Accession Number : ADP008139

Title :   Ge-Diffused Passive Optical Waveguide Structures in Silicon,

Corporate Author : TECHNISCHE UNIV BERLIN (GERMANY F R)

Personal Author(s) : Schmidtchen, J. ; Schuppert, B ; Splett, A. ; Petermann, K.

Report Date : APR 1992

Pagination or Media Count : 2

Abstract : For the fabrication of complex integrated optical devices such as a coherent optical receiver the separate investigation of its components like directional couplers, S-bends and Y-branches is a necessity. A promising material for its realization is silicon since it exhibits an optical absorption of below O.lcm-1 in the infrared regime (A > 1.2/micrometer) provided that waveguides with equally low losses can be produced. The goal is achieved by indiffusing Ge from a stripe containing an alloy of germanium and silicon as proposed in /1,2/ thus minimizing losses due to free carriers. Silicon also offers the potential of being the most developed material for electronic applications making it suitable for an opto-electronic integration. To characterize the waveguides the number of propagating modes and the waveguide losses were determined. Applying a Cut-Back technique the loss was evaluated by measuring the insertion losses of the system polarization maintaining fibre/chip/detector for three different sample lengths. Waveguides with a Ge-indiffusion depth of 1.54 micrometer and a maximum Ge concentration at the surface of 4.5% at 1.3 micrometer have been made.

Descriptors :   *COUPLERS, *GERMANIUM, *SILICON, *INFRARED EQUIPMENT, *OPTICAL WAVEGUIDES, ABSORPTION, ALLOYS, DEPTH, DETECTORS, DIRECTIONAL, ELECTRONICS, FABRICATION, INTEGRATION, LOSSES, MATERIALS, NUMBERS, POLARIZATION, RECEIVERS, STRIPES, SURFACES, WAVEGUIDES, DIFFUSION, GERMANY, PASSIVE SYSTEMS.

Subject Categories : Optics
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE