Word line zone based unselect word line bias to enable single-side gate-induced drain leakage erase
Embodiments disclosed herein are directed to performing a single-side gate-induced drain leakage (GIDL) erase operation. Control circuitry may be configured to perform a single-side GIDL erase operation on a memory block in which a selected sub-block is erased while an unselected sub-block is not erased. During the single-side GIDL erase operation, the control circuitry may be configured to apply a first unselect bias voltage to a first set of word lines of the unselected sub-block, where the first set of word lines is associated with a first word line zone and the first word line zone is associated with an unselect bias voltage, and apply a second unselect bias voltage to a second set of word lines of the unselected sub-block, where the second set of word lines is associated with a second word line zone and the second word line zone is associated with another unselect bias voltage.
1 . A memory device, comprising:
a memory block including a plurality of sub-blocks, wherein the memory block has a tiered arrangement in which the plurality of sub-blocks includes sub-blocks in different tiers, each of the plurality of sub-blocks including a plurality of word lines; and
control circuitry configured to perform a single-side gate-induced drain leakage (GIDL) erase operation on the memory block in a sub-block mode in which a selected sub-block of the plurality of sub-blocks in the memory block is erased while an unselected sub-block in a first tier of the plurality of sub-blocks in the memory block is not erased, the control circuitry further configured to, during the single-side GIDL erase operation:
apply a first unselect bias voltage to a first set of word lines of the unselected sub-block in the first tier, wherein the first set of word lines is associated with a first word line zone of a plurality of word line zones, and wherein each word line zone of the plurality of word line zones is associated with an unselect bias voltage; and
apply a second unselect bias voltage to a second set of word lines of the same unselected sub-block in the first tier, wherein the second set of word lines is associated with a second word line zone of the plurality of word line zones,
wherein the first word line zone is associated with a first memory hole diameter of the unselected sub-block, the second word line zone is associated with a second memory hole diameter of word lines in the unselected sub-block, and the first memory hole diameter is less than the second memory hole diameter.
2 . The memory device of claim 1 , the control circuitry further configured to:
identify a word line zone of the plurality of word line zones corresponding to a set of word lines; and
set an unselect bias voltage related parameter corresponding to the set of word lines based on the identified word line zone.
3 . The memory device of claim 1 , wherein the first unselect bias voltage is more positive than the second unselect bias voltage.
4 . The memory device of claim 1 , wherein the second unselect bias voltage is more negative than the first unselect bias voltage.
5 . A method of operating a non-volatile semiconductor memory device, the method comprising:
performing a single-side gate-induced drain leakage (GIDL) erase operation on a memory block in a sub-block mode in which a selected sub-block of a plurality of sub-blocks in the memory block is erased while an unselected sub-block in a first tier of the plurality of sub-blocks in the memory block is not erased, wherein the memory block has a tiered arrangement in which the plurality of sub-blocks includes sub-blocks in different tiers; and
during the single-side GIDL erase operation:
applying a first unselect bias voltage to a first set of word lines of the unselected sub-block in the first tier, the first set of word lines associated with a first word line zone of a plurality of word line zones, each word line zone of the plurality of word line zones associated with an unselect bias voltage; and
applying a second unselect bias voltage to a second set of word lines of the same unselected sub-block in the first tier, the second set of word lines associated with a second word line zone of the plurality of word line zones.
6 . The method of claim 5 , the method further comprising:
identifying a word line zone of the plurality of word line zones corresponding to a set of word lines; and
setting an unselect bias voltage related parameter corresponding to the set of word lines based on the identified word line zone.
7 . The method of claim 5 , wherein the first unselect bias voltage is more positive than the second unselect bias voltage.
8 . The method of claim 5 , wherein the second unselect bias voltage is more negative than the first unselect bias voltage.
9 . An apparatus, comprising:
a memory block including a plurality of sub-blocks, wherein the memory block has a tiered arrangement in which the plurality of sub-blocks includes sub-blocks in different tiers,
each of the plurality of sub-blocks including a plurality of word lines; and
a means for performing a single-side gate-induced drain leakage (GIDL) erase operation on the memory block in a sub-block mode in which a selected sub-block of the plurality of sub-blocks in the memory block is erased while an unselected sub-block in a first tier of the plurality of sub-blocks in the memory block is not erased, the means for performing the single-side GIDL erase operation being configured to, during the single-side GIDL erase operation:
apply a first unselect bias voltage to a first set of word lines of the unselected sub-block in the first tier, the first set of word lines associated with a first word line zone of a plurality of word line zones, each word line zone of the plurality of word line zones associated with an unselect bias voltage; and
apply a second unselect bias voltage to a second set of word lines of the same unselected sub-block in the first tier, the second set of word lines associated with a second word line zone of the plurality of word line zones.
10 . The apparatus of claim 9 , the means for performing the single-side GIDL erase operation being further configured to:
identify a word line zone of the plurality of word line zones corresponding to a set of word lines; and
set an unselect bias voltage related parameter corresponding to the set of word lines based on the identified word line zone.
11 . The apparatus of claim 9 , wherein the first unselect bias voltage is more positive than the second unselect bias voltage.