Design, simulation, fabrication and measurement of a 25 nm, 50% slider

In the near future magnetic hard disk drives are expected to achieve densities approaching 10 gigabits per square inch. This will require magnetic spacings between the read/write transducer and magnetic disk of less than 25 nm. Such spacings are being referred to in the industry as "near contact". This paper presents a 50%/25 nm slider with shaped rails and sub-ambient pressure zones. The sliders were fabricated using chemical etch techniques, and their spacings were measured against a glass disk by interferometry. It was found that the measured spacings were substantially greater than the design values. However, stylus measurements of the etch profiles indicated slopes different from those incorporated in the simulator. After accounting for these slopes in the simulator input data we found that the subsequently obtained simulation results were in good agreement with measurements.