Role of the emitted Si atom due to oxidation-induced strain during very thin oxide decomposition on Si(001) studied by RHEED combined with AES

Ogawa, Shuichi*; Yoshigoe, Akitaka ; Ishizuka, Shinji*; Teraoka, Yuden; Takakuwa, Yuji*

To verify the unified model of Si oxidation reactions mediated by point defects generation (emitted Si atoms + vacancies) due to oxidation-induced strain, which is also applicable to void nucleation reactions during oxide decomposition, RHEED combined with AES was employed to monitor simultaneously the oxide coverage and interfacial roughness during void nucleation and growth in the oxide decomposition on Si(001). By the RHEED-AES measurements, not only the void nucleation time but also the void growth time by the complete oxide removal are considerably elongated as the second oxide layer coverage increases. From these results, it is found that the oxide decomposition by emitted Si atoms due to the oxidation-induced strain at SiO/Si interface, which is a rate-limiting reaction of void nucleation, takes place frequently even after void nucleation.