Abstract
The structure, interfacial nanochemistry, and electrical properties of sol-gel derived Pb(Zr0.3Ti0.7)O3 or PZT (30 / 70) thin films on metal-organic chemical vapor deposited (0001) GaN/sapphire substrates are reported. The X-ray diffraction analysis confirmed a phase-pure and highly oriented (111) PZT and Rutherford backscattering spectroscopy was used to ascertain the Zr/Ti ratio. The secondary ion mass spectrometry depth profile and electron energy loss spectroscopy with high energy and spatial resolution indicated a chemically sharp PZT/GaN interface with insignificant interdiffusion between Pb, Zr, or Ti in PZT and Ga and N in GaN. The lower capacitance density (C / A = 0.35 μF/cm2) and asymmetrical polarization (P ∼ 4 μC/cm2) hysteresis loops of PZT in Pt/PZT/GaN or metal-ferroelectric-semiconductor configuration were attributed to the high depolarization field (Edepol) within PZT. In contrast, PZT in Pt/PZT/Ru/GaN or metal-ferroelectric-metal configuration exhibited high capacitance density (C / A = 1.25 μF/cm2) and polarization (P ∼ 30 μC/cm2).
Original language | English (US) |
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Pages (from-to) | 154-159 |
Number of pages | 6 |
Journal | Thin Solid Films |
Volume | 484 |
Issue number | 1-2 |
DOIs | |
State | Published - Jul 22 2005 |
Keywords
- EELS
- GaN
- Interfaces
- Pb(Zr, Ti)O
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Metals and Alloys
- Materials Chemistry