Abstract
Herein, we performed a comparative study of plasma-enhanced atomic layer deposition (PEALD) of SnO2 films using Sn(dmamp)2 as the Sn source and either H2O plasma or O2 plasma as the oxygen source in a wide temperature range of 100–300 °C. Since the type of oxygen source employed in PEALD determines the growth behavior and resultant film properties, we investigated the growth feature of both SnO2 PEALD processes and the various chemical, structural, morphological, optical, and electrical properties of SnO2 films, depending on the oxygen source. SnO2 films from Sn(dmamp)2/H2O plasma (SH-SnO2) and Sn(dmamp)2/O2 plasma (SO-SnO2) showed self-limiting atomic layer deposition (ALD) growth behavior with growth rates of ~0.21 and 0.07–0.13 nm/cycle, respectively. SO-SnO2 films showed relatively larger grain structures than SH-SnO2 films at all temperatures. Interestingly, SH-SnO2 films grown at high temperatures of 250 and 300 °C presented porous rod-shaped surface morphology. SO-SnO2 films showed good electrical properties, such as high mobility up to 27 cm2 V−1·s−1 and high carrier concentration of ~1019 cm−3, whereas SH-SnO2 films exhibited poor Hall mobility of 0.3–1.4 cm2 V−1·s−1 and moderate carrier concentration of 1 × 1017–30 × 1017 cm−3. This may be attributed to the significant grain boundary and hydrogen impurity scattering.
Highlights
Tin(IV) oxide (SnO2 ) has received considerable research attention due to its excellent electrical conductivity, optical transparency, and chemical stability. This has been extensively utilized in various applications, such as gas sensors, batteries, fuel cells, photovoltaic cells, photodetectors, transparent electronics, and thin film transistors (TFT) [1,2,3,4,5,6,7]
The exploitation of atomic layer deposition (ALD) SnO2 films for state-of-the-art devices is increasing because ALD can produce dense, uniform, and conformal films on complex three-dimensional substrates at relatively low deposition temperatures [13]
Reported the low-temperature (~100 ◦ C) SnO2 plasma-enhanced atomic layer deposition (PEALD) process using tetrakis(dimethylamino)tin (TDMASn) and O2 plasma at a high growth rate of 0.17 nm/cycle, and a highly efficient perovskite solar cell was demonstrated using 100 ◦ C-deposited SnO2 as an electron-selective layer [15]
Summary
Tin(IV) oxide (SnO2 ) has received considerable research attention due to its excellent electrical conductivity, optical transparency, and chemical stability. To obtain high-quality ALD SnO2 film at wide process temperatures, various Sn precursors, including Sn halides and metal–organic Sn-precursors in combination with different co-reactants, like H2 O, O3 , H2 O2 , and other plasma oxygen sources, have been investigated. Reported the low-temperature (~100 ◦ C) SnO2 PEALD process using tetrakis(dimethylamino)tin (TDMASn) and O2 plasma at a high growth rate of 0.17 nm/cycle, and a highly efficient perovskite solar cell was demonstrated using 100 ◦ C-deposited SnO2 as an electron-selective layer [15]. Explored SnO2 PEALD using halogenated SnCl4 precursor and O2 plasma This showed improved growth rate, film purity, and crystallinity compared with the thermal ALD process using SnCl4 /H2 O [16]. The use of H2 O plasma for PEALD SnO2 growth has not been reported yet, and PEALD SnO2 films showed excellent properties of high deposition rate, excellent crystallinity, and low impurity concentration
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
