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arXiv · 1812.07708

Blue (In,Ga)N Light-Emitting Diodes with Buried n+-p+ Tunnel Junctions by Plasma-Assisted Molecular Beam Epitaxy

YongJin Cho·Shyam Bharadwaj·Zongyang Hu·Kazuki Nomoto·Uwe Jahn·Huili Grace Xing·Debdeep Jena
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Abstract

Blue light-emitting diodes (LEDs) consisting of a buried n+-p+ GaN tunnel junction, (In,Ga)N multiple quantum wells (MQWs) and a n+-GaN top layer are grown on single-crystal Ga-polar n+-GaN bulk wafers by plasma-assisted molecular beam epitaxy. The (In,Ga)N MQW active regions overgrown on the p+-GaN show chemically abrupt and sharp interfaces in a wide range of compositions and are seen to have high structural and optical properties as verified by X-ray diffraction and spatially resolved cathodoluminescence measurements. The processed LEDs reveal clear rectifying behavior with a low contact and buried tunnel junction resistivity. By virtue of the top n+-GaN layer with a low resistance, excellent current spreading in the LEDs is observed at low currents in this device structure. A few of new device possibilities based on this unique design are discussed.

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YongJin Cho, Shyam Bharadwaj, Zongyang Hu, Kazuki Nomoto, Uwe Jahn, Huili Grace Xing, Debdeep Jena. 2018-12-19. Blue (In,Ga)N Light-Emitting Diodes with Buried n+-p+ Tunnel Junctions by Plasma-Assisted Molecular Beam Epitaxy. https://doi.org/10.7567/1347-4065%2Fab1e78

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