Asian solar cell manufacturer selects Meyer Burger
Meyer Burger has concluded a strategically important contract with a leading Asian cell manufacturer.
The company will supply its HELiAPECVD and HELiAPVD coating systems to the firm who will use the tools in the manufacturing of high-performance heterojunction solar cells (HJT).
The total order volume amounts to around CHF 14 million ($15.76 US million) and delivery of the systems is planned for the first quarter of 2014.
The HELiA-type systems form the key components of a production line to manufacture disruptive technology, heterojunction solar cells.
The production line has the capacity to turn out 2,400 W/h. HJT solar cells have very high efficiencies which are currently in excess of 21 percent, as well as a very low temperature coefficient of around 0.20 percent/K and are used by the customer primarily for rooftop installations.
HELiAPECVD "“ maximum passivation
The key to the production of high-efficiency heterojunction solar cells are high-quality amorphous silicon layers (a-Si). HELiAPECVD systems enable the deposition both of intrinsic a-Si layers for the passivation and of doped layers for the manufacture of the electrical structures of the heterojunction cells.
The deposition of the a-Si layers is carried out by means of PECVD (plasma-enhanced chemical vapour deposition) in a quasi-continuous process. A patented plasma reactor - the S-Cube - was developed for this purpose by Roth & Rau. It is claimed to guarantee homogenous deposition of a-Si layers with excellent passivation and electrical properties.
HELiAPVD "“ low-cost TCO coating
The contacting of heterojunction cells is carried out on both sides by means of transparent, conductive oxide layers (TCO), deposited using PVD (physical vapour deposition in special magnetron sputtering) in a continuous process.
In the HELiAPVD sputtering unit, different contact layers (also multiple layers) can be deposited sequentially on the front and rear of the wafers, without the need to turn the wafers between the coating processes. Cylindrical sputter magnetrons enable a high target utilisation of over 85 percent to be achieved, ensuring a cost-effective coating process.
