The spectrometric characteristics of detectors based on 4H-SiC ﬁlms with ion-doped p+–n junctions in a temperature range from 25 to 375 °C have been studied. The experiments with 5.8-MeV α-particles in a high-temperature chamber were performed. The interference factors of the detectors operation in a mode of spectrometry are established. The energy resolution of 1.35% is received. An increase of the efﬁciency of the diffusion–drift charge transport with increasing temperature has been observed. The last is explained by an increase in the diffusion length of minority carriers.