To compete with other sources of electricity, the photovoltaic (PV) industry continuously strives to reduce the levelized cost of electricity (LCOE in $/kWh). So far, this has been mainly achieved by reducing the manufacturing costs of PV modules via economies of scale and improvements in module efficiencies. Further reductions in the LCOE requires in addition to improve PV modules so that they yield more energy (kWh/kWp) over their useful lifetime in the field (typically >20 years). As a result, the PV industry is developing novel PV modules concepts that tick all the boxes: (i) low manufacturing cost, (ii) high-efficiency, (iii) high energy yield, and (iv) low degradation rate in the field. Bi-facial glass-glass PV modules, which collect light from both sides and are more durable than conventional mono-facial PV modules, are among these novel PV module concepts. Cost analysis reports have shown that the crystalline silicon (c-Si) wafer and screen printed silver (Ag) contacts contribute significantly to the overall manufacturing costs of bifacial PV modules. To reduce manufacturing costs, both the c-Si wafer thickness and Ag consumption per c-Si solar cell should be reduced without compromising manufacturability and efficiency.
The focus of this PhD thesis will be to develop industrially-feasible methods to fabricate high-efficiency (>20%) thin (<120 μm) bi-facial c-Si cells. The goals include: (i) evaluating and improving optical confinement, (ii) developing a high-performance contacting scheme that uses less than 10 mg of Ag per cell, (iii) evaluating and improving advanced cell interconnection, and (iv) developing easy and robust handling of thin c-Si wafers during processing. Experimental tests would be conducted on both test structures and complete solar cell devices using equipment available in imec’s state-of-the-art R&D S-line.
This PhD thesis will make use of advanced characterization tools (examples: contact resistance measurement, Suns-Voc measurement, finished cell current-voltage measurements) and material analysis techniques (examples: scanning electron microscopy, energy dispersive spectroscopy, x-ray fluorescence) available at imec. This research will also develop and optimize analytical modeling tools that support experimental observations.
- Specialization in Microelectronics, Silicon Photovoltaics, and/or Chemistry seen as an important plus.
- Excellent written and verbal communication (in English) skills.
- You are curious, autonomous, dynamic and enjoy both practical and modeling work.
- Enthusiastic to work in inter-disciplinary team.
Type of work:
15% literature study, 60% experimental, 25% characterization and modeling.
Supervisor: Jef Poortmans
Daily advisor: Loic Tous
When you apply for this PhD project, mention the following reference code in the imec application form: ref. SE 1704-23.