Gold‐silicon interfaces have been studied under ultrahigh vacuum conditions. The interface growth, its characterization by Auger electron spectroscopy, and its irradiation by low‐energy (1–3 keV) electrons have all been carried outinsitu. We have estimated the adhesion of the gold layer by the peeling test. The adhesion is good when Au is deposited on a clean Si substrate and poor when a native oxide (thickness ∼10–15 A˚) is present at the interface. We show that the electron irradiation decomposes the oxide partially and this produces a drastic increase of the adhesion. The oxide decomposition is not thermally induced and is attributed to electronic effects. We suggest that the formation of Au–Si bonds at the interface is at the origin of the adhesion enhancement.