By: Udayasri Jandhyala Kanchan Joshi

1. By: • Udayasri Jandhyala • Kanchan Joshi ME250 Prof. Furman

2. By: • Udayasri Jandhyala • Kanchan Joshi ME250 Prof. Furman

3. Lithography: A basic photographic process that allows more features to be crammed onto a computer chip. • EUVL: Lithography at extreme UV wavelengths is called EUVL. • Lithography Process: Light is directed onto a mask-a sort of stencil of an integrated circuit pattern and the image of that pattern is then projected onto a semiconductor wafer covered with light sensitive photoresist. • Present: Current lithography techniques use deep ultraviolet range 248nm wavelengths to print 150 to 120nm size features. • Future is EUVL: Creating smaller features requires wavelengths in the Extreme Ultraviolet range. Light at Extreme Ultraviolet wavelengths is absorbed instead of transmitted by lenses. • Industry Developments: LLNL has developed multilayer coatings capable of reflecting nearly 70% of EUV light at a wavelength of 13.4nm that can be used to fabricate structures with a smaller minimum feature size 50nm. ME250 Prof. Furman

4. ME250 Prof. Furman

5. Micro Exposure tool (MET): • A two-mirror camera which is capable of printing 30nm features. • Functional Requirements: • Low distortion support of the optics • Precision adjustments for aligning the optics • Dimensional stability,both long term-alignment and short term-image placement ME250 Prof. Furman

6. The support ring provides upper and lower kinematic mounting interfaces available to MET. • The support ring has a 360 degrees rotational interface to the M2 cell for the clocking adjustment and it provides attachment points for six actuation flexures. • The triangular shaped M1 cell attaches to the opposite ends of the actuation flexures and together they provide high resolution adjustment in 5 dof critical for optical alignment. • Why Flexures: • Strain attentuation • The function of actuation flexure is to provide a single,adjustable constraint along its axis. It is remotely actuated during alignment process but otherwise functions as a passive constraint. • The M1 and M2 cells each support three flexures that combine to constrain 6dof for each optic. • The support ring, actuation flexures etc are manufactured from Super Invar (a low CTE alloy). ME250 Prof. Furman

7. Actuation System: The actuation flexures support and move the M1 cell relative to the support ring (often called a Stewart platform). • All six members are required to provide rigid constraint and any pure motion of the stage requires coordinated motion of all six flexures. • A number of factors are considered and balanced in the design of actuation flexure. • It must provide stiff axial constraint, sufficient compliance and range of motion in the non constraint directions, low actuation force. ME250 Prof. Furman

8. Projection Optic Mount: Objective: Kinematic Constraint Optic Cell Bipod Flexure Optic ME250 Prof. Furman

9. 3DOF Blade Flexure: l z x w y Blade thk=t l=10*t w=l ME250 Prof. Furman

10. 4DOF Bipod Flexure: • Features: • Blades in series to add compliances • Equivalent to a sphere and a vee • Connect-disconnect function • Repeatable forces on optic z x y ME250 Prof. Furman

11. The final assembly: • Mechanical assembly • Precision • Accuracy ME250 Prof. Furman