The generation of interface states and oxide electron traps in thermal sili
con dioxide (SiO2) lavers by sputtering metallization has been investigated
. The dependence of the samples on electric field and temperature during th
e sputter process is observed. The interface state density spectra revealed
narrow distributions indicating an increased density of band edge states.
In the upper part of the Si band gap a peak was observed due to the generat
ion of a particular interface defect site. Three bulk defect centers were f
ound as identified by their capture cross sections of the order of 1 x 10(-
16), 3 x 10(-17) and 3 x 10(-18) cm(2). The first one is associated with ra
diation induced neutral centers and is a feature of oxides metallized by sp
uttering. The other two traps are believed to be related to defects like Si
OH and H2O, Post metallization annealing (PMA) resulted in a reduction of t
he density of the oxide and interface traps and a broadening of the interfa
ce trap spectra, A speculation on the defect formation process is included.