Influence of Reactive Ion Etching Applied to Si Substrate on Epitaxial Si Growth and Its Removal

The effects of post-etching treatments on Si selective epitaxial growth (SEG) have been studied. In the case of O 2 downflow treatment, SEG Si had dislocations and a rough surface. It was found that this abnormal growth was caused by SiO 2 formed by the post-etching treatment which could not be removed by diluted hydrogen fluoride (DHF) treatment prior to the SEG process. This SiO 2 was not removed due to the existence of carbon at the Si/SiO 2 interface which had been implanted by reactive ion etching (RIE). In the case of O 2 plasma treatment, there was no carbon at the Si/SiO 2 interface, SiO 2 was completely removed by DHF, and SEG Si was grown successfully. In conclusion, a new, low-temperature Si surface removal method with precise etching depth control using O 2 plasma treatment followed by DHF treatment is demonstrated to be an effective pretreatment for Si SEG.