Inkjet printing of cross point passive matrix devices

Methods of manufacturing a cross-point device such as an organic ferroelectric memory array can use inkjet printing from solution in ambient conditions to deposit electrodes 200 and regions of functional material 150 such as ferroelectric material or semiconductor material between top 200 and bottom 100 electrodes at the intersections, thereby reducing the need for lithography and planarising techniques. In some embodiments, two or three sub-arrays of overlapping or interlacing crossed electrodes are formed, with areas of dielectric material (fig 4c; 160b, 160c) printed between sub-arrays of electrodes to electrically insulate the arrays from one another, so that regions of functional material which are part of adjacent cross-point arrays at least partially overlap on the same vertical level. Intersecting electrodes for each array may be at an angle to one another other than 90 degrees (see figs 9). A wetting layer may be deposited on the functional material prior to deposition of the electrodes.