3) with initial growth surface and a center central longitudinal axis, where the seed diameter is 10% less than a crystal diameter of a volume single crystal to be produced, growing the volume single crystal by deposition onto the seed crystal in a growth direction oriented parallel to the central longitudinal axis, and adapting the initial growth surface of the seed crystal to a driving force for the growth of the volume single crystal at a surface distribution adjusting itself to begin the growth of the volume single crystal. In the adaptation step, the initial growth surface originating from an area disposed from a center to the central longitudinal axis considerably reduces in the growth direction towards an edge region. A growth surface of the seed crystal is formed in a convex-shaped-, conical- and truncated-cone shaped manner or is movably formed at the central longitudinal axis in a pyramid-like manner. A rear surface of the seed crystal turned away from the initial growth surface is formed in a flat-shaped manner, where a recess or a projection is provided at the rear surface. A crystallographic main axis of the seed crystal is oriented parallel to the central longitudinal axis of the seed crystal. The production of the volume single crystal takes place by a solution growth or a sublimation growth. The volume single crystal is produced as silicon carbide- or aluminum nitride volume single crystal in the form of mixed crystal made of elements of third, fourth and fifth main groups of the periodic system. An independent claim is included for a single crystal substrate.