High Hall electron mobility in the inversion layer of 4H-SiC (0001)/SiO₂ interfaces annealed in POCl₃

Hall effect measurements were conducted for MOSFETs with and without post-oxidation-annealing (POA) fabricated on the p-body doping in a wide doping range to vary the effective normal field (E (eff)). The Hall mobility (& mu; (Hall)) in the high-E (eff) region of the MOSFETs annealed in phosphoryl chloride (& mu; (Hall) = 41 cm(2) V-1 s(-1) at E (eff) = 1.1 MV cm(-1)) is much higher than that of MOSFETs annealed in nitric oxide (NO) (& mu; (Hall) = 14 cm(2) V-1 s(-1) at E (eff) = 1.1 MV cm(-1)), suggesting that the trapped electrons act as strong Coulomb scattering centers for the MOSFETs annealed in NO and without POA.