A process for producing a single-crystal silicon wafer, comprises the
following steps: producing a layer on the front surface of the silicon
wafer by epitaxial deposition or production of a layer whose electrical
resistance differs from the electrical resistance of the remainder of the
silicon wafer on the front surface of the silicon wafer, or production of
an external getter layer on the back surface of the silicon wafer, and
heat treating the silicon wafer at a temperature which is selected to be
such that an inequality (1)
.times..times.<.times..times..times..times..times..times..times..sigma-
..times..times..OMEGA..times..times..times..times. ##EQU00001## is
satisfied, where [Oi] is an oxygen concentration in the silicon wafer,
[Oi].sup.eq(T) is a limit solubility of oxygen in silicon at a
temperature T, .sigma..sub.SiO2 is the surface energy of silicon dioxide,
.OMEGA. is a volume of a precipitated oxygen atom, r is a mean COP radius
and k the Boltzmann constant, with the silicon wafer, during the heat
treatment, at least part of the time being exposed to an
oxygen-containing atmosphere.