Interface-Engineered High-Mobility High-$k$/Ge pMOSFETs With 1-nm Equivalent Oxide Thickness

Effect of Annealing Ambient on Structural and Electrical Properties of Ge Metal-Oxide-Semiconductor Capacitors with Pt Gate Electrode and HfO<SUB>2</SUB> Gate Dielectric

“…It has been previously reported that defects in the dielectric layer and/or D it could be primary sources of frequency dispersion. [25][26][27] However, considering that the D it level in FG-annealed Si devices is approximately one order of magnitude lower than that of O 2 -annealed Ge devices, the imperfection of HfO 2 gate dielectric material such as oxygen vacancies is believed to be a main cause of the annealing ambient dependency of frequency dispersion in the C-V curves in present devices. Thus, O 2 annealing suppresses the formation of oxygen vacancies in the HfO 2 layer due to the oxygen-enriched region during thermal treatment.…”

Performance analysis of long Ge channel double gate (DG) p MOSFETs with high-k gate dielectrics based on carrier concentration formulation

“…Screening of literature was conducted for finding the practical range of variation in interface trap density in Ge MOSFETs with different high-k gate stacks. Our survey dictates that the interface trap charge density in the range 1 Â 10 11 -1 Â 10 13 eV À1 cm À2 would include the D it values for a variety of high-k/Ge interfaces and process conditions [36,37].…”

Challenges and opportunities in advanced Ge pMOSFETs

“…It is believed that fluorine segregates to the interface and passivates Ge dangling bonds, more effectively than forming gas annealing. In addition, bulk oxide traps are also passivated [148]. Peak low-field, long-channel effective hole mobilities of 396 cm 2 /Vs have been obtained in this way.…”

“…This should make the thin GeO 2 interfacial layer more robust against the deposition of the high-k layer. In addition, encouraging results have been achieved by pre-gate GeO 2 surface passivation by thermal oxidation at 400 1C, followed by a post-gate F treatment in a CF 4 plasma [148]. The final step is a Post Deposition Anneal (PDA) at 500 1C for 30 s. A reduction of the D it by a factor of 3 has been found both in the upper and lower half of the band gap, compared with no fluorine treatment [148].…”

“…In addition, encouraging results have been achieved by pre-gate GeO 2 surface passivation by thermal oxidation at 400 1C, followed by a post-gate F treatment in a CF 4 plasma [148]. The final step is a Post Deposition Anneal (PDA) at 500 1C for 30 s. A reduction of the D it by a factor of 3 has been found both in the upper and lower half of the band gap, compared with no fluorine treatment [148]. It is believed that fluorine segregates to the interface and passivates Ge dangling bonds, more effectively than forming gas annealing.…”