METHOD FOR FORMING A CAVITY AND A COMPONENT HAVING A CAVITY

摘要

A method for forming a cavity in a silicon substrate, wherein a surface of the silicon substrate has a tilting angle in relation to a first plane of the silicon substrate and wherein the first plane is a {111} plane of the silicon substrate, and for arranging an etching mask on the surface of the silicon substrate. The etching mask comprises a first retarding structure which projects into the mask opening. The etching mask further comprises a first etching projection region. All further edges of the mask opening outside of the first etching projection region are arranged substantially parallel to the {111} planes of the silicon substrate. As a further step, the method comprises an anisotropic etching of the silicon substrate during a determined etching duration. Thereby an etching rate in the <111> directions of the silicon substrate is lower than in other spatial directions and the first retarding structure is undercut beginning from the first etching projection region in a first undercutting direction. The etching duration is determined such that a cavity is formed in the silicon substrate by the anisotropic etching, said cavity having an opening at the surface of the silicon substrate. The etching duration is determined such that when the etching duration has ended, the first plane of the silicon substrate is substantially exposed and forms a floor surface of the cavity.