The density-functional theory (DFT) calculations are performed to examine the more complex energy signature of the wurtzite ferroelectric memory (FM) material AlScN with an aluminum, scandium, or nitrogen vacancy in various charge states. The model with an aluminum/ scandium vacancy discloses the smallest formation energy for n-type layers, and for the p-type layer, the model with a nitrogen vacancy reveals the lowest formation energy. The formation energy of the nitrogen-vacancy model is large for n-type cases, indicating that defects will not exist in large amounts. These results provide microscopic details that can pave a way for developing low-energy compact electronics.