The Impact of Chemical-Mechanical Polishing on Defective 4H-SiC Schottky Barrier Diodes

Kung Yen Lee; Wen Zhou Chen; Michael A. Capano

doi:10.4028/www.scientific.net/MSF.600-603.827

Paper Titles

Characteristics of Sol-Gel Derived SiO₂Thick Film on 4H-SiC
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New Chemical Planarization of SiC and GaN Using an Fe Plate in H₂O₂ Solution
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Development of Lapping and Polishing Technologies of 4H-SiC Wafers for Power Device Applications
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Improvements in Electrical Properties of SiC Surface Using Mechano-Chemical Polishing
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The Impact of Chemical-Mechanical Polishing on Defective 4H-SiC Schottky Barrier Diodes
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Effect of Process Parameters on Material Removal Rate in Chemical Mechanical Polishing of 6H-SiC(0001)
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Damage-Free Planarization of 2-Inch 4H-SiC Wafer Using Pt Catalyst Plate and HF Solution
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The Preparation of World-Class Single Crystal Silicon Carbide Wafers Using High Rate Chemical Mechanical Planarization Slurries
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Beveling of Silicon Carbide Wafer by Plasma Chemical Vaporization Machining
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HomeMaterials Science ForumMaterials Science Forum Vols. 600-603The Impact of Chemical-Mechanical Polishing on...

The Impact of Chemical-Mechanical Polishing on Defective 4H-SiC Schottky Barrier Diodes

Abstract:

In this article, the correlation of surface morphological defects and barrier-height inhomogeneities with the electrical characteristics of defective 4H-SiC Schottky barrier diodes (SBDs) before and after chemical-mechanical polishing (CMP) is investigated. The forward characteristics, an ideality factor and a single barrier height of a SBD, remain the same after CMP, so that CMP does not affect SBD characteristics. Most barrier-height inhomogeneities are eliminated or improved after CMP. Therefore, leakage current induced by barrier-height inhomogeneities are improved by CMP as well. In addition, about 40% of SBDs with carrots inside the active areas exhibits double barriers before CMP. This excludes that carrots are a cause of barrier-height inhomogeneities. In reverse-bias mode, CMP reduces reverse leakage current at low bias and increases breakdown voltage due to the reduction of thermionic field emission and elimination of local enhanced electric fields.