Buried GaSb junctions were induced in Te‐doped GaSb bulk crystals by growing a heavily Zn‐doped GaAs layer on GaSb. However, the p‐n junction resulted to be located much more deeply with respect to the Zn diffusion front and originated by a local rising up of native acceptor density, which controls the p‐type conductivity conversion of the GaSb substrate for about 1 μm beyond the Zn penetration depth. Admittance spectroscopy measurements supported the identification of such defects with the double native acceptor GaSb. Current‐voltage characteristics of the p‐n junction, performed after the removal of the GaAs layer, were here analyzed as a function of the temperature for different Zn doping levels and resulted consistent with the model previously proposed to explain the formation of the junctions.