Patent ID: 8564038
Filing Date: 2013-10-22
Classification: H01L

Abstract:
1. A nonvolatile semiconductor memory device comprising: a gate insulating film provided on a semiconductor substrate; a floating gate layer provided on the gate insulating film; an inter-gate insulating film provided on the floating gate layer; a control gate layer provided on the inter-gate insulating film; a first insulating film provided on the semiconductor substrate; a first conductive layer provided on the first insulating film; a second insulating film provided on the first conductive layer; a second conductive layer provided on the second insulating film and connected to the first conductive layer via a first opening portion formed in the second insulating film; a first contact connected to the second conductive layer; a third conductive layer provided on the second insulating film and connected to the first conductive layer via a second opening portion formed in the second insulating film; a second contact connected to the third conductive layer; a fourth conductive layer provided on the second insulating film and connected to the first conductive layer via a third opening portion formed in the second insulating film; and a third contact connected to the fourth conductive layer, wherein the floating gate layer and the first conductive layer are made of the same material, and the control gate layer, the second conductive layer, the third conductive layer, and the fourth conductive layer are made of the same material.