HfO 2 -based gate stacks with titanium (Ti) incorporated into a GeO x interfacial layer (IL) were fabricated on p-Ge substrates. X-ray photoelectron spectroscopy results, incorporating Ti, can efficiently suppress the GeO volatilization. This contributed to achievement of an equivalent oxide thickness of approximately 0.8 nm, a low interface states density Dit of approximately 2.5 ×,1011 eV - 1 cm - 2, and a smaller Dit increment of approximately 1 × 1011eV-1 cm -2 after constant negative voltage stress at a field of 8 MV/cm. Therefore, Ti is appropriate for improving the quality of GeO x through high temperature annealing.
- Constant voltage stress (CVS)
- germanium oxide (GeO )
- hafnium oxide (HfO )
- titanium (Ti)