Dry and Wet Processed Interface Layer in Ge/High-K Devices studied by Deep Level Transient Spectroscopy

摘要

Dry and wet processed interface layer quality of Ge/high-k MOS structures were studied by deep level transient spectroscopy (DLTS). The interface treatments were: (ⅰ) simple chemical oxidation (Chemox); (ⅱ) chemical oxide removal (COR) followed by 1 nm oxide by slot-plane-antenna (SPA) plasma (COR&SPAOx); and (ⅲ) COR followed by vapor O_3 treatment (COR&O3). By conducting deep level transient spectroscopy (DLTS) on these three samples, it is found that the dry processed interface (COR&SPAOx and COR&O3) shows a majority slow trap which was not observed in wet processed interface treatment (Chemox). This results clearly suggest that formation of a different type of interfacial GeOx is responsible for the the additional defect type in dry processed devices.