Injection-locking Of Pulsed Gas Lasers And Design Of The Ring Cavity For Power Oscillator

The development of lithography technology has attracted great attention as a key driverof the semiconductor industry. Injection-locking which is a key technology to obtain highperformance light source for lithography was studied in this dissertation.First of all, the concept of injection locking was discussed. On this basis, line widthcompression module, power oscillator resonator module, isolation devices and delay controlmodule were described, analyzed and compared. Secondly, TEA CO2lasers were used toinvestigate the pulsed signal injection locking. The factors which affect the performance ofinjection locking, such as the delay of seed, the branch of seed, the power of seed and thematch of transverse mode were all studies. Then the best delay time of seed was obtained,and the maximum output power can be gotten at the best delay time, and apart from the bestdelay, the output power decreased. And with the growing of seed energy, the amplifyingmagnification decreased to saturation point slowly, and the saturation magnification is about3. Meanwhile, the injection-locking becomes more difficult with a injected laser line withlow gain in power oscillator when it was working in multiple branches. In addition,transverse mode matching plays an important role in injection-locking. The experimentalcomparison between MOPA (master oscillator power amplification) and MOPO (masteroscillator power oscillator) was made, it was found that the amplifying magnification ofMOPA maintained at1.8times and has nothing to do with seed energy, and output power ofMOPA was much smaller than that of MOPO. At last, several ring cavities of poweroscillator were designed. Based on the structure of an excimer laser’s discharge cavity, thethree-mirror ring cavity, the prism ring cavity, an improved prism ring cavity and four-mirrorring cavity were analyzed, which were prepared for the subsequent experiments of injectionlocking of excimer laser. These results will be helpful for the study of injection-lockedamplification method of excimer laser.