Characterization of Aluminum and Titanium Oxides Deposited on 4H SiC by Atomic Layer Deposition Technique

摘要

Aluminium oxide and titanium oxide films were deposited using the Atomic Layer Deposition method on n-type 4H SiC and p-type Si {001} substrates, with doping 6 · 10~(15) cm~(-3) and 2·10~(16) cm~(-3), respectively, and on 1.2 kV PiN 4H SiC diodes for passivation studies. The Al_2O_3 and SiC interface was characterised for the existence of an effective negative charge with a density of 1 · 10~(12)-2·10~(12) cm~(-2). The dielectric constant of Al_2O_3 as determined from capacitance-voltage data was about 8.3. The maximum electric field supported by the Al_2O_3 film was up to 7.5 MV/cm and 8.4 MV/cm on SiC and Si, respectively.