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Journal of Applied Mathematics and Statistical Applications | Volume: 1

August 23-24, 2018 | London, UK

Applied Physics

International Conference on

Growth technology of InGaN/GaN nanocolumn-array LED crystals on 2-inch AlN/Si substrates useful for

integrated micro-LED fabrication

Katsumi Kishino

Sophia University, Japan

sing uniform arrays of GaN nanocolumns, monolithic

integration of four-color InGaN-based nanocolumn LEDs

has been demonstrated. Two-dimensional arrangement of

such RGB micro-LEDs will, in principle, enable the fabrication

of a semiconductor video panel, which function as a micro-

LED display. The extended projection of the video image on a

screen is expected to form a widescreen LED display. One of

the basic technologies for achieving such micro-LED displays

is the fabricationof InGaN-basednanocolumn LEDs onawide-

area, for example 2-inch size or more, Si substrates. Si is easily

removed from InGaN/GaN heterojunction crystals grown

on them, enabling the flip-chip process of nanocolumn LED

crystals. The wiring on top and bottom of the LED is suitable

for a high-density integration of micro-LED pixcels, and cost-

effective fabrication of LED panels. In this study, triangular-

lattice nanopillar-array templates with a lattice constant

of 280 nm and with AlN disks on top of the underlying Si

pillars were prepared on 2-in. AlN/Si substrates through

nanoimprint lithography and dry etching. Regularly arranged

GaN nanocolumn arrays with a 220-nm diameter were grown

on the templates to fabricate wide-area emission InGaN/GaN

nanocolumn LEDs. An LED chip with an ITO electrode with an

area of 3 × 4 mm2 operated at a current of 100 mA emitted

blue-green light (504 nm in wavelength) from the entire

surface of the large emission area. The growth technology

developed here will contribute to the fabrication of two-

dimensionally arranged integrated nanocolumn micro-LEDs.