n-Type Doped Conjugated Polymer for Nonvolatile Memory

Wen-Ya Lee; Hung-Chin Wu; Chien Lu; Benjamin D Naab; Wen-Chang Chen; Zhenan Bao

doi:10.1002/adma.201605166

n-Type Doped Conjugated Polymer for Nonvolatile Memory

Adv Mater. 2017 Apr;29(16). doi: 10.1002/adma.201605166. Epub 2017 Feb 24.

Authors

Wen-Ya Lee^{1

2}, Hung-Chin Wu^{2

3}, Chien Lu³, Benjamin D Naab², Wen-Chang Chen³, Zhenan Bao²

Affiliations

¹ Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei, 106, Taiwan, Republic of China.
² Department of Chemical Engineering, Stanford University, 443 Via Ortega, Stanford, CA, 94305, USA.
³ Department of Chemical Engineering, National Taiwan University, Taipei, 10617, Taiwan, Republic of China.

PMID: 28234405
DOI: 10.1002/adma.201605166

Abstract

This study demonstrates a facile way to efficiently induce strong memory behavior from common p-type conjugated polymers by adding n-type dopant 2-(2-methoxyphenyl)-1,3-dimethyl-2,3-dihydro-1H-benzoimidazole. The n-type doped p-channel conjugated polymers not only enhance n-type charge transport characteristics of the polymers, but also facilitate to storage charges and cause reversible bistable (ON and OFF states) switching upon application of gate bias. The n-type doped memory shows a large memory window of up to 47 V with an on/off current ratio larger than 10 000. The charge retention time can maintain over 100 000 s. Similar memory behaviors are also observed in other common semiconducting polymers such as poly(3-hexyl thiophene) and poly[2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene], and a high mobility donor-acceptor polymer, poly(isoindigo-bithiophene). In summary, these observations suggest that this approach is a general method to induce memory behavior in conjugated polymers. To the best of the knowledge, this is the first report for p-type polymer memory achieved using n-type charge-transfer doping.

Keywords: field-effect transistors; n-type doping; nonvolatile memory.