Thermostable photoresists

Many applications demand coatings with excellent thermal stability. Structures of the temperature-stable negative resist SX AR-N 4340/6 are able to withstand temperatures of up to 350 °C with high shape accuracy (Fig. 1); merely shrinkage of up to 20% is observed (Fig. 2).

Fig. 1  REM-image of  SX AR-N 4340/6 structure tempered at 350 °C with smooth surface and sharp edges

Fig. 2  Temperature-dependent shrinkage, measured with Dektak 150

Structures of the new thermostable positive resists SX AR-P 3500/8 also show a great resistance to very high temperatures as they occur for example in intensive etching or implantation processes. Most commercially available removers easily dissolve resist layers after thermal loads of up to 130 ° C. At higher temperatures however, the aqueous alkaline remover AR 300-73 has to be used. Hardened structures (above 150 ° C) are then inert to solvents, which enables applications in microfluidics.