Win-San Khwa, Meng-Fan Chang, et al.
ISSCC 2016
Inherent cell variation of phase change memory is difficult to control by material or device engineering alone. We previously reported R-I curve shift detection scheme as a good method for monitoring PCM cell characteristics. This paper extends that concept and proposes a Stress-trim procedure to tighten R-I characteristics for PCM MLC operation. By leveraging the right-shift phenomena of PCM R-I curves, we demonstrated that Stress-trim can effectively reduce cell variation to improve MLC performance. A MLC program current amplitude range reduction of 40% and MLC time to failure extension of nearly 150X are achieved.
Win-San Khwa, Meng-Fan Chang, et al.
ISSCC 2016
Sangbum Kim, Pei-Ying Du, et al.
VLSI-TSA 2012
Win-San Khwa, Meng-Fan Chang, et al.
IEEE Electron Device Letters
Jau-Yi Wu, Win-San Khwa, et al.
VLSI Technology 2015