| With the fast development of micro-electronic industry in our country, it is keen to research the manufacturing equipment, which is called lithography, for grand scale integration circuits. A type of lithography with 193nm deep ultraviolet exposure wavelength becomes the mainstream equipment for its advantages of mature technology and the critical dimension extends to 32nm. Illumination system, as one of the main parts of lithography, enables to supply high uniformity intensity distribution on the mask, controls exposure dose and creates off-axis illumination (OAI) modes which enhance the resolution and enlarge depth of focus of lithography. The main research contents of this thesis are designing and simulating the main parts of the illumination system for projected lithography at 193nm wavelength.First of all, based on the property of light source and illuminated area, the functions and structures of four key units of illumination system which are beam expanding unit, beam shaping unit, beam homogenizing unit and a relay objective with double telecentric property are analyzed. The total scheme of illumination system is determined and the designing parameters of each unit according to the requirements of lithography are calculated.Secondly, each unit of illumination system mentioned above is designed and simulated. The designing contents are as follows:1. The property of laser beam is analyzed and based on the requirements of beam shape, a multi-mirror components beam expanding unit which can reduce the difficulties of manufacturing and coating is presented. On the other hand, in order to enhance the uniformity of output beam from beam expanding unit, according to the method of sub-beams superimposing, a kind of beam expanding unit with two nonparallel mirrors is presented. This structure makes the uniformity increase to 71.3%.2. Based on the requirements of lithography for the illumination modes, the methods based on geometry optics are used to design an axicon beam shaping unit. Annular and quadrupole illumination modes with the advantages of simple structures and the partial coherent factor can be adjusted continuously at the defined ranges are fulfilled by using this unit. On the other hand, an optimization method based on angular spectrum principle is presented to design a diffraction optical element (DOE) to achieve all kinds of OAI modes from the viewpoint of physics optics. The advantage of the DOE is reducing simulation errors effectively in the near diffraction field. Axicon and DOE are combined to form an optimum beam shaping unit.3. To obtain high uniformity of illumination system, a beam homogenizing unit which consists of tandem lens arrays and telecentric condenser lens is designed.The homogenizing results for different OAI modes are simulated. Results show that the uniformity of traditional illumination, annular illumination and quadrupole illumination are 1.8%, 3.0% and 3.5% respectively.4. In order to achieve pupils matching, reduce errors of magnification and penumbra effect, two kinds of telecentric illumination objectives are designed. The first one uses all-fused-silica material and the telecentric degrees of object and image are 2.2mrad and 2.6mrad respectively. The other one contains four aspheric surfaces and two calcium fluoride lenses to simplify the objective structure. Then the telecentric degree of object and image are 1.5mrad and 1.9mrad respectively. The method of optimizing incident angles is used to reduce tolerance sensitivity.Finally, the whole illumination system is simulated with TIGHTTOOLS. The results show that the uniformities on the mask of traditional illumination, annular illumination and quadrupole illumination are 2.2%, 3.4% and 4% respectively. The telecentric degrees of traditional illumination and OAI on the mask are 2.6mard and 2.8mrad respectively.
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