More than 100 SCHMID APCVD systems are already in use for solar cell mass production worldwide. Several research institutes are now also actively working on modern cell concepts such as PERL (Passivated Emitter and Rear Locally diffusion) or IBC (Interdigitated Back Contact) which can be produced more cost-effectively with the help of APCVD coatings.
“Our APCVD systems are very sophisticated and have proven their value in the mass production of IBC solar cells. Therefore, researchers will certainly find other ways to achieve high efficiency breakthrough cell concepts with this technology,” says Dr. Christian Buchner, Vice President of the SCHMID Group. And this is precisely what research institutes are working on. The globally active SCHMID Group’s APCVD system can apply boron and phosphorus diffusion sources in varying thicknesses and concentrations to provide flexibility in the design of modern emitters on all base materials. Moreover, it is possible to harmonize the dopant sources for a codiffusion with one another in a way that one high-temperature step is sufficient.
Contrary to other methods, the coating with APCVD (Atmospheric Pressure Chemical Vapor Deposition) is cost-effective and yet flexible, since multiple injection heads in series enable the application of the source layer and the cap layer in a single pass. The principle: gases stream out of separate channels, and when they come into contact with preheated wafers, they deposit a homogeneous glass layer. The wafers to be coated pass through the APCVD system in five parallel tracks. Thus, a throughput of up to 4000 wafers per hour is achieved.