Hiroshi Mizuta

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The direct growth of graphene on insulating substrate is highly desirable for the commercial scale integration of graphene due to the potential lower cost and better process control. We report a simple, direct deposition of nanocrystalline graphene (NCG) on insulating substrates via catalyst-free plasma-enhanced chemical vapor deposition at relatively low(More)
The impact of dopant atoms in transistor functionality has significantly changed over the past few decades. In downscaled transistors, discrete dopants with uncontrolled positions and number induce fluctuations in device operation. On the other hand, by gaining access to tunneling through individual dopants, a new type of devices is developed:(More)
Dynamic random access memories (DRAMs) based on a transistor/capacitor cell are used as main memories in computers because of their high capacity and high speed. Since there is no gain in the present DRAM cell, it requires a large cell-capacitor to produce an adequate sense signal. In each new memory generation, structure and fabrication have become more(More)
We investigate the impact of varying the grain boundary (GB) position on the output (I d –V d) characteristics of submicron single GB polysilicon thin film transistors (TFTs), by two-dimensional (2D), drift-diffusion based, device simulation. We employ a localized GB trapping model with a distribution of both donor-like and acceptor-like trap states over(More)
A simulation model for deep trap states at grain boundaries in Poly-Si TFTs is developed. The model is used for simulation of single GB TFT devices with sub micron channel lengths. The transport physics is clarified and it is found that in short channel devices (L/sub eff/<100 nm) the single GB TFT shows improved subthreshold behaviour compared to its SOI(More)
Resistive random access memories (ReRAMs) are promising next-generation memory devices. Observation of the conductive filaments formed in ReRAMs is essential in understanding their operating mechanisms and their expected ultimate performance. Finding the position of the conductive filament is the key process in the preparation of samples for cross-sectional(More)
This paper reports on large area, metal-free deposition of nanocrystalline gra-phene (NCG) directly onto wet thermally oxidized 150 mm silicon substrates using parallel-plate plasma-enhanced chemical vapor deposition. Thickness non-uniformities as low as 13% are achieved over the whole substrate. The cluster size L a of the as-obtained films is determined(More)