We fabricated thin optical layers in aluminum nitride by magnetron sputtering. Using the techniques of integrated optics, we characterized the layers and we determined the electro-optic coefficients of AlN: r13 = 0.67 pm/V and r33 = −0.59 pm/V.

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We give a general introduction into polarized imaging and report on a Jones-pupil approach for a complete evaluation of the resulting optical performance. The Jones pupil assigns a Jones matrix to each point of the exit pupil describing the impact of both the global phase and the polarization on imaging. While we can learn already a lot about the optical system by taking a close look at the Jones pupil -and starting imaging simulations from it -a quantitative assessment is necessary for a complete evaluation of imaging. To do this, we generalize the concept of scalar Zernike aberrations to Jones-Zernike aberrations by expansion of the Jones pupil into vector polynomials. The resulting method is nonparaxial, i.e. the effect of the polarization dependent contrast loss for high numerical apertures is included. The aberrations of the Jones-matrix pupil are a suitable tool to identify the main drivers determining the polarization performance. Furthermore, they enable us to compare the polarized and the unpolarized performance of the such characterized lithographic system.

As the semiconductor industry looks to the future to extend manufacturing beyond 100nm, ASML have developed a new implementation of an old optical method for lithography. Immersion lithography can support the aggressive industry roadmap and offers the ability to manufacture semiconductor devices at a low k1.In order to make immersion lithography a production worthy technology a number of challenges have to be overcome. This paper provides the results of our feasibility study on immersion lithography. We show through experimental and theoretical evaluation that we can overcome the critical concerns related to immersion lithography. We show results from liquid containment tests focussing on its effects on the scan speed of the system and the formation of microbubbles in the fluid. We present fluid-to-resist compatibility tests on resolution, using a custom-built interference setup. Ultimate resolution is tested using a home build 2 beam interference setup. ASML built a prototype full field scanning exposure system based on the dual stage TWINSCAN TM platform. It features a full field 0.75 NA refractive projection lens. We present experimental data on imaging and overlay.keywords: immersion lithography, high NA, TWINSCAN, bath, shower 1.INTRODUCTIONFor more than 25 years the semiconductor industry has predicted the end of optical lithography. Recent developments, however, show us that optical lithography is more alive than ever before. Immersion lithography has emerged as the potential technology for extending optical lithography. Immersion lithography makes use of fluids with refractive indexes that are greater than 1.0 (the refractive index of air) to enable the use of lenses that have Numerical Apertures (NAs) larger than 1.0. Immersion, in principle, is not a new technique. Its viability for microlithography, however, has become a practical consideration because of advances made in lens manufacturing technology, especially a-spherical surface figuring. For 193-nm lithography, water proves to be a suitable immersion fluid. The refractive index for water is 1.43, which makes lens NAs above 1.2 feasible. Immersion offers the potential to extend conventional optical lithography to the 45-nm node and even potentially to the 32-nm node. The main challenges for deployment of immersion are in the design of the exposure tool. Early work done by International Sematech shows that existing photo resists can be compatibility with immersion. However, further work is required in this area.In this paper we discuss the achievements of both exposure tool design and the interaction between existing photoresists and immersion fluids. Section 2 provides the results of our feasibility study on immersion lithography. Section 3 shows the results of our prototype TWINSCAN TM immersion scanner, and finally section 4 summarizes the conclusions of this paper.

The mask plays a significant role as an active optical element in lithography, for both deep ultraviolet (DUV) and extreme ultraviolet (EUV) lithography. Mask-induced and feature-dependent shifts of the best-focus position and other aberration-like effects were reported both for DUV immersion and for EUV lithography. We employ rigorous computation of light diffraction from lithographic masks in combination with aerial image simulation to study the root causes of these effects and their dependencies from mask and optical system parameters. Special emphasis is put on the comparison of transmission masks for DUV lithography and reflective masks for EUV lithography, respectively. Several strategies to compensate the mask-induced phase effects are discussed