Macaluso, R. and Robert, F. and Bryce, A.C. and Calvez, S. and Dawson, M.D. (2003) Microreflectivity studies of wavelength control in oxidised AlGaAs microcavities. Materials Science and Engineering B, 102 (1). pp. 317-322. ISSN 0921-5107Full text not available in this repository. (Request a copy from the Strathclyde author)
Wet oxidation of GaAs/AlGaAs structures is an important technique in the processing of advanced devices such as vertical cavity surface emitting lasers (VCSELs). In one VCSEL application, the low-index and electrically-insulating AlxOy layers have been used to obtain high-reflectivity and broad bandwidth distributed Bragg reflector mirrors (DBRs). A further recent development has shown that combined lateral-vertical oxidation of intracavity AlGaAs layers can be used to tune the resonant wavelength of a semiconductor microcavity. The slow oxidation rate limits the lateral scale of practical wet oxidation to mesas structures of 50-100 m in width. Therefore post-processing assessment of spectral changes requires microreflectivity measurement capability with high spatial resolution. In the following, we describe the fabrication and assessment of microcavity structures in the 1.3 m range. The micro-reflectivity set-up consists of microscope-objective focussing of broadband light, combined with optics to relay the data to a spectrograph, and a CCD camera for alignment. This simple set-up allows the measurement of calibrated reflectivity for features down to a few 10's of m in size over a large spectral range (600-1800 nm). We present microreflectivity measurements of wide-bandwidth oxidised DBRs, and most significantly, for the first time to our knowledge, of oxidation control of the resonant wavelength of a microcavity in the 1.3 m range.
|Keywords:||microreflectivity, optical cavity, wavelength-control, wet oxidation, Optics. Light, Mechanics of Materials, Materials Science(all), Mechanical Engineering, Condensed Matter Physics|
|Subjects:||Science > Physics > Optics. Light|
|Department:||Faculty of Science > Physics > Institute of Photonics|
|Depositing user:||Strathprints Administrator|
|Date Deposited:||25 Jan 2008|
|Last modified:||06 Jan 2017 05:21|