In one embodiment, a fluid ejection device includes a substrate with a fluid slot and a membrane adhered to the substrate that spans the fluid slot. A resistor is disposed on top of the membrane over the fluid slot, and a fluid feed hole next to the resistor extends through the membrane to the slot. A shelf extends from the edge of the resistor to the edge of the feed hole, and a passivation layer covers the resistor and part the shelf. An etch-resistant layer is formed partly on the shelf and in between the fluid feed hole and the resistor.