Abstract: Based on the mechanism of inductively coupled plasma (ICP) etching, the micromachining processing of 3D micro tensile beams is researched in the light of the structure characteristics of the thermal silicon dioxide micro-tensile beams and with the purpose of solving the main problems in the processing. The influences of ICP etching process parameters on etching quality, including micro loading effect and aspect ratio effect in existence, are presented. The micromachining processing of the beams is introduced in detail. The pivotal procedure is double-masks-twice-ICP etching to form stair-opening structures and to obtain the free-standing thermal silicon dioxide beams on the surface of silicon. Using the high selectivity of single crystal silicon in ICP etching, the processing method is applicable in the fabrication of micro tensile beams with various films.

Key words: Inductively coupled plasma etching, Micro tensile beams, Stair-opening structure, Thermal silicon dioxide film