Resist of the month April 2013:
Positive e-beam resist CSAR 62 – an alternative to ZEP 520
Users cherish the specific properties of ZEP 520, while service and prices are rather feared. This was a strong motivation for us to develop a similar and already now improved e-beam resist in the interest of our customers.
In already well-established cooperation with the IDM e.V. Teltow and the MLU Halle, new polymers composed of methyl styrene and halogen acrylates were at first synthesised and subsequently tested with electron beam lithography. An increase in sensitivity was achieved by addition of halogenated acid generators. We thus chose the name CSAR ( c hemical s emi- a mplified r esist) for this development. The first results were recently published in our AR NEWS (26 th issue).
An outstanding feature is already now the resolution which could be realised for 10 nm grooves at a film thickness of 180 nm (see Fig. 1). Also remarkable is that 10 nm lift-off structures can easily be generated in a one-layer process (see Fig. 2). Additional optimisation works aimed to increase sensitivity and plasma etch stability are in the final stages of development and promise further very good results.
In a few weeks, Allresist will be able to provide the first resist samples for interested customers. Our well-known good service and prompt delivery is also maintained for the new CSAR 62.
These highly interesting and important results prompted us to select our new development CSAR 62 as resist of the month.
Fig. 1: 10 nm resolution with SX AR-P 6200/2 at a film thickness of 180 nm
Fig. 2: Chromium-structures after lift-off process with SX AR-P 6200/2 (artwork)