Characterization of Al-Based High-k Stacked Dielectric Layers Deposited on 4H-SiC by Atomic Layer Deposition

Muhammad Usman; T. Pilvi; Markku Leskelä; Adolf Schöner; Anders Hallén

doi:10.4028/www.scientific.net/MSF.679-680.441

Paper Titles

Improved MOS Interface Properties of C-Face 4H-SiC by POCl₃ Annealing
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Theoretical Studies for Si and C Emission into SiC Layer during Oxidation
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3C-SiC MOS Based Devices: From Material Growth to Device Characterization
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Formation of Periodic Steps on 6H-SiC (0001) Surface by Annealing in a High Vacuum
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Characterization of Al-Based High-k Stacked Dielectric Layers Deposited on 4H-SiC by Atomic Layer Deposition
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Improved Characteristics of SiC MOSFETs by Post-Oxidation Annealing in Ar at High Temperature
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Comparative Study on Metallization and Passivation Materials for High Temperature Sensor Applications
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Schottky Contacts to N-Type 4H-SiC Fabricated with Ti-, Mo-, Ni- and Al-Based Metallizations
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Graded Etched Junction Termination for SiC Thyristors
p.457

HomeMaterials Science ForumMaterials Science Forum Vols. 679-680Characterization of Al-Based High-k Stacked...

Characterization of Al-Based High-k Stacked Dielectric Layers Deposited on 4H-SiC by Atomic Layer Deposition

Abstract:

Aluminum-based high-k dielectric materials have been studied for their potential use as passivation for SiC devices. Metal-insulator-semiconductor structures were prepared and their dielectric properties were analyzed using capacitance-voltage and current-voltage measurements. Atomic layer deposition was used for the deposition of dielectric layers consisting of AlN with or without a buffer layer of SiO2, and also a stack of alternating AlN and Al2O3 layers. It has been observed that AlN has a polycrystalline structure which provides leakage paths for the current through the grain boundaries. However, adding alternate amorphous layers of Al2O3 prevent this leakage and give better overall dielectric properties. It is also concluded that the breakdown of the dielectric starts from the degradation of the thin interfacial SiO2 layer.