Abstract
Cathodoluminescence (CL) has been measured at 10K in cross-section and plan-view configuration on Cu(In,Ga)Se2 thin films with Ga-grading as they are used in high-efficiency solar cells. Measurements on cross-section samples show the vertical profile of the emission energy to correspond to the band-gap profile of the film as calculated from measurements of the Ga-grading. Hence, the CL method is capable to directly measure the band-gap grading in semiconductor thin-films, but often the influence of the grading on the emission energy is generally ignored in recent literature. At the same time, we observe a strong drift of excited charge carriers toward the minimum of the band-gap. The transport process can be explained by the quasi-electric field induced by the Ga-grading and applied to determine transport properties of the Cu(In,Ga)Se2 material. Implications for luminescence investigations on band-gap graded thin-films are discussed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: 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.