WET ETCH SUITABLE FOR CREATING SQUARE CUTS IN SI AND RESULTING STRUCTURES

摘要

A single crystal silicon etching method includes providing a single crystal silicon substrate having at least one trench therein. The substrate is exposed to a buffered fluoride etch solution which undercuts the silicon to provide lateral shelves when patterned in the <100> direction. The resulting structure includes an undercut feature when patterned in the <100> direction.