Disclosed is a fluid ejection device for an inkjet printer that includes a substrate having at least one fluid flow channel configured within a bottom portion of the substrate. Each fluid flow channel of the at least one fluid flow channel is configured by etching the bottom portion. The substrate also includes a plurality of fluid flow vias configured within a top portion of the substrate. Each fluid flow via of the plurality of fluid flow vias is configured by etching the top portion. The each fluid flow via is further configured to be in fluid communication with a corresponding fluid flow channel through an isotropically etched cavity configured below the each fluid flow via and fluidically coupled to the corresponding fluid flow channel. The fluid ejection device also includes a flow feature to layer and a nozzle plate. Further disclosed are methods for fabricating fluid ejection devices.