A Simple and Direct Method for Interface Characterization of OFETs
11 Jul 2007-pp 306-309
TL;DR: In this article, the multi-frequency transconductance technique is successfully applied in this work for the first time for interface characterization of OFETs, and the results show interface state densities in the range of 1012/cm2/eV for both the samples.
Abstract: Multi-frequency transconductance technique is successfully applied in this work for the first time for interface characterization of OFETs. Standard charge pumping measurements are used on silicon MOSFETs for the validation of MFT technique. The method is implemented on pentacene as well as the P3HT based OFETs with SiO2 as the gate dielectric. Our results show interface state densities in the range of 1012/cm2/eV for both the samples. The P3HT films are also shown to have additional trap centres which respond to frequencies above 100 kHz. Our results therefore clearly indicate that the MFT technique is indeed a highly useful technique for interface characterization of OFETs.
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TL;DR: An all-polymer semiconductor integrated device is demonstrated with a high-mobility conjugated polymer field-effect transistor driving a polymer light-emitting diode (LED) of similar size, which represents a step toward all- polymer optoelectronic integrated circuits such as active-matrix polymer LED displays.
Abstract: An all-polymer semiconductor integrated device is demonstrated with a high-mobility conjugated polymer field-effect transistor (FET) driving a polymer light-emitting diode (LED) of similar size. The FET uses regioregular poly(hexylthiophene). Its performance approaches that of inorganic amorphous silicon FETs, with field-effect mobilities of 0.05 to 0.1 square centimeters per volt second and ON-OFF current ratios of >10 6 . The high mobility is attributed to the formation of extended polaron states as a result of local self-organization, in contrast to the variable-range hopping of self-localized polarons found in more disordered polymers. The FET-LED device represents a step toward all-polymer optoelectronic integrated circuits such as active-matrix polymer LED displays.
2,657 citations
"A Simple and Direct Method for Inte..." refers methods in this paper
...Use of HMDS in the P3HT based OFETs has also been E shown to improve the performance of solution processed 0 OFETs [9]....
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TL;DR: In this article, an electrophoretic ink based on the microencapsulation of an electrophic dispersion was used to solve the lifetime issues and allow the fabrication of a bistable electronic display solely by means of printing.
Abstract: It has for many years been an ambition of researchers in display media to create a flexible low-cost system that is the electronic analogue of paper. In this context, microparticle-based displays1,2,3,4,5 have long intrigued researchers. Switchable contrast in such displays is achieved by the electromigration of highly scattering or absorbing microparticles (in the size range 0.1–5 μm), quite distinct from the molecular-scale properties that govern the behaviour of the more familiar liquid-crystal displays6. Microparticle-based displays possess intrinsic bistability, exhibit extremely low power d.c. field addressing and have demonstrated high contrast and reflectivity. These features, combined with a near-lambertian viewing characteristic, result in an ‘ink on paper’ look7. But such displays have to date suffered from short lifetimes and difficulty in manufacture. Here we report the synthesis of an electrophoretic ink based on the microencapsulation of an electrophoretic dispersion8. The use of a microencapsulated electrophoretic medium solves the lifetime issues and permits the fabrication of a bistable electronic display solely by means of printing. This system may satisfy the practical requirements of electronic paper.
1,210 citations
TL;DR: Pentacene-based organic thin-film transistors (TFT's) with field effect mobility as large as 0.7 cm/sup 2/V/spl middot/s and on/off current ratio larger than 10/sup 8/ have been fabricated as mentioned in this paper.
Abstract: Pentacene-based organic thin-film transistors (TFT's) with field-effect mobility as large as 0.7 cm/sup 2//V/spl middot/s and on/off current ratio larger than 10/sup 8/ have been fabricated. Pentacene films deposited by evaporation at elevated temperature at low-to-moderate deposition rates have a high degree of molecular ordering with micrometer-sized and larger dendritic grains. Such films yield TFT's with large mobility. Films deposited at low temperature or by flash evaporation have small grains and poor molecular ordering and yield TFT's with low mobility.
754 citations
"A Simple and Direct Method for Inte..." refers background in this paper
...* CP * MFT Aspentacene isthermally evaporated, itisexpected tohave abetter interface withtheSiO2layer compared tothat of > 5.0 P3HT.Thisisbecause ofthebetter molecular ordering a) obtained duetotheprocess usedfordepositing thepolymer [ 8 ]....
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TL;DR: The first organic complementary circuits on flexible substrates were reported in this article using pentacene and hexadecafluorocopperphthalocyanine (F/sub 16/CuPc) semiconductors.
Abstract: We report the first organic complementary circuits on flexible substrates. Organic thin-film transistors were fabricated using pentacene as the semiconductor for the p-channel devices and hexadecafluorocopperphthalocyanine (F/sub 16/CuPc) as the semiconductor for the n-channel devices. Both semiconductors were purchased from commercial sources and deposited by evaporation in vacuum. The pentacene layer was photolithographically patterned to simplify the circuit layout and reduce the circuit area. The transistors and circuits were manufactured on thin, transparent sheets of polyethylene naphthalate. Evaporated metals were used to define all contacts and interconnects, and a 50-nm-thick layer of solution-processed polyvinylphenol was used as the gate dielectric. Transistors and circuits operate at supply voltages as low as 8 V, and ring oscillators have a signal propagation delay as low as 8 /spl mu/s per stage. To our knowledge, these are the fastest organic complementary circuits reported to date.
167 citations
"A Simple and Direct Method for Inte..." refers background or methods in this paper
...Thusbyvarying the inthecalculated D1tvalues hasbeenobtained withthetwo frequency ofsmall signal gatevoltage fromasuitably low methods (Fig. 2).Thevariation oftheTransconductance value(where allthetraps respond) toasufficiently high withfrequency forthestressed device isalso shown(Fig. 3 ). value (where notraps respond), onecanestimate thevalue ofD,tTheinterface state density iscalculated fromthe Theexperiments onMOSFETswerefollowed bythe ......
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...frequency identification tags[2, 3 ].ForOrganic Field Effect Transistors (OFETs), bothCPandTCParenotapplicable as these transistors lack abodycontact andapplication ofhigh...
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...Polymer (both inpm) (nm) contacts 0 3 .37 9.2 Pentacene 500/150 200 Top...
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...IC r 1A 1 (1) gatedielectric. The secondsamplehas Poly-( 3 -...
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TL;DR: In this paper, the authors proposed a new method to determine the interface trap density in partially depleted silicon-on-insulator (SOI) floating body MOSFETs.
Abstract: A new method to determine the interface trap density in partially depleted silicon-on-insulator (SOI) floating body MOSFETs is proposed for the first time. It can be considered as a "transient" charge-pumping (CP) technique in contrast to the normally used "steady-state" method. In our technique, majority carriers are removed from the floating body by applying a burst of pulses to the transistor gate. The change in the linear drain current after each pulse is used to determine the device interface trap density. The unique advantage of this method is the possibility to use it to characterize SOI MOSFETs without a body contact. The technique proposed is simple, reliable, and can be used for the characterization of deep submicron devices.
108 citations
"A Simple and Direct Method for Inte..." refers background in this paper
...The FETs suggested as an alternative to these devices [1]....
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