Gas-assisted etching of niobium with focused ion beam

Gas-assisted etching (GAE) of niobium with focused ion beam (FIB) has been investigated systematically in I2 and XeF2 gas atmosphere. The etching parameters which have been examined are ion beam current, beam dwelling time, beam overlap and gas species. It has been found that the beam overlap has no effect on the FIB etching of niobium, but significant effect when GAE is introduced. While the etching rate increases in general with ion beam current, the GAE effect is stronger with a smaller ion beam current. The shorter the dwelling time, the greater the GAE rate compared to FIB etching without GAE.