Our research team successfully developed a negative resist with high resolution and plasma etching stability in oxygen: Medusa 82. Already with the first samples, it was possible to achieve the properties of HSQ.
With our new development e-beam resist AR-P 6200 (CSAR 62), very fine structures like e.g. 10 nm wide trenches can be manufactured with very high contrast (> 14) and comparably high sensitivity.
Layers with a thickness of 1.5 μm were produced using AR-P 6200.18, thick. As shown by investigations at the KIT (IMT, Dr. Lothar Hahn), allows this layer thickness to generate very regular trenches with a width of 300 nm at a period of 300 nm (see Fig. 1).
Fluorescence is the spontaneous emission of light briefly after a substance is excited by electronic transitions. The emitted light has usually less energy than the previously absorbed light.
The DESIRE process can also be used for electron beam lithography even though certain differences exist between photo and e-beam lithography. Structures are written into the resist layer by means of electrons.
CSAR 62 is routinely used to produce innovative quantum devices at the TU Delft (Mr. Toivo Hensgens, TU-Delft, the Netherlands). For the structures shown below, a 72 nm layer of CSAR 62 was exposed to 100 kV and then developed with amyl acetate.
To evaluate the suitability of various developers for CSAR 62, Dr. Lothar Hahn (Karlsruhe Institute of Technology (KIT), Institute of Microstructure Technology) kindly provided various substrates which had previously been exposed to 100 kV e-beam irradiation (dose variations).
The copolymer composed of methyl methacrylate and methacrylic acid is, in contrast to the pure PMMAs, able to form a 6-membered ring during thermal loading.
In addition to the use in e-beam lithography, the highly sensitive e-beam resist CSAR 62 can also be structured by exposure to UV radiation since the resist strongly absorbs UV radiation in the wavelength range of 190 – 240 nm.
Mr. Y. Nori from Lancaster University (Department of Physics, UK) could very successful generate structures for the production of photonic crystals with CSAR 62.