4.1.6. Preparation of Bis(3,4,5-trifluorophenoxy) Silicon Phthalocyanine

Reaction was performed analogous to previously reported literature using as prepared SiPcCl2 from Routes A–C. Samples were characterized spectroscopically and compared to references in literature [29]. HR-MS (EI) for C38H18N8OF3Si [M–C6H2OF3] <sup>+</sup>: Calcd, 687.1325; Found (Route A), 687.1311; Found (Route B), 687.1330; Found (Route C), 687.1315.

#### 4.1.7. Electrical Testing

Bottom-gate, bottom-contact OTFTs made with (345F)2-SiPc active layers were made starting with prefabricated substrates manufactured by Fraunhofer IPMS. These substrates had a doped silicon base/gate, a 230 nm SiO2 dielectric, and pre-patterned source-drain electrodes made from gold with an indium tin oxide adhesion layer (W = 2000 μm, L = 2.5, 5, 10, 20 μm). Substrates were rinsed thoroughly with acetone to remove the protective resist and then treated for 15 min in oxygen plasma. Before transferring into a 1% v/v solution of octyltrichlorosilane (OTS, Sigma, 97%) in toluene, the substrates were rinsed with water and isopropanol, then dried with nitrogen. After 60 min heating at 70 ◦C, the substrates were removed from solution, rinsed with toluene and isopropanol, then dried under vacuum at 70 ◦C for 30–60 min. Dried, OTS-treated substrates were transferred into a vacuum chamber where (345F)2-SiPc was evaporated onto their surface at a rate of 0.3Å/s until their thickness reached the target of 300Å as measured using a quartz crystal monitor. Finished devices were transferred in an evacuated capsule to the custom OTFT testing setup, oesProbe A10000-P290 (Element Instrumentation Inc. & Kreus Design Inc.), and tested under vacuum (P < 0.1 Pa) without having been exposed to air. Transfer characteristics were obtained in the range 0 V < VGS < 60 V, increased step-wise every 100 ms, with VDS set to 50 V. Field-effect mobility (μe) and threshold voltage (VT) were calculated from the slope and x-intercept of Equation (1) in the range 35 V < VGS < 45 V, with the dielectric capacitance

Ci calculated as kε0/t, where t is the dielectric thickness and k is the relative dielectric constant of SiO2 (3.9).

$$\mathbf{I}\_{\rm DS} = \frac{\mu \mathbf{C}\_{\rm i} \mathbf{W}}{2\mathbf{L}} (\mathbf{V}\_{\rm GS} - \mathbf{V}\_{\rm T}) \tag{1}$$

**Supplementary Materials:** The following are available online at http://www.mdpi.com/1996-1944/12/8/1334/s1, Figure S1: Normalized absorbance spectra of (345F)2-SiPc via Routes A (black), B (blue) and C (red) in toluene solutions, Figure S2: 1H-NMR spectra of DIII from Route B at 400 MHz in MeCN-d3. Spectrum referenced to solvent residual peak at 1.94 ppm, Figure S3: 1H-NMR spectra of [H2DIII][OTf]2 at 300 MHz in MeCN-d3. Spectrum referenced to solvent residual peak at 1.94 ppm, Figure S4: 1H-NMR spectra of DIII from commercial source (blue) and from Route B (red) in DMSO-d6 at 400 MHz. Spectra referenced to residual solvent peak at 2.50 ppm, Figure S5. 19F-NMR spectra of [H2DIII][OTf]2 at 300 MHz in MeCN-d3. Spectrum referenced to F3CCOH at −76.55 ppm.

**Author Contributions:** All authors contributed equally to this work.

**Funding:** The authors thank the University of Ottawa, the Canadian Foundation for Innovation (CFI), NSERC (Discovery grants and PGSD programs) and the Ontario Research Fund. N.J.Y. thanks NSERC for the Canada Graduate Scholarship (CGS D), O.A.M and T.M.G. are also grateful for the Ontario graduate student scholarship (OGS).

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**


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