Insulating material is deposited onto a gate dielectric surface separating two wordline stacks, the method comprising the steps of:. An optical material at least partially fills cavities between the structures. The cleaning device is constructed and arranged to clean the drop-carrying surface by employing a flow of cleaning fluid or another cleaning matter such as small particles the flow being arranged to prevent contaminating back flow. The viewing apparatus includes the body andor the lid having at least one slot therein and at least one strip having the indicia thereon. A first portion of the currents passes into a gap between the first filter and the data recording surface.