Our work provides these experimental data. The correlation of these results with the growth design and with the functional properties of these structures will allow closing the loop to optimize the performance of devices based
in stacking of QDs. Conclusions In summary, we have analyzed the 3D distribution of InAs/GaP/GaAs stacked QDs by electron tomography using HAADF images. For this, we have VS-4718 order optimized the needle-shaped specimen fabrication procedure by FIB for samples with multiple layers of QDs. We have found that contrary to what could be derived from a 2D conventional TEM analysis, the QDs do not follow a vertical alignment, but there is a deviation angle of 10° ± 1°. The unambiguous determination of the 3D distribution of QDs is a key for the interpretation of the optoelectronic properties of devices based in stacking of QDs. Authors’ information JHS is a PhD student at the Universidad de Cádiz. MH
is an associate professor at the Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica, Universidad de Cádiz. DAA holds a postdoctoral position as Research Associate in the School of Engineering and Physical Sciences at Heriot-Watt University CP673451 order and the Scottish Institute for Solar Energy Research (SISER). SIM is a full professor at the Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica, Universidad de Cádiz. Acknowledgments This work was supported by the Spanish MINECO (projects Epigenetics inhibitor TEC2011-29120-C05-03 and Consolider Ingenio 2010 CSD2009-00013) and the Junta de Andalucía (PAI research group TEP-946 INNANOMAT).
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