Description of field of research:

With the continuous decrease in cost, photovoltaic (PV) has the potential to be one of the most important energy sources for human beings in the coming decades. It is also an essential weapon to confront the threat of climate change we are facing. To reduce the levelized cost of electricity (LOCE) of PV, solar cells need to have high energy conversion efficiency and be stable for a long time.

Bulk defects in solar cells stimulate the recombination of light generated charge carriers which dissipate the absorbed light energy into heat instead of electricity. Therefore, they can be very detrimental to the efficiency of solar cells. As the PV industry moves towards more advanced cell structures which minimise the recombination at the surfaces and contacts, recombination due to bulk defects now has a more pronounced impact. Bulk defects can also cause degradation over a long time, thus reducing the stability of solar cells. Therefore, understanding the properties of detrimental bulk defects is critical for making our solar cells better.

In this project, we aim to investigate the properties of those detrimental bulk defects that impact space and terrestrial cells. We will use a combination of different types of advanced characterisation techniques, including deep level transient spectroscopy, lifetime spectroscopy, and some machine learning based data analysis. Various types of defects relevant to the state-of-the-art solar cells will be investigated, including oxygen related ring shape defects, light induced degradation related defects, defects formed during space application, etc.

School

Photovoltaic and Renewable Energy Engineering

Research areas

Solar cells, photovoltaic, semiconductor, renewable energy

In this project, you will work with the ACDC research team (Artificial intelligence, Characterisation, Defects and Contacts) at UNSW. The research team is made up of around 20 researchers and students. The group has a very friendly environment. We have students who finished a ToR project with us, stayed for their 4th-year thesis, and later transitioned to a PhD in the group.

You will mainly work with Dr. Yan Zhu. He has worked on the characterisation of defects in solar cells for more than five years. He did his bachelor's degree in mechanical engineering, so he understands the difficulties of doing research in an unfamiliar area. Therefore, he is willing to spend time sharing the necessary knowledge and skills. We will ensure a smooth start of your project, and throughout its duration, you will have a better chance to develop independent research skills.

The outcomes of this project include: improved characterisation techniques for detrimental bulk defects in space and terrestrial solar cells, a better understanding of the properties of those defects, and potential methodologies to help mitigate those defects during solar cell fabrication. This task is not easy as many defects have a very dilute concentration (less than one defect per 10 billion silicon atoms). However, we will equip you with the most advanced defect characterisation techniques and make you the best detective for those defects.

You will have the opportunity to present your work at research conferences, or even publish your results as a journal paper. Our previous ToR students presented their work in the US and Japan!

We also hope by the end of the project, you will have a better understanding of the basic skills needed for conducting good research. More importantly, we hope you can enjoy doing research, as we think it is the most interesting job in the world.

In our research lab, we have a wide variety of equipment for defect investigation, some of the equipment is one of a kind in the whole world. You will have the opportunity to master these advanced characterisation techniques, or even make improvements. We also have a variety of samples provided by our industrial partners for you to investigate.

Apart from guidance from Dr. Yan Zhu, you will also have the chance to get advice from other members of the ACDC team. We will use our experience and expertise to help you build the capabilities to solve any problems you might encounter.

Website of our research group: https://www.acdc-pv-unsw.com/"