Electrostatic InkJet printed silver grids for non-vacuum processed CIGS solar cells

Printed electronics is gaining increasing research attention and a growing market share due to it's lower production cost and easy scalability. Here, we demonstrate the use of Electro-Static Inkjet (ESJET) printing technology to deposit silver nanoparticle (Ag nps) inks as grid electrodes for non-vacuum processed Cu(In,Ga)S₂ (CIGS) solar cells, bridging the gap between high viscosity screen printed materials and low viscosity inkjet processes. We investigated the effect of composition of Ag inks compositions and the corresponding sintering condition of ESJET printed Ag grids on the photovoltaic performance of CIGS solar cells. High sintering temperatures (220 °C) of the printed Ag electrodes caused a significant performance loss in the CIGS cells. However, sintering at 160 °C produced cells with efficiency comparable to reference cells using thermal evaporated Ag grids. Results from stability test (ISOS-D-1) shows the device efficiency of devices with ESJET printed Ag grids decreased from 11.14 to 10.44% after 3 months in air without encapsulation, corresponding to efficiency loss of approximate 0.6%. Our work demonstrates that ESJET printing is a viable method for deposition of photovoltaic metal grids, enabling finer electrode patterns, minimizing material waste, and significantly reducing the production cost of thin film solar cells.