AlGaN Light‐Emitting Diodes on AlN Substrates Emitting at 230 nm. Issue 10 (20th December 2017)

• Record Type: Journal Article
• Authors: Moe, Craig G.; Sugiyama, Sho; Kasai, Jumpei; Grandusky, James R.; Schowalter, Leo J.
• Other Names: Scholz Ferdinand guestEditor.; Schwarz Ulrich guestEditor.; Vescan Andrei guestEditor.; Wernicke Tim guestEditor.
• Is Part Of: Physica status solidi. Volume 215:Issue 10(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-12-20
• Subjects: AlGaN -- ultraviolet light‐emitting diodes; Solid state physics -- Periodicals; Solids -- Industrial applications -- Periodicals; 530.41
• DOI: 10.1002/pssa.201700660
• Languages: English
• ISSNs: 1862-6300

Abstract

Abstract : Light‐emitting diodes with emission wavelengths between 230 and 240 nm are grown on AlN substrates and characterized optically and electrically. Optimized doping of the n ‐AlGaN with Si has resulted in a mean forward voltage at 200 mA of 9 V. The electroluminescence spectra is demonstrated to be free of long wavelength parasitic emission. An envelope function in the output power versus peak wavelength is shown, demonstrating the increasing dominance of i n ‐plane emission at shorter wavelengths as light extraction becomes more difficult. However, variations in device structure show that further optimization of the structure for carrier confinement and injection efficiency are also able to push performance beyond the current state of the art. Abstract : In this work UVC LEDs with emitting wavelengths as low as 230 nm and packaged powers averaging 0.1 mW are demonstrated. The shift in emission polarization across the wavelength region is displayed as a continuous function via photoluminescence. The lowest forward voltages to date at these wavelengths are achieved, and power output over time is investigated to demonstrate commercial feasibility.