GaN LEDs fabricated using SF ₆ plasma RIE

Abstract

In this work, the authors report a cost-effective fabrication method for making gallium nitride (GaN) light emitting diode (LED) arrays using SF 6 plasma in a conventional reactive-ion etching (RIE) system. The etch rates for GaN were investigated with different radio-frequency power and carrier substrates. The surface roughness due to the etching was also determined for the various recipes used. The optical intensity and the temperature change during operation of the fabricated LED's were investigated. The effect of post-fabrication annealing on enhancement in the electrical and optical properties of the LED's was investigated.

Vertical GaN Nanowires and Nanoscale Light-Emitting-Diode Arrays for Lighting and Sensing Applications

“…This was done to avoid the usage of more commonly used, but corrosive, chloride- and bromide-based gases in the fabrication process, which may damage the established Cr masks. Moreover, to employ such highly toxic gases, a costly reactive chamber with specific filtration system is required, not to mention a high risk of continuously damaging the vacuum systems …”

“…Moreover, to employ such highly toxic gases, a costly reactive chamber with specific filtration system is required, not to mention a high risk of continuously damaging the vacuum systems. 36 The detailed mechanism of the SF 6 /H 2 dry etching has not been to date fully understood. However, some previous studies 29,37−40 showed that GaN reacts with SF 6 /H 2 and produces volatile compounds of NF 3 (boiling point T B = −129 °C) and NH 3 (T B = −33 °C), as well as nonvolatile GaF 3 (T B ≈ 1000 °C) , which would be removed by physical ion bombardment of hydrogen and SF x .…”