Abstract
An unexplored type of vertical graphene heterostructure FET (VGHFET) with an ultrathin ferroelectric film as a tunnel barrier has been developed. This is fundamentally different from existing planar graphene?ferroelectric FETs. With the unique ferroelectric switching resulting in large amplification of tunneling current, we have demonstrated a room-temperature current on/off ratio of 7 x 107, the highest ever reported for all types of graphene-based field-effect transistor (GFETs). The intensity is observed to be approximately twice as high for the 2D peak at 2700 cm-1as for the G peak at 1580 cm-1. The full width half-maximum of 2D peak is less than 30 cm-1. A D defect peak was seen from the graphene after depositing BFO, probably arising as a result of the highly energetic growth process of the pulsed laser deposition (PLD). The Raman spectra indicate that the graphene is still monolayer after BFO deposition. In order to ensure that the quality of graphene is maintained after BFO deposition, the mobility of the graphene after the BFO deposition was measured, and was found to be only slightly decreased compared to that of the graphene before growing the BFO. The results suggest that the graphene after BFO deposition can satisfy the needs of further device applications in this work.
Original language | English |
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Pages (from-to) | 10048-10054 |
Number of pages | 7 |
Journal | Advanced Materials |
Volume | 28 |
Issue number | 45 |
DOIs | |
Publication status | Published - 1 Jan 2016 |
Keywords
- 2D materials
- ferroelectric thin films
- field-effect transistors
- graphene
- pulsed laser deposition
ASJC Scopus subject areas
- General Materials Science
- Mechanics of Materials
- Mechanical Engineering