Deterministic Placement of Quantum-Size Controlled Quantum Dots for Seamless Top-Down Integration

• Published in: ACS photonics Vol. 4; no. 9; pp. 2165 - 2170
• Main Authors: Fischer, Arthur J, Anderson, P. Duke, Koleske, Daniel D, Subramania, Ganapathi
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 20.09.2017; American Chemical Society (ACS)
• Subjects: antibunched; InGaN; MATERIALS SCIENCE; nanophotonics; photoelectrochemical etching; photoluminescence; quantum dots; nanophotonics; InGaN; photoelectrochemical etching; quantum dots; photoluminescence; antibunched
• ISSN: 2330-4022; 2330-4022
• DOI: 10.1021/acsphotonics.7b00774

We demonstrate a new route toward the integration and deterministic placement of quantum dots (QDs) within prepatterned nanostructures. Using standard electron-beam lithography (EBL) and inductively coupled plasma reactive-ion etching (ICP-RIE), we fabricate arrays of nanowires on a III-nitride platform. Next, we integrate QDs of controlled size within the prepatterned nanowires using a bandgap-selective, wet-etching technique: quantum-size-controlled photoelectrochemical (QSC-PEC) etching. Low-temperature microphotoluminescence (μ-PL) measurements of individual nanowires reveal sharp spectral signatures, indicative of QD formation. Further, internal quantum efficiency (IQE) measurements reveal a near order of magnitude improvement in emitter efficiency following QSC-PEC etching. Finally, second-order cross-correlation (g(2)­(0)) measurements of individual QDs directly confirm nonclassical, antibunching behavior. Our results illustrate an exciting approach toward the top-down integration of nonclassical light sources within nanophotonic platforms.