A cost-effective method for mass production of quantum dot lasers has been discovered

Scientists at the Electronics and Telecommunications Research Institute (ETRI) in South Korea have found a way to mass produce quantum dot lasers.

Quantum dot lasers are precision laser devices that produce light using semiconductor particles only a few nanometers in size.

These particles are called quantum dots and allow for a great deal of control over the properties of the laser, making them extremely useful in applications that require precise tuning of light on a very small scale.

For example, quantum dot lasers could lead to high-quality optical communication devices that transmit information over long distances using light. These devices are critical to the rapid transfer of data across the Internet, the smooth operation of servers within and between data centers, and accurate medical imaging.

In their new research, ETRI scientists have successfully produced and tested laser diodes using quantum dots, components used in optical communications devices.

Overcoming the challenges of quantum dot laser fabrication

Scientists wanted to produce large quantities of high-quality quantum dot laser diodes, but found that conventional methods used to do so were slow, inefficient, required an expensive indium phosphide (InP) substrate, and therefore were not scalable.

This forced them to look for alternatives, and they soon came across a technique called metal-organic chemical vapor deposition (MOCVD), which can create very thin (nanoscale) layers of material on a surface.

MOVCD is widely used for research purposes. But for the first time, the ETRI team decided to use it to produce quantum dot laser diodes, and it worked.

“We have successfully developed indium arsenide/gallium arsenide (InAs/GaAs) quantum dot laser diodes on gallium arsenic (GaAs) substrates that are suitable for the 1.3 µm wavelength band used in optical communications,” the authors note. tests.

MOCVD as a quantum dot fabrication process provided higher production efficiency and good uniformity compared to conventional methods. Moreover, a substrate (GaAs) was used that is available for less than one third of the price of InP substrates.

When they tested mass-produced quantum dot laser diodes, “the semiconductor lasers demonstrated continuous operation at temperatures up to 75 degrees Celsius, representing a world-leading achievement in MOCVD results.”

Mass-produced quantum dot lasers have many advantages

MOCVD allowed researchers to produce dot lasers quickly, efficiently, scalably and cost-effectively. They claim that their approach can reduce the cost of producing semiconductor lasers by more than 80 percent.

This would further reduce the costs of the technologies that use these lasers. For example, the reduced cost of quantum dot lasers will significantly reduce the price of advanced optical communication devices.

“In modern society, optical communication is the backbone of our industry. The achievements of this study are expected to revolutionize the development of optical sources, connecting residential complexes with large cities and submarine optical cables,” the authors of the study note.

However, current research work is only a stepping stone. Scientists need to conduct more research to further optimize and confirm the feasibility of their approach before they begin using MOCVD to produce quantum dot lasers on a commercial scale.

The study was published in Journal of Alloys and Compounds.