Applications

The versality and high throughput of the Atmospheric Dry Etching (ADE) technology makes it suitable for various industrial silicon etching and texturing applications. 

Single side amorphous silicon removal for TOPCON solar cells

Tunnel oxide passivated contact (TOPCON) solar cells are seen as the next step to reach efficiencies higher than with the PERC process. TOPCON uses the high surface passivation quality of deposited amorphous silicon for their rear side, on top of a thin tunneling oxide. The state of the art deposition process however leads to parasictic deposition at the front of the wafer that needs to be removed.

The single sided nature of the ADE process is particularly well suited to the removal of the amorphous silicon from the front side of a wafer, during the manufacturing of a TOPCON solar cell. The a-Si can be etched either before of after annealing. The a-Si is removed from the top surface but also from the wafer 's edges during the ADE process. TOPCON Cells using ADE show high parrallel resistance.

ADE amorphous silicon removal

ONYX© TEXTURING PROCESS

The texturing process of solar cells is the etching step with highest added value. It modifies the surface of the wafer in order to create a micro/nano scale surface texture that increases the amount of light absorbed into the silicon, and therefore increase the overall efficiency of the cell. Current wet processes have limited efficiency and require the deposition of additional anti-reflective layers on top of the cell.

Nines ONYX texturing process delivers surface textures with superior optical properties and reflectivity as low as 2%.The cells look darker providing best in class aesthetic for all type of wafers, including multi-crystalline.

The amount of silicon removed to achieve theses textures is minimal, leading to cost saving not only on etching consumables but also on silicon, i.e. the wafers could enter the factory thinner yet the finished cell would have the same thickness as for a wet process.

Latest News

02/10/20 TOPCON application

ADE used for single side amorphous silicon removal.


25/05/18 NINES PV SECURES INVESTMENT FOR INDUSTRIALISATION

The €3 million investment is coming from InnoEnergy and supports the development of a high throughput industrial ADE production tool that is planned to be installed with leading Tier-1 PV manufacturer Hanwha Q CELLS.


More news...


> ADE leads to PERC efficiency over 20%

ADE texturing processes in an industrial PERC mc-Si and c-Si cell process result in more than 20% cell efficiency.The results were obtained in conjunction with Tier 1 cell manufacturer Hanwha QCells. 

NINES PV and Hanwha QCells are working together to integrate the ADE dry texturing process into the well established Q.ANTUM PERC process. Using diamond wire (DW) cut mc-Si wafers, the ADE process resulted in an uplift compared to the standard reference due to the superior texturing leading to higher current. No adjustment of the downstream steps were performed, yet the efficiency obtained reached 20.3%, that is +0.2% absolute improvement above the best reference (acidic textured).

The results were presented at the 2017 EUPVSEC conference in Amsterdam: " Industrial Plasma-Less Dry Texturing Method for Diamond Wire Cut mc-Si Wafers -the universal ADE texturing process ".

>> Download the poster here

ADE reflectivity vs alkaline texture
ADE_textured_DW_mc-Si_wafers

> Texturing diamond wire cut wafers

The ADE texturing process has been demonstrated with several types of crystalline wafers, inlcuding Cast wafers, Epitaxial layers, Diamond wire cut wafers, as well as amorphous deposited Si layers.

More specifically, for mc-Si diamond wire cut wafers, the ADE technology provides a high performance texturing solution for industrial customers willing to move from slurry cut to diamond wire cut wafers in order to avail of the full cost benefit that this technology brings. Several industrials have already evaluated succesfully the ADE texturing. The diamond wire wafering technology is expected to grow significantly over the coming years, as detailed by the ITRPV roadmap (www.itrpv.net). The flexibility of the process allows a large variety of texture and reflectivity, down to “black-silicon” level, as would be achieved by a RIE vacuum based process.

> ONYX© Process for AlBSF mc-Si

In collaboration with Fraunhofer ISE, Freiburg, Nines have demonstrated the ONYX texture process by incorporating the ADE technology in the Fraunhofer ISE pilot production line. The process developed lead to excellent results, with cell efficiencies superior to the standard wet acidic texturing process.

Nanotextured multicrystalline Al-BSF solar cells reaching 18% conversion efficiency using industrially viable solar cell processes. Bishal Kafle& al. Article DOI: 10.1002/pssr.201510219,physica status solidi (RRL).

>> Download the full text  LINK