Study of electrical properties of Al/SrTiO3/n-Si interfaces using capacitance measurements

Electrical properties of Al/SrTiO
₃
/n-Si, metal-insulator-semiconductor (MIS) structure have been carried out by employing capacitance measurements. Thin films of SrTiO
₃
having thicknesses 50, 30 and 15 nm were grown on n-Si (N
_D
= (2-10) times 10
¹⁵
cm
^-3
) by metal organo-chemical vapor deposition (MOCVD). Effective dielectric constant (k) of SrTiO
₃
was found to be much lesser than the theoretical value (~300) and fluctuated with layer thickness in the range of 95 to 32. The observed decrease in dielectric constant has been explained on the basis of two layer model. Annealing under specific ambient has improved the dielectric properties of the samples. This paper contributes as the enabling technologies in the area of optoelectronic components fabrication for communications.