OVERVIEW OPERATING PRINCIPLE OVERVIEW OPERATING PRINCIPLE

MCP (microchannel plate) is a two-dimensional sensor that detects electrons, ions, vacuum UV rays, X-rays and gamma rays, and amplifies the detected signals. Circular and rectangular MCPs are available in various dimensions, including easy-to-use MCP as-semblies with pre-mounted industrial electrode leads and supports. These MCPs are widely used in many types of analytical equipment such as for "mass spectroscopy", "semiconductor inspection" and "surface analysis".The MCP assemblies are available with three different readout devices to meet application needs. The devices are of: (1) single anode (electrical output signal measurement within effective region), (2) multianode (electrical output signal measurement corre-sponding to signal input positions), and (3) phosphor screen (optical imaging of output signal). Select the output device that best matches your application. From one to three stage MCPs can be selected for the assembly to obtain necessary gain, allowing uses in the analog mode (the output signal is measured as a continuous electrical current) or the counting mode (the low level signal can be measured by a binary processing). As shown in the figure on the right, a potential gradient is estab-lished along the channel when the voltage V

D

is applied between the input and output sides of the MCP. Multiple secondary elec-trons are emitted when an electron enters a channel from the in- put side and strikes its inner wall. These secondary electrons are accelerated by the potential gradient to draw parabolic trajecto- ries that are determined by their initial velocities. They then strike the opposite wall in the channel causing further secondary elec-trons to be emitted. The electrons in this way travel towards the output end while striking the inner wall of the channel repeatedly. As a result, a large number of exponentially increased electrons are extracted from the output side.

Schematic Structure of MCP

CHANNELS CHANNEL WALLSTRIPCURRENTONE INTPUT ELECTRONOUTPUT ELECTRONS OUTPUT SIDE ELECTRODE INPUT SIDEELECTRODE
VD TMCPC0002EE

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