Optical characterisation of 2D macroporous silicon photonic crystals with bandgaps around 3.5 and 1.3 mu m

Transmission measurements were performed on thin 2D silicon photonic crysta ls (PCs) with 1-4 crystal rows in order to investigate the effect of a fini te structure and to obtain an estimate of the crystal thickness necessary t o minimize crosstalk between adjacent waveguides, For wavelengths deep with in the H-bandgap a strong exponential decay revealing an attenuation consta nt of 10 dB per crystal row was measured. For opto-electronic applications, the lattice constant of macroporous Si was successfully downscaled from a pitch of 1.5 to 0.5 mum. Reflection measurements performed at these structu res show good agreement with corresponding bandstructure calculations exhib iting a complete bandgap around lambda = 1.3 mum. (C) 2001 Elsevier Science B.V. All rights reserved.