Single photon detection on atomically thin film by control of electrode interface

2017 Fiscal Year Final Research Report

• Project/Area Number: 16K14259
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Electron device/Electronic equipment
• Research Institution: Osaka Prefecture University
• Principal Investigator: Seiji Akita 大阪府立大学, 工学(系)研究科(研究院), 教授 (60202529)
• Co-Investigator(Renkei-kenkyūsha): ARIE Takayuki 大阪府立大学, 工学研究科, 准教授 (80533017)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Keywords: 原子層膜 / グラフェン / 硫化モリブデン / 光センサ / 界面トラップ

Outline of Final Research Achievements

This study investigates not only the steady state but also the transient photoresponse of graphene field-effect transistor (G-FET) of which gate bias is applied through the Schottky barrier formed at an n-type Si/graphene interface with a thin oxide layer. We revealed that the tunneling process through the SiOx layer to graphene occurs along with recombination of the accumulated holes and the electrons in the graphene at the surface states on the SiOx layer.The photosensitivity is improved about 2 orders of magnitude, which resulted in a single photon detection. In addition, we investigate the photoresponse of a MoS2 FET with a thin Al2O3 buffer layer at the interface on a gate insulator. The application of a 2-nm-thick Al2O3 buffer layer at the interface greatly improves not only the photosensitivity (5 orders of magnitude high sensitivity) but also the response speed (10,000 times faster).

Free Research Field

ナノデバイス