Sogang University-Sungkyunkwan University Joint Research Team Develops a Novel Doping Technology for Quantum Dot Semiconductors


The 2023 Nobel Prize in Chemistry was awarded to three scholars, Munji Bowendy, Luis Bruce, and Alexey Ekimov for their contributions to the discovery and synthesis of quantum dots. Quantum dots are extremely small semiconductor crystals, typically just a few nanometers (one billionth of a meter) in size, which can emit light of various colors depending on their precise size. These quantum dots represent next-generation semiconductor materials that can freely control the color of light emitted from materials with fine size control. Leveraging these properties, quantum dots have been industrialized as display devices that offer bright and vibrant images. Furthermore, the application is expanding to include virtual reality/augmented reality display devices and quantum sensing technologies.

However, despite being semiconductors, quantum dots currently lack the technology to control their electrical polarity (the polarity based on electron movement for n-type semiconductors and hole movement for p-type semiconductors). Given that various semiconductor devices are fundamentally composed of a combination of p-type and n-type semiconductors, controlling the electrical polarity of quantum dot semiconductors is a crucial challenge.

On the 11th, a joint research team led by Professor Moon Sung Kang from the Department of Chemical and Biomolecular Engineering at Sogang University, Professor Sohee Jung from the Department of Energy Science at Sungkyunkwan University, and Professor Ji-sang Park from the Sungkyun Institute of Nanoscience and Technology announced that they have developed a technology to control the polarity of quantum dot semiconductors through doping (introducing heterogeneous elements into semiconductors). Unlike conventional technologies that involve complex post-processing to dope heterogeneous elements (zinc) into already manufactured quantum dot semiconductors, this research is significant in that it developed the first simplified doping technology that introduces heterogeneous elements (zinc) from the synthesis process of growing quantum dot crystals.

The p-type material synthesized through this doping technology shows the best electrical properties among the reported p-type InAs quantum dot semiconductors to date. The researchers have succeeded in fabricating a logic device using quantum dot semiconductors with both p-type and n-type electrical characteristics.
The joint researchers said, “We believe that the academic significance has been recognized in that we have succeeded in a very difficult technology to precisely introduce heterogeneous elements into fine semiconductor crystals that are only a few nanometers in size. In particular, the developed InAs quantum dot semiconductor, which has attracted significant attention from the industry, will be able to contribute to the development of next-generation high-performance infrared devices.”
This research was conducted with the support of the Future Materials Discovery Program and the Mid-Career Researcher Program of the National Research Foundation of Korea, both supported by the Ministry of Science and ICT and with the support of Samsung Future Technology Cultivation Project. It was published in the international academic journal “Science Advances (Impact Factor 13.6 in 2022)” on November 10, 2023.

-Paper link:

-Paper title: P- and N-type InAs nanocrystals with innately controlled semiconductor polarity