Characterization of the InGaN/GaN-based multi-quantum well distributed feedback lasers.
We present a device fabrication technology and measurement results of both optically pumped and electrically injected InGaN/GaN-based distributed feedback (DFB) lasers operated at room temperature. For the optically pumped DFB laser, we demonstrate a complex coupling scheme for the first time, whereas the electrically injected device is based on normal index coupling. Threshold currents as low as 1.1 A were observed in 500 µm long and 10 µm wide devices. The 3rd order grating providing feedback was defined holographically and dry-etched into the upper waveguiding layer by chemically-assisted ion beam etching. Even when operating these lasers considerably above threshold, a spectrally narrow emission (3.5 Å) at wavelengths around 400 nm was seen.
Hofstetter, D. ; Thornton, R. L. ; Romano, L. T. ; Bour, D. P. ; Kneissl, M .; Donaldson, R. M. ; Dunrowicz, C Characterization of the InGaN/GaN-based multiquantum well distributed feedback lasers. MRS Fall Meeting. Symposium G: GaN and related alloys; 1998 November 30- December 4; Boston, MA. In MRS Internet Journal of Nitride Semiconductor Research. 1999; 4: U74-U79.