According to one embodiment, a semiconductor memory device includes: a first memory cell and a second memory cell capable of storing data and coupled in parallel to a bit line; a first word line coupled to the first memory cell; a second word line coupled to the second memory cell and being different from the first word line; and a control circuit. The first memory cell and the second memory cell share a first well region and are opposed to each other, with the first well region interposed. The control circuit is configured, in a first operation, to repeat application of a first voltage to the first word line and the second word line a plurality of times while increasing the first voltage.

According to one embodiment, a semiconductor memory device includes: a first memory cell; a second memory cell; a first word line; a second word line; and a first bit line. The device is configured to execute a first operation, a second operation, and a third operation to write data into the first memory cell. In the first operation, a first voltage is applied to the second word line. In the second operation, after the first operation, a second voltage higher than the first voltage is applied to the second word line. In the third operation, after the second operation, a third voltage higher than the second voltage is applied to the first word line, and a fourth voltage lower than both the second voltage and the third voltage is applied to the second word line.

According to one embodiment, a semiconductor memory device includes: a first memory cell; a second memory cell; a first word line; a second word line; and a first bit line. The device is configured to execute a first operation, a second operation, and a third operation to write data into the first memory cell. In the first operation, a first voltage is applied to the second word line. In the second operation, after the first operation, a second voltage higher than the first voltage is applied to the second word line. In the third operation, after the second operation, a third voltage higher than the second voltage is applied to the first word line, and a fourth voltage lower than both the second voltage and the third voltage is applied to the second word line.

A variety of applications can include memory systems that have one or more memory devices capable of performing memory operations on multiple blocks of memory in response to a command from a host. For example, improvement in erase performance can be attained by erasing multiple blocks of memory by one of a number of approaches. Such approaches can include parallel erasure followed by serial verification in response to a single command. Other approaches can include sequential erase and verify operations of the multiple blocks in response to a single command. Additional apparatus, systems, and methods are disclosed.

In a memory controller configured to control a memory device including a plurality of memory blocks, the memory controller comprising: a memory interface configured to exchange data with the memory device; and a pre-program controller configured to perform a read operation on a last page of a program sequence for a plurality of pages in an erase target memory block when the memory device is in an idle state, and perform a pre-program operation on the erase target memory block according to the result obtained by performing the read operation, wherein the erase target memory block is a memory block on which an erase operation is to be performed among the plurality of memory blocks, and wherein the erase operation on the erase target memory block is performed after the pre-program operation is performed.

An erasing method adapted for a semiconductor memory device is provided. The erasing method includes executing a pre-program process on the semiconductor memory device, executing an erase process on the semiconductor memory device, executing an over-erase verification process on a plurality of memory cells of the semiconductor memory device, detecting a total current consumption of the plurality of memory cells, determining the number of the memory cells to be executed with a soft program process according to the total current consumption, and executing the soft program process on the memory cells based on the number of the memory cells.

A variety of applications can include memory systems that have one or more memory devices capable of performing memory operations on multiple blocks of memory in response to a command from a host. For example, improvement in erase performance can be attained by erasing multiple blocks of memory by one of a number of approaches. Such approaches can include parallel erasure followed by serial verification in response to a single command. Other approaches can include sequential erase and verify operations of the multiple blocks in response to a single command. Additional apparatus, systems, and methods are disclosed.

According to one embodiment, a semiconductor memory device includes: a first memory cell and a second memory cell capable of storing data and coupled in parallel to a bit line; a first word line coupled to the first memory cell; a second word line coupled to the second memory cell and being different from the first word line; and a control circuit. The first memory cell and the second memory cell share a first well region and are opposed to each other, with the first well region interposed. The control circuit is configured, in a first operation, to repeat application of a first voltage to the first word line and the second word line a plurality of times while increasing the first voltage.

According to one embodiment, a semiconductor memory device includes: a first memory cell; a second memory cell; a first word line; a second word line; and a first bit line. The device is configured to execute a first operation, a second operation, and a third operation to write data into the first memory cell. In the first operation, a first voltage is applied to the second word line. In the second operation, after the first operation, a second voltage higher than the first voltage is applied to the second word line. In the third operation, after the second operation, a third voltage higher than the second voltage is applied to the first word line, and a fourth voltage lower than both the second voltage and the third voltage is applied to the second word line.

An erasing method adapted for a semiconductor memory device is provided. The erasing method includes executing a pre-program process on the semiconductor memory device, executing an erase process on the semiconductor memory device, executing an over-erase verification process on a plurality of memory cells of the semiconductor memory device, detecting a total current consumption of the plurality of memory cells, determining the number of the memory cells to be executed with a soft program process according to the total current consumption, and executing the soft program process on the memory cells based on the number of the memory cells.