  The quantum correction to the conductivity have been studied in two types of
2D heterostructures: with doped quantum well and doped barriers. The consistent
analysis shows that in the structures where electrons occupy the states in
quantum well only, all the temperature and magnetic field dependencies of the
components of resistivity tensor are well described by the theories of quantum
corrections. The contribution of electron-electron interaction to the
conductivity have been determined reliably in the structures with different
electron density. A possible reason of large scatter in experimental data
concerning the contribution of electron-electron interaction, obtained in
previous papers, and the role of the carriers, occupied the states of the doped
layers, is discussed.
