Comparison of current spreading in stripe contact semiconductor lasers

The current profile at the active layer of an oxide stripe semiconductor laser is compared with those where there is an additional current channelling layer. For 3 ¿¿m and 10 ¿¿m stripe widths, it is found that a current channelling layer of 1 ¿¿m thick marginally improves the current within the stripe width by between 2% to 6%, but, more importantly, it eliminates the dip in the current profile at the centre of the stripe for the larger stripe width. For much larger stripe widths, such as at 20 ¿¿m, the current channelling layer needs to be correspondingly thicker to be effective in removing the dip in the current profile at the centre of the stripe.