Taiwanese Researchers Improve InGaN VCSELs
Composition-graded electron blocking layer boosts output power
Researchers from the National Chiao Tung University, the National Changhua University of Education, Advanced Optoelectronic Technology Inc, and the Research center for Applied Science in Taiwan have designed and made an InGaN VCSEL with a composition-graded electron blocking layer (GEBL).
In their study, published in Laser Physics Letters, they been demonstrated that laser output performance is improved by using a GEBL when compared to the typical VCSEL structure of a rectangular electron blocking layer.
The output power obtained at 20kAcm-2 is enhanced by a factor of 3.8 by the successful reduction of threshold current density from 12.6 to 9.2kA cm-2 and the enlarged slope efficiency.
Numerical simulation results also suggest that the improved laser output performances are due mainly to the reduction of electron leakage current and the enhanced hole injection efficiency in the multiple-quantum-well (MQW) active region.
'Design and fabrication of a InGaN vertical-cavity surface-emitting laser with a composition-graded electron-blocking layer' by BC Lin et al, appeared in Laser Phys. Lett. 11 085002 doi:10.1088/1612-2011/11/8/085002
AngelTech Live III: Join us on 12 April 2021!
AngelTech Live III will be broadcast on 12 April 2021, 10am BST, rebroadcast on 14 April (10am CTT) and 16 April (10am PST)
and will feature online
versions of the market-leading physical events: CS International
and PIC International
PLUS a brand new Silicon Semiconductor International
Thanks to the great diversity of the semiconductor industry, we are always chasing new markets and developing a range of exciting technologies.
2021 is no different. Over the last few months interest in deep-UV LEDs has rocketed, due to its capability to disinfect and sanitise areas and combat Covid-19. We shall consider a roadmap for this device, along with technologies for boosting its output.
We shall also look at microLEDs, a display with many wonderful attributes, identifying processes for handling the mass transfer of tiny emitters that hold the key to commercialisation of this technology.
We shall also discuss electrification of transportation, underpinned by wide bandgap power electronics and supported by blue lasers that are ideal for processing copper.
Additional areas we will cover include the development of GaN ICs, to improve the reach of power electronics; the great strides that have been made with gallium oxide; and a look at new materials, such as cubic GaN and AlScN.
Having attracted 1500 delegates over the last 2 online summits, the 3rd event promises to be even bigger and better – with 3 interactive sessions over 1 day and will once again prove to be a key event across the semiconductor and photonic integrated circuits calendar.
So make sure you sign up today and discover the latest cutting edge developments across the compound semiconductor and integrated photonics value chain.
REGISTER FOR FREE