Experimental study of three-dimensional microfabrication by focused ion beam technology

Combined with experimental milling, three-dimensional (3D) microfabrication by focused ion beam (FIB) technology has been studied. Rules among limitin g aperture size, dwell time, retrace time, tail of Gaussian distribution, e tc., have been analyzed in terms of experimental results. Some phenomena ar e explained from the theoretical point of view. In addition, influence of r edeposition for the sidewall root of microstructure in the process of milli ng is analyzed, and the avoidance methods are used in the meantime. It was proved by experiment that beam current (representing ion beam energy) and b eam spot size play an important role in the etching process. Nonlinear vari ation of these parameters led to the broadening of edge periphery and redep osition at the root of the sidewall. On the other hand, milling order is vi tal for the 3D microfabrication result by FIB sputtering due to the redepos ition effect and profile broadening effect. (C) 2000 American Institute of Physics. [S0034-6748(00)65302-9].