Dynamic absorption coefficients of chemically amplified resists and nonchemically amplified resists at extreme ultraviolet

作者：Fallica Roberto^*; Stowers Jason K; Grenville Andrew; Frommhold Andreas; Robinson Alex P G; Ekinci Yasin

来源：Journal of Micro/ Nanolithography, Mems, and Moems, 2016, 15(3): 033506.

DOI：10.1117/1.JMM.15.3.033506

• absorption coefficient
• Dill parameters
• chemical sensitivity
• clearing volume
• clearing radius

The dynamic absorption coefficients of several chemically amplified resists (CAR) and non-CAR extreme ultraviolet (EUV) photoresists are measured experimentally using a specifically developed setup in transmission mode at the x-ray interference lithography beamline of the Swiss Light Source. The absorption coefficient a and the Dill parameters ABC were measured with unprecedented accuracy. In general, the a of resists match very closely with the theoretical value calculated from elemental densities and absorption coefficients, whereas exceptions are observed. In addition, through the direct measurements of the absorption coefficients and dose-to-clear values, we introduce a new figure of merit called chemical sensitivity to account for all the postabsorption chemical reaction ongoing in the resist, which also predicts a quantitative clearing volume and clearing radius, due to the photon absorption in the resist. These parameters may help provide deeper insight into the underlying mechanisms of the EUV concepts of clearing volume and clearing radius, which are then defined and quantitatively calculated.

• 出版日期2016-7