Deep-UV sensitivity of xerogel thin films prepared from solutions of modified titanium alkoxides

Xerogel thin films were prepared from solution of titanium alkoxides (Ti(OiPr)4) complexed with methacrylic acid (MAA) with different molar ratios. The impact of this parameter on their sensitivity to deep-ultraviolet (DUV) was studied. The chemical modifications were characterized by FTIR spectroscopy in ATR mode, and the optical characterization was done by spectroscopic ellipsometry. In this report, condensation of Ti precursor is induced by exposure to DUV which was demonstrated to be less efficient for low MAA:Ti ratios due to lower substitution degrees. More importantly, the chemical resistance to solvent of thin films can be tuned, which is crucial for photolithography applications. To illustrate this, DUV lithography was performed on thin films for two different MAA:Ti ratios and developed with cyclohexanone and ethanol, giving rise to opposite results. Finally, microstructures by DUV were achieved for solutions with the lowest protection degree.

Automated summary

Xerogel thin films were prepared from titanium alkoxides complexed with methacrylic acid, and the impact of MAA:Ti ratio on film sensitivity and chemical resistance was studied. The results showed that films with low MAA:Ti ratio had lower sensitivity but could be tuned for chemical resistance.