New Publication: Transparent Conductive Oxides as Back Contacts for CIGS Solar Cells

Assessment of transparent conductive oxides as back contacts for inline‑fabricated Cu(In,Ga)Se₂ solar cells

A second recent publication from the Hi‑BITS consortium, also published in Journal of Physics: Energy, investigates the use of transparent conductive oxides (TCOs) as alternative back contacts for CIGS solar cells.

Conventional CIGS devices rely on opaque molybdenum (Mo) back contacts, which limit options for bifacial illumination and semi‑transparent designs. This study evaluates whether selected TCO materials can meet the electrical, optical, and processing requirements needed for integration into inline‑fabricated CIGS devices.

🔗 Read the full publication:
https://zenodo.org/records/17435834

Exploring Alternatives to Conventional Back Contacts

The paper systematically examines several TCO materials with respect to:

• Electrical conductivity and contact resistance

• Optical transparency, relevant for rear‑side illumination

• Thermal and chemical stability under CIGS processing conditions

• Compatibility with inline manufacturing workflows

The results highlight that while challenges remain, certain TCOs offer a promising balance between transparency and conductivity, without requiring complex protective interlayers. The study also demonstrates laser‑based structuring as an effective approach for device patterning when using transparent back contacts.

Implications for Advanced Device Architectures

The findings contribute to the broader development of CIGS architectures that enable bifacial operation, photon recycling, or semi‑transparent applications. By addressing both material selection and process integration, the work provides valuable guidance for researchers and technologists working on next‑generation thin‑film photovoltaics.

Open Access Publication

The article is published open access and is freely available via Zenodo, supporting knowledge sharing and further innovation in the field.