Abstract
In this study, we had been proved the application of chemical shrink technique in the electron shaped beam lithography is practicable. The chemical shrink reaction is catalyzed by the photoacid in the resist. During the mixing bake step, the cross-linker undergoes crosslinked reaction with the polymer in shrink agent. The new crosslinked material forms aside the sidewall of the resist pattern. The baking temperature and baking time of the shrink process control the shrink ratio. In a well-controlled situation, the shrink ratio could reach 60% as well as the shrinkage is 60 nm. It could enhance the shrink ratio by omitting the soft bake step of the shrink process, moreover, it's won't cause any influence to the stability of the shrink process. According the critical dimension reducing, the tolerance of the pattern width variation is also contraction. The time between the exposure step and post exposure bake is called the atmospheric delay effect (ADE). It cause serious problem to the resist pattern. When the atmospheric delay is over 30 min, it will make the dimension shifting out of the process window. The main reason, which causes the atmospheric delay effect, is the resist pattern is polluted by the airborne molecular contamination (AMC). In this study, it is effective to identify the individual molecular of these contaminations by using the gas chromatographic mass spectrometer (GC-MS). These data could help the process engineer to prevent the contamination. If the photoresist contains the metal impurity, these impurities will migrate into the device during the photolithographic process, and cause the electric property degrading. For this reason, it is important to insurance the quality of the photoresist. At Present, the microwave-assisted digestion is the most common pre-treatment method to sample analysis. There is several parameters will influence the microwave-assisted digestion ratio, including: digestion temperature, digesting solution type, sample type, volume of digesting solution, digestion holding time and sample weight. In this study, we had investigated the influence of the digestion ratio to these factors. The digestion temperature and the digesting solution type are the most important factor to the digestion ratio.