Thermally stable two-layer lift-off systems
The Resist Wiki article “Positive two-layer lift-off systems” describes the principle of these two-layer systems. During the application of lift-off structures, temperatures above 150 °C occur frequently, for example during sputtering. If the usual photo resists are used as top layer, the lift-off structure melts and thus becomes useless for the process.
Using the thermostable positive resist SX ARP 3500/8 as top layer, however, yields a heat-resistant lift-off structure which also withstands sputtering processes. See Resist-Wiki “Negative two-layer lift-off system” and “Thermostable photo resists”.
Overview Photoresists- Positive