The solar photovoltaic (PV) industry has continued its rapid growth in recent years. The PV module production in 2019 is expected to exceed 120 GW, corresponding to around a 20% increase from 2018 production. A part of the reason for this significant growth in the PV market seems to be due to major increases in the solar market in India and the US. While PV technologies based on all material systems (Si, CdTe, CIGS) have seen increased production, the Si wafer-based technology has continued its dominance, with close to a 95% market share. However, the relative market shares of CdTe and CIGS have not grown significantly. In the Si technology itself, there was an emphasis toward the production of higher efficiency Passivated Emitter and Rear Contact (PERC) cells and bifacial cells. P-type PERC cells with efficiencies exceeding 23% have become the standard production. Furthermore, the difference between the efficiencies of monocrystalline and multicrystalline Si modules seems to have grown larger - concomitantly reducing the multicrystalline market share to less than 60% (compared to 70% in 2016).

Laboratory cell efficiencies have improved to record levels of 26.7% for mono-crystalline and 22.3% for multi-crystalline silicon wafer-based technology. Likewise, the highest lab efficiency in thin film technology is ~23.4% for CIGS and ~21.0% for CdTe solar cells. In addition, there has been remarkable progress in perovskite cells with efficiency exceeding 24.2%

This Special Issue aims to compile papers on all research aspects of measurement and characterization of photovoltaic materials and devices. We invite researchers, academicians, and industry technologists to contribute original research articles as well as reviews related to various PV technologies such as Crystalline Si, thin film technologies (CdTe, CIGS, amorphous Si:H), emerging solar cell technologies - organic solar, dye-sensitized, multi junction, nano-crystalline, perovskite, perovskite/silicon tandem cells and quantum dots.

Potential topics include but are not limited to the following:

• All research aspects related to current materials and solar cells
• Approaches for commercial production, focusing on precursor and feedstock materials, module design and processing, advances in device fabrication, and innovations in device fabrication e.g., roll to roll manufacturing
• New materials for PV applications, such as organics, quantum dots, thin-film Si, polymers, and bio-hybrids
• Device and process simulations
• Advanced module design and fabrication technologies
• Advanced measurement/characterization methods and instrumentation for in situ measurement, defect monitoring, and process control and performance, reliability testing, and standards
• Technology and process development in industry