Hi, everyone. I am trying to etch SiO2 layer by RIE dry etching using photoresist (s1827) as the etching mask. Because the SiO2 layer is as thick as 1 um, I need to do the RIE dry etching for long time. However when I extend the etching time more than 15 mins, the photoresist becomes carbonized. Carbonzied photoresist is hard to remove without attacking the GaAs device under the SiO2. Are there other SiO2 etching recipes without carbonizing the photoresist? Or are there some way to strip the carbonized photoresist without destroying the device? Thank you! Weiquan