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In this work we studied the preparation, structure and properties of Ta2O5 films grown by sol-gel method. The specimems were prepared byspin-coating the starting solution containing Ta(OC2H5)5 onto Si wafersfollowed by various heat treatments. X-ray and AES analyese indicted atthe film has [O]/ [Ta] ratio rather close to exact stoichiometry. The films annealed at 400℃for 4hrs exhibited the highest dielectric constant (24.27) and the best breakdown voltage (1.23MV/cm). However, as revealed by TEM, SEM and AFM characterizations, the Ta2O5 films prepared by sol-gelmethod contained many micro- defects and voids which severely restricted their electrical performance. Recrystallization during further annealsinduced even more defects in Ta2O5 films, which showed no benefication of both structure and electrical properties of the films.
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