Abstract

We have investigated He + -and Fe + -ion bombardments in the electrical isolation of InP/InGaAs HBT and n-InGaAs structures.Single energy of He -ions were bombarded at room temperature whereas multi-energy Fe + -ions were bombarded at 77K and room temperatures.At RT bombardment,maximum Rsh of 5x10 4 Ω/sq and 8x10 4 Ω/sq for He-ions whereas 1x10 5 Ω/sq and ~10 6 Ω/sq for Fe- ions were obtained for the HBT and n-InGaAs structures, respectively.At 77K bombardment,an increase of over five orders of magnitude in Rsh (~5x10 6Ω/sq)when compared to un-bombarded samples,which is very close to the intrinsic value for n-InGaAs (~1x10 7Ω/sq).This is significantly higher than the R bombardment results.