TY - JOUR
T1 - Polymer interfacial layer with high glass transition temperature for the improvement of bias stability in organic field-effect transistors
AU - Roh, Jeongkyun
AU - Shin, Hyeonwoo
AU - Kim, Hyeok
AU - Lee, Changhee
N1 - Publisher Copyright:
Copyright © 2016 American Scientific Publishers All rights reserved.
PY - 2016/10
Y1 - 2016/10
N2 - We investigated the bias stability of organic field-effect transistors (OFETs) with a gate dielectric modified with a polymer with a high glass transition temperature, which is a cyclic olefin copolymer (COC). With the COC modification, the surface of the SiO2 gate dielectric became significantly more hydrophobic and exhibited low surface energy, which yielded an enhanced crystallinity of the organic semiconductors. As a result of a reduced surface trap density and enlarged grain size that was obtained by employing COC, the bias stability and electrical performance of a pentacene OFET were remarkably improved. After two hours of biasing, the bias-stress-induced threshold voltage shift (ΔVTH) was significantly reduced from 10 V to 2 V, and the relaxation time (π) extracted from a stretched exponential fit was extended from 2.7 × 104 sec to 4.7 × 106 sec. We also applied this surface modification method to n-type OFETs and determined that the COC modification is applicable to other types of FETs to improve the bias stability.
AB - We investigated the bias stability of organic field-effect transistors (OFETs) with a gate dielectric modified with a polymer with a high glass transition temperature, which is a cyclic olefin copolymer (COC). With the COC modification, the surface of the SiO2 gate dielectric became significantly more hydrophobic and exhibited low surface energy, which yielded an enhanced crystallinity of the organic semiconductors. As a result of a reduced surface trap density and enlarged grain size that was obtained by employing COC, the bias stability and electrical performance of a pentacene OFET were remarkably improved. After two hours of biasing, the bias-stress-induced threshold voltage shift (ΔVTH) was significantly reduced from 10 V to 2 V, and the relaxation time (π) extracted from a stretched exponential fit was extended from 2.7 × 104 sec to 4.7 × 106 sec. We also applied this surface modification method to n-type OFETs and determined that the COC modification is applicable to other types of FETs to improve the bias stability.
KW - Bias stability
KW - High glass transition temperature polymer
KW - Organic field-effect transistors
UR - http://www.scopus.com/inward/record.url?scp=84991070144&partnerID=8YFLogxK
U2 - 10.1166/jnn.2016.13153
DO - 10.1166/jnn.2016.13153
M3 - Article
AN - SCOPUS:84991070144
SN - 1533-4880
VL - 16
SP - 10325
EP - 10330
JO - Journal of Nanoscience and Nanotechnology
JF - Journal of Nanoscience and Nanotechnology
IS - 10
ER -