Disclosed herein are NPN-type low molecular aromatic ring compounds, organic semiconductor layers formed from such compounds that exhibit improved electrical stability and methods of forming such layers using solution-based processes, for example, spin coating processes performed at or near room temperature. These NPN-type compounds may be used, either singly or in combination, for fabricating organic semiconductor layers in electronic devices. The NPN-type aromatic ring compounds according to example embodiments may be deposited as a solution on a range of substrates to form a coating film that is then subjected to a thermal treatment to form a semiconductor thin film across large substrate surfaces that exhibits reduced leakage currents relative to conventional PNP-type organic semiconductor materials, thus improving the electrical properties of the resulting devices.