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Formation of quantum dots in GaN/AlGaN FETs.

ABSTRACT: GaN and the heterostructures are attractive in condensed matter science and applications for electronic devices. We measure the electron transport in GaN/AlGaN field-effect transistors (FETs) at cryogenic temperature. We observe formation of quantum dots in the conduction channel near the depletion of the 2-dimensional electron gas (2DEG). Multiple quantum dots are formed in the disordered potential induced by impurities in the FET conduction channel. We also measure the gate insulator dependence of the transport properties. These results can be utilized for the development of quantum dot devices utilizing GaN/AlGaN heterostructures and evaluation of the impurities in GaN/AlGaN FET channels.

SUBMITTER: Otsuka T

PROVIDER: S-EPMC7508848 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Formation of quantum dots in GaN/AlGaN FETs.

Otsuka Tomohiro T Abe Takaya T Kitada Takahito T Ito Norikazu N Tanaka Taketoshi T Nakahara Ken K

Scientific reports 20200922 1

GaN and the heterostructures are attractive in condensed matter science and applications for electronic devices. We measure the electron transport in GaN/AlGaN field-effect transistors (FETs) at cryogenic temperature. We observe formation of quantum dots in the conduction channel near the depletion of the 2-dimensional electron gas (2DEG). Multiple quantum dots are formed in the disordered potential induced by impurities in the FET conduction channel. We also measure the gate insulator dependenc ...[more]

PMID: 32963267

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