The Application Of Inkjet Printing In Fabrication Of Interdigitated Back Contact Solar Cells

The problem of environmental pollution and energy crisis make people pay more and more attention to using solar energy,photovoltaic industry has thus obtained rapid development.The core problem of the progression of photovoltaic industry is to enhance the power conversion efficiency and reduce the production cost.Interdigitated back contact(IBC)solar cell enjoys a promising market for its high power conversion efficiency,which is one of the highest of silicon solar cells.However,it also has a high production cost,the traditional manufacturing processes still needs to be improved.In this paper,inkjet printing technique is applied to fabricate the emitter and back surface field of IBC solar cells.My work includes three parts:(1)I print boron ink on the silicon substrates which have been modified to be hydrophobic,and find that perfect boron lines which have the finest width of 630 ?m can be made on the wafers after modification in the solution of n-Tetradecyltrichlorosilane and hexane at the volume ratio of 1:400.Then I carry on boron doping under different conditions,and finally fabricate the emitter successfully at 950? for 1h.The peak carrier concentration and junction depth and square resistance of the emitter is 3.41×1019 cm-3 and 0.59 ?m and 37.8 1 ?/sq,respectively.(2)I print phosphorus ink on the original surface of silicon wafers,and the finest width of phosphorus lines is 150 ?m.Then I carry on phosphorus doping in different conditions and finally choose the same annealing method as boron doping to fabricate back surface field successfully.The peak carrier concentration and junction depth and square resistance of the back surface field is 2.65×1019 cm-3 and 0.70?m and 44.7 ?/sq,respectively.(3)I use Quokka to simulate complete IBC solar cells based on the experimental data of the emitter and back surface field,then study the trend of energy loss and power conversion efficiency as I change the width of emitter.When the emitter's width is 830?m,the power conversion efficiency of our IBC solar cell reaches to 23%.This proves that inkjet printing can meet the requirements of fabricating the emitter and back surface field of IBC solar cells.