只用于动物实验研究等 DatasheetThe highest regioregularity P3HT (M104, RR = 96.3%) produces highly crystalline films and is recommended for OFETs, nanofibril formation and fast drying OPVs at the thin interference peak (90 nm). However, the exceptionally high regioregularity of this P3HT means that gelling and surface roughness can be an issue for slow-drying thick-film OPVs (>200 nm). Lower molecular weight and regioregularity P3HT is recommended for inkjet and other large area or slow drying deposition techniques where gelling/aggregation and surface roughness need to be avoided. A fabrication report with mobility measurements of 0.12 cm2/Vs for M104 can be found below. All the P3HT below is highly soluble (50 mg/ml) in chlorinated solvents such as chloroform, chlorobenzene, dichlorobenzene and trichlorobenzene. The intermediate and lower molecular weight P3HT materials are recommended for use with non-chlorinated solvents such as xylene, toluene and THF due to their increased solubility. CAS number: 104934-50-1 Usage DetailsMobility Measurements for M104 - Fabrication RoutineA full fabrication report can be downloaded here. Field effect mobilities in excess of 0.12 cm2/Vs are recorded using M104 when the active layer is dispensed on OTS-treated silicon oxide dielectric by static spin coating from an optimized high/low boiling point solvent mix. High hole mobility in conjunction with good solubility and partial air stability make regioregular P3HT a reference material of choice for both fundamental and applied research in organic electronic, physics and chemistry. As one of the most well-studied organic semiconductor, P3HT is often acknowledge to be one of the benchmark against which any new p-type or donor conjugate molecule should be compared and evaluated. Mobility has previously been found to be positively correlated with increasing region-regularity, slow drying time (achieved using high boiling point solvent), lowering of the surface energy, and molecular weight in excess of 50 kD. These conditions favour p-p stacking parallels to the OFET substrate, which in turn results in improved charge transport across the transistor channel [1-13]. Substrate size | 20 x 15 mm | Gate conductivity | 1-30 O·cm (Boron doped) | Silicon oxide thickness | 300 nm | Device per substrates | Five, common gate | Channel length | 30 µm | Channel width | 1000 µm |
The active layer solution preparation, spin coating, substrate annealing and measurements are performed in a glove box under a nitrogen atmosphere (H2O <0.1 PPM; O2 < 5/8 PPM). For generic details on the fabrication of OPV devices, please see our written guide and video demonstration. Active Layer Preparation High-Regioregular and high molecular weight RR-P3HT (M104) (RR = 96.3%, Mw = 77,500, Mn = 38,700) is dissolved in a mix of high and low boiling point solvent in order to exploit the beneficial effect of long drying time and increase the wettability of low energy surface, respectively. - 5 mg/ml of M104 dissolved in anhydrous Chloroform:Trichlorobenzene (99:1) mix;
- Vial is placed on hot plate (70°C) with a stirrer bar for 30 minutes;
- Solution cooled down at room temperature and then filtered with a 0.45 µm PTFE filter;
- Solution stored overnight on a hot plate at 30°C to prevent excessive aggregation of the P3HT molecules.
Substrate Cleaning - Substrates loaded on to substrate rack (to keep them in upright position);
- Sonicated in hot Hellmanex solution (1%) for five minutes;
- Rinsed twice in hot water;
- Sonicated in warm Isopropyl alcohol (70°C) for five minutes;
- Rinsed twice in cold DI water;
- Substrates stored in DI water.
Thermal Deposition of Electrodes and Contact Pads - Done on Edwards 306 Thermal coater in clean room condition;
- Substrates are blown dry and loaded in a low density evaporation stack with a low density shadow mask to pattern the desired features;
- Secondary mask is added to selectively evaporate the gate and drain/source pads;
- Vacuum chamber pumped down to a vacuum pressure of 5 x 10-6 mbar;
- Chromium adhesion layer: 5 nm, rate 0.05 nm/s;
- Aluminium: 80 nm, rate: 0.4 nm/s;
- Changed secondary mask to deposit electrodes (FET channels);
- Vacuum: 2-3 x 10-6 mbar;
- Chromium adhesion layer: 1 nm, rate 0.05 nm/s;
- Gold: 40 nm; rate 0.05 nm/s.
PFBT Treatment for Au Electrodes (Laminar flow) - Oxygen plasma treatment, 30 seconds at 100 W;
- Substrates immersed in 2.5 mMol/l solution of PFBT in isopropyl alcohol at room temperature;
- Substrates rinsed twice in pure isopropyl alcohol;
- Substrates are blown with nitrogen gun.
OTS Treatment for SiO2 Dielectric (Laminar flow) - 200 µl solution of pure OTS in cyclohexane, anhydrous grade, prepared in glove box so to obtain a final concentration of 1 mMol/l;
- Trough filled with 60 ml of cyclohexane, HPLC grade, in laminar flow;
- Previously prepared OTS solution quickly added to the cyclohexane and mixed with a pipette tip;
- Substrate (pre-loaded on a substrate rack) immersed in the trough;
- Trough topped up with extra 3 ml cyclohexane and closed with a glass lid. The final solution (63 ml) contain OTS at a concentration of 1 mMol/l;
- Substrates kept for 18 minutes in the OTS solution;
- Substrates removed from the OTS solution, quickly rinsed twice in clean Cyclohexane, and then are blown dry with nitrogen gun.
Contact Angle Assessment The water-drop test on the treated silicon is a quick test to qualitatively assess the effect of the OTS on the silicon substrates, see Fig. 3. Note that quantitative assessment has previously shown this routine to produce contact angles of 110°C and this test is used as a quick reference to ensure fabrication has functioned correctly. P3HT (M104) spin coating (glove box) - 30 µl of Organic Semi-Conductor (OSC) solution delivered on the middle of the substrate and then spin coated at 1000 rpm for 10 s followed by 60 s at 2000 rpm;
- Cotton swab soaked in chlorobenzene to thoroughly wipe clean the contact pads and the rest of the substrates with the exception of the area around the channel;
- High precision cotton swab to clean between devices to avoid cross-talking and reduce leakage;
- Substrates annealed at 90°C for 30 minutes;
- Cooled down for ten minutes;
- Five devices per substrate automatically characterised using Ossila FACT1 in glove box, see Fig 4;
- Second annealing at 120°C for 20 minutes, slow cooling down at room temperature and measurement;
- Annealing at 150°C for 20 minutes, slow cooling down at room temperature and measurement.
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