Influence of dry etching on the properties of SiO2 and HfO2 single layers

A comparative study was performed to investigate how etching methods and parameters affect the properties of S i O 2 and H f O 2 coatings. S i O 2 and H f O 2 single layers were prepared by electron-beam evaporation (EBE), ion-beam assisted deposition (IAD), and ion-beam sputtering (IBS). Then, ion-beam etching (IBE), reactive ion etching (RIE), and inductively coupled plasma etching (ICPE) were used to study the influence of ion bombardment energy and chemical reaction on the etching rates and properties of the prepared S i O 2 and H f O 2 single layers. For S i O 2 coatings, chemical reaction plays a dominant role in determining the etching rates, so ICPE that has the strongest C H F 3 plasma shows the highest etching rate. Moreover, all three etching methods have barely any influence on the properties of S i O 2 coatings. For H f O 2 coatings, the etching rates are more dependent on the ion bombardment energy, although the chemical reaction using C H F 3 plasma also helps to increase the etching rates to some extent. To our surprise, the ion bombardment with energy as high as 900 V does not change the amorphous microstructure or crystalline states of prepared H f O 2 coatings. However, the high-energy ion bombardment in IBE significantly increases the absorption of the H f O 2 coatings prepared by all deposition techniques and decreases their laser damage resistance to different extents.