Characterization of 248nm Deep Ultraviolet (DUV) Photoresist after Ion Implantation

Abstract

The elemental and structural changes of 248nm DUV photoresist induced by arsenic implantation with high dose and different acceleration energies were studied. For this purpose different analytical techniques were combined. An investigation of the capabilities of the Micro Raman Spectroscopy for analysis of ion implanted photoresist (II-PR) revealed that the method is unreliable for the characterization of II-PR since it induces a modification of the top crust layer. Moreover, alternative methods were used for characterization of the crust. The crust structure was indentified as cross-linked PR by Solid State Nuclear Magnetic Resonance. No experimental evidence for presence of amorphous carbon was found. Furthermore, the elemental composition and mechanical properties of the crust as a function of the implant energy were discussed as a measure for the cross-linking density. Finally, the dopant role in the cross-link process was considered.