Flash Memory Devices and Prefetch Methods Thereof

1 . A storage device, comprising:

a flash memory array, comprising a plurality of blocks, wherein the blocks are configured to store data; and

a controller, scanning the flash memory during an idle time to confirm accuracy of the data stored in the flash memory array.

2 . The storage device of claim 1 , wherein the idle time is a period of time between when the storage device is initialized and when a host is initialized.

3 . The storage device of claim 1 , wherein the idle time is a period of time between when the storage device is initialized and when an access instruction is received from the host.

4 . The storage device of claim 1 , wherein when the controller scans the flash memory array, the controller selectively scans at least one of pages of each of the blocks to determine whether a number of error bits in any of the scanned page(s) exceeds a threshold.

5 . The storage device of claim 4 , wherein when the number of error bits in any of the pages exceeds the threshold, the controller performs a refresh process on the flash memory array.

6 . The storage device of claim 4 , wherein when the number of error bits in any of the pages exceeds the threshold, the controller performs a refresh process on the blocks corresponding to the pages with the excessive number of error bits.

7 . A refresh method, adopted in a storage device, wherein the refresh method comprises:

initializing the storage device;

scanning the storage device during an idle time to determine accuracy of data stored in the storage device; and

entering a stand-by state to receive an access instruction.

8 . The refresh method of claim 7 , wherein the idle time is a period between when the storage device is initialized to when the host is initialized.

9 . The refresh method of claim 7 , wherein the idle time is a period between when the storage device is initialized and when an access instruction is received from the host.

10 . The refresh method of claim 7 , wherein the storage device comprises a flash memory array, wherein the flash memory array comprises a plurality of blocks, wherein the step of scanning the storage device during the idle time to determine the accuracy of the data stored in the storage device further comprises:

scanning at least one of the pages of each of the blocks;

determining whether a number of error bits in any of the scanned page(s) exceeds a threshold; and

when the number of error bits in any of the pages exceeds a threshold, performing a refresh process on the flash memory array.

11 . The refresh method of claim 7 , wherein the storage device comprises a flash memory array, and the flash memory array comprises a plurality of blocks, wherein the step of scanning the storage device during the idle time to determine the accuracy of the data stored in the storage device further comprises:

scanning at least one of the pages of each of the blocks;

determining whether the number of error bits in the scanned page(s) exceeds a threshold; and

when the number of error bits in any of the pages exceeds a threshold, performing a refresh process on the blocks corresponding to the pages with the excessive number of error bits.