# Electro-Optic Properties of High-Efficiency Organic Electronics with the Addition of An Interlayer
## 3 Results and Discussion  
The hydrolysis reaction starts when a film of SAM is deposited on the surface of ITO, and it is formed by the impact of Van Der Waals force. The SAM thin film deposition process on ITO varies depending on the deposition method. The dipping method might require ranging from a few minutes to many days to deposit SAM [16]. The formation of SAM on the ITO surface involves the following steps: 1. The precleaned ITO is added to a solution containing SAM. The dissolved SAMs are deposited on the surface of the ITO through chemisorption. 2. The C\({}_{2}\)H\({}_{5}\)O radical of the SAM head group is replaced by the OH group under the influence of the hydrolysis process, resulting in the release of ethanol. 3. The precleaned ITO-coated glass is added to the hybrid solution. The dissolved perfluoroalkylesilanes are deposited on the surface of the ITO through chemisorption. The process of formation of monolayers has the unique feature of self-ordering due to Van der Waals forces [33]. Figure 2 shows the graph of surface energy and contact angle. Vapor deposition was used to identify the surface properties of SAMs according to the filming time. A PFA container with the hybrid solution was placed in a convection oven at 120 \({}^{\circ}\)C for 60 min. The result confirmed that the coating of the hydrophobic SAM film was adequate, as the hydrophobicity of the surface gradually increased. The surface initially showed a level of hydrophilicity similar to that of the basic ITO due to the low level of SAM filming of 48.68\({}^{\circ}\) at 1 min; however, over time, the level increased to 67.43\({}^{\circ}\) at 10 min, 71.78\({}^{\circ}\) at 30 min, and 81.26\({}^{\circ}\) at 60 min. When the surface energy was calculated using the Girifalco-Good-Fowkes-Young method with DI water as the reference solution, the ITO surface energy with SAM filming was found to decrease by as much as 50% from 61.93 (mN/m) at 1 min to 43.02 (mN/m) at 10 min, 38.71 (mN/m) at 30 min, and 29.81 (mN/m) at 60 min, while an inverse correlation was observed between surface energy and contact angle. This result indicated that, with the hybrid solution, the contact angle steadily increased in line with the filming time, and the longer the filming time, the higher the gradual hydrophobicity acquired by the ITO substrate. Finally, compared to the ITO substrate with its initial hydrophilicity, the film coating was found to be adequate. The surface energy can be improved by reducing the concentration of the hydroxyl groups on the ITO surface, which prevents the isolation of the hole transport layer from the ITO [21,35]. The addition of the hole injection and hole transport layers to the opto-electronic device may have improved the stability, thereby enhancing the applications potential [36]. When the surface of the substrate on which the SAM single molecular film is formed is confirmed, the effect is relatively low compared to the average surface roughness of the existing ITO [37]. The interfacial interaction between the layers can be improved by improving the surface roughness [38]. With an uneven surface, the interfacial interaction between the layers is frequently weak all through deposition [39]. Figure 3 shows the characteristics of voltage and current density curves. As can be seen, the current density of the device with the injection of the hybrid solution at the HIL (Device (A)) is 3.2691 (mA/cm\({}^{2}\)) from 4 V, showing a steady increase compared to Device (B) or (C) without the HIL and HTL interlayer. Device (B) without HIL reached a current density of 4.0121 (mA/cm\({}^{2}\)), close to that of Device (A) at 6 V. Device (C) without either HIL or HTL reached the current density of 3.7802 (mA/cm\({}^{2}\)) close to that of Device (A) at