abstract |
A method of determining the time to release of a movable feature in a multilayer substrate of silicon-containing materials including alternate layers of polysilicon and silicon oxide wherein a mass monitoring device determines the mass of a released feature, and the substrate is etched with anhydrous hydrogen fluoride until the substrate mass is equivalent to that of the released movable feature when the etch time is noted. A suitable mass monitoring device is a quartz crystal microbalance. |