Single particle detector system for high resolution time measurements

A compact detector system for single particles (e.g., for time-of-flight mass spectrometry) with an input area 27 mm in diameter and an overall height of 20 mm has been developed using a two-stage chevron micro channel plate (MCP) and a high-speed trigger circuit. A special anode configuration with a thick-film ceramic provides up to 7 kV insulation between the anode of the MCP and the following electronics as well as wide bandwidth without ringing. Additionally, the mean position information of the particles is available by dividing the anode into 16 segments. The average current for each segment is monitored. The high-speed trigger circuit is directly mounted into the detector system. The MCP response with its wide amplitude variation is converted into an emitter coupled logic level signal. The power dissipation is less than 300 mW. A time resolution of 500 ps and a dead time of less than 3 ns are achieved.<>