Single-Scan Monochromatic Photonic Capacitance-Voltage Technique for Extraction of Subgap DOS Over the Bandgap in Amorphous Semiconductor TFTs

• Published in: IEEE electron device letters Vol. 34; no. 12; pp. 1524 - 1526
• Main Authors: Hagyoul Bae, Hyunjun Choi, Sungwoo Jun, Chunhyung Jo, Yun Hyeok Kim, Jun Seok Hwang, Jaeyeop Ahn, Oh, Saeroonter, Jong-Uk Bae, Sung-Jin Choi, Dae Hwan Kim, Dong Myong Kim
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01-12-2013; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Acceptor-like states; amorphous; Applied sciences; Capacitance; Circuit properties; density of states (DOS); donor-like states; Electric, optical and optoelectronic circuits; Electronics; Exact sciences and technology; extraction; Indium gallium zinc oxide; Integrated circuit modeling; Integrated optics. Optical fibers and wave guides; Optical and optoelectronic circuits; Photonic band gap; photonic capacitance; Photonics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Thin film transistors; thin-film transistors (TFT); Transistors; Integrated optics; Amorphous material; Density of states; amorphous; donor-like states; Amorphous semiconductors; Gallium oxide; n channel; Gadolinium; Acceptor-like states; extraction; thin-film transistors (TFT); Indium oxide; photonic capacitance; density of states (DOS); Equivalent circuit; Capacitance; Zinc oxide; Thin film transistor
• ISSN: 0741-3106; 1558-0563
• DOI: 10.1109/LED.2013.2287511

We report a novel technique for simultaneous extraction of subgap donor- and acceptor-like density of states [g D (E) and g A (E)] over the subgap energy range (E V <;E<;E C ) using a single-scan monochromatic photonic capacitance-voltage technique in n-channel amorphous indium-gallium-zinc-oxide thin-film transistors. In the proposed technique, we applied two different equivalent circuit models for the photoresponsive carriers excited from g D (E) and g A (E) under depletion (V GS <; V FB ) and accumulation (V GS <; V FB ) bias by employing a sub-bandgap optical source that includes a relation between photon energy (E ph ) and bandgap energy (E g ) as h v = E ph <; E g .