Dh. Kwak et al., EFFECT OF RAPID THERMAL ANNEALING ON THE INTERFACE-TRAP DENSITY BETWEEN PT AND (BA,SR)TIO3 THIN-FILM, Integrated ferroelectrics, 17(1-4), 1997, pp. 179-186
We determined the electron density trapped at the Pt/BST interface in
Pt/(Ba,Sr)TiO3/Pt MIM capacitor. The electron densities trapped at the
top-Pt/BST interface and the bottom-Pt/PST interface were calculated
to be constant (2 similar to 3 x 10(12) cm(-2)) for all the as-deposit
ed films of varying thicknesses. Rapid thermal annealing (RTA) was att
empted to reduce the interface trapped electron density of MIM capacit
or. The MIM capacitors were post-annealed at 650 degrees C for 30 seco
nds in oxygen and nitrogen atmosphere. As a result, the trapped electr
on densities were reduced to one third compared with those of the as-d
eposited samples. And leakage current density of the annealed samples
also decreased drastically. So the rapid thermal annealing process is
thought to be very effective in reducing leakage current densities of
BST MIM capacitors.