High-performance beam stabilization for next-generation ArF scanner systems

Abstract

With the advent of 193 nm systems processing 300 mm wafers, the production lithography cell is about to undergo a technology shift. The mechanism for delivering the beam from the light source to the illumination system, here referred to as a Beam Delivery Unit (BDU), must change to meet the challenges imposed by this shift. To support these changes, Cymer is developing a BDU that will guarantee a stable beam at the scanner entrance during exposure. The beam stabilization control system has been implemented in a test BDU. We shall present results from experiments that demonstrate our ability to significantly improve short and long term "Beam Stability".

Improving laser cutting quality of carbon fiber-reinforced plastics by improving laser beam pointing stability

“…For this problem, the average deviation correction method was proposed. 44 The average deviation correction method is based on the assumption that, when the pulsed laser repeats at a high frequency, the deviations between laser pulses are not completely isolated but follow a pattern. In addition, the pulses can be divided into pulse segments (consisting of multiple adjacent pulses) that contain the same number of pulses, and larger offsets only occur between pulse segments.…”

“…Additionally, the measurement dates of the previous pulse laser can only be used as a criterion for the subsequent pulse adjustment, which is more random and cannot be used to precisely adjust the subsequent pulse by the previous pulse. For this problem, the average deviation correction method was proposed 44 …”

Decoupling of the position and angular errors in laser pointing with a neural network method

“…In this case, however, the position error of the laser is totally sacrificed. For applications requiring both the position and angular errors, such as fine optical systems [ 8 ] , laser resonator alignment [ 9 ] , laser beam drift control [ 10 ] and lithography [ 11 , 12 ] , the common decoupling method for these two errors involves making two measurements, with one measurement on the in-focus plane and the other on the out-of-focus plane. It can be implemented by repositioning detectors at different locations [ 9 ] , or splitting the beam into two paths [ 10 – 14 ] .…”