Single Wall Carbon Nanotubes for p-Type Ohmic Contacts to GaN Light-Emitting Diodes

Abstract

Homogeneous films of pure single wall carbon nanotubes (SWNTs) sufficiently thin to be optically transparent in the visible range of the spectrum were employed as p-Ohmic contacts on GaN−InGaN quantum-well light-emitting diodes. The specific contact resistance of the SWNT films on the p-GaN was 1.1 × 10-2 Ω cm2 after annealing at 700 °C for 60 s under N2, which was a factor of 3 lower than standard Ni/Au contacts on the same p-GaN. The SWNT-contacted LEDs showed bright blue emission centered at 434 nm and demonstrate that the SWNT films provide a new class of electrically conducting, p-type, transparent electrode for use with photonic devices.

Highly conductive and transparent carbon nanotube composite thin films deposited on polyethylene terephthalate solution dipping

“…In addition to its flexibility, CNT films also show high transparency in a large range of solar spectrum as compared to ITO which has excellent transparency in the visible range. In recent years, transparent CNT thin films have been studied and tested in a variety of optoelectronic devices [6][7][8][9][10].…”

Improving the Ohmic Properties of Au/Ni–Mg/P–GaN Contacts by Adding Swcnt Metallization Interlayer Between Metal and P–GaN Layers

“…75 nm. This thickness guarantees a sufficient (more than 60%) optical transmittance of the SWCNT layer [12].…”

“…In [12], low-resistance ohmic contacts to p-GaN were presented based on a layer of single-walled carbon nanotubes. Thanks to its specific properties, this material is highly promising for creating ohmic contacts to p-GaN.…”

Identification and separation of metallic and semiconducting carbon nanotubes

“…The possibilities of carbon nanotube film applications have been reviewed by Gruner (Gruner 2006). The development of manufacturing reliable and uniform thin films has accelerated the activity in this area (Lee et al 2004;Saran et al 2004;Barnes et al 2007;Hu et al 2004;Zhang et al 2006a;Hu et al 2007;Li et al 2007;Ma et al 2007;Parekh et al 2007). …”