At this year’s SiliconPV, which will take place from 19 to 22 March 2018 in Lausanne, Switzerland, ISFH will hold 5 oral as well as 5 visual presentations. In addition, short tutorials will be given on Sunday, 18 March, preceding the conference, to update young engineers and young scientists on this fast-developing field. Two of these tutorials will be co-tutored by ISFH.

The first one is entitled “Understanding and controlling lifetime killers in p-type and n-type silicon wafers” by Prof. Jan Schmidt, while the second is called “Physics of passivating contacts and high temperature processes: how to get a maximum voltage from your cells” by Prof. Robby Peibst. The first deals with the impact of impurities in the silicon material on the solar cell performance, the second tutorial will provide insights into the simultaneous optimization of surface passivation and majority carrier extraction by passivating contacts based on physical modelling

On Monday morning Dr. Felix Haase presents in his talk “Laser Contact Openings for Local Poly-Si-Metal Contacts” in Session 1: Passivating Contacts how laser contact openings enable local, damage-free contacting of passivating poly-Si on oxide (POLO) contacts. In a laboratory process, a record efficiency of 26.1 % was thus achieved for p-type silicon. The laser contact openings allow local contacting of the poly-Si with non-firing-through screen printing pastes.

On Monday afternoon, Dr. Henning Schulte-Huxel will present on his poster “1-I-01 – Yield Analysis and Comparison of GaInP/Si and GaInP/GaAs Tandem Solar Cells” in Poster Session 1 a new yield model for tandem solar cells (e. g. Si + III/V, Perovskite or other) for which cell data but no adequate outdoor measurements are yet available. It takes into account spectral effects as well as the module temperature depending on efficiency, irradiation and wind. The model is shown in the application for the comparison of a GaInP top cell on a GaAs or Si bottom cell.

Lailah Helmich will give a talk on “In-situ characterization of electron-assisted regeneration of Cz-Si solar cells” in Session 5: Silicon Materials and Defect Engineering on Tuesday. The aim is the in-situ examination of the regeneration of the boron-oxygen defect at elevated temperature (the regeneration temperature) in the dark on PERC solar cells. Different constant voltages are applied which determine the electron concentration and the recombination current of the cell is measured. This makes it possible to draw conclusions about the influence of electrons on regeneration kinetics.

In Session 9: Silicon Materials and Defect Engineering on Wednesday, Boris Veith-Wolf will present in his lecture “Reassessment of Intrinsic Lifetime Limit in n-type Crystalline Silicon and Implication on Maximum Solar Cell Efficiency” a new parameterization of the intrinsic lifetime for n-type crystalline silicon. This new parameterization has implications concerning the maximum reachable efficiencies in n-type silicon solar cells, which are higher than previously assumed.

Marc Halbich introduces in Poster Session 3 two different approaches to reduce the parasitic absorption in the PEDOT:PSS layer at the cell rear of silicon solar cells: (i) by adjusting the PEDOT:PSS layer thickness, and (ii) by improving the transparency of the PEDOT:PSS layer by adding non-conducting sorbitol to the precursor dispersion. The title of the poster is “Reduction of Parasitic Absorption in PEDOT: PSS at the Rear of c-Si Solar Cells“.

In the same Session, Valeriya Titova reports on the impact of annealing and hydrogenation on TiOx passivation quality. She also implements her optimized ALD-TiOx as electron-selective full-area rear contacts into n-type silicon solar cells and reaches efficiencies up to 20.1% after low-temperature annealing, as shown in “Electron-selective Atomic-layer-deposited TiOx Layers: Impact of Posttreatments and Implementation into n-type Silicon Solar Cells” (3-B-22).