Patent ID: 7435355
Filing Date: 2008-10-14
Classification: B81B,B81C,B82Y,G01Q,H01L

Abstract:
1. A liquid-based gravity-driven etching technique for controlling structure dimension, comprising the following steps: providing an etching control solution for controlling the structure dimension, wherein the etching control solution has an etchant and an etching-stop solution, the etchant and the etching-stop solution are immiscible, and the etching-stop solution stays below the etchant; providing a substrate having a first surface and a second surface, wherein the first surface has at least one microstructure and at least one thickness control trench surrounding the microstructure, and the second surface has at least one etching trench opposite to the thickness control trench; placing the substrate within the etchant; and etching the substrate by the etchant to communicate the etching trench with the thickness control trench, such that the microstructure is separated from the substrate, thereby falling from the etchant to the etching-stop solution.