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Influence of the ratio of gate length to drain-to-source distance on the electron mobility in AlGaN/AlN/GaN heterostructure field-effect transistors.

ABSTRACT: Using measured capacitance-voltage curves with different gate lengths and current-voltage characteristics at low drain-to-source voltage for the AlGaN/AlN/GaN heterostructure field-effect transistors (HFETs) of different drain-to-source distances, we found that the dominant scattering mechanism in AlGaN/AlN/GaN HFETs is determined by the ratio of gate length to drain-to-source distance. For devices with small ratio (here, less than 1/2), polarization Coulomb field scattering dominates electron mobility. However, for devices with large ratio (here, more than 1/2), longitudinal optical (LO) phonon scattering and interface roughness scattering are dominant. The reason is closely related to polarization Coulomb field scattering.

SUBMITTER: Lv Y

PROVIDER: S-EPMC3477020 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature

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Influence of the ratio of gate length to drain-to-source distance on the electron mobility in AlGaN/AlN/GaN heterostructure field-effect transistors.

Lv Yuanjie Y Lin Zhaojun Z Meng Lingguo L Luan Chongbiao C Cao Zhifang Z Yu Yingxia Y Feng Zhihong Z Wang Zhanguo Z

Nanoscale research letters 20120803 1

Using measured capacitance-voltage curves with different gate lengths and current-voltage characteristics at low drain-to-source voltage for the AlGaN/AlN/GaN heterostructure field-effect transistors (HFETs) of different drain-to-source distances, we found that the dominant scattering mechanism in AlGaN/AlN/GaN HFETs is determined by the ratio of gate length to drain-to-source distance. For devices with small ratio (here, less than 1/2), polarization Coulomb field scattering dominates electron m ...[more]

PMID: 22856465

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