High integrity SiO2/Al2O3 gate stack for normally-off GaN MOSFET

Hiroshi Kambayashi, Takehiko Nomura, Hirokazu Ueda, Katsushige Harada, Yuichiro Morozumi, Kazuhide Hasebe, Akinobu Teramoto, Shigetoshi Sugawa, Tadahiro Ohmi

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review


High integrity SiO2/Al2O3 gate stack has been demonstrated for GaN metal-oxide-semiconductor (MOS) transistors. The SiO2 film formed on GaN by the microwave-excited plasma enhanced chemical vapor deposition (MW-PECVD) exhibits good properties compared that by the LP (Low Pressure)-CVD. Then, by incorporating the advantages of both of SiO2 with a high insulating and Al2O3 with good interface characteristics, the SiO2/Al2O3 gate stack structure has been employed in GaN MOS devices. The structure shows a low interface state density between gate insulator and GaN, a high breakdown field, and a large charge-to-breakdown by applying 3-nm Al2O3. The SiO2/Al2O3 gate stack has also been applied to AlGaN/GaN hybrid MOS heterojunction field-effect transistor (HFET) and the HFET shows excellent properties with the threshold voltage of 4.2 V and the maximum field-effect mobility of 192 cm2/Vs.

Original languageEnglish
Title of host publicationGate Stack Technology for End-of-Roadmap Devices in Logic, Power and Memory
PublisherMaterials Research Society
Number of pages6
ISBN (Print)9781632661432
Publication statusPublished - 2013
Event2013 MRS Spring Meeting - San Francisco, CA, United States
Duration: 2013 Apr 12013 Apr 5

Publication series

NameMaterials Research Society Symposium Proceedings
ISSN (Print)0272-9172


Conference2013 MRS Spring Meeting
Country/TerritoryUnited States
CitySan Francisco, CA


Dive into the research topics of 'High integrity SiO2/Al2O3 gate stack for normally-off GaN MOSFET'. Together they form a unique fingerprint.

Cite this