| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor memory device, wherein charge storage density becomes max by analyzing the charge storage density as a function of composition of Al, in a charge storage layer of Al-rich Al<SB>2</SB>O<SB>3</SB>. SOLUTION: A tunnel barrier layer, a charge storage layer, block barrier layer and a gate electrode are laminated in this order on the top surface of a semiconductor substrate, and electrons are stored in a localized level of the charge storage layer, thereby a threshold voltage of a transistor is varied, in the semiconductor memory. This memory has a constitution wherein the charge storage layer is aluminum oxide of excess-aluminum (Al-rich Al<SB>2</SB>O<SB>3</SB>), and composition of the aluminum is set in a predetermined range, and the charge storage density of the charge storage layer becomes a predetermined value or above including the maximal value (maximum value). COPYRIGHT: (C)2011,JPO&INPIT |
