A wavelength resolved thermally stimulated luminescence (TSL) study ha
s been carried out for the first time on X-irradiated chemical vapor d
eposition SiO2 films deposited on a silicon substrate, from room tempe
rature, to 400 degrees C. Upon irradiation, the TSL glow curve feature
s a prominent structure at a maximum temperature, T-max, of approximat
ely 62 degrees C (heating rate = 1 degrees C/s); the analysis of the e
mission wavelength shows a peak at 457 nm (2.71 eV). The shape of the
TSL peak is complex, and cannot be described in the frame of classical
first- or second-order kinetics. Moreover, T-max has a strong and mon
otonic shift to higher temperatures after partial pre-heating treatmen
ts while the spectral emission is not modified: a similar phenomenon h
as already been observed in bulk fused silica of various types, differ
ent from crystalline quartz which does not present any shift of T-max
as a function of pre-heating. These results suggest that the TSL peak
is characterized by a distribution of trap parameters: specifically, a
continuous distribution of trap energy or of the frequency factor can
be taken into account. Considerations on the characteristics of the t
rap parameter distribution are made.