At absolute zero temperature, all atoms in a material are in their lowest energy state, also known as the ground state. In this state, the electrons fill up energy levels according to the Pauli exclusion principle, which states that no two electrons can occupy the same quantum state.

One important concept in solid-state physics is the Fermi energy level. The Fermi energy level represents the highest energy level occupied by electrons at absolute zero temperature. It separates the filled states, known as the valence band, from the empty states, known as the conduction band.

In the case of donors, which are impurity atoms with extra electrons in the crystal lattice, the donor energy level is below the conduction band. These extra electrons are loosely bound to the donor atoms and can easily be excited to the conduction band by thermal or optical energy. Therefore, the donor energy level is not above the Fermi energy level.

Similarly, the acceptor energy level, which is associated with impurity atoms that have fewer electrons than the host atoms, is also not above the Fermi energy level. The acceptor energy level is typically located within the band gap, closer to the valence band.

On the other hand, the conduction band represents the energy levels that are empty at absolute zero temperature. Electrons in the conduction band are free to move and contribute to electrical conductivity. Since the Fermi energy level separates the filled states from the empty states, in the case of donors, the conduction band is above the Fermi energy level.

Therefore, at absolute zero temperature, the level above the Fermi energy level in the case of donors is the conduction band.

To summarize:
- Donor energy level: Below the conduction band
- Acceptor energy level: Located within the band gap, closer to the valence band
- Conduction band: Above the Fermi energy level (in the case of donors)