SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE

摘要

Provided is a semiconductor device wherein deterioration of reliability due to the interface between an upper insulating layer and an element isolating insulating layer is suppressed. The semiconductor device is provided with: a semiconductor substrate; a plurality of multilayer structures each of which is arranged on the semiconductor substrate and has a tunnel insulating layer, a charge accumulating layer, an upper insulating layer and a control electrode stacked therein in sequence; the element isolating insulating layer arranged on each side surface of each multilayer structure; and impurity-doped layers arranged on the semiconductor substrate and between the multilayer structures. The element isolating insulating layer is composed of at least SiO2, SiN or SiON, the upper insulating layer is an oxide which includes Si and at least one metal (M) selected from among the group composed of rare-earth metals, Y, Zr and Hf, and the relationship of Lcharge, Lgatetop is satisfied, where Lcharge, Ltop and Lgate respectively represent the lengths of the charge accumulating layer, the upper insulating layer and the control electrode in the channel length direction.