Atomic layer deposition of Al-doped ZnO thin films

Abstract

Articles you may be interested inAtomic layer deposition has been used to fabricate thin films of aluminum-doped ZnO by depositing interspersed layers of ZnO and Al 2 O 3 on borosilicate glass substrates. The growth characteristics of the films have been investigated through x-ray diffraction, x-ray reflection, and x-ray fluorescence measurements, and the efficacy of the Al doping has been evaluated through optical reflectivity and Seebeck coefficient measurements. The Al doping is found to affect the carrier density of ZnO up to a nominal Al dopant content of 5 at. %. At nominal Al doping levels of 10 at. % and higher, the structure of the films is found to be strongly affected by the Al 2 O 3 phase and no further carrier doping of ZnO is observed.

Atomic Layer Deposition of Al‐doped ZnO Films Using Aluminum Isopropoxide as the Al Precursor

“…Phase analysis was performed by X‐ray diffraction (XRD) on as‐deposited AZO films at 200°C on borosilicate glass substrates at various Al source temperatures, as shown in Figure 4. The (100)‐oriented wurtzite structure could be found in ALD‐grown AZO films with a deposition temperature range of 200 to 350°C,35–37 and (002)‐oriented AZO films with a deposition temperature range of 150 to 250°C were also reported in the literature 38–40. Moreover, Baji et al41 and Gong et al42 found that the orientation of ALD‐grown AZO film depended on the deposition temperature.…”

Electronic structure of conducting Al-doped ZnO films as a function of Al doping concentration

“…The ALD growth technique can provide good quality film with well-controlled thickness and composition due to its intrinsically self-limiting growth mechanism [7,12]. Given these advantages, Al-doped ZnO films deposited by ALD have been studied in terms of their growth conditions, doping mechanism and their electrical and optical properties [8,9] n simple changes of electrical properties depending on the Al contents and has explained the electrical conducting properties of AZO films by their physical structure and optical properties [3,9,10]. Yet in addition to the physical and optical changes of AZO films, the origins of conducting properties are strongly correlated to the electronic structure of the film, i.e., the band gap, conduction band, and band alignments.…”

Efficiently suppressed thermal conductivity in ZnO thin films via periodic introduction of organic layers

“…[10][11][12] Moreover, the relatively high lattice thermal conductivity of ZnO enables the realization of potentially large gains in thermoelectric performance if it could be reduced. 12,13 Recently, we successfully fabricated inorganic-organic SL structures of Al-doped ZnO and HQ by the combined ALD/MLD technique and demonstrated that the addition of organic layers into the structure of Al-doped ZnO does not result in a notable impairment of the Seebeck coefficient and electrical conductivity of the material; the Seebeck coefficient and resistivity values were -60μV/K and 70 mΩcm, respectively, for a (Zn0.98Al0.02)O sample with a 49:1 inorganic to organic ratio.…”