RBS and ERDA characterisation of PZT ferroelectric layers

Full text: PZT layers [Pb(Zr,Ti)O3] have been largely investigated for their ferroelectric properties. This properties offer several advantages for non-volatile memory applications. The PZT layers were deposited on Pt/Ti/SiO2/Si electrodes using the sol-gel method. RBS (Rutherford Backscattering Spectrometry) and ERDA (Elastic Recoil Detection Analysis) techniques were used for the characterisation of the PZT layers. The RBS measurements were carried out at the Aramis Van den Graaff Tandem accelerator at CSNSM Orsay (France). The sample surface was perpendicular to the beam and the detector was placed at 165 angle with respect to the beam. He ions at 3.065 MeV were used. The energy spectrum of the backscattered ions is shown. The simulation of the energy spectrum plotted on the same graph was conducted using the code RUMP. The energy chosen for the He ions is close to a nuclear resonance energy of helium on oxygen. The resonance peak can be seen at channel 160. RBS and ERDA measurements were conducted at the Van den Graaff Tandem accelerator of NIPNE using 10B at 8 MeV for RBS and 28Si beam at 50 MeV for ERDA. For the ERDA measurement a ΔE(gas)-E(Si) telescope was placed at 30 angle with respect to the beam. The total energy spectrum of O is shown. The analysis of the spectra has been performed using our code SURFAN (the simulation is plotted on the same graph). Oxygen is coming from the PZT layer and from the SiO2 sublayer. The atomic ratio of the elements in the PZT layer is Pb0.96Zr0.33Ti0.60O3. This result is in good agreement with the RBS measurements. (author)