Group III Impurity Doped Zinc Oxide Thin Films Prepared by RF Magnetron Sputtering

Abstract

The detailed study of electrical properties in group III impurity doped ZnO thin films prepared by rf magnetron sputtering is described. The resistivity is lowered by doping of B, Al, Ga and In into ZnO films. The characteristic features of ZnO films doped with group III elements except for B are their high carrier concentration and low mobility. Variation of the mobility with the impurity content is roughly governed by the ionized impurity scattering. It is shown that the doped ZnO films exhibit the resistivity dependence on film thickness below 300 nm.

Impurity-doped ZnO Thin Films Prepared by Physical Deposition Methods Appropriate for Transparent Electrode Applications in Thin-film Solar Cells

“…3 is mainly attributed to the increase in the level of the resulting resistivity distribution on the substrate surface described above. However, it should be noted that the resulting resistivity distribution on the substrate as well as the obtainable thickness dependence of resistivity in the thin films prepared by the MSDs were considerably affected by differences that can be associated with the target used, e.g., the kind of doped impurity and supplier of the target [7,8,[40][41][42]. In GZO thin films prepared with a thickness above 500 nm on substrates at 200 o C by dc-MSD and rf+dc-MSD, the influence of the deposition method used on the obtained electrical properties in GZO films differed from that found in AZO films described above.…”

Development of thin‐film Cu(In,Ga)Se2and CdTe solar cells

“…20 Doping of the conducting ZnO layer is achieved by group III elements, particularly with aluminum. 21 However investigations show boron to be a feasible alternative, as it yields a high mobility of charge carriers 22 and a higher transmission in the long-wavelength spectral region, giving rise to higher currents. 23 For high-efficiency cells the TCO deposition temperature should be lower than 150 C in order to avoid the detrimental interdiffusion across CdS/CIGS interface.…”

Contrasting transparent conductive properties of ZnO films on amorphous and crystalline substrates in view of thickness dependence

“…The dependence of the electrical transport parameters, including carrier concentration (n), Hall mobility (l), and resistivity (q), on film thickness represents the kind of material and quality of the film. 1,2 In general, carrier concentration and mobility monotonically increase with thickness. Crystallinity is poorest at the beginning of growth, but it gradually improves as the growth front departs from the interface.…”