Title :
Effect of Al inclusion in HfO2 on the physical and electrical properties of the dielectrics
Author :
Zhu, W.J. ; Tamagawa, T. ; Gibson, M. ; Furukawa, T. ; Ma, T.P.
Author_Institution :
Yale Univ., New Haven, CT, USA
Abstract :
This authors present the effect of Al inclusion in HfO/sub 2/ on the crystallization temperature, leakage current, band gap, dielectric constant, and border traps. It has been found that the crystallization temperature is significantly increased by adding Al into the HfO/sub 2/ film. With an addition of 31.7% Al, the crystallization temperature is about 400-500/spl deg/C higher than that without Al. This additional Al also results an increase of the band gap of the dielectric from 5.8 eV for HfO/sub 2/ without Al to 6.5 eV for HfAlO with 45.5% Al and a reduced dielectric constant from 19.6 for HfO/sub 2/ without Al to 7.4 for Al/sub 2/O/sub 3/ without Hf. Considering the tradeoff among the crystallization temperature, band gap, and dielectric constant, we have concluded that the optimum Al concentration is about 30% for conventional self-aligned CMOS gate processing technology.
Keywords :
CMOS integrated circuits; MOSFET; aluminium; crystallisation; dielectric thin films; energy gap; hafnium compounds; leakage currents; permittivity; semiconductor-insulator boundaries; 400 to 500 degC; 6.5 eV; Al inclusion; HfAlO; HfO/sub 2/; HfO/sub 2/ dielectric film; band gap; border traps; crystallization temperature; dielectric constant; high-k dielectrics; leakage current; self-aligned CMOS gate processing technology; CMOS technology; Crystallization; Dielectric constant; Hafnium oxide; High-K gate dielectrics; Leakage current; Photonic band gap; Rapid thermal annealing; Temperature; X-ray scattering;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2002.805000
