In the field of radiation physics, the study and measurement of the gamma-ray energy emitted from radionuclides are very important, and have many applications in different fields of sciences such as in the study of nuclear structure, the identification of radioisotopes and their activities, estimating absorbed dose, and the determination of interaction cross- sections, in which gamma-rays are either incident or outgoing from the reaction. Newly, developments in gamma-ray spectrometry have expanded and have been applied in diverse fields such as astrophysics and medical therapy for which highly accurate measurements of gamma-rays are needed. This has been achieved by way of tracing the interaction of gamma-rays in the semiconductor and scintillation detectors and the energy deposited within.