The capability of using a focused ion beam (FIB) for milling of submicron channel structures on a gold layer is investigated. A double-charged arsenic (As2+) FIB is adopted to assess the effect of the dwell time on the final profiles of the milled structures. A single-pass milling, which creates relatively shallow microchannels, is conducted in order to estimate the corresponding milling yields. The condition to provide a uniform ion flux in milling is first studied. The procedure on conducting the milling experiment is then presented. The atomic force microscope (AFM) is applied for measuring the profiles of the milled channels. Based on the AFM measurements, the milling yields have been estimated and compared with the sputtering yields predicted by a more sophisticated numerical simulation. The milling yield for the relatively shallow microchannels presently considered has been discovered to be roughly equal to the predicted normal-incidence sputtering yield. Consistence has also been found as the present findings have been compared with other channel milling studies, which had used different ion beams and target materials. FIB milling has been shown to be an effective tool for making submicron channels in gold layers. (C) 2004 American Vacuum Society.