Nb$_{2}$O$_{5}$ high-k dielectric enabled electric field engineering of $β$-Ga$_{2}$O$_{3}$ metal-insulator-semiconductor (MIS) diode

Prabhans Tiwari; Jayeeta Biswas; Chandan Joishi; Saurabh Lodha

doi:10.1063/5.0075627

paper

Nb $_{2}$ O $_{5}$ high-k dielectric enabled electric field engineering of $β$ -Ga $_{2}$ O $_{3}$ metal-insulator-semiconductor (MIS) diode

arXiv:2110.13129 · doi:10.1063/5.0075627

Abstract

We demonstrate an Nb $_{2}$ O $_{5}$ / $β$ -Ga $_{2}$ O $_{3}$ metal-insulator-semiconductor (MIS) hetero-junction diode with Nb $_{2}$ O $_{5}$ as the high-k dielectric insulator for more efficient electric field management resulting in enhanced breakdown characteristics compared to a $β$ -Ga $_{2}$ O $_{3}$ Schottky barrier diode. The Nb $_{2}$ O $_{5}$ dielectric films were grown using atomic layer deposition and exhibited a high dielectric constant of 50. The high dielectric constant resulted in a 5 $\times$ lower electric field at the metal/dielectric interface in the MIS diode compared to the metal/ $β$ -Ga $_{2}$ O $_{3}$ interface in the Schottky barrier diode. With good electron conduction in forward bias enabled by the negative conduction band offset of Nb $_{2}$ O $_{5}$ w.r.t $β$ -Ga $_{2}$ O $_{3}$ , the MIS design led to a 3 $\times$ improvement in the reverse blocking voltage with a slight trade-off in the specific on-resistance. Overall, a 3.3 $\times$ increase in the power figure of merit was observed (3.25 MW/cm $^{2}$ for the Schottky diode and 10.8 MW/cm $^{2}$ for the MIS diode). A detailed analysis of the energy band line-up, and the forward and reverse current transport mechanisms are also presented using analytical modeling and 2-D TCAD simulations.

The following article has been submitted to 'Journal of Applied Physics' and the link will be updated if it gets published

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Electric field management in $β$ - $G a_{2} O_{3}$ vertical Schottky diodes using high-k bismuth zinc niobium oxide

Nb2​O5​ high-k dielectric enabled electric field engineering of β-Ga2​O3​ metal-insulator-semiconductor (MIS) diode

Abstract

References in corpus (3)

Cited by in corpus (1)

Nb $_{2}$ O $_{5}$ high-k dielectric enabled electric field engineering of $β$ -Ga $_{2}$ O $_{3}$ metal-insulator-semiconductor (MIS) diode