In situ diagnostic methods for thin‐film fabrication: utilization of heat radiation and light scattering

Abstract

Deposition processes of Cu(In,Ga)Se 2 (CIGS) thin films were observed by informative and low-cost in situ monitoring means; the pyrometer technique, and the spectroscopic light-scattering (SLS) technique. Intensities of thermal radiation and scattered white light were profiled from outside the vacuum chamber during growth, using a monochromatic pyrometer and a small CCD spectrometer. The deposition process was studied by systematic variations of major process parameters of CIGS, such as the substrate temperature, Ga concentration and Se supply. Various film properties, including the deposition speed, thickness, compositional ratios, surface roughness and precipitation of Cu-rich phases have been monitored in situ.

Effect of Al addition on the characteristics of Cu(In,Al)Se2 solar cells

“…The stoichiometry of the film composition during the second stage was detected by the fall in substrate temperature owing to the higher emissivity of the Cu 2Àx Se phase than CIS [7]. The substrate temperature was measured by a pyrometer [8], which was placed perpendicular to the substrate surface. In this experiment, the aimed composition ratio of Cu/(In+Al) at the end of the second stage was fixed to 1.1 by adjusting the duration of the second stage.…”

Study of Band Alignment at CBD-CdS/Cu(In1-xGax)Se2 (x = 0.2 - 1.0) Interfaces by Photoemission and Inverse Photoemission Spectroscopy

“…Cu 0.93 (In 1-x Ga x )Se 2 absorber layers were prepared on Mo back contact over soda lime glass by means of conventional 3-stage co-evaporation using molecular beam epitaxy system [15]. CdS buffer layers were deposited on the CIGS layers by CBD [16,17].…”

Photoluminescence Analysis of Proton Irradiation Effects in Cu(In,Ga)Se2 Solar Cells

“…The polycrystalline CIGS films were grown by a three stage process using molecular beam epitaxy. 12) The composition ratios of Ga and Cu with respect to group III constitutes of the CIGS films, Ga/III and Cu/III were 0.54 and 0.89, respectively. The Ga/III composition ratio was gradient with the growth direction.…”