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Baking (Pb, La)(Zr, Ti)O3 capacitors in a hydrogen atmosphere causes a significant loss of remanent polarization even at 150 °C. The hysteresis variations depend on the polarization states during baking. The hysteresis loop showed voltage shifts when the capacitor was polarized before baking, whereas it became a cramped shape when the baking was carried out on a virgin capacitor. Although remanent polarization diminished in all cases, saturation polarization was not suppressed. The clamped hysteresis loop can be described as an average of two loops shifted to positive and negative voltages. The results indicate that the loss of remanent polarization is not due to the suppression of switching, but due to the shift of the hysteresis of each domain larger than the coercive voltage.

Photoluminescence (PL) decay for as‐prepared and dry‐oxidized porous Si following by a nitrogen pulse laser excitation is reported. The PL decay of both samples is nonexponential. For the as‐prepared samples, the PL lifetime decreases from 200 to 60 μs as the PL emission energy increases from 1.55 to 1.90 eV. The spread in values can be interpreted in terms of nonradiative tunneling of carriers between Si microcrystals. For the dry‐oxidized samples, the PL lifetime depends little on the emission energy, and is about 100 μs. On the basis of these results, we conclude that photoluminescence cannot be explained by the tunneling model alone, suggesting that luminescence centers play a role in determining the PL mechanism of porous Si.

The authors investigated the data retention properties of NiOy resistors exposed to sputtered particles and found that they depended on the bias polarity used to program the data. Only the data in the high resistance state programmed by applying positive bias to the top electrode were easily damaged. This suggests that the “reset” process can take place when the anodic side of the conductive filaments, which were formed during the “forming” process, is insulated. In addition, the data retention test for thermal stress suggests that the reset process can take place thermally.