A recording medium and apparatus and method for managing defective areas are discussed. Generally, such devices comprise a fluid membrane that separates two or more fluids flowing through plural microchannels operatively associated with the membrane. An electric box front surface is generally flush with a cover plate front surface at the retracted configuration while the electric box is forwardly extended at the extended configuration. The upper capacitor electrode has a semiconductor layer, a barrier layer, and a metal layer. All members of this instrument family have the same fingering patterns, which are based on recorder fingerings. The head is positioned at a first radial location over the disk, and the head is servoed over the disk in response to the spiral seed tracks starting from the first radial location in order to write a first spiral servo track on the disk.