Hot subdwarfs are core helium-burning stars at the extreme horizontal branch, characterized by an extremely thin hydrogen envelope. they are generally divided into B-type hot subdwarf stars (sdBs) and O-type hot subdwarf stars (sdOs) according to their spectral features. SdBs typically have effective temperatures between 20,000K and 40,000K, while sdOs have effective temperatures between 40,000K and 80,000K, and are generally more luminous than sdBs.A significant portion of hot subdwarfs are found in close binary systems with white dwarfs or low-mass main-sequence companions, suggesting that they might form through binary interaction processes. Three primary binary evolution channels have been proposed to produce hot subdwarfs: the common envelope ejection channel, the stable Roche lobe overflow channel, and the double white dwarf merger channel.The chemical properties of most hot subdwarfs are quite peculiar, most notably the abnormal surface helium abundance, which may be caused by atomic diffusion effects. Based on the surface helium abundance, hot subdwarfs can be classified into helium-rich and helium-poor types. Helium-rich hot subdwarfs can further be divided into extreme helium-rich and intermediate helium-rich stars. The origin of intermediate helium (He)-rich hot subdwarfs are still unclear. Previous studies have suggested that some surviving Type Ia supernovae (SNe Ia) companions from the white dwarf~+~main-sequence (WD+MS) channel may contribute to the intermediate He-rich hot subdwarfs. However, previous studies ignored the impact of atomic diffusion on the post-explosion evolution of surviving companion stars of SNe Ia, leading to that they could not explain the observed surface He abundance of intermediate He-rich hot subdwarfs. In this work, by taking the atomic diffusion and stellar wind into account, we trace the surviving companions of SNe Ia from the WD+MS channel using the one-dimensional stellar evolution code \textsc{MESA} until they evolve into hot subdwarfs. We find that the surface He-abundances of our surviving companion models during their core He-burning phases are in a range of $-1 \lesssim {\rm log}(N_{\rm He}/N_{\rm H}) \lesssim 0$, which are consistent with those observed in intermediate He-rich hot subdwarfs. This seems to further support that surviving companions of SNe Ia in the WD+MS channel are possible to form some intermediate He-rich hot subdwarfs.
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