A 225-nm-thick vertical-structure light-emitting diode inhibiting confined waveguide mode

Abstract

An ultrathin vertical-structure light-emitting diode (LED) that inhibits confined optical modes is thought to be an ideal architecture for light extraction in which all emissions will couple to extraction modes. Here, we reduce the vertical-structure LED thickness down to ∼225 nm by combining metal-based bonded III-nitride-on-silicon and inductively coupled plasma reactive ion etching without a hard mask. The experimental results confirm that optical waveguide modes confining light are inhibited and all emissions would couple to extraction modes naturally. Moreover, the bottom Ag electrode functions as a reflector to effectively enhance light extraction.

Simultaneous emission–detection operation of vertical-structure LED

“…Both the buffer layer and undoped GaN are etched away and a n-GaN layer is partially thinned. The number of optically-confined modes is thus reduced and the bottom Ag electrode also reflects the downward propagating light back into upward direction, [24][25][26] leading to an improvement in the light extraction efficiency. A Cr/Pt/Au n-electrode is then evaporated to generate a vertical-structure LED.…”