the influence of an applied electric field this is accomplished by applying a voltage bias to one of the desired conductive elements 111 for a color display three different phosphors are used to emit red green and blue light three distinct electrophoresis steps would thus be required one for deposition of each phosphor type the plate on which the phosphorescent materials are to be deposited is placed opposite another conductive plate in a solution in which the materials are suspended and in which these materials are charged by means for example of an ionizable electrolyte the charged phosphorescent materials are attracted to the plate on which they are to be deposited by applying an electric field between the two plates the phosphors 112 are deposited in the area and manner shown in fig1 leading to the desired sloped sides upon which reflective layer 114 is formed as previously described the black matrix and phosphor are self aligned in this method of the invention and this method has the further advantage of requiring only a single photolithographic step a final method of the invention is described with reference to fig1 21 and results in the structure of fig4 in which the sloped reflective layer is offset a distance from the phosphors beginning with the fig6 structure the photoresist mask is used as an etch mask for underlying conductive layer 120 which is etched as.