This tutorial was intended for young researchers (students and post-graduates within three years of degree completion) who are active in the field of thin-film solar cells and wanted to learn the fundamentals of characterization methods that are being used in research and development of these materials and devices.
8:30 am – 8:35 am—Welcome
8:35 am – 9:50 am—Part I: Thomas Paul Weiss
Device Characterization and Modeling
Basic concepts of electrical characterization using IV, QE, EBIC, C-V and C-f. Discussion of characteristic features of QE and I-V curves and how to extract the diode parameters using a 1-diode model. EBIC as a tool to access the carrier collection function and its connection to the device QE. Various contributions of a solar cell to its capacitance and how C-V and C-f measurements can be employed to extract doping densities, charge-carrier barriers and deep defect levels.
9:50 am – 10:20 am—Break
10:20 am – 11:35 am—Part II: Matthias Maiberg
Characterization of Thin-Film Semiconductors by Time-Resolved Luminescence
Introduction to measurement and analyzation of time-resolved luminescence (TRL) in photovoltaic thin-film semiconductors. Discussion of various techniques for measurement of TRL as well as advantages and disadvantages. Examples for luminescence decay curves from measurements on Cu(In,Ga)Se2 and Cu2ZnSnSe4. Classification of these luminescence transients and determination of material parameters using simulations.
11:35 am – 12:45 pm—Break
12:45 pm – 2:00 pm—Part III: Michelle Mezher
Soft X-Ray and Electron Spectroscopy
Introduction to several soft x-ray characterization techniques, including x-ray and UV photoelectron spectroscopy, inverse photoemission spectroscopy and x-ray emission spectroscopy. Discussion includes how they can be used to determine the electronic and chemical structure of surfaces and interfaces in photovoltaic devices.
2:00 pm – 2:30 pm—Break
2:30 pm – 3:45 pm—Part IV: Jacob Gruber and Jose J. Chavez
Introduction to Atomistic Modeling for Materials Characterization
Introduction to atomistic modeling in general. Several example applications for the study of mechanical behaviors of materials while avoiding potential pitfalls. Along with post processing tools, application for the study of structure and behavior of defects, analysis of bulk properties from models of atomic interactions, as well as of synthesis processes for numerous materials systems.
3:45 pm – 5:00 pm—Part V: Tao Song
Device Design and Modeling of Thin-Film Photovoltaic Devices
Basic design principles of thin-film solar cells and techniques. Numerical simulation to support interpretation of experimental results. Examples to illustrate the importance of device modeling, including the impact of material parameters on cell performance, the energy band alignment and interface recombination, as well as the grain boundary and non-uniformity issues of thin-film solar cells.
5:00 pm—Closing Remarks