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Strain Balanced AlGaN/GaN/AlGaN nanomembrane HEMTs.

ABSTRACT: Single crystal semiconductor nanomembranes (NM) are important in various applications such as heterogeneous integration and flexible devices. This paper reports the fabrication of AlGaN/GaN NMs and NM high electron mobility transistors (HEMT). Electrochemical etching is used to slice off single-crystalline AlGaN/GaN layers while preserving their microstructural quality. A double heterostructure design with a symmetric strain profile is employed to ensure minimal residual strain in freestanding NMs after release. The mobility of the two-dimensional electron gas (2DEG), formed by the AlGaN/GaN heterostructure, is noticeably superior to previously reported values of many other NMs. AlGaN/GaN nanomembrane HEMTs are fabricated on SiO2 and flexible polymeric substrates. Excellent electrical characteristics, including a high ON/OFF ratio and transconductance, suggest that III-Nitrides nanomembranes are capable of supporting high performance applications.

SUBMITTER: Chang TH

PROVIDER: S-EPMC5527108 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Strain Balanced AlGaN/GaN/AlGaN nanomembrane HEMTs.

Chang Tzu-Hsuan TH Xiong Kanglin K Park Sung Hyun SH Yuan Ge G Ma Zhenqiang Z Han Jung J

Scientific reports 20170725 1

Single crystal semiconductor nanomembranes (NM) are important in various applications such as heterogeneous integration and flexible devices. This paper reports the fabrication of AlGaN/GaN NMs and NM high electron mobility transistors (HEMT). Electrochemical etching is used to slice off single-crystalline AlGaN/GaN layers while preserving their microstructural quality. A double heterostructure design with a symmetric strain profile is employed to ensure minimal residual strain in freestanding N ...[more]

PMID: 28743988

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