A novel investigation on a relationship between temperature-influential self-assembly (70-300 degrees C) of 4-pentynoic acid functionalized Fe3O4-gamma-Fe2O3 nanoparticles (NPs) on SiO2/n-Si with electrical properties was reported with the interests for metal-oxide-semiconductor applications. X-ray diffractometer (XRD) analysis conveyed that 8 +/- 1 nm of the NPs were assembled. Increasing heating temperature induced growth of native oxide (SiO2). Raman analysis confirmed the coexistence of Fe3O4-gamma-Fe2O3. Attenuated Total Reflectance Infrared (ATR-IR) spectra showed that self-assembly occurred via Si-O-C linkages. While Si-O-C linkages were broken down at elevated temperatures, formations of Si-OH defects were amplified; a consequence of physisorbed surfactants disintegration. Atomic force microscopy (AFM) showed that sample with more physisorbed surfactants exhibited the highest root-mean-square (RMS) roughness (18.12 +/- 7.13 nm) whereas sample with lesser physisorbed surfactants displayed otherwise (12.99 +/- 4.39 nm RMS roughness). Field Emission Scanning Electron Microscope (FE-SEM) analysis showed non-uniform aggregation of the NPs, deposited as film (12.6 mu m thickness). The increased saturation magnetization (71.527 A m(2)/kg) and coercivity (929.942 A/m) acquired by vibrating sample magnetometer (VSM) of the sample heated at 300 degrees C verified the surfactants' disintegration. Leakage current density-electric field (J-E) characteristics showed that sample heated at 150 degrees C with the most aggregated NPs as well as the most developed Si-O-C linkages demonstrated the highest breakdown field and barrier height at 2.58 x 10(-3) MV/cm and 0.38 eV respectively. Whereas sample heated at 300 degrees C with the least Si-O-C linkages as well as lesser aggregated NPs showed the lowest breakdown field and barrier height at 1.08 x 10(-3) MV/cm and 0.19 eV respectively. This study opens up better understandings on how formation and breaking down of covalent linkages as well as accumulation of defects, particularly prior temperature influential self-assembly at the interfaces, affected electrical breakdown field and barrier height. Hence, possible future development of self-assembly silicon-based metal-oxide-semiconductor (MOS) structure particularly in the presence of SiO2 can be deliberated. (C) 2017 Elsevier B.V. All rights reserved.