Air-Stable CuInSe₂ Nanocrystal Transistors and Circuits via Post-Deposition Cation Exchange

Journal Article · Fri Feb 01 00:00:00 EST 2019 · ACS Nano

DOI:https://doi.org/10.1021/acsnano.8b09055· OSTI ID:1566579

Wang, Han  ^[1]; Butler, Derrick J. ^[2]; Straus, Daniel B.  ^[3]; Oh, Nuri  ^[4]; Wu, Fengkai ^[2]; Guo, Jiacen ^[2]; Xue, Kun ^[1]; Lee, Jennifer D.  ^[3]; Murray, Christopher B. ^[5]; Kagan, Cherie R.  ^[6]

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1. Univ. of Pennsylvania, Philadelphia, PA (United States). Dept. of Electrical and Systems Engineering
2. Univ. of Pennsylvania, Philadelphia, PA (United States). Dept. of Materials Science and Engineering
3. Univ. of Pennsylvania, Philadelphia, PA (United States). Dept. of Chemistry
4. Univ. of Pennsylvania, Philadelphia, PA (United States). Dept. of Electrical and Systems Engineering; Hanyang Univ., Seoul (South Korea). Division of Materials Science and Engineering
5. Univ. of Pennsylvania, Philadelphia, PA (United States). Dept. of Materials Science and Engineering; Univ. of Pennsylvania, Philadelphia, PA (United States). Dept. of Chemistry
6. Univ. of Pennsylvania, Philadelphia, PA (United States). Dept. of Electrical and Systems Engineering; Univ. of Pennsylvania, Philadelphia, PA (United States). Dept. of Materials Science and Engineering; Univ. of Pennsylvania, Philadelphia, PA (United States). Dept. of Chemistry

Colloidal semiconductor nanocrystals (NCs) are a promising materials class for solution-processable, next-generation electronic devices. However, most high-performance devices and circuits have been achieved using NCs containing toxic elements, which may limit their further device development. In this work, we fabricate high mobility CuInSe₂ NC field-effect transistors (FETs) using a solution-based, post-deposition, sequential cation exchange process that starts with electronically coupled, thiocyanate (SCN)-capped CdSe NC thin films. First Cu⁺ is substituted for Cd²⁺ transforming CdSe NCs to Cu-rich Cu₂Se NC films. Next, Cu₂Se NC films are dipped into a Na₂Se solution to Se-enrich the NCs, thus compensating the Cu-rich surface, promoting fusion of the Cu₂Se NCs, and providing sites for subsequent In-dopants. The liquid-coordination-complex trioctylphosphine–indium chloride (TOP–InCl₃) is used as a source of In³⁺ to partially exchange and n-dope CuInSe₂ NC films. We demonstrate Al₂O₃-encapsulated, air-stable CuInSe₂ NC FETs with linear (saturation) electron mobilities of 8.2 ± 1.8 cm²/(V s) (10.5 ± 2.4 cm2/(V s)) and with current modulation of 10⁵, comparable to that for high-performance Cd-, Pb-, and As-based NC FETs. The CuInSe₂ NC FETs are used as building blocks of integrated inverters to demonstrate their promise for low-cost, low-toxicity NC circuits.

• Research Organization: Energy Frontier Research Centers (EFRC), Washington D.C. (United States). Center for Advanced Solar Photophysics (CASP); Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: AC52-06NA25396
• OSTI ID: 1566579
• Journal Information: ACS Nano, Vol. 13, Issue 2; ISSN 1936-0851
• Publisher: American Chemical Society (ACS)
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
solar (photovoltaic)
solar (fuels)
solid state lighting
bio-inspired
electrodes - solar
defects
charge transport
materials and chemistry by design
optics
synthesis (novel materials)
synthesis (scalable processing)
nanocrystals
doping
solution process
copper indium diselenide
stoichiometry
field effect transitors
integrated circuits