Determination of Interface-State Distributions in Polymer-Based Metal-Insulator-Semiconductor Capacitors by Impedance Spectroscopy

Abstract

Information on localized states at the interfaces of solution-processed organic semiconductors and polymer gate insulators is critical to the development of printable organic field-effect transistors (OFETs) with good electrical performance. This paper reports on the use of impedance spectroscopy to determine the energy distribution of the density of interface states in organic metal-insulator-semiconductor (MIS) capacitors based on poly(3-hexylthiophene) (P3HT) with three different polymer gate insulators, including polyimide, poly(4-vinylphenol), and poly(methylsilsesquioxane). The findings of the study indicate that the impedance characteristics of the P3HT MIS capacitors are strongly affected by patterning and thermal annealing of the organic semiconductor films. To extract the interface-state distributions from the conductance of the P3HT MIS capacitors, an equivalent circuit model with continuum trap states is used, which also takes the band-bending fluctuations into consideration. In addition, the relationship between the determined interface states and the electrical characteristics of P3HT-based OFETs is investigated.

Energy distribution of interface states generated by oxygen plasma treatment for control of threshold voltage in pentacene thin-film transistors

“…The (D M + D H ) monotonically decreases on average with an increase in qΨ S . The values of (D M + D H ) are comparable to those of MOS capacitors having crystal Si [35], amorphous Si [36], SiC [56], GaN [57], and polymers [58,59] as a semiconductor. When integrating (D M + D H ) with respect to qΨ S , the area densities are obtained as 4.9, 6.2, and 9.7 × 10 11 cm −2 for t P = 10, 20, and 30 s, respectively.…”

A Sub‐20 nm Organic/Inorganic Hybrid Dielectric for Ultralow‐Power Organic Thin‐Film Transistor (OTFT) With Enhanced Operational Stability

“…For further in-depth analysis on the dielectric/organic semiconductor interfaces, we assessed the interface trap density (D it ) by a conductance method, which has been used widely for the trap density analysis in Si-based electronics. [65] As the equivalent circuit models of organic metal-insulator-semiconductor (MIS) capacitors are similar to those of Si-based metal-oxide semiconductor (MOS) capacitors, [66,67] D it analysis via a conductance method has been utilized broadly for the organic devices as well. [53,[68][69][70] We monitored the D it variation according to the frequency in the subthreshold region (V G from −1 to −2 V) by using the MIS stack (Figure S5, Supporting Information) and the maximum D it (D it,max ) value was extracted for each V G (Figure 2h).…”

The Potential Barrier and Thermal Stability Dependence on PI Thickness of Al/PI/c-Si Schottky Diode

“…12, pp: 3235-3241 2323 It was observed that the decomposition temperature (T 5 , T 10 and T g ) of the PI was increased by about 38, 35 and 40 ο C, respectively, when the thickness of PI film was increased. This behavior is due to the increase of the number of imide bonds and the decrease of average distance between imide groups which enhances the intermolecular interaction [14,15].…”