| The wavelength of extreme ultraviolet (EUV) radiation is so short that it overlaps with soft X-ray spectral band. Within the overlap band, due to its coherence effect, the radiation with the same wavelength is sometimes called as EUV light, but at some occasion as soft X-ray laser, which maybe owing to people's oral habit. Whatever name it is, the short wavelength source comes mainly from emission of high-temperature and high-density plasma. It is the capillary discharge setup which produces higher conversion efficiency of energy that directly transforms electric power to plasma emission energy.A great deal of pumped energy has to be used in obtaining soft X-ray laser emission with short wavelength. It is almost impossible to build resonance chamber for soft X-ray laser because of intense reabsorption by materials. These adverse factors have restricted the development of soft X-ray laser for a long time, especially those lasers with advantages such as small-size, tabletop, high-efficiency, cost-effective and practicability. However, Establishment and successful operation of capillary discharge soft X-ray laser device smashed the developmental durance, which could hopefully realize truly-applied and small-sized and high-efficient soft X-ray laser. In this dissertation, based on the introduction of elemental theory of X-ray laser, the experimental work concerning extensive research on the basis of prophase working uses the capillary discharge soft X-ray laser equipment at our laboratory. The experiment includes studying effect of time delay of mainpulse current on laser output, probing the mainpulse current threshold with lasing at low Ar pressure and identifying 46.9nm laser spectrum. It is discovered from experimental data that there exists a good time delay range corresponding to lasing in which includes an optimal range corresponding to larger lasing. In the meantime, The experimental result also illustrates the relationship between the time delay and Ar pressure, finds out the mainpulse current threshold of ~19kA with lasing at Ar pressure of 28~46Pa and identifies the 46.9nm laser spectrum in capillary discharge. By modifying the main-switch support, impact of the main-switch inductance on lasing is investigated. After its modification, the main-switch inductance decreases by 15%, the average mainpulse current increases by 4%, the average laser output improves by 31%, and at the same time it inherits the high-voltage endurance and lasing stability before modification. As a supplement, the dissertation provides the design plan for measurement and detection shifting chamber in capillary discharge which will not only survey laser energy and spectrum, but possibly improve experimental precision greatly as well.Extreme ultraviolet lithography (EUVL) technology is one of the popular researches at present, which reduces the circuit pattern in the mask onto photoresist layer by using very short wavelength EUV light. It can obtain resolution width below 30nm by no help of resolution factor enhancement technology, which will be the possible candidate for replacing ArF immersion lithography and become the mainstream of next generation lithography technology. It is the capillary discharge EUV source that exhibits higher output power and conversion efficiency of energy. In this paper, some qualitative calculation of the important parameters and operating condition of capillary discharge EUV source are made in order to provide references to its establishment. After that, the author participates in the work of designing, installation, debugging and checking of the setup and later engages experimental research for EUV emission with gas medium. By discharging to real load, it is discovered that the voltage and current of prepulse source attain ~7kV and 40~60A respectively, and those of mainpulse source attain ~30kV and 20~40kA respectively. Furthermore, both of them can work at one time or at repetition rate of 1~200Hz, which manifests that all kinds of discharge parameters conform to the designing standard. When the setup is completed, the EUV spectrum in capillary discharge by calibrated Rowland circle spectrometer is studied, and the EUV emission of Ar7+ and He+ ions around 30nm are found from experimental result. The experimental data confirms that the plasma emission spectrum lies in the EUV objective zone and the built-up capillary discharge EUV demonstrative setup works safely and stably which can be used to perform the next experiment with EUV output.There are many research groups and organizations of the world working on EUVL source research. With development of investigation, the output power of EUV source increases gradually, and have attained the standard for application. However, the high power source depends mostly on very high repetition rate while the single output energy is not big enough. Still more, the extremely high frequency of operation makes lithographic process difficult and environment rigid which gives rise to cost of ownership. In this dissertation, the design scheme of capillary discharge three-plasma EUV loop source is brought forward so as to solve the problem of the singly less output power of lithographic source. By analysis of force in the process of loop source formation of three-plasma in capillary discharge, the output parameters, comparatively comprehensive design and demonstration, are calculated qualitatively. The result demonstrates that, under the same total current condition, the emission volumn of three-plasma loop source increases as ~10 times big as normal capillary, and the optimal collection angle of it enlarges by ~60% and conversion efficiency of power enhances ~5 times. These qualitative result indicate that capillary discharge three-plasma loop source exhibits great investigative potential but the basic research needs to be continue.The dissertation pays equal attention to the theory, setup and experiment. It is known from the paper that more detail experimental study are carried out with the lasing capillary discharge soft X-ray laser equipment, the first new capillary discharge EUVL source demonstrative setup is made, and the design scheme of capillary discharge three-plasma high-power (single operation) EUV loop source is put forward. These productions set a solid base on thorough research of capillary discharge EUV source in the future.
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