1. Ultra-precision engineering in lithographic exposure equipment for the semiconductor industry by Robert-H. Munnig Schmidt Philosophical Transactions A Volume 370(1973):3950-3972 August 28, 2012 ©2012 by The Royal Society

2. Integrated circuit production flow, starting with a mono-crystalline silicon ingot, cut into thin slices (wafers) that undergo a multitude of chemical treatments, where all dimensions are determined by the optical exposure system at step 5. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

3. The smallest details (CD) that can be imaged by a wafer scanner are determined by the numerical aperture (NA) of the imaging system. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

4. State-of-the-art wafer scanner from ASML indicating the main functional modules for exposing a wafer. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

5. The scanning principle of a wafer scanner. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

6. The requirements on overlay follow a trend that outpaces Moore’s Law. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

7. Several measures are taken to avoid dynamic problems in modern wafer scanners. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

8. Active ‘skyhook’ damping in a vibration isolation system avoids the transmission of external vibrations through the damper. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

9. Electromagnetic Lorentz type actuator. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

10. A long-stoke, short-stroke positioning stage in an H-configuration, where the actuator forces all act in the plane of the centre of mass of the wafer table. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

11. The forces acting on a coil, positioned in the magnetic field above an array of alternating permanent magnets. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

12. The alignment marks are diffraction gratings with a different periodicity to increase the capture range. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

13. The required depth of focus as a function of the critical dimension. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

14. The process steps in a dual stage wafer scanner between loading and unloading consist of two cycles. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

15. By curving the image plane, the image can be made to better conform to the local curvature of the wafer. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

16. Two methods for long-range incremental position measurement. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

17. The combination of (a) the H-configuration with the laser interferometer measurement system and (b) the plane encoder with the planar actuation system clearly illustrate the differences. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

18. The position control of the wafer stage is a SISO six-axis PID-control system. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society

19. Cross section of a CMOS logic microprocessor IC of IBM, showing 20 nm width vacuum chambers as insulator for reduced dielectric losses, created by a ‘self assembly’ process. Robert-H. Munnig Schmidt Phil. Trans. R. Soc. A 2012;370:3950-3972 ©2012 by The Royal Society