The anisotropy Delta S of the thermopower in thin films of the high-T-
c superconductor Bi2Sr2CaCu2O8 is investigated using off-c-axis epitax
ial film growth and the off-diagonal Seebeck effect. The measurements
represent a new method for the investigation of anisotropic transport
properties in solids, taking advantage of the availability of oriented
grown crystalline thin films instead of using bulk crystals. First re
sults for the temperature dependence Delta S(T) in Bi2Sr2CaCu2O8 thin
films are presented and described within a two-band model. Subjecting
the films to heat treatments in different gases at relatively low temp
eratures, Delta S could reversibly be changed in a wide range.