1. The two pulses two wavelength driver of EUV radiation LPP source and of 4M Bragg mirror objective for laboratory EUV Lithography tool: Development of the ISTC project #3857 R.Seisyan, A.Zhevlakov, M.Sasin A.F.Ioffe Physical Technical Institute of Russian Academy of Sciences, St.-Petersburg, Russia e-mail: rseis@ffm.ioffe.rurseis@ffm.ioffe.ru

2. ISTC project # 3857 “Key Technologies of EUV-nanolithography System of Super high Resolution on the Base of High Effective LPP Source” February 2009 – February 2012 Project Budget – 317,501 € = $492,700 executors: Ioffe Institute and Institute for Laser Physics, both Saint-Petersburg, Russia

3. Collaborators of the Project 1.Gerry O’Sullivan, 2.John Costello, 3.Torsten Feigl, 4.Peter Choi, 5.Ladislav Pina, all COST MP0601 participants

4. ISTC project #3857, the first year Work Plan 1.Calculation and design of dual-wavelength (λ = 1.06 μm and λ = 10.6 μm) laser- optical scheme forming focal spot on the target at double-pulse illumination. 2.Calculation and design of 4-mirror wide-aperture imaging objective with enlarged image area. 3.Precise mechanical and optical systems development providing for nanometric scale precision for adjustment and focusing of nanolithographer optical system. 4.Placing of the optical and mechanical systems in existing body of NL tool, designed and partly manufactured in the frame of ISTC project #0991.

5. Scheme of EN, designed in the frame of ISTC project #0991 Lens Collector Plasm First Mirror Correction Mirror Mask Second Objective Mirror First Objective Mirror Sample Screen EUV Spectrograph EUV Detector & Filter Coupling system

6. Experimental nanolithographer of Ioffe Institute in the making (2006)

7. View of the experimental hall with the dustless room (center and right) and prototype excimer laser (on the left) used in the Experimental Stand work

8. The main ideas of the industrial EUV LPP source The main ideas used in the SYMER source (as well as in GIGAPHOTON source) are the following. Target material should be Sn (liquid Sn droplets) The main primary laser should be pulsed powerful (about 15-20kW) CO2 laser The main ways to solve debris mitigation problem are the use of magnetic field and The use of inert gas curtain

11. Advanced LPP source for NL tool

12. Cross-section of string source

13. Collector mirror Magnets String target unit The “String” EUV Source cross-section To an objective, samples, etc.. String

14. CapillaryString covered with tin Gas pulse for debris mitigation Ionised Tin, “cold” plasma UV laser pulse 10μ laser pulse: heating Hot, radiating EUV plasma “String” EUV target with different laser wavelength ignition and heating

15. YAG:Nd +3, 1064 nm 1.5 J, 8 ns, 10 Hz Optical delay line, 1-200 ns 2-nd harmonic generator Optical parametrical oscillator H 2 cell CO 2 laser Objective 10  m Objective 1064 nm 532 nm 1930 nm 10  m Former design of dual-wavelength (λ = 1.06 μm and λ = 10.6 μm) laser-optical scheme forming focal spot on the target at double- pulse illumination.

16. Resulting dual-wavelength (λ = 1.06 μm and λ = 10.6 μm) laser- optical scheme forming focal spot on the target at double-pulse illumination

17. Calculation of CO2 laser driver Possible amplification of 6 pass CO2 laser driver (1ns initial pulse)

18. Multipass scheme of CO2 amplifier Multipass scheme for amplifier based on CO2 laser “Fialka” 1 2 L RmRm

19. Experimental Lithographer (EN) made in Ioffe Institute

20. Scheme of EN Lens Collector Plasm First Mirror Correction Mirror Mask Second Objective Mirror First Objective Mirror Sample Screen EUV Spectrograph EUV Detector & Filter Coupling system

21. EN optical scheme Lens Collector Plasm First Mirror Correction Mirror Mask Second Objective Mirror First Objective Mirror Sample Screen EUV Spectrograph EUV Detector & Filter 1233.66 mm 99.9 1256.2 mm Coupling system

22. Bragg mirror imaging systems with high resolution NA=0,06 – 0,09 NA=0,1 – 0,14 NA=0,36 NA=0,485

23. Image modeling L&S 30 nm, contrast 60% L&S 45 nm, contrast 97% L&S 15 nm, contrast 58%

24. Four mirror objective Results of mathematical modeling of microstructures. The image of corners with width of a line 10 nm in the centre of a field

25. The specification of the objective The numerical aperture0.485 The resolution 10 nm with contrast 0.26 20 nm with contrast 0.35 The sizes of the field of the image0.27x0.27 mm 2 → 2.0x2.0mm 2 The central shielding0.407 The distance from a mask up to a plane of the image 829 mm Root mean square wave aberration on the field of the image 0.0573 - 0.1181 The limiting resolution68000 mm with contrast 0.02 The magnification of the objective12

27. 27 Scheme of nanolithograph Lens Collector Plasm First Mirror Correction Mirror Mask Second Objective Mirror First Objective Mirror Sample EUV Spectrograph EUV Detector & Filter Coupling system Third Objective Mirror Fourth Objective Mirror

28. Grating pattern must be such that suppress the second order of diffraction. Principal scheme of focusing and alignment system

30. An original technology for photomask production is developed in the Ioffe Institute for the EN. It includes originally invented mask pattern and construction, and technologies for deposition both reflecting and absorbing structures on the mask surface. The focusing and alignment systems represent by itself multichannel interferometers using gratings and second harmonics solid state laser projection device.

31. Scheme of the focusing system realization

33. Vibroprotective table The EN modules are installed on massive granite plate of vibroprotective table. The table has been invented in the Baltic University (St. Petersburg) and later finished off in conformity with the EN needs. The table has high performance characteristics and provides both passive and active vibroprotection including infralow frequencies.

34. Piezopositioners

35. Phenomenological model of the non-linear photoresist

36. Estimated parameters of inorganic nonlinear photoresists Sensitivity: C = 3×10 -3 cm 3 /J, threshold intensity: I th = 1.7×10 4 W/cm 2, threshold diffusion width: δ = 8.5×10 3 W/cm 2. Dose of H = h/C = 1.7 mJ/cm 2 is sufficient for exposure of a photoresist specimen h=50-nm thick. Pulse threshold dose (at 20 ns) is H th = τI th = 0.34 mJ/cm 2. Thus, the necessary dose is accumulated with 5 pulses at the threshold intensity and 20 ns pulse duration.

37. Computer simulation of the enhancement of the contrast by means of inorganic non-linear photoresist

38. Experiments on the EUV exposure have been carried out with synchrotron 13.4nm emission and, in a tentative form, on the Experimental Stand, the auxiliary setup of the Ioffe Institute, for λ = (13.4 ± 0.3) nm. The results obtained suggest that the EUV sensitivity should be some lower than that at λ = 193 nm. As 2 S 3 films exposed on the synchrotron, after the chemical development, demonstrated distinct interferention structure with 30- 40 nm stripes and space-stripe period about 50-100 nm thereby confirming good resolution ability of the material.

39. QDC (quantum dot crystal) Interference transistor Single-electron transistor QD semiconductor laser Мезоскопические элементы DFB Laser systems Mesoscopic elements Photon crystals