Patent · US Active

Semiconductor memory device and manufacturing method thereof

US8981455B2 · kind B2 · utility

0Cited by
3References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 27, 2013
Grant dateMar 17, 2015
Priority date
Expiry dateFeb 27, 2033

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D64/035

Abstract

In accordance with an embodiment, a semiconductor memory device includes a substrate with a semiconductor layer and memory cells on the semiconductor layer. Each memory cell includes a laminated body on the semiconductor layer, a gate insulating film on the laminated body, and a control gate on the gate insulating film. The laminated body includes a tunnel insulating film and a floating gate subsequently laminated in a direction vertical to a front surface of the substrate for N (a natural number equal to or above 2) times. A dimension of a top face of any floating gate in a second or subsequent layer is smaller than a dimension of a bottom surface of the floating gate in the lowermost layer in at least one of a first direction parallel to the front surface of the substrate and a second direction crossing the first direction.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.