title: Characteristics of Al-doped ZnO films grown by atomic layer deposition for silicon nanowire photovoltaic device.
abstract: We report the structural, electrical, and optical characteristics of Al-doped ZnO (ZnO:Al) films deposited on glass by atomic layer deposition (ALD) with various Al2O3 film contents for use as transparent electrodes. Unlike films fabricated by a sputtering method, the diffraction peak position of the films deposited by ALD progressively moved to a higher angle with increasing Al2O3 film content. This indicates that Zn sites were effectively replaced by Al, due to layer-by-layer growth mechanism of ALD process which is based on alternate self-limiting surface chemical reactions. By adjusting the Al2O3 film content, a ZnO:Al film with low electrical resistivity (9.84 x 10(-4) Omega cm) was obtained at an Al2O3 film content of 3.17%, where the Al concentration, carrier mobility, optical transmittance, and bandgap energy were 2.8 wt%, 11.20 cm2 V(-1) s(-1), 94.23%, and 3.6 eV, respectively. Moreover, the estimated figure of merit value of our best sample was 8.2 m7Omega(-1). These results suggest that ZnO:Al films deposited by ALD could be useful for electronic devices in which especially require 3-dimensional conformal deposition of the transparent electrode and surface passivation.
authors.affiliation: Department of Electrical and Electronic Engineering, Yonsei University, 262 Seongsanno, Seodaemun-Gu, Seoul 120-749, Republic of Korea.
authors.forename: Byeong-Yun
authors.initials: BY
authors.lastname: Oh
authors.forename: Jin-Woo
authors.initials: JW
authors.lastname: Han
authors.forename: Dae-Shik
authors.initials: DS
authors.lastname: Seo
authors.forename: Kwang-Young
authors.initials: KY
authors.lastname: Kim
authors.forename: Seong-Ho
authors.initials: SH
authors.lastname: Baek
authors.forename: Hwan Soo
authors.initials: HS
authors.lastname: Jang
authors.forename: Jae Hyun
authors.initials: JH
authors.lastname: Kim