This approach is being developed independently at various locations including the University of New South Wales,[1][2] Oregon State University,[3] Massachusetts Institute of Technology,[4] and Saule Technologies[5] Although inkjet printed solar cells were not a major focus previously due to their relatively low efficiencies, the appearance of perovskite solar cells, has led to a renewed interest in the development of inkjet printed solar cells, due to their nature of being solution processable.
[10] In 2011 Oregon State University was able to discover a way to create CIGS solar cells using an inkjet printer.
[11] In 2014, Olga Malinkiewicz presented her inkjet printing manufacturing process for perovskite sheets in Boston (USA) during the MRS fall meeting - for which she received MIT Technology review's innovators under 35 award.
Additional components might be added to affect the viscosity and the surface tension of the ink for improved printability and wetting on the substrate.
The printing is accomplished usually by a piezoelectric driver in the nozzles of the printhead, that is programmed to apply pre-set patterns of pressure to eject droplets.
In most cases several layers of functional materials are deposited on top of each other to generate a working solar cell.
The primary issue with inkjet printed solar cells is not actually with the cells themselves, but making sure that the manufacturing is optimized, such as the inks for printing and the drying processes; this requires the control and optimization of multiple variables, such as the "viscosity, volatility, and surface tension"[18] which can be modified by changing the solvent and modifying the solute.
Inkjet printing is being explored as a deposition technique for the electrode layers for silicon solar cells.
Although the use of inkjet printing for the deposition of this silver conductive grid has so far resulted in lower cell efficiencies than other deposition techniques, it is beneficial because it allows for the creation of an incredibly precise grid of any pattern without the need for complex and more wasteful manufacturing techniques such as lithography or etching.
Inkjet printing techniques have been explored for the manufacturing of thin-film CIGS solar cells,[14] and are of particular interest due to the extremely low waste from material deposition.
Reducing waste in the production process of CIGS cells is important because the costs of the light absorbing layer's components (copper, indium, gallium, and selenide) is comparatively much higher than other types of solar cells, mainly due to the rarity of In, Ga, and Se.