Resist of the month April 2015
High-sensitivity negative resist AR-N 4400-10 for laser direct exposure
The negative resist AR-N 4400-10 was structured with a laser direct imaging system at an exposure wavelength of 405 nm. The figures below show different arrays with column diameters varying from 5 to 50 µm. In this test series, the exposure dose ranged between 7 mJ/cm² and 200 mJ/cm² at a film thickness of 11 µm.
Test areas with different column diameters
40 µm-columns with a dose of 7 mJ/cm²
The sensitivity of the resist is remarkably high. An exposure dose of only 7 mJ/cm² is already sufficiently high to achieve a complete layer build-up. Other negative resists are exclusively designed for i-line exposure (365 nm). The negative resist AR-N 4400-10 thus offers additional fields of application with 405 nm-lasers. Of particular note is for example the structuring of irregularly shaped substrates which are coated with AR-N 4400-10 by dip coating. In this case, exposure is performed with laser light instead of masks.
The extended application possibilities of AR-N 4400-10 prompted us to select this negative resist as resist of the month April.