Team leader: Kaining Ding
The silicon Heterojunction (SHJ) group deals with the material and process development for SHJ solar cells. The process development covers the whole chain of the SHJ solar cell fabrication from the wet-chemical preconditioning of crystalline silicon wafers to the growth of functional thin-films using various deposition techniques and the final post-deposition thermal treatment. An import aim is to standardize the processing of highly efficient a-Si/c-Si SHJ solar cells as a high quality base line. The handling of very thin wafers, the application of light trapping methods and the realization of novel SHJ based cell concepts are further subjects of the process development. The material development focuses on the fabrication and characterization of silicon alloys as well as their implementation in SHJ solar cells. In particular, amorphous and microcrystalline silicon oxide and carbide (both stoichiometric and off-stoichiometric) are introduced as intrinsic buffer and doped contact layer, respectively. Another working field of the group in collaboration with the Simulation and the Optics group is the optoelectronic simulation of the SHJ solar cell aiming at a deeper understanding of the device working principle and support for the interpretation of experimental results.