Double-sided trench fill for electrical isolation of microelectromechanical system structures

摘要

A method for filling a trench extending through a microelectromechanical system (MEMS) device patterned on a wafer is disclosed. The method involves simultaneously depositing a trench-fill layer of insulating material over a first side of the wafer, over a second side of the wafer, and into the trench extending from the first side to the second side. Further, the width of the trench at the first side of the wafer and/or the second side of the wafer is variable to adjust the rate at which the trench fills.