Characterization of ultrathin Si02 films formed by direct low-energy ion-beam oxidation

Bombardment ofsilicon (100) stIrfaces at room temperature by an oxygen-containing low-energy ion beam is studied as an alternative to thermal oxidation to produce ultrathin oxide films. A self­ limiting oxide thickness of about 50 A is obtained by using ions with energy 100 eV or lower. Auger electron spectroscopy depth profiles of an ion-beam grown oxide and a thermally grown oxide show very similar composition. Grazing angle x-ray photoelectron spectroscopy indicates the presence oflower oxides ofsilicon near the surface. The capacitance-voltage characteristics of ion-beam grown oxides compare favorably with those of thermally grown oxides. .