Purpose: The suitability of two possible detectors, silicon and germanium as the Compton camera’s first plane detector has been investigated using a robust Monte Carlo approach. Methods: The GEANT4 simulation software was used to simulate the radiation transport and interactions with matter. Investigations were first done by relating the impact of Doppler broadening on the Compton camera angular uncertainty, energy spectra and reconstructed source image. Then, the impact of geometry and interaction type on the Compton camera performance was evaluated as well. Results: Analyses suggest that silicon of about 1 cm thickness would be suitable as the Compton camera first plane detector. The choice of silicon is however not completely flawles...