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Strongly photonic macroporous gallium phosphide networks
Schuurmans1, Vanmaekelbergh, van de Lagemaat J
1Van der Waals-Zeeman Instituut, Universiteit van Amsterdam, Valckenierstraat 65, 1018 XE Amsterdam, The Netherlands. Debye Instituut, Universiteit Utrecht, Post Office Box 80000, 3508 TA Utrecht, The Netherlands.
Science (New York, N.Y.)
|April 2, 1999
Summary
Researchers developed a new method to create porous gallium phosphide (GaP) with controllable light-scattering properties. This macroporous GaP material shows strong light scattering, especially when filled with air.
Area of Science:
- Materials Science
- Nanotechnology
- Optics
Background:
- Gallium phosphide (GaP) is a semiconductor with potential applications in optoelectronics.
- Controlling the nanostructure of GaP can tune its optical properties.
- Fabricating macropores in GaP presents challenges for material design.
Purpose of the Study:
- To develop a photo-assisted electrochemical etching technique for creating macroporous gallium phosphide (GaP).
- To investigate the structural and optical properties of the fabricated macroporous GaP.
- To demonstrate control over light scattering by tuning pore characteristics and filling media.
Main Methods:
- Photo-assisted electrochemical etching of single-crystalline GaP.
- Scanning electron microscopy (SEM) for structural analysis.
- X-ray diffraction (XRD) for crystallographic information.
- Optical transmission measurements to assess light scattering.
Main Results:
- Successfully fabricated 3D interconnected macroporous GaP networks with ~150 nm pores.
- Confirmed the disordered, nonabsorbing nature of the macroporous structures.
- Demonstrated strong light scattering, with efficiency tunable by pore filling.
- Identified air-filled macroporous GaP as having the highest scattering for visible light.
Conclusions:
- The developed photo-assisted electrochemical etching is an effective method for creating tunable macroporous GaP.
- The resulting macroporous GaP exhibits significant light scattering, useful for photonic applications.
- Controlling the refractive index of the pore-filling medium allows for photonic strength modulation.
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