Spray-coated SiO2Thin Film for Passivation of n-type Cz Silicon Surface with Seff~6 cm-sec

An industrially viable spray-coating technique is demonstrated for silicon dioxide (SiO
₂
) thin film deposition to passivate n-type silicon surface. SiO
₂
films of ~10 nm thickness are deposited. XPS analysis reveals nearly stoichiometric film. An effective surface recombination velocity (S
_eff
) of 8 cm sec
^-1
and 6 cm sec
^-1
is achieved on n-type Czochralski silicon after aluminum anneal (alneal) and forming gas annealing (FGA) processes, respectively without any capping layer. Low S
_eff
values are explained using interface state density (D
_it
) and fixed oxide charge density (Qf) extracted from conductance-voltage and capacitance-voltage characteristics of fabricated metal-oxide-semiconductor capacitors. In case of FGA, field-effect passivation is dominant, whereas chemical passivation is dominant in case of alneal.