Ultrasonic Solar Panel Cleaning

Making solar cells from Silicon wafers involves several fabrication steps:

1) Etching silicon to remove unwanted material, followed by chemical and mechanical polishing. You clean the silicon with an alkaline solution before being rinsed in deionized water. Finally, it’s dried using compressed air or nitrogen gas.

After you treat the wafers with chemicals, you rinse them, but traces of the chemicals may remain. These chemical traces can shorten the lifespan of the solar cells, reduce their efficiency, and impact the next steps.

2) Performing wafer doping to create positive and negative charges on both sides of the cell. You then coat the wafers with metal contacts and encapsulate them in protective plastic packages. These processes often result in contamination of the wafer’s surface.

It is common for the wafers to be rinsed after chemical treatment, but traces of the chemicals may remain. These chemical traces may shorten the wafers’ life expectancy, reduce the solar cells’ efficiency, and hurt subsequent processes.

When manufacturers mask wafers while creating conductive paths, they must remove them after applying the conductive film.

In ultrasonic cleaning, operators can completely remove the masking substance without harming the thin and delicate conducting paths created during production. A complete precision cleaning is required to ensure the proper operation of solar cells.

3) Layering conducting and non-reflective films onto the front side of the wafer while covering the backside with a layer of aluminum. The operator then applies a thin film of silver over the top of the aluminum layer. Lastly, another layer of aluminum is deposited on top of the silver. 

One last cleaning process is necessary to ensure that the operation hasn’t introduced impurities into the casing of the sealed solar panel. Solar cells are delicate, and cleaning must be gentle. By using higher ultrasonic frequencies, ultrasonic cleaning systems can deliver cleaning action that is gentle and yet effective while still removing all contamination.

Crest Ultrasonics equipment and detergents effectively remove contaminants and residues quickly and entirely while leaving the performance of the underlying silicon wafers or glass sheets unaffected. 

An additional benefit is that the ultrasonic cleaning method works without harsh chemicals, using a bath of plain water or water with a mild detergent. Ultimately, Crest helps ensure that every solar panel is precision-cleaned after every step in the manufacturing process.