Assessment of Energy Barriers Between ZrCuAlNi Amorphous Metal and Atomic Layer Deposition Insulators Using Internal Photoemission Spectroscopy

作者：Jenkins, Melanie A.; Klarr, Tyler; Austin, Dustin Z.; Li, Wei; Nguyen, Nhan V.; Conley, John F., Jr.^*

来源：Physica Status Solidi-Rapid Research Letters, 2018, 12(3): 1700437.

DOI：10.1002/pssr.201700437

• barrier height
• capacitors
• internal photoemission
• metal-insulator-metal structures
• tunnel diodes

The energy barrier heights between an ultra-smooth amorphous metal electrode, ZrCuAlNi, and several atomic layer deposited (ALD) insulators are measured using internal photoemission (IPE) spectroscopy. ZrCuAlNi-insulator barriers are characterized within metal-insulator-metal (MIM) stacks with Al top contacts and results are compared with the Al/insulator barrier heights. The measured barrier heights at the ZrCuAlNi interface are found to be 3.3, 3.2, 3.0, and 2.2eV for SiO2, Al2O3, HfO2, and ZrO2, respectively. This barrier height trend is consistent with the electron affinity of the respective oxides. However, barriers for SiO2 and Al2O3 are smaller than that ideally expected based on the reported vacuum work function of ZrCuAlNi, indicating a smaller ZrCuAlNi effective work function in these device structures. The measured Al barrier height results confirm previous reports of a negative dipole at the Al-ALD insulator interface.

• 出版日期2018-3