In this study, a first detailed comparison of the spectral responsivity and internal quantum efficiency (IQE) of 4H-SiC UV sensors with ion implanted and epitaxially grown p-emitter is presented. Additionally, an analytical device model is implemented. It is evident that radiation damage and defects produced during the ion implantation and subsequent annealing are mainly responsible for the approximately 10% lower IQE for wavelengths smaller than 280 nm. In the device model, these defects correspond to a lower effective minority carrier diffusion length within the p+-emitter for the ion implanted devices. Nevertheless, both emitter technologies are suitable in order to achieve a high sensor performance (peak IQE > 60%).