A continuously tunable organic DFB laser

• Published in: Microelectronic engineering Vol. 78; pp. 364 - 368
• Main Authors: Wang, J., Weimann, Th, Hinze, P., Ade, G., Schneider, D., Rabe, T., Riedl, T., Kowalsky, W.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01-03-2005; Elsevier Science
• Subjects: Applied sciences; DFB; Electronics; Exact sciences and technology; Microelectronic fabrication (materials and surfaces technology); Organic laser; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Wavelength tunable; DFB; Organic laser; Wavelength tunable; Second order; Dry etching; Electron beam lithography; Distributed feedback laser; Active layer; Doped materials; Bragg grating; Addressing; Dye laser; Microelectronic fabrication; Tunable laser; Gain; Wafer
• ISSN: 0167-9317; 1873-5568
• DOI: 10.1016/j.mee.2005.01.008

In this work, a Bragg grating with continuously tuned period
Λ, from 380 to 420
nm, was fabricated. The exposure was done by electron-beam lithography and the pattern of the gratings was transferred by a dry etching technique into the SiO
x
layer of a thermal oxidised silicon wafer. Tris (8-hydroxy quinoline) aluminum (Alq
3) doped with the laser dye 4-(dicyanomethylene)-2-methyl-6(julolidin-4-
yl-vinyl)-4
H-pyran (DCM2) was used as the organic active layer. Continuous wavelength selection was simply realized by addressing the different grating-period areas. A second-order DFB laser with varying wavelength (608.9–646.5
nm) was achieved with the radiation direction perpendicular to the sample surface. The laser threshold and output characteristics were investigated for different laser wavelengths. The FWHM of the laser was between 0.19 and 0.48
nm. A minimum threshold for laser activity occurred for the lasing wavelength between 628 and 633
nm, giving the spectral position of the gain maximum.