Growth of 3D photonic crystals by photolysis of CrO 2 Cl 2

• Published in: Journal of crystal growth Vol. 311; no. 8; pp. 2590 - 2596
• Main Authors: Salaün, M., Audier, M., Delyon, F., Duneau, M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 2009
• Subjects: A1. Chemical vapor deposition; A2. Photolysis; A3. Holographic interferometry; B1. Photonic crystals; A2. Photolysis; B1. Photonic crystals; 42.55.Tv; 82.50.−m; A3. Holographic interferometry; 42.40.Kw; 81.15.Gh; A1. Chemical vapor deposition
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/j.jcrysgro.2009.02.008

A method of three-dimensional (3D) holography is used for the growth of photonic crystals of sub-micron cell parameters by gas decomposition in a 3D interference field of UV laser light. Either amorphous or crystalline chromium oxides are obtained by photolysis of chromyl chloride CrO 2 Cl 2 for different experimental conditions. The most interesting product is obtained for a photolysis of CrO 2 Cl 2 at low pressure, on a cooled TiO 2 single-crystal substrate and for a higher beam energy. The growth begins with the formation of epitaxial CrO 2 metastable phase which is partly transformed into Cr 2 O 3 under UV irradiation. Due to crystallographic orientational relationships between CrO 2 and Cr 2 O 3 , the growth of a well organized 3D photonic crystal of Cr 2 O 3 phase goes on according to the 3D periodic modulations of electromagnetic energy of the interference field. In the present case, the Cr 2 O 3 phase exhibits four sets of equivalent crystallographic orientations with respect to the single-crystal substrate. From such a result, one can expect to produce in a further work photonic crystals constituted of single-crystalline Cr 2 O 3 phase in epitaxy onto a Cr 2 O 3 or sapphire Al 2 O 3 substrate.