Ion beam irradiation of thin CaF2 films:: a study of lithographic properties

THIN SOLID FILMS

卷:373

Article; Proceedings Paper

Zehe, A ; Ramírez, A

关键词: dielectrics;    epitaxy;    fluorine (fluorides);    ion bombardment;   

DOI  :  10.1016/S0040-6090(00)01106-8

来源: Elsevier

【 摘 要 】

The technological track to ever smaller devices in very- and ultra-high-scale integration schemes with feature sizes lower than 1 mum, carries photolithographic methods to physical limits, and is claiming a transition to lower wavelength or particle irradiation. New resist materials and exposure techniques are under study. Earth alkaline fluorides, such as CaF2, BaF2, and SrF2, decompose under electron and ion irradiation by desorbing fluor, and oxidizing the remaining earth alkaline metal under the presence of oxygen. The solubility of the oxidized areas is then modified. The present paper deals with resist properties of CaF2 under ion beam exposition with Ar+-, He+-, Si+- and O+-ions. RES measurements are applied in order to determine modifications in the him composition, Positive and negative resist behavior is found in water and dilute HCl, respectively. Both the change of chemical composition and the pattern characteristics correlate with the energy deposition of implanted ions. Characteristic lithographic curves are shown. (C) 2000 Elsevier Science S.A. All rights reserved.

【 授权许可】

Free