ALIGNED PIPE ARRAYS FORMATION BY SILICON ANODIC ETCHING

A simple technique is described here that produces aligned curved or s traight arrays of pipes. This opens the way to produce complete system s (electronic, photonic and fiber optic connectors) from silicon with large scale fabrication techniques. Our strategy in creating parallel pipes is to use high current densities (similar to 100 mA/cm(2)) silic on anodization in HF solutions, in a cell where the current direction and the preferential etching directions are not coincident in (111) si licon substrates. The etched structure in a nanoscale range was observ ed using atomic force microscopy, which shows steps. In a macroscopic scale steps were observed in the walls of arrays of tenths of millimet ers diameter pipes. Pores arrays were obtained forming a similar to 90 degrees angle with the current direction. Molecular mechanics simulat ions of the pipe wall structure show that a preferential etching along the < 100 > direction and passivation of the (111) planes are the mec hanisms responsible for the formation of pore arrays structure. (C) 19 98 American Vacuum Society.