Role of pO2 and film microstructure on the memristive properties of La2NiO4+δ/LaNiO3−δ bilayers

Altres ajuts: ICN2 is funded by the CERCA programme/Generalitat de Catalunya.LaNiO/LaNiO bilayers deposited at varying pO conditions resulted in remarkable differences in film microstructure and cell parameters, directly affecting the electrical behaviour of Pt/LaNiO/LaNiO/Pt devices. The devices deposited at low pO showed the largest memristance. We propose this is due to the formation of a p-type Schottky contact between LaNiO and LaNiO, where the extent of its carrier depletion width can be modulated by the electric-field induced drift of interstitial oxygen ions acting as mobile acceptor dopants in LaNiO

Parasitic oscillation in the low-frequency noise characterization of solar cells

International audienceThe analysis of low-frequency noise in solar cells is a very useful tool for defect characterization or understanding of fluctuation mechanisms in photodiodes. This type of noise characterization can however be limited by the presence of an undesired peak in the frequency spectra, caused by an oscillation in the measured current. It is shown in this work that this phenomenon originates in the interaction between the noise measurement system and the test structures of the solar cells, which usually introduce a high parasitic capacitance. Through experimental measurements, the link between the center frequency of the peak and the sensitivity of the noise measurement amplifier, as well as the solar cell surface area were explored. Finally, it is shown that, for characterization purposes, the oscillation peak could be pushed to higher frequencies by measuring smaller area cells or attenuated by choosing electrode shapes that enhance the device series resistance

Probing hidden conduction mechanisms in diced silicon solar cells by low frequency noise analysis

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Role of pO2 and film microstructure on the memristive properties of La₂NiO_4+<i>δ</i>/LaNiO_{3−<i>δ</i>} bilayers

International audienceLaNiO3/La2NiO4 bilayers deposited at varying pO 2 conditions resulted in remarkable differences in film microstructure and cell parameters, directly affecting the electrical behaviour of Pt/LaNiO 3 /La 2 NiO 4 /Pt devices. The devices deposited at low pO 2 showed the largest memristance. We propose this is due to the formation of a p-type Schottky contact between LaNiO 3 and La 2 NiO 4 , where the extent of its carrier depletion width can be modulated by the electric-field induced drift of interstitial oxygen ions acting as mobile acceptor dopants in La 2 NiO 4