Extreme ultraviolet patterning of tin-oxo cages

Abstract

Abstract. We report on the extreme ultraviolet (EUV) patterning performance of tin-oxo cages. These cage molecules were already known to function as a negative tone photoresist for EUV radiation, but in this work, we significantly optimized their performance. Our results show that sensitivity and resolution are only meaningful photoresist parameters if the process conditions are optimized. We focus on contrast curves of the materials using large area EUV exposures and patterning of the cages using EUV interference lithography. It is shown that baking steps, such as postexposure baking, can significantly affect both the sensitivity and contrast in the open-frame experiments as well as the patterning experiments. A layer thickness increase reduced the necessary dose to induce a solubility change but decreased the patterning quality. The patterning experiments were affected by minor changes in processing conditions such as an increased rinsing time. In addition, we show that the anions of the cage can influence the sensitivity and quality of the patterning, probably through their effect on physical properties of the materials.

EUV photofragmentation study of hybrid nonchemically amplified resists containing antimony as an absorption enhancer

“…[2][3][4] The concepts to be considered, among others, include essentially non-chemically amplied resists (n-CARs) and hybrids. [4][5][6][7][8][9][10][11][12][13][14][15] The design paradigm has to incorporate the basic principles of conventional resists superimposed with the specic requirements of EUVL for attaining the lower nodes. 12,15,16 The interaction of the resist thin lms with high energy EUV photons (13.5 nm) is a very complex process triggered by EUV radiation that breaks the chemical bonds and simultaneously produces ablation and a high yield of secondary electrons.…”

Photo-induced Fragmentation of a Tin-oxo Cage Compound

“…The tin-oxo cage [(nBuSn) 12 O 14 (OH) 6 ] 2+ (X -) 2 , where Xdenotes a counterion, was prepared according to previously described methods [10,11,19], starting from the commercially available nBuSnOOH (Sigma Aldrich) and p-toluene sulfonic acid (Sigma Aldrich) to yield [(nBuSn) 12 O 14 (OH) 6 ](pTos) 2 which was then exchanged with aqueous base to yield [(nBuSn) 12 O 14 (OH) 6 ](OH) 2 which we call TinOH. NMR and IR spectra agreed with the literature.…”

“…An example of such a material is the tin-oxo cage (see Fig. 1) [9][10][11]. This cage consists of a tin-oxo core with 12 organic groups (in the present case nbutyl chains) attached to the tin atoms.…”

Nanolithographic Top‐Down Patterning of Polyoxovanadate‐Based Nanostructures with Switchable Electrical Resistivity

“…However, the resulting silicon oxide nanostructures offer limited chemical reactivity, so that next‐generation resists with added functionalities (e. g. redox‐ or acid/base‐reactivity) are required to open new application scenarios, such as catalysis, or integration in electrical circuits. Pioneering studies in this direction have developed alternative resists with (photo)catalytic or redox‐properties based on metal‐oxide organic clusters, [17] metal‐oxide cores, [18] as well as molecular metal oxides (polyoxometalates, POMs) [15a,19] …”