公开(公告)号：EP1746604A1

公开(公告)日：2007-01-24

申请号：EP05106783.3

申请日：2005-07-22

Applicant: STMicroelectronics S.r.l. ,  Hynix Semiconductor Inc.

Inventor： Bovino, Angelo ,  Altieri, Vincenzo ,  Ravasio, Roberto ,  Micheloni, Rino ,  De Matteis, Mario

IPC: G11C11/56

CPC classification number: G11C16/0483 ,  G11C11/5628 ,  G11C2211/5641

Abstract: Multi-level programming (30-42) allows for writing a first and a second bit in selected cells (3) by separately programming (30-32) a first bit (LSB) from a second bit (MSB). Programming (30-32) of the first bit determines a shifting (32) from a first threshold level (A) to a second threshold level (B); programming (36-42) of the second bit requires a preliminary reading (36-40) to detect whether the first bit (LSB) has been modified; performing a first writing step (42) to bring the cell to a third threshold voltage (C) if the first bit has been modified and performing a second writing step (42) to bring the selected cell to a fourth threshold voltage (D) different from the third threshold level if the first bit has not been modified. The memory array (2) divided into a first portion (2a) where data are stored using multiple threshold levels corresponding to a plurality of bits, and a second portion (2b) where data are stored using two threshold levels corresponding to a single bit. For increasing reading and program reliability, during preliminary reading (40) of the second portion (2b) a reading result is forced to correspond to the first threshold level.

Abstract translation: 多级编程（30-42）允许通过从第二位（MSB）单独编程（30-32）第一位（LSB）来在所选单元（3）中写入第一位和第二位。 第一位的编程（30-32）确定从第一阈值电平（A）到第二阈值电平（B）的移位（32）; 第二位的编程（36-42）需要初步读取（36-40）来检测第一位（LSB）是否已被修改; 执行第一写入步骤（42），如果第一位已被修改并使单元进入第三阈值电压（C），并执行第二写入步骤（42）以使所选择的单元达到不同的第四阈值电压（D） 如果第一位未被修改，则从第三阈值水平。 存储器阵列（2）被划分为第一部分（2a），其中使用与多个位相对应的多个阈值级别存储数据;以及第二部分（2b），其中使用与单个位对应的两个阈值电平存储数据。 为了增加读取和编程可靠性，在第二部分（2b）的初步读取（40）期间，读取结果被迫对应于第一阈值水平。

公开(公告)号：EP1746604B1

公开(公告)日：2009-02-04

申请号：EP05106783.3

申请日：2005-07-22

Applicant: STMicroelectronics S.r.l. ,  Hynix Semiconductor Inc.

Inventor： Bovino, Angelo ,  Altieri, Vincenzo ,  Ravasio, Roberto ,  Micheloni, Rino ,  De Matteis, Mario

IPC: G11C11/56

CPC classification number: G11C16/0483 ,  G11C11/5628 ,  G11C2211/5641