Erase for non-volatile storage

摘要

Techniques are disclosed herein for erasing non-volatile storage elements. A sequence of increasing erase voltages may be applied to a substrate. The select line may be floated and many of the word lines may be held at a low voltage (e.g., close to 0V). However, the voltage applied to an edge word may be increased in magnitude relative to a previous voltage applied to the edge word line for at least a portion of the sequence of erase voltages. The edge word line could be the word line that is immediately adjacent to the select line. The increasing voltage applied to the edge word line may prevent or reduce damage to oxides between the select line and edge word line. It may also help to regulate the e-field across a tunnel oxide of memory cells on the edge word line.

主权项

1. A method for operating a non-volatile storage device, the method comprising:
applying a sequence of erase voltages to a group of non-volatile storage elements that increase in magnitude as the sequence progresses, the group of non-volatile storage elements associated with a plurality of word lines and a select line, the plurality of word lines including a first edge word line that is adjacent to the select line; floating the select line while applying each of the erase voltages in the sequence; and applying a voltage to the first edge word line while applying each of the erase voltages in the sequence, the voltage applied to the first edge word line increases in magnitude relative to a previous voltage applied to the first edge word line for at least a portion of the sequence of erase voltages.