Excimer laser pulse energy detecting under pulse repetition running mode

Abstract

Abstract:

An Excimer Laser pulse energy detecting system was introduced, which is able to pick out either a single pulse energy or the individual energy of a desired series of pulses during the laser runs in a pulse repetition mode up to 200Hz. By use of a pyroelectric detector as energy sensor the system consists of amplifiers, peak-holding circuits, MCU, display and communication interface. Owing to an excellent interference suppressor circuit design the system run well even if the thyratron discharging EMI is very strong. Tested on the 193nm ArF and 248nm KrF Excimer laser the system behaved as follows: response time-4ms, power resolution-10 , sensitivity-0.5 and power accuracy- 3％. This system could be used as an energy-meter alone or be as a real time detector in a closed feedback loop for laser pulse energy stabilization. After substituting the pyroelectric detector with a photomultiplier tube it is expected that the system would be suitable for repetition rate higher than 1kHz.

Key words: laser techniques｜excimer｜pyroelectric｜feedback｜real time

LIANG Xu , YOU Li-bing , YU Yin-shan. Excimer laser pulse energy detecting under pulse repetition running mode[J]. J4, 2010, 27(3): 281-287.

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