Final answer:
Determining the donor impurity concentration in n-type silicon based on resistivity involves semiconductor physics principles, but the question lacks sufficient data for an exact calculation.
Step-by-step explanation:
The question concerns determining the donor impurity concentration in an n-type silicon semiconductor given the resistivity value at a certain temperature. Donor impurities in a semiconductor contribute free electrons to the conduction band, thus altering the electrical properties of the material, such as its resistivity. To find the donor impurity concentration, one would typically use the resistivity formula for a semiconductor, which involves the donor ionization energy, intrinsic carrier concentration, and other constants such as the charge of an electron and the material's permittivity. However, the provided information is not sufficient to calculate the exact concentration without additional data, like the mobility of electrons or the intrinsic carrier concentration of silicon at the given temperature. The explanation of impurity doping and its effect on semiconductors, such as n-type and p-type materials, is related to how semiconductors are engineered to have desired electrical properties through the introduction of impurities.