US 11,854,611 B2
Aggressive quick-pass multiphase programming for voltage distribution state separation in non-volatile memory
Harish Singidi, Fremont, CA (US); Amiya Banerjee, Karnataka (IN); and Shantanu Gupta, Freemont, CA (US)
Assigned to SANDISK TECHNOLOGIES LLC, Addison, TX (US)
Filed by SANDISK TECHNOLOGIES LLC, Addison, TX (US)
Filed on May 21, 2021, as Appl. No. 17/326,417.
Prior Publication US 2022/0375513 A1, Nov. 24, 2022
Int. Cl. G11C 11/34 (2006.01); G11C 11/56 (2006.01); G11C 16/04 (2006.01); G11C 16/16 (2006.01); G11C 16/34 (2006.01); G11C 16/10 (2006.01); H10B 41/27 (2023.01); H10B 43/27 (2023.01)
CPC G11C 11/5628 (2013.01) [G11C 11/5635 (2013.01); G11C 11/5671 (2013.01); G11C 16/0483 (2013.01); G11C 16/10 (2013.01); G11C 16/16 (2013.01); G11C 16/3445 (2013.01); G11C 16/3459 (2013.01); H10B 41/27 (2023.02); H10B 43/27 (2023.02)] 20 Claims
OG exemplary drawing
 
1. A data storage system, comprising:
a storage medium including a plurality of memory cells; and
control circuitry coupled to the storage medium, configured to program the plurality of memory cells using a multiphase programming scheme including a first programming phase and a second programming phase immediately following the first programming phase;
wherein the first programming phase includes programming a first set of voltage distributions of the plurality of memory cells by applying a first plurality of program pulses to word lines of the plurality of memory cells; and
wherein the second programming phase includes:
programming a second set of voltage distributions by applying a second plurality of program pulses to the word lines of the plurality of memory cells, wherein the second set of voltage distributions includes more voltage distributions than the first set of voltage distributions;
maintaining a margin of separation between two adjacent voltage distributions of the second set of voltage distributions after each of the second plurality of program pulses; and
allowing overlap between voltage distributions other than the two adjacent voltage distributions of the second set of voltage distributions after one or more of the second plurality of program pulses;
wherein a read reference voltage for lower page or middle page data associated with one or more of the second set of voltage distributions is in the margin of separation between the two adjacent voltage distributions.