Chemically amplified deep ultraviolet resist for positive tone ion exposure

The positive tone deep ultraviolet resist UV II HS-0.6 (Shipley) has been evaluated for ion exposure in the ion projector at the Fraunhofer Institute in Berlin. The chemically amplified resist showed extremely high sensitivity of 1*1012 H+ ions/cm2 at an ion energy of 75 keV. The contrast number was 11. Smallest lines with 65 nm linewidth could be delineated in 140-nm-high resist. At higher resist thickness of 370 nm, lines down to 70 nm were stable showing aspect ratios of >4. The exposure latitude at 100 nm nominal linewidth was +or-10% dose variation for a +or-10% linewidth change.