It is demonstrated that the sputter etching of a Cu–Ag sandwich using a focused Ar+‐ion beam creates a crater covered with densely distributed microprojections, offering a crater‐edge profile poor in resolution. The projections grew in a variety of shapes, ranging from a rod to a wide‐angle cone, and their number density reached ∼109/cm2. The dimensions of the projections were also not uniform, increasing discernibly with depth. It is believed that an enhanced surface mobility of Cu and Ag atoms during the sputtering played a role in growing the projections.