EXCIMER LASER PULSE ENERGY STABILITY CONTROL METHOD AND SYSTEM

摘要

An excimer laser pulse energy stability control method. Said method comprises: first acquiring an energy measurement value of an nth pulse in a pulse sequence; then calculating the difference between the energy measurement value and an energy set value; taking a zth pulse of the sequence as a demarcation point, and when n is a positive integer less than z, calculating a discharge voltage value of the next pulse according to a first mathematical model, and when n is an integer greater than z-1, calculating a discharge voltage value of the next pulse according to a second mathematical model; and finally, generating a next pulse according to the calculated discharge voltage value. The control method can effectively control the energy overshoot in each pulse sequence and the stability of energy of all pulses in one pulse sequence. A control system based on the control method comprises: a high-voltage discharge module (1), a laser cavity (2), a laser parameter measurement module (3) and an energy stabilization controller (9). The system has a simple structure, and the energy stability control over the system can be realized only by separating a small amount of energy.