Colleagues, I'm manufacturing micro-capacitors. In doing so I put down an AlN layer as a dielectric between the plates via reactive sputtering. During manufacturing I need to pattern the AlN-surface with Photoresist AZ9260. The problem I'm having at this step, is, that my Developer AZ400K 1:4 (Developer : H2O) @ 27C takes off the AlN layer for some reason. It attacks it and makes it peel off. However, XRD shows a clear 0002-peak and EDX is fine. The layer is 2microns thick. Underneath the AlN you can find Cu, or Al as a capacitor plate or highly B-doped Si. I need to mention here that I don't have the possibility to take off the native oxide with a plasma prior to AlN deposition. So, what is the problem with my AlN layer and how can I improve my layer? Might the native oxide on the above mentioned materials cause that effect? I appreciate your help Best Regards, Sebastian