Imec simplifies i-PERC solar cell processing by implementing laser doping from ALD-Al2O3

Nov 27, 2013

Nanoelectronics research centre IMEC announced today that they have developed large area (156x156mm2) i-PERC-type silicon solar cells using a new processing sequence based on laser doping from a thin atomic layer deposited (ALD) aluminum oxide (Al2O3) layer to realize the local aluminum Back Surface Field (BSF) and Ni/Cu plating to form the front contact. The cells achieved average conversion efficiencies of 20.2%.

The new laser doping processing sequence eliminates the necessity of a firing step to create the local BSF in i-PERC solar cells. Combined with imec's Ni/Cu plating sequence for front contact formation, it provides a low temperature metallization solution for i-PERC cells. By avoiding high temperature conditions, passivation degradation of the rear Al2O3 layer, as well as optical degradation of the rear dielectric/metal stack are prevented, resulting in improved solar cell conversion efficiency. Additionally to the performance benefit, this new process sequence is extremely simple because the thin ALD Al2O3 acts at the same time as passivation layer and doping source, while processing enables in one step the contact patterning and the local BSF formation.

The complete solar cell process was executed at imec and the resulting 156x156mm2 i-PERC silicon cells on p-type Cz-Si achieved an average conversion efficiency of 20.2%. Even though only low temperature anneal was used, the high Fill Factor of the cells (up to 80%) indicates an excellent contact quality.

"Cost-of-ownership and process simplicity are key factor for the industry to adopt new technologies," stated Jozef Szlufcik, Si PV program director at imec. "Our achievement, implying a substantial simplification of the i-PERC manufacturing process, is an important step towards reducing the cost-of-ownership of i-PERC technology and as such, a milestone in bringing this high-efficiency technology for silicon solar cells to the market."

These results have been achieved in the framework of the imec's industrial affiliation program on advanced , dedicated to developing high performance and low cost Si PV-technologies.

Explore further: Imec, Meco present high efficiency and cost-effective copper technology for i-PERC-type Silicon Solar Cells

add to favorites email to friend print save as pdf

Related Stories

Recommended for you

Wireless sensor transmits tumor pressure

13 hours ago

The interstitial pressure inside a tumor is often remarkably high compared to normal tissues and is thought to impede the delivery of chemotherapeutic agents as well as decrease the effectiveness of radiation ...

Tim Cook puts personal touch on iPhone 6 launch

14 hours ago

Apple chief Tim Cook personally kicked off sales of the iPhone 6, joining in "selfies" and shaking hands with customers Friday outside the company's store near his Silicon Valley home.

Team improves solar-cell efficiency

Sep 19, 2014

New light has been shed on solar power generation using devices made with polymers, thanks to a collaboration between scientists in the University of Chicago's chemistry department, the Institute for Molecular ...

Calif. teachers fund to boost clean energy bets

Sep 19, 2014

The California State Teachers' Retirement System says it plans to increase its investments in clean energy and technology to $3.7 billion, from $1.4 billion, over the next five years.

User comments : 0