Electron Band Alignment at Interfaces of Semiconductors with Insulating Oxides: An Internal Photoemission Study

<table>Square root of the PC yield as a function of photon energy in Si/SiO<sub>2</sub>/Lu<sub><i>x</i></sub>Al<sub>1−<i>x</i></sub>O<sub>3</sub>/Au capacitors with different concentration of lutetium in the insulating layer as measured under positive (a) and negative (b) bias of 2 V applied to the top Au electrode. The results are shown both for the as-deposited samples as for those supplementally annealed at 1000°C in N<sub>2</sub> for 1 min prior to metallization. The inferred spectral thresholds of the intrinsic PC are indicated by vertical lines <svg height="18.362499" id="M121" style="vertical-align:-5.76984pt" version="1.1" viewbox="0 0 18.262501 18.362499" width="18.262501" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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Advances in Condensed Matter Physics

fig13

Figure 13

Figure 13: Electron Band Alignment at Interfaces of Semiconductors with Insulating Oxides: An Internal Photoemission Study 