We designed a system to produce atmospheric hybrid cold-discharge plasma (HCP) based on microcorona discharge on a single dielectric barrier and applied it to inactivate microorganisms that commonly attach the rice seed husk. The cold-plasma treatment modified the surface of the rice seeds, resulting in accelerated germination and enhanced water imbibition. The treatment can operate under air-based ambient conditions without the need for a vacuum. The cold-plasma treatment completely inactivated pathogenic fungi and other microorganisms, enhancing the germination percentage and seedling quality. The final germination percentage of the treated rice seeds was ∼98%, whereas that of the nontreated seeds was ∼90%. Microcorona discharge on a single dielectric barrier provides a nonaggressive cold plasma that can be applied to organic materials without causing thermal and electrical damage. The hybrid nonthermal plasma is cost effective and consumes relatively little power, making it suitable for the surface sterilization and disinfection of organic and biological materials with large-scale compatibility.

This paper presents a new gate drive circuit for driving a series string of IGBTs. The proposed quasi active gate control (QAGC) circuit is simple to implement as it composes of only a few passive components in addition to a standard gate driver. No separate isolation power supply is required for the upper devices in the stack. The proposed QAGC circuit provides an effective way to drive the power devices and control static and dynamic voltage sharing to the devices at the same time. The theoretical switching operation and the oscillation stability analysis allow criteria for component selection to be established. Limitations of the QAGC circuit is also identified. The modification of the circuit to support more power devices in the series stack is discussed with the aid of the simulation results. The switching operation of the circuit is validated from the experimental results using 2 IGBTs connected in series. The circuit shows a satisfied switching operation with well-controlled dynamic and static voltage sharing and comparable gate voltage between the coupled devices.

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1 Introduction Carrier multiplication (CM) is an interesting principle for intensifying the solar energy conversion efficiency by converting a single photon into multiple electrons. However, it is known that multiple exciton generation (MEG) is more efficient in a quantum confined system such as a quantum dot, nanocrystals and 2-dimensional based structures rather than bulk silicon [1][2][3][4]. Due to the unique and remarkable 2D physical properties, such as a high transparency to light and exceptional carrier mobility, graphene has received considerable attention for future nanoelectronic and photonic applications [1][2][3][4][5][6][7], and graphene also demonstrates the MEG process [9,10]. Nonetheless, a graphene-based photodetector itself exhibits low quantum efficiency due to its low optical absorption and picosecond recombination time [6,8]. On the other hand, the silicon-based devices have a long lifetime (on