Work

Weak Frequency Dispersion of C–V Characteristics of AlGaN/GaN Metal‐Insulator‐Semiconductor Devices Despite High Interface Trap Density

Year: 2025

Type: article

Abstract: For AlGaN/GaN metal‐insulator‐semiconductor (MIS) devices, it is shown that there is a case where the frequency dispersion of the capacitance–voltage (C–V) characteristics is very weak despite a rather high insulator–semiconductor interface trap density. We fabricated metal/Al2O3/AlGaN/GaN MIS devices, and carried out C–V characterization of them. Although they exhibit very weak C–V frequency dispersion for 100 Hz–1 MHz, we found that, based on the conductance method, the insulator–semiconductor interface trap densities are rather high ≈3 × 1013 cm−2 eV−1. As a possible explanation, a double‐peak model is considered, which underlines the possibility that a high interface trap density does not necessarily lead to strong C–V frequency dispersion. The model can explain the observed weak C–V frequency dispersion, implying that it is not appropriate to naively discuss the interface traps only from the apparent C–V frequency dispersion.

Source: physica status solidi (a)

DOI: 10.1002/pssa.202500266

Authors: Yuchen Deng, Jieensi Gelan, Kazuya Uryu, Toshi‐kazu Suzuki

Institutions: Japan Advanced Institute of Science and Technology, Advantest (Japan)

Language: English

Topic: GaN-based semiconductor devices and materials

Subfield: Condensed Matter Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: bronze

Funder: Japan Society for the Promotion of Science

Awards: G3776550416, Threshold voltage control of nitride semiconductor devices by combining interface-charge and strain-polarization engineering