Experimental analysis of I‐V and C‐V characteristics of Ni/SiO₂/4H‐SiC system with varying oxide thickness

Abstract

Purpose

The purpose of this paper is to electrically examine the quality of thin thermally grown SiO₂ with thickness variation, on Si‐face of 4H‐SiC <0001> (having 50 μm epitaxial layer) by current‐voltage (I‐V) and capacitance‐voltage (C‐V) methods.

Design/methodology/approach

Metal‐oxide‐silicon carbide (MOSiC) structures with varying oxide thickness have been fabricated on device grade 4H‐SiC substrate. Ni has been used for gate metal on thermally oxidized Si‐face and a composite layer of Ti‐Au has been used for Ohmic contact on the highly doped C‐face of the substrate. Each structure was diced and bonded on a TO‐8 header with a suitable wire bonding for further testing using in‐house developed LabVIEW‐based computer aided measurement setup.

Findings

The leakage current of fabricated structures shows an asymmetric behavior with the polarity of gate bias ( + V or −V at the anode). A strong relation of oxide thickness and temperature on effective barrier height at SiO₂/4H‐SiC interface as well as on oxide charges have been established and reported in this paper.

Originality/value

The paper focuses on the development of 4H‐SiC based device technology in the fabrication of MOSiC‐based integrated structures.

Citation

Gupta, S.K., Azam, A. and Akhtar, J. (2010), "Experimental analysis of I‐V and C‐V characteristics of Ni/SiO₂/4H‐SiC system with varying oxide thickness", Microelectronics International, Vol. 27 No. 2, pp. 106-112. https://doi.org/10.1108/13565361011034795