Project: Cost efficient, upscalable and stable transparent conductive oxides for silicon solar cells based on passivated contacts.

Acronym	CUSTCO (Reference Number: JTC-2_2019_060)
Duration	01/09/2019 - 31/08/2022
Project Topic	This project targets the development of industrially feasible transparent conductive oxides (TCO) to reduce the cost of high efficiency silicon solar cells using full-area passivated contacts, which have demonstrated efficiencies above 25% in cleanroom and pre-production environment. While research and industry currently focus on silicon thin films, either amorphous (a-Si:H) or silicon oxide (SiOx)/polycrystalline silicon (pc-Si) fabricated in the range of 200°C to 900°C, respectively, the CUSTCO consortium will address the significant impact of the TCO on the cost and performance improvements of such devices and hence on the success for their industrialization. While the main focus will be on the TCOs, the silicon thin films will also be addressed since the overall contact properties and hence the performance and stability of the devices are defined by the tight interplay between both. TCO materials which are already widely used for thin film solar cells, displays or sensors will be tested for their applicability to such silicon wafer based solar cells and new materials will be explored or adapted. While the typical approach is to optimize the TCO for a given silicon contact system, we will first concentrate on a more holistic evaluation of the TCO and then choose the proper silicon-based contacts for device integration. The application of the developed a-Si or SiOx/pc-Si based contacts will allow for a wide TCO process window to utilize so far unexplored potential of these materials. Material improvements by hydrogenation of the TCO will also be addressed with the final goal to demonstrate a cost efficient, upscalable and stable TCO for a highly efficient (>24%) silicon solar cell. An important aspect of the project will be the substitution or at least a drastic reduction of Indium, which is a rare element but currently the most widely used in TCO materials.
Network	Solar Cofund 2
Call	Solar Cofund 2 Joint Call

Project partner

Number	Name	Role	Country
1	Fraunhofer ISE	Coordinator	Germany
2	MESA+ Institute of Nanotechnology. University of Twente.	Partner	Netherlands
3	CNRS	Partner	France
4	Fraunhofer ISE - LSC Labor- und Servicecenter Gelsenkirchen	Partner	Germany
5	Indeotec SA	Partner	Switzerland
6	Solmates BV	Partner	Netherlands
7	Sindlhauser Materials GmbH	Observer	Germany