APPLIED PHYSICS LETTERS (2013)
Supplemental Material
Solution-processed high-performance flexible 9, 10-bis(phenylethynyl)anthracene
organic single-crystal transistor and ring oscillator
Xiaozhou Cai,1,2 Deyang Ji,2 Lang Jiang,2 Guangyao Zhao,2 Jiahui Tan2 , Guofeng Tian3 ,
Jingze Li1,a) and Wenping Hu2,b)
1
State Key Laboratory of Electronic Thin Films and Integrated Devices, School of
Microelectronics and Solid-State Electronics, University of Electronic Science and Technology of
China, Chengdu 610054, China
2
Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids,
Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
3
China Beijing University of Chemical Technology, Beijing 100029 ,China
FIG. S1 Typical micrographs of the BPEA single crystal ribbons, where the length is generally
around few hundreds of micrometers, and even possible approaches to millimeter scale.
FIG. S2 Typical micrographs of the BPEA single crystal ribbon on the different stage of seed induced
growth. (a) The preset BPEA seed crystal; The growth period was extended for (b) 48 hours and
(c) 72 hours, confirming the growth of the BPEA single crystal ribbon really starts from one end
of the seed crystal.
APPLIED PHYSICS LETTERS (2013)
FIG. S3 Typical micrographs of the BPEA single crystal ribbons with (a) two or (b) three seed
crystals prepositioned in the parallel way. As a result, the obtained BPEA ribbons are parallel
3.0
2
Mobility / cm /vs
aligned, indicating the seed crystal can really guide the growth direction of the ribbon.
2.5
2.0
1.5
1.0
500
600
700
800
900
1000
Ribbon Width / nm
FIG. S4 The field-effect mobility of the BPEA single crystal ribbon transistor as a function of the
ribbon width for 51 transistors, where the source and drain Au electrodes was treated with
thiophenol.
APPLIED PHYSICS LETTERS (2013)
FIG. S5 The photograph image of the electrical test setup for characterizing BPEA single crystal
transistor on PI flexible substrate.
FIG. S6 (a) The schematic structure of the inverter based on individual BPEA single crystal ribbon;
(b) The corresponding micrograph image of the BPEA single crystal inverter.
APPLIED PHYSICS LETTERS (2013)
The procedure how to deduce the carrier mobility:
Since organic field effect transistor (OFET) and inorganic field effect transistor (IFET) share
similar working mechanism, it is possible to estimate the electric parameters of OFET by using
the well established method for IFET. While the device is working in saturation regime, the
relationship among the current IDS and the voltages can be expressed as following.[1]
(1)
Where IDS is the current between the drain and source, W/L is the ratio of the width to the
length for each transistor,  is the intrinsic mobility in the channel region, Ci is the insulator
capacitance per unit area, VG is the gate voltage, and Vth is the threshold voltage.
Since the transistor is working in the saturation regime, the current is very stable, which is
aided for the precise calculation of the carrier mobility. Thus, the saturation regime of the transfer
characteristics was applied to estimate the carrier mobility.
The mobility can be easily deduced by changing the form of the equation (1) as
(2)
While ISD1/2 is plotted as a function of VG according to the equation (2), the slop of a line
tangent to the curve, i.e.,
, can generate the field effect mobility μ. Below is the
corresponding equation.
[1] S. M. Sze. Semiconductor Devices: Physics and Technology. Wiley, New York, 1985.