Dielectric integrity of ion beam deposited aluminum oxide films in the 10–100 nm thickness range

Catastrophic electrical breakdown of thin Al2O3 reader gap films is becoming increasingly important for Giant Magneto-Resistive (GMR) recording heads. In this paper, we study the dielectric integrity of thin Al2O3 films in the 10–100 nm thickness range produced by ion beam deposition. The effects of substrate preparation, film thickness and assist beam parameters on electric breakdown are investigated. It was found that optimized films produced using an Al2O3 target break down at electric field strengths in the 8.5–9 MV/cm range.