A device configured to convert or amplify a particle, the conversion or amplification being reliant on the impact of a particle on a surface of the device causing emission of one or more secondary electrons from the same surface. The device includes a carbon-based layer capable of secondary electron emission upon impact of a particle. The surface may be used to convert, for example, an ion into an electron signal, or an electron signal into an amplified electron signal, such as in conversion or amplification dynodes.

An electron multiplier includes an insulating substrate which includes an electrical wiring pattern and in which a through-hole is formed, an MCP arranged on one side of the through-hole of the insulating substrate and electrically connected to the electrical wiring pattern, a shield plate arranged in one side of the MCP and electrically connected to the MCP, an anode arranged on the other side of the through-hole and electrically connected to the electrical wiring pattern, and a signal readout terminal fixed to the insulating substrate for reading a signal from the anode. The shield plate is formed to include the MCP when viewed in a thickness direction. A through-hole exposing at least a portion of the MCP is formed in the shield plate. The insulating substrate, the MCP, the shield plate and the anode are fixed to each other to be integral.

A high power RF energy device component is disclosed that is exposed to high power RF energy in a vacuum environment, and includes a multipactor-inhibiting carbon nanofilm covering at least one surface of the component. A secondary electron efficiency emission (SEE) coefficient of the multipactor inhibiting carbon nanofilm is desirably less than a SEE coefficient of the underlying surface of the component.

A high power RF energy device component is disclosed that is exposed to high power RF energy in a vacuum environment, and includes a multipactor-inhibiting carbon nanofilm covering at least one surface of the component. A secondary electron efficiency emission (SEE) coefficient of the multipactor inhibiting carbon nanofilm is desirably less than a SEE coefficient of the underlying surface of the component.