Motion Control for wafer stage of 0.1μm lithography

Abstract

In this paper, a particular mechanical servo system is presented based on the design requirement of scanning wafer stage of 0.1μm lithography. In order to achieve high accuracy and high speed, linear motor and voice coil motor is employed to control long stroke motions and short stroke motions, respectively. Considering extraneous forces resident in the system, a composite movement model with disturbing compensation employing an open-closed-loop D-type Iterative Learning Controller(ILC) is then given. The results of actual application demonstrate that the given system with better robustness can enhance the real-time tracing ability and can satisfy high accuracy at high speed along specified trajectories.

Delay-based Design of Feedforward Tracking Control for Predictable Embedded Platforms

“…, D c can be increased either by adding partition slots between control tasks or by adding a delay in execution of actuation in its partition slot 2 . In this case D c can be defined as:…”

“…Here, we use Zero-Phase-Error Tracking controller (ZPETC) stable approximation [18]. To design ZPETC, we first rewrite G CL as: 2 The execution of sensing and computation always starts at the beginning of their respective slots.…”

“…High precision motion control systems play an important role in many domains like robotics [1], lithography [2], and many more [3]. They perform fast and accurate tracking of a predefined reference signal [1], e.g., motion path.…”