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Abstract: We report the effect of annealing on electrical and physical characteristics of HfO2, HfSi x O y and HfO y N z gate oxide films on Si. Having the largest thickness change of 0.3nm after post deposition annealing (PDA), HfO y N z shows the lowest leakage current. It was found for both as-grown and annealed structures that Poole–Frenkel conduction is dominant at low field while Fowler–Nordheim tunneling in high field. Spectroscopic ellipsometry measurement revealed that the PDA process decreases the bandgap of the dielectric layers. We found that a decreasing of peak intensity in the middle HfO y N z layer as measured by Tof-SIMS may suggest the movement of N toward the interface region between the HfO y N z layer and the Si substrate during the annealing process. [Copyright &y& Elsevier]

Abstract: The effect of the deposition temperature and layer thickness on the physical and electrical properties of ZrO2-based high-k metal–insulator–metal (MIM) capacitors was studied. The increasing thickness of ZrO2 layer leads to decreasing the leakage current and capacitance of the device. The microstructure investigation shows that after the deposition of the complete MIM stack layer, all samples reveal similar degree of crystallinity, independent of the dielectric deposition temperature, hence it cannot explain completely the different electrical performance of the device. We found that the impurities concentration in the stack decreases as the deposition temperature increases. As a result, we obtain low leakage current (<10− 8 A/cm2) with highest k value(~43) for 8 nm ZrO2 layer deposited at a temperature of 275 °C. [Copyright &y& Elsevier]

Wet etching(LSCMO) films on Bi4Ti3O12/CeO2/yttrium-stabilized zirconia (YSZ)-buffered Si substrates was investigated using potassium hydroxide (KOH) and buffered hydrofluoric acid (BHF) solutions. X-ray diffraction (XRD) and scanning spreading resistance microscopy (SSRM) measurements revealed that the morphological roughness of the LSCMO films increases, while the electrical resistance roughness decreases, with increasing KOH etching time. The LSCMO films are highly chemically resistant to KOH solution; however, in the case of BHF etching, an etch rate of 22 nm/min was obtained with high selectivity over a photoresist mask. [ABSTRACT FROM AUTHOR]

Antimony ions were implanted into SiO2/Si substrates at energies of 30 and 50 keV at relatively low doses (max. 5×1015 ions cm-2). The behaviour of the implanted ions was simulated with a dynamic TRIM code, allowing treating alteration of the target in a dynamic mode, i.e. as a function of ion dose. For cases, where the projected range of the implant coincides with the interface, it has been observed that there is significant mixing between the SiO2 layer and the Si substrate together with a constant value for the O/Si ratio except for a pronounced oxygen surface peak. Whereas in the cases, where the implant is far from the interface, the O/Si ratio shows characteristic oscillations together with the surface peak. For high doses, above about 1016 ions cm-2, a gradual increase of the sputtering yield of SiO2 is observed due to Sb incorporation in the substrate. The balance between the sputtering and swelling of the target is shown to be negative up to a fluence of 9.5×1015 ions cm-2, although the total sputtering yield is more than 1. RBS (Rutherford Backscattering Spectrometry) measurements confirm the mixing at the interface in cases where the latter coincides with the projected range of the implanted ions. [ABSTRACT FROM AUTHOR]

Antimony nanocrystals were formed in thin SiO2 films using low-energy ion implantation of Sb followed by annealing. Using Fourier transform laser microprobe mass spectrometry (FT LMMS), we observed for the first time the presence of antimony oxide in the intermediate phase (as-implanted layer of Sb) by means of signals referring to the intact Sb2O3 molecules. Only SbO+ fragments, but no adduct ions of Sb2O3 could be detected in annealed samples. The size and the distribution of the nanocrystals formed around the initial depth of implantation were studied in the as-implanted samples by high-resolution electron microscopy (HREM). The crystalline structure of these nanocrystals was also studied and the presence of antimony trioxide Sb2O3 in the form of valentinite was proven. After the annealing step, the implanted material had spread into a wider band. The method introduced here, based on combining TEM (transmission electron microscopy) and FT LMMS results, offers the possibility of studying the evolution of the phases in Sb nanocrystal formation. [ABSTRACT FROM AUTHOR]