METHOD OF MANUFACTURING SEMICONDUCTOR DEVICE

摘要

The big loss of the element isolation film can be prevented in the recess gate formation. The signal interference and the short between the adjacent gates due to the loss of the element isolation film can be prevented. The method of manufacturing the semiconductor device is provided. A step is for forming a trench in an element isolation region of a semiconductor substrate(200) having the active area and element isolation region. A step is for forming the element isolation film(203) by burying the SOG film(202) in the trench. A step is for successively forming the silicon oxide film and phospho silicate glass film on the semiconductor substrate including the element isolation film. A step is for exposing the gate forming area of the active area by etching successively the phospho silicate glass film and silicon oxide film. A step is for forming a groove(H) by etching the exposed gate forming area of the semiconductor board using the etched phospho silicate glass film as the etching barrier. A step is for forming a gate on the semiconductor substrate including the groove.