9 August 2021
BluGlass demos first RPCVD tunnel-junction laser diodes
BluGlass Ltd of Silverwater, Australia – which develops low-temperature, low-hydrogen remote-plasma chemical vapor deposition (RPCVD) technology for manufacturing devices such as laser diodes, next-generation LEDs and micro-LEDs – says it has demonstrated working tunnel-junction laser diodes in a first proof-of-concept using its proprietary RPCVD technology.
The novel laser diode prototypes leverage BluGlass’ unique RPCVD tunnel-junction technology, developed over many years for use in high-power products including laser diodes and high-brightness LEDs.
Designed to enable higher power and more efficient lasers for use in commercial applications such as 3D printing and industrial welding, the RPCVD tunnel-junction laser diode prototypes have demonstrated good lasing behaviour, says BluGlass, helping to confirm the potential of the RPCVD laser diode designs to address the critical performance requirements for high-value gallium nitride (GaN) laser diode applications.
GaN laser diode applications are currently limited by optical and resistive loss in the magnesium-containing p-type layers, which leads to low conversion efficiencies (typically 40-45%, compared with nearly 90% in GaN-based LEDs). Almost 50% of the power consumed when operating GaN laser diodes is lost in the form of heat due to the highly resistive p-type layers, traditionally needed to create the electrical circuit in a laser diode.
BluGlass says that its novel approach, enabled by the benefits of low-temperature, low-hydrogen RPCVD growth, can eliminate the need for these highly resistive and performance-losing p-type layers. RPCVD-enabled novel designs replace the p-type cladding layer with an RPCVD tunnel junction and second n-type cladding layer – a dual n-wave laser diode – paving the way to significantly improve laser diode performance in the future.
BluGlass says that it will continue to optimize its RPCVD tunnel-junction laser diode design, epitaxy and fabrication to maximize laser performance.
“This is an important validation of the potential of our unique RPCVD and tunnel-junction technologies,” believes executive chair James Walker. “This achievement is a testament to the efforts of our leading-edge team in developing a range of innovative laser diode products, including this world-first demonstration of dual-n-wave lasers,” he adds.
“While these novel lasers have significant development required before the launch of future RPCVD-enhanced products, our significantly further advanced standard (MOCVD) laser diode product development continues to focus on solving reliability and improving our downstream production ahead of launching commercial products to waiting customers.”