PMID- 26804625
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20160627
LR  - 20160217
IS  - 1944-8252 (Electronic)
IS  - 1944-8244 (Linking)
VI  - 8
IP  - 6
DP  - 2016 Feb 17
TI  - Effect of Polymer Binders on UV-Responsive Organic Thin-Film Phototransistors 
      with Benzothienobenzothiophene Semiconductor.
PG  - 3744-54
LID - 10.1021/acsami.5b09001 [doi]
AB  - The influence of polymer binders on the UV response of organic thin-film 
      phototransistors (OTF-PTs) is reported. The active channel of the OTF-PTs was 
      fabricated by blending a UV responsive 
      2,7-dipenty-[1]benzothieno[2,3-b][1]benzothiophene (C5-BTBT) as small molecule 
      semiconductor and a branched unsaturated polyester (B-upe) as dielectric binder 
      (ratio 1:1). To understand the influence of the polymer composition on the 
      photoelectrical properties and UV response of C5-BTBT, control blends were 
      prepared using common dielectric polymers, namely, poly(vinyl acetate) (PVAc), 
      polycarbonate (PC), and polystyrene (PS), for comparison. Thin-film morphology 
      and nanostructure of the C5-BTBT/polymer blends were investigated by means of 
      optical and atomic force microscopy, and powder X-ray diffraction, respectively. 
      Electrical and photoelectrical characteristics of the studied OTF-PTs were 
      evaluated in the dark and under UV illumination with a constant light intensity 
      (P = 3 mW cm(-2), lambda = 365 nm), respectively, using two- and three-terminal I-V 
      measurements. Results revealed that the purposely chosen B-upe polymer binder 
      strongly affected the UV response of OTF-PTs. A photocurrent increase of more 
      than 5 orders of magnitude in the subthreshold region was observed with a 
      responsivity as high as 9.7 AW(-1), at VG = 0 V. The photocurrent increase and 
      dramatic shift of VTh,average ( approximately 86 V) were justified by the high number of 
      photogenerated charge carriers upon the high trap density in bulk 8.0 x 10(12) 
      cm(-2) eV(-1) generated by highly dispersed C5-BTBT in B-upe binder. Compared 
      with other devices, the B-upe OTF-PTs had the fastest UV response times (taur1/taur2 
      = 0.5/6.0) reaching the highest saturated photocurrent (>10(6)), at VG = -5 V and 
      VSD = -60 V. The enhanced UV sensing properties of B-upe based OTF-PTs were 
      attributed to a self-induced thin-film morphology. The enlarged interface 
      facilitated the electron withdrawing/donating functional groups in the polymer 
      chains in influencing the photocharge separation, trapping and recombination.
FAU - Ljubic, Darko
AU  - Ljubic D
AD  - Xerox Research Centre of Canada , 2660 Speakman Drive, Mississauga, Ontario L5K 
      2L1, Canada.
AD  - Department of Chemical Engineering, McMaster University , Hamilton, Ontario LS8 
      4L8, Canada.
FAU - Smithson, Chad S
AU  - Smithson CS
AD  - Xerox Research Centre of Canada , 2660 Speakman Drive, Mississauga, Ontario L5K 
      2L1, Canada.
AD  - Department of Chemical Engineering, McMaster University , Hamilton, Ontario LS8 
      4L8, Canada.
FAU - Wu, Yiliang
AU  - Wu Y
AD  - Xerox Research Centre of Canada , 2660 Speakman Drive, Mississauga, Ontario L5K 
      2L1, Canada.
FAU - Zhu, Shiping
AU  - Zhu S
AD  - Department of Chemical Engineering, McMaster University , Hamilton, Ontario LS8 
      4L8, Canada.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20160205
PL  - United States
TA  - ACS Appl Mater Interfaces
JT  - ACS applied materials & interfaces
JID - 101504991
OTO - NOTNLM
OT  - UV responsive
OT  - benzothiophene
OT  - organic thin-film phototransistors
OT  - photoresponsivity
OT  - semiconductor blends
EDAT- 2016/01/26 06:00
MHDA- 2016/01/26 06:01
CRDT- 2016/01/26 06:00
PHST- 2016/01/26 06:00 [entrez]
PHST- 2016/01/26 06:00 [pubmed]
PHST- 2016/01/26 06:01 [medline]
AID - 10.1021/acsami.5b09001 [doi]
PST - ppublish
SO  - ACS Appl Mater Interfaces. 2016 Feb 17;8(6):3744-54. doi: 10.1021/acsami.5b09001. 
      Epub 2016 Feb 5.