Portal de Periódicos da CAPES

Fully Current-Based Sub-Bandgap Optoelectronic Differential Ideality Factor Technique and Extraction of Subgap DOS in Amorphous Semiconductor TFTs

2014; Institute of Electrical and Electronics Engineers; Volume: 61; Issue: 10 Linguagem: Inglês

10.1109/ted.2014.2348592

1557-9646

Hagyoul Bae, Hyojoon Seo, Sungwoo Jun, Hyun‐Jun Choi, Jaeyeop Ahn, Jun-Seok Hwang, Jungmin Lee, Saeroonter Oh, Jong Uk Bae, Sung‐Jin Choi, Dae Hwan Kim, Dong Myong Kim,

Semiconductor materials and devices

A sub-bandgap optoelectronic differential ideality factor technique is proposed for extraction of the intrinsic density-of-states (DOS) over the bandgap in amorphous semiconductor thin-film transistors (TFTs). In the proposed technique, the gate bias-dependent differential change in the difference of ideality factors ( $d\Delta \eta (V_{\mathrm {GS}})/dV_{\mathrm {GS}}$ ) between dark and sub-bandgap photonic excitation condition is employed. With the sub-bandgap photons ( $h\nu < E_{g}$ ), the photonic excitation of electrons is confined only from the localized DOS over the bandgap. We applied the proposed technique to a-InGaZnO TFTs with $W/L = 50/25 \mu $ m/ $\mu $ m and extracted the energy distribution of the intrinsic DOS for the localized states over the bandgap.