Patent ID: 6812525
Filing Date: 2004-11-02
Classification: H01L

Abstract:
A semiconductor device, comprising:a silicon substrate, the substrate including: a top surface; a first isolation trench having a structure including opposing sidewalls, the sidewalls spaced from each other by a width at the top surface, and the sidewalls extending from the top surface into the substrate to a trench bottom at a depth, the depth being greater than the width and the sidewalls being closed along opposite ends by end surfaces, the end surfaces opposing each other and spaced from each other by a length, the length being greater than the width; and a drift region beside the trench, the drift region having a first conductivity-type, and a portion of the substrate adjacent to the sidewalls being doped with a dopant having a second conductivity-type, the second conductivity-type being of opposite conductivity to the first conductivity-type of the drift region; a sealing cap, covering the top of the trench such that flow of gas is prevented into or out of a sealed space defined by the sealing cap and the structure of the trench; and the sealed space having a pressure less than atmospheric pressure.