HexaTech demonstrated optically pumped, AlGaN-based lasers grown on single crystalline AlN substrates , to develop its UV-C LEDs.

Hexatech AlN wafer production process

Laser structures fabricated at HexaTech and tested in collaboration with North Carolina State University (NCSU) featured lasing thresholds as low as 85 kW/cm2 at wavelengths of 264 and 280 nm.

HexaTech says this AlN substrate platform is suited for UV-C opto-electronic applications.

“Our recent results show convincing evidence of the feasibility of a solid-state UV-C laser,” comments Andy Xie. "The tests not only demonstrate lasing at low pump intensities, but we also observed emission peak line widths as narrow as 0.02 nm, and further telltale signs of a properly operating laser, including spectrally resolved cavity modes, TE-mode polarisation, and elliptically-shaped far-field patterns."

The observed lasing at low pump intensities is an important milestone toward the development of semiconductor lasers operating at short wavelengths in the UV-C range. Enabled by HexaTech’s low dislocation density bulk AlN substrates, these results add to the UV-C LED and laser performance.