The influence of shallow background donor impurities on the energy characteristics of the SiGe/Si/SiGe quantum well structure with centered delta-doping is studied numerically. The description of the self-consistent method includes the calculation of the donors impurity binding energy in the delta-layer. The delta-layer impurity binding energy as well as the energy differences between the first quantized electron subbands in the well demonstrate a significant dependence on the characteristics of the background doping. Therefore, the background doping cannot be neglected when studying phenomena like intersubband optical transitions. © 2019 IOP Publishing Ltd.