Browsing by Author "Shojiki, Kanako"

Now showing 1 - 2 of 2

Fabrication of InGaN/GaN Nanodisk Structure by using Bio-template and Neutral Beam Etching Process
(2015)
Lai, Yi-Chun
;
Higo, Akio
;
Lee, Chang Yong
;
Thomas, Cedric
;
Tanikawa, Tomoyuki
Quantum dot optoelectronic devices are very attractive for their low power consumption, temperature stability, and high-speed modulation. We developed a defect-less, top-down fabrication process for sub-12-nm diameter InGaN quantum nanodisks (NDs) embedded in GaN barrier by using a combination of a bio-template and neutral beam etching. We have achieved high density of 2.6 x 10(11) cm(-2) with 6-nm in diameter and 15-nm-high nanopillars.
Nanometer scale fabrication and optical response of InGaN/GaN quantum disks
(2016-10-21)
Lai, Yi-Chun
;
Higo, Akio
;
Kiba, Takayuki
;
Thomas, Cedric
;
Chen, Shula
In this work, we demonstrate homogeneously distributed In0.3Ga0.7N/GaN quantum disks (QDs), with an average diameter below 10 nm and a high density of 2.1 x 10(11) cm(-2), embedded in 20 nm tall nanopillars. The scalable top-down fabrication process involves the use of self-assembled ferritin bio-templates as the etch mask, spin coated on top of a strained In0.3Ga0.7N/GaN single quantum well (SQW) structure, followed by a neutral beam etch (NBE) method. The small dimensions of the iron cores inside ferritin and nearly damage-free process enabled by the NBE jointly contribute to the observation of photoluminescence (PL) from strain-relaxed In0.3Ga0.7N/GaN QDs at 6 K. The large blueshift of the peak wavelength by over 70 nm manifests a strong reduction of the quantum-confined Stark effect (QCSE) within the QD structure, which also agrees well with the theoretical prediction using a 3D Schrodinger equation solver. The current results hence pave the way towards the realization of large-scale III-N quantum structures using the combination of bio-templates and NBE, which is vital for the development of next-generation lighting and communication devices.