Sonos memory cell structure and fabricating method of the same

Abstract

An SONOS memory cell includes a silicon substrate. A tunnel silicon oxide layer, a silicon nitride layer and a silicon oxide layer are disposed from bottom to top on the silicon substrate. The silicon oxide layer includes two first silicon oxide layers and a second silicon oxide layer. A thickness of the silicon oxide layer is smaller than a thickness of each of the first silicon oxide layers. A control gate covers and contacts the silicon oxide layer. A first source/drain doping region and a second source/drain doping region are respectively disposed at two sides of the control gate. The silicon oxide layer has a cross section. The second silicon oxide layer is sandwiched between the two first silicon oxide layers on the cross section.